Main Topic 1 intro etiology pathophysiology clinical Manifestations diagnosis complications treatment
Prevention (National Malaria Control Programme)
Yemen is classified as high risk area for malaria. Non immune individuals, whether visitors from non-malarious
countries intending to visit Yemen or Yemeni nationals from non malarious areas in Yemen intending to visit
malaria-endemic areas in their country, should take the necessary measures to protect themselves from malaria.
These measures include:
1) Mosquito bite prevention by sleeping under bednet, if possible treated with insectide, and using a mosquito
repellant after sunset.
2) Chemoprophylaxis.
Treatment If possible, travelers should seek medical advice on chemoprophylaxis of malaria. The recommended
Physicians caring for patients with malaria need to be aware of current information regarding malaria because resistance to antimalarial drugs has complicated therapy and drug to be used as chemoprophylaxis for malaria is mefloquine in Yemen; Doxycycline can be used if
prophylaxis. mefloquine is contraindicated. None of the medicine used for chemoprophylaxis provides a 100% protection
Fever without an obvious cause in any patient who has left a P. falciparum– endemic area within 30 days and is nonimmune should be considered a medical emergency. from malaria infection: all fever in travelers to malarious areas should be considered malaria until proven
Thick and thin blood smears should be obtained immediately, and all children with symptoms of severe disease should be hospitalized. If negative, blood films should be repeated otherwise by laboratory examination (microscopy or RDTs).
every 12 hr until 3 smears are documented as negative.
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If the patient is severely ill, antimalarial therapy should be initiated immediately
▪️ Outpatient therapy generally is not given to nonimmune children but may be considered in immune or semi-immune children who have:
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low-level parasitemia (<1%),
no evidence of complications defined by the World Health Organization (WHO),
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no vomiting, and a lack of toxic appearance;
who are able to contact the physician or emergency department at any time;
🆘Treatment for Plasmodium Falciparum Malaria (according to national antimalarial program)
and in whom follow-up within 24 hr is ensured.
Complications of Plasmodium Falciparum MALARIA
WHO has identified 10 complications of P. falciparum malaria that define severe malaria.
Pathogenesis 🔷 Severe malarial anemia (hemoglobin level <5 g/dL) is the most common severe complication of malaria in children.
Plasmodium species exist in a variety of forms and have a complex life cycle that enables them to survives
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in different cellular environments in the human host (Asexual phase) and the mosquito (sexual phase).
Two-step process occurs in humans, with the 1st phase in hepatic cells (exoerythrocytic phase) and
Clinical Manifestations 🔹
Anemia is associated with:
🔹 hemolysis
removal of infected erythrocytes by the spleen and impairment of erythropoiesis likely play a greater role than hemolysis in the pathogenesis of severe
the 2nd phase in the RBCs (erythrocytic phase).
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The incubation periods are:
🔹 9-14 days for P. falciparum,
malarial anemia. The primary treatment for severe malarial anemia is blood transfusion.
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🔹 The exoerythrocytic phase begins with inoculation of sporozoites into the bloodstream by a female
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12-17 days for P. vivax (can be as long as 6-12 mo),
16-18 days for P. ovale, and 18-40 days for P. malariae.
Cerebral malaria is defined as the presence of coma/altered mental status in a child with P. falciparum parasitemia and an absence of other reasons for
coma. Often develops after the patient has been ill for several days but may develop precipitously. Cerebral malaria has a fatality rate of 15–40% and is
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Anopheles mosquito. Within minutes, the sporozoites enter the hepatocytes of the liver, where they associated with:
develop and multiply asexually as a schizont . After 1-2 wk, the hepatocytes rupture and release
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A prodrome lasting 2-3 days is noted in some patients before parasites are detected in the blood.
Prodromal symptoms include headache, fatigue, anorexia, myalgia, slight fever, and pain in the chest, abdomen, and joints.
🔹 long-term cognitive impairment in children.
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thousands of merozoites into the circulation.
The erythrocytic phase of Plasmodium asexual development begins when the merozoites from the
liver penetrate erythrocytes. Once inside the erythrocyte, the parasite transforms into the ring form,
Children with malaria often lack the typical paroxysms in adults (high fever, followed by shaking chills and then diaphoresis) and may have
nonspecific symptoms, including fever (may be low-grade but is often >40°C [104°F]), headache, drowsiness, anorexia, nausea, vomiting, and 🔹 repeated seizures.
hypoglycemia (children with true cerebral malaria fail to arouse from coma even after receivinga dextrose infusion that normalizes their glucose level).
Physical findings may include
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whichthen enlarges to become a trophozoite ,These latter 2 forms can be identified with Giemsa stain on
blood smear, the primary means of confirming the diagnosis of malaria. The trophozoite multiplies
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diarrhea.
While the rupture of schizonts that occurs every 48 hr with P. vivax and P. ovale and every 72 hr with P. malariae can result in a classic pattern
of fevers every other day (P. vivax and P. ovale ) or every 3rd day (P. malariae ), periodicity is less apparent with P. falciparum, and mixed infections
Diagnosis
high fever, seizures, muscular twitching, rhythmic movement of the heador extremities, contracted or unequal pupils, retinal hemorrhages, hemiplegia, absent
or exaggerated deep tendon reflexes, and a positive Babinski sign.
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asexually to produce a number of small erythrocytic merozoites that are released into the bloodstream History and Physical examination -Lumbar puncture reveals increased pressure and mildly increased cerebrospinal fluid protein, typically with no CSF pleocytosis and a normal CSF glucose
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when the erythrocyte membrane ruptures, which is associated with fever.
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and may not be apparent early on in infection, when parasite broods have not yet synchronized.
🔹 Distinctive physical signs may include; splenomegaly (common), hepatomegaly, and pallor as a consequence of anemia. 🔹
Important criteria that suggest P. falciparum malaria include: Malaria retinopathy- funduscopic findings (retinal hemorrhages, peripheral whitening, macular whitening, vessel changes) are relatively specific for cerebral
Over time, some of the merozoites develop into male and female gametocytes that complete the
Plasmodium life cycle when they are ingested during a blood meal by the female anopheline mosquito.
Typical laboratory findings include: anemia, thrombocytopenia, and a normal or low leukocyte count. The erythrocyte sedimentation rate is 🔹
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symptoms occurring <1 mo after return from an endemic area,
>2% parasitemia, 🔹
malaria.
Treatment of cerebral malaria:
Etiology
The male and female gametocytes fuse to form a zygote in the stomach cavity of the mosquito. After a
series of further transformations, sporozoites enter the salivary gland of the mosquito and are inoculated
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often elevated.
P. falciparum is the most severe form of malaria and is associated with higher density parasitemia (as high as 60%) and a number of 🔹 ring forms with double-chromatin dots,
and erythrocytes infected with>1 parasite.
•Antimalarial medications
•Supportive therapy includes: evaluation of and treatment of seizures and hypoglycemia.
Malaria is caused by intracellular Plasmodium
protozoa transmitted to humans by female 🔹
into a new host with the next blood meal
Physiology and pathogenesis in malaria differ according to species:
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complications, in contrast to malaria caused by P. ovale, P. vivax, and P. malariae, which usually result in parasitemias of <2%.
The differences in parasitemia reflect that P. falciparum infects both immature and mature erythrocytes, whereas P. ovale and P. vivax primarily
The diagnosis of malaria is established by identification of organisms on Giemsa-stained smears of
peripheral blood or by rapid immunochromatographic assay (rapid diagnostic test).
•Cerebral edema with increased intracranial pressure is the leading cause of death in children, but treatment with mannitol and corticosteroids has not
improved outcomes in these children.
Malaria is an acute illness characterized by
paroxysms of fever, chills, sweats, fatigue, anemia, 🔹
Anopheles mosquitoes.
Many species of Plasmodium were known to
Infection with all species leads to fever, caused by the host immune response when erythrocytes rupture
and release merozoites into the circulation, and anemia, caused by hemolysis and bone marrow
infect immature erythrocytes and P. malariae infects only mature erythrocytes.
Like P. falciparum, P. knowlesi has a 24 hr replication cycle and can also lead to very high-density parasitemia.
Both thick and thin blood smears should be examined. The concentration of erythrocytes on a thick
smear is 20-40 times that on a thin smear and is used to quickly scan large numbers of
🔷 Respiratory distress is a poor prognostic indicator in severe malaria and appears to be caused by metabolic acidosis rather than intrinsic pulmonary
disease. The primary therapy of malaria appears to be the most effective way to address acidosis.
and splenomegaly. Malaria remains one of the
leading causes of morbidity and mortality
cause malaria in humans:
P. falciparum, P. malariae, P. ovale, P. vivax , 🔹
suppression.
Severe malaria is more common in P. falciparum because of several process, including higher-density
World Health Organization Criteria for Severe Malaria, 2000
1. Impaired consciousness 🔸
erythrocytes.
The thin smear allows for positive identification of the malaria species and determination 🔷 Seizures are a common complication of severe malaria, particularly cerebral malaria.
Malaria (Plasmodium)
2. Prostration Benzodiazepines are first-line therapy for seizures, and intrarectal diazepam has been used successfully in children with malaria and seizures.
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worldwide.
and P. knowlesi
Malaria also can be transmitted through blood
parasitemia, which may lead to excessive production of proinflammatory cytokines; cytoad herence of P.
falciparum -infected erythrocytes to the vascular endothelium; and polyclonal activation, resulting in both 3. Respiratory distress (a result of metabolic acidosis) 🔸
of the percentage of infected erythrocytes and is useful in following the response to therapy.
Although P. falciparum is most likely to be identified from blood just after a febrile Many seizures resolve with a single dose of diazepam. For persistent seizures, phenobarbital or phenytoin are the standard medications used.
Phenytoin may be preferred for seizure treatment, particularly in hospitals or clinics where ventilatory support is not available.
Malarial deaths in areas of high malaria
transmission occur primarily in children <5 yr of age,
transfusion (whole blood, packed red blood
cells (RBCs), platelets, and leukocytes), use of
hypergammaglobulinemia and the formation of immune complexes. Cytoadherence of infected
erythrocytes to vascular endothelium can lead to obstruction of blood flow and capillary damage, with
4. Multiple seizures
5. Jaundice
6. Hemoglobinuria
paroxysm, most children with malaria will have a positive blood smear regardless of the time the
smear is obtained. 🔷 Hypoglycemia is a complication of malaria that is more common in children, pregnant women, and patients receiving quinine therapy. Patients may have
a decreased level of consciousness that can be confused with cerebral malaria.
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contaminated needles, transplacentally from a resultant vascular leakage of blood, protein, and fluid and tissue anoxia. Most guidelines recommend at least 3 -ve blood smears to rule out malaria in children in whom
but in areas of low transmission, a large percentage pregnant woman to her fetus and through Parasite anaerobic metabolism may also lead to hypoglycemia and metabolic acidosis. The 7. Abnormal bleeding malaria is strongly suspected, because low-level parasitemia could potentially go undetected early Any child with impaired consciousness and malaria should have a glucose level checked, and if glucometers are not immediately available, an empirical bolus
of deaths may occur in older children and adults. 8. Severe anemia of dextrose should be given. Hypoglycemia is associated with increased mortality and neurologic sequelae.
organ transplantation.
Epidemiology
cumulative effects of these pathologic processes may lead to cerebral, cardiac, pulmonary, renal, and
hepatic failure.Immunity after Plasmodium sp. infection is incomplete, preventing severe disease but still 9. Circulatory collapse 🔸
in the illness.
Imunochromatographic test for P. falciparum histidine-rich protein (HRP2) and aldolase is 🔷 Circulatory collapse (algid malaria) is a rare complication that manifests as hypotension, hypothermia, rapid weak pulse, shallow breathing, pallor, 🆘Management of severe (complicated) falciparum malaria cases:
Malaria is a major worldwide problem. allowing future infection.
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10. Pulmonary edema
P. vivax malaria is a frequent cause of severe disease and death (caused by severe anemia and sometimes splenic rupture) as P. falciparum in
approved for testing for P. falciparum and P. vivax. Aldolase is present in all 5 of the malaria species and vascular collapse.
🔶 First Option:
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that infect humans. PCR is more sensitive than microscopy but is technically more complex. It is most likely caused by bacterial superinfection, since up to 15% of children in endemic areas with severe malaria may have concurrent bacteremia.
Initial treatment - Artesunate
Repeated episodes of infection occur because the parasite has developed a number of immune-evasive
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some areas.
P. ovale malaria is the least common type of malaria. It is similar to P. vivax malaria and usually is found in conjunction with P. falciparum
Differential Diagnosis includes: Death may occur within hours. Any child with severe malaria and hypotension or hypoperfusion should have a blood culture obtained and should be treated
empirically for bacterial sepsis.
Follow-on treatment - ACT
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strategies, such as intracellular replication, vascular cytoadherence that prevents infected erythrocytes viral infections such as influenza and hepatitis, sepsis, pneumonia, meningitis, encephalitis, Once the patient recovers sufficiently and can tolerate oral treatment, a full ACT should be administered to complete the treatment of the patient.
from circulating through the spleen, rapid antigenic variation, and alteration of the host immune system
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malaria.
P. malariae is the mildest and most chronic of all malaria infections. Nephrotic syndrome is a rare complication of P. malariae infection which
endocarditis, gastroenteritis, pyelonephritis, brucellosis, leptospirosis, tuberculosis, relapsing fever, Long-term cognitive impairment occurs in 25% of children with cerebral malaria and also in children with repeated episodes of uncomplicated Artesunate powder for injection 60 mg:
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resulting in partial immune suppression.
🔹 Resistant malaria in:
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is poorly responsive to corticosteroids.
typhoid fever, yellow fever, viral hemorrhagic fevers, amebic liver abscess, neoplasm, and collagen
vascular disease
disease. Prevention of attacks in these children may improve educational attainment.
🔷 Hyperreactive malarial splenomegaly (HMS) is a chronic complication of P. falciparum malaria in which massive splenomegaly persists after
It should be administered in a dose of 2.4 mg/kg body weight IV or IM given on admission (time = 0), then at 12 h and 24 h, then once daily. As soon as the patient can swallow
provide a full ACT treatment course.
🔹 Erythrocytes containing hemoglobin S (sickle erythrocytes) resist malaria parasite growth.
▪️ P. knowlesi malaria is most often uncomplicated but can lead to severe malaria and death if high-density parasitemia is present.
Recrudescence after a primary attack may occur from the survival of erythrocyte forms in the blood stream. Long-term relapse is caused by
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treatment of acute infection. The vial of Artesunate powder should be mixed with 1 ml of 5% sodium bicarbonate solution (provided) and shaken 2-3 minutes for better dissolution.
🔹 Erythrocytes lacking Duffy blood group antigen are relatively resistant to P. vivax, and
Erythrocytes containing hemoglobin F (fetal hemoglobin) & ovalocytes are resistant to P. falciparum. release of merozoites from an exoerythrocytic source in the liver, which occurs with P. vivax and P. ovale, or from persistence within the
▪️ Major critria include:
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Then,
In hyperendemic areas, newborns rarely become ill with malaria, in part because of passive maternal
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erythrocyte, which occurs with P. malariae and rarely with P. falciparum.
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splenomegaly (>10 cm),
IgM > 2 SD above local mean, 🔸 1. for IV administration: add 5 ml of 5% glucose or normal saline to make the concentration of artesunate as 10 mg/ml and administer by slow infusion
2. for IM administration: add 2 ml of 5% glucose or normal saline to make the concentration of artesunate as 20 mg/ml
antibody and high levels of fetal hemoglobin.
Children 3 mo to 2-5 yr of age have little specific immunity to malaria species and therefore suffer yearly
Congenital malaria is acquired from the mother prenatally or perinatally. Usually occurs in the offspring of a nonimmune mother with P. vivax
or P. malariae infection, although it can be observed with any of the human malaria species.
▪️ high levels of antibodies to a blood-stage P. falciparum antigen, and
a clinical response to an antimalarial drug. HMS occurs exclusively in children in endemic areas with repeated exposure to malaria and is thought to be
🔶 Second Option: Artemether i.m
attacks of debilitating and potentially fatal disease.
Immunity is subsequently acquired, and severe cases of malaria become less common.
Sign or symptom typically occurs between 10 and 30 days of age (range: 14 hr to several months of age), include fever, restlessness, drowsiness,
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pallor, jaundice, poor feeding, vomiting, diarrhea, cyanosis, and hepatosplenomegaly.
Malaria in pregnancy is a major health problem in malaria endemic countries, can be severe, and is associated with adverse outcomes in the
caused by an impaired immune response to P. falciparum antigens. Prolonged antimalarial prophylaxis (for at least 1 yr, typically with chloroquine, quinine, or
mefloquine) is required to treat this syndrome if the child remains in a malaria endemic area. Spleen size gradually regresses on antimalarial prophylaxis but
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Doses of i.m. artemether and rectal artesunate:Artemether i.m. (intramuscular injection should be given to the anterior thigh):
🔸 Artemether i.m. 3.2 mg / kg divided into two doses in the first day (1.6mg/kg every 12hours in the first day), followed by 1.6 mg / kg daily for the next 6 days; or
Artemether i.m. 3.2 mg / kg divided into two doses in the first day (1.6mg/kg every 12hours in the first day), followed by 1.6 mg / kg daily for at least 3 days (to be the total 4
Both T-cell and antibody responses are important in development of biologic and clinical immunity to often increases again if prophylaxis is stopped.Other complications in children include acute kidney injury and jaundice, both of which are associated with a
fetus or neonate, including intrauterine growth restriction and low birthweight, even in the absence of transmission from mother to child. days of treatment by Artemether i.m), and provide a full treatment course of the first line oral treatment
Plasmodium spp.
Both T-cell and antibody responses are important in development of biologic and clinical
worse outcome and prostration
🔷 Prostration is defined as the inability to sit, stand, or eat without support, in the absence of impairedconsciousness. The pathophysiology of this
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🔸 Third Option: Quinine dihydrochloride injaction for the treatment of severe malaria:
immunity to Plasmodium spp.
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prostration is not well understood.
Uncommon complications include: hemoglobinuria, abnormal bleeding, and pulmonary edema. (Note:pulmonary edema is more frequent in
🔸 Intravenous quinine dihydrochloride should be given by rate-controlled infusion in saline or 5% dextrose solu tions at a rate not exceeding 5 mg salt/kg body weight per hour.
Dose of Quinine for children: 20 mg of salt/kg (loading dose) by IV infusion over 4 hours, then 12 hours after the start of the loading dose give a maintenance dose of quinine, 10
mg salt/kg over 2hours. this repeated every 12 hours, until the patient can swallow, then quinine tablets ,10 mg salt /kg ,8 hourly to complete 7- days course, or quinine IV given for at
adolescents and adults). least 3 days and then shift to the first line (AS+S/P) if the patient can swallow.
•If this is not possible to give quinine by intravenous infusion, then it should be given by intramuscular injection to the anterior thigh, not the buttock (to avoid sciatic nerve injury). The
first dose should be split, 10 mg/kg to each thigh. Undiluted quinine dihydrochloride at a concentration of 300 mg/ml is acidic (pH 2) and painful when given by intramuscular
🔸unitsRecommendations
injection, so it is best either formulated or diluted to concentrations of 60–100 mg/ml for intramuscular injection
for use of antimalarial medicines in remote public health
protozoa Rectal artesunate is the drug of choice for pre-referral treatment of severe malaria in the remote health facilities where health workers do not have access (or cannot
practice) safe intramuscular injections ofartesunate or artemether or quinine Artesunate rectal capsules / suppositories (50 or 200 mg per retocap): 10 mg / kg should be given
rectally as soon as possible, once a diagnosis of severe malaria is made.
continue If the rectal capsule is expelled within the first hour, another rectal capsule should be inserted immediately. A second dose can be repeated after 24 hours.
Supportive therapy is important and may include RBC transfusion(s) to maintain the hematocrit at >20%, supplemental oxygen and ventilatory support for pulmonary
edema or cerebral malaria, careful IV rehydration for severe malaria, IV glucose for hypoglycemia, anticonvulsants for cerebral malaria with seizures, and dialysis for
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renal failure.
Corticosteroids are not recommended for cerebral malaria because they do not improve outcomes.
🆘Treatment of non-falciparum malaria cases
🔹 Vivax and ovale malaria cases:-
-Chloroquine as a schizonticidal drug in a dose of 10mg/kg at the first and second days and then 5mg/kg at the third day.
- Primaquine as an anti-relapse measure in a dose of 0.25 mg/kg daily for 14 days or 0.75 mg/kg weekly for 8 weeks in moderate G6PD deficient patients.
The weekly dose is 3 times the amount indicated for the daily doses. (the strength recommended is 7.5 mg tablet). Primaquine is contraindicated in children under 1 year and in
pregnant women.
If vomiting precludes oral administration, chloroquine can be given by nasogastric tube.
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*Testing for glucose-6-phosphate dehydrogenase deficiency must be performed before initiation of primaquine, because it can cause hemolytic anemia in such patients.
Malariae malaria cases:
•Chloroquine as a schizonticidal drug.
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•Primaquine as a gametocytocidal drug in a single dose of 0.75 mg/kg following the chloroquine course.
Treatment of P. knowlesi infections:
Based on limited evidence, chloroquine plus sulfadoxine-pyrimethamine should be used
•Patients with any type of malaria must be monitored for possible recrudescence with repeat blood smears at the end of therapy, because recrudescence may occur >90 days after
therapy with low-grade resistant organisms.
•For children living in endemic areas, mothers should be encouraged to seek evaluation for malaria any time the child has a fever.
Clinical Manifestations
🔷 Acquired Toxoplasmosis:
Immunocompetent children who acquire infection postnatally are generally asymptomatic.
When clinical manifestations are apparent, they may include almost any combination of fever, stiff neck, myalgia, arthralgia, maculopapular rash
that spares the palms and soles, localized or generalized lymphadenopathy, hepatomegaly, hepatitis, reactive lymphocytosis, meningitis, brain
abscess, encephalitis, confusion, malaise, pneumonia, polymyositis, pericarditis, pericardial effusion, and myocarditis.
Chorioretinitis symptoms and signs of active ocular infection may be present for a few weeks only or may persist for many months.
The most common manifestation of acute acquired toxoplasmosis is enlargement of 1 or a few cervical lymph nodes. Pectoral, mediastinal,
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mesenteric, and retroperitoneal lymph nodes may be involved. Nodes may be tender but do not suppurate.
DDX include: infectious mononucleosis, lymphoma, or other lymphadenopathies. Involvement of intraabdominal lymph nodes may be
associated with fever, mimicking appendicitis. Lymphadenopathy may wax and wane for as long as 1-2 yr. However, almost all patients with
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lymphadenopathy recover spontaneously without antimicrobial therapy.
Ocular Toxoplasmosis:
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Clinical manifestations include blurred vision, visual floaters, photophobia, epiphora, and, with macular involvement, loss of central vision.
Immunocompromised Persons
Disseminated T. gondii infection among older children who are immunocompromised by AIDS, malignancy, cytotoxic therapy, corticosteroids, or
immunosuppressive drugs given for organ transplantation involves the CNS in 50% of cases and may also involve the heart, lungs, and GI tract.
Typical findings include fever, headache, altered mental status, psychosis, cognitive impairment, seizures, and focal neurologic defects, including
🔷 Treatment of Acquired Toxoplasmosis
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hemiparesis, aphasia, ataxia, visual field loss, cranial nerve palsies, and dysmetria or movement disorders.
Congenital Toxoplasmosis Patients with acquired toxoplasmosis and lymphadenopathy usually do not need specific treatment unless they have severe and persistent symptoms or evidence of damage to vital
Congenital toxoplasmosis usually occurs when a woman acquires primary infection while pregnant. organs.
Treat with pyrimethamine, sulfadiazine, and folinic acid. Therapy often is administered for at least 4-6 wk.
🔷 Etiology:
Toxoplasma gondii multiplies only in living cells.
Most often, maternal infection is asymptomatic or without specific symptoms or signs. As with other adults with acute toxoplasmosis,
lymphadenopathy is the most commonly identified physical finding. 🔷 Diagnosis acute Toxoplasma infection
A loading dose of pyrimethamine for older children is 2 mg/kg/day divided twice daily (maximum 50 mg bid), given for the 1st 2 days of treatment. The maintenance dose
begins on the 3rd day and is 1 mg/kg/day (maximum 50 mg/day). Sulfadiazine is administered at 100 mg/kg/day bid (maximum 4 g/day). Folinic acid (Leucovorin) is administered
In monozygotic twins the clinical pattern of involvement is most often similar, whereas in dizygotic twins the manifestations often differ, including 1) Isolation of T. gondii from blood or body fluids (difficult and requires considerable time)
Toxoplasma gondii, an obligate, intracellular,
Tachyzoites, the pathogenic form of the cases of congenital infection in only 1 twin. 2) Microscopic identification of tachyzoites in sections or preparations of tissues and body fluids, 🔹
orally (PO) at 5-20 mg 3 times weekly (or even daily depending on the leukocyte count).
Side effects of Pyrimethamine:
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parasite in active infections, bradyzoites tissue amniotic fluid, or placenta; identification of cysts in the placenta or tissues of a fetus or newborn; inhibits the synthesis of folic acid, produces a dose-related, reversible, and usually gradual depression of the bone marrow.
protozoan, is acquired perorally, transplacentally, or cysts, remain in tissues, especially the CNS and Congenital infection may present as a mild or severe neonatal disease or the characteristic triad of chorioretinitis, hydrocephalus, and characteristic lymph node histologic features. Reversible neutropenia is the most common adverse effect.
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skeletal and heart muscle, for the life of the and cerebral calcifications.
rarely parenterally in laboratory accidents, 3) Serologic tests are very useful for diagnosis of congenital or acutely acquired Toxoplasma popAll patients treated with pyrimethamine should have leukocyte counts twice weekly. Seizures may occur with overdosage.
🔹 Prognosis
host. Oocysts, another form of the parasite, are More than 50% of congenitally infected infants are considered normal in the perinatal period, but almost all such children will develop ocular infection.
transfusions, or from a transplanted organ. formed in the cat intestine. Cats and other Pathogenesis
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involvement later in life if they are not treated during infancy. 4) Polymerase chain reaction (PCR) is useful to identify T. gondii DNA in CSF and amniotic fluid,infant 🔹
Folinic acid (leucovorin), should be administered concomitantly and for 1 wk after treatment with pyrimethamine is discontinued to prevent bone marrow suppression.
Potential toxic effects of sulfonamides (e.g., crystalluria, hematuria, rash) should be monitored. Hypersensitivity reactions occur, especially in patients with AIDS.
Early institution of specific treatment for congenitally infected infants usually rapidly controls the active
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When the organism is ingested, bradyzoites are released from cysts or sporozoites from oocysts.
Once acquired, latent encysted organisms persist in
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Felidae species are the definitive hosts of T. Systemic Signs peripheral blood and urine to establish the diagnosis definitively. manifestations of toxoplasmosis.
the host throughout life.
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gondii. The organisms enter gastrointestinal (GI) cells, where they multiply, rupture cells, infect contiguous cells,
enter the lymphatics and blood, and disseminate lymphohematogenously throughout the body.
From 25% to >50% of infants with clinically apparent disease at birth are born prematurely. Intrauterine growth restriction, low Apgar scores, and 🔷 Diagnosis of congenital toxoplasmosis
Treatment of Ocular Toxoplasmosis
Treat with pyrimethamine, sulfadiazine, and leucovorin. Systemic corticosteroids administered concomitantly with antimicrobial treatment when lesions involve the macula, optic
Delays in diagnosis and therapy, perinatal hypoglycemia, hypoxia, hypotension, repeated shuntinfections,
In immunologically normal children, acute acquired
Epidemiology:
Tachyzoites proliferate, producing necrotic foci surrounded by a cellular reaction. With development of a
temperature instability are common.
1) Prenatal diagnosis: Fetal ultrasound performed every 2 wk during gestation, beginning at diagnosis nerve head.
🔹 🔹 Currently available treatments do not eradicate encysted parasites.
and severe visual impairment are associated with a poorer prognosis.
Toxoplasmosis
Human infection in older children and adults is Other manifestations may include lymphadenopathy, hepatosplenomegaly, myocarditis, pneumonitis, nephrotic syndrome, vomiting, diarrhea, and
infection most often is asymptomatic or usually acquired orally by eating undercooked
or raw meat that contains cysts or food (e.g.,
normal immune response that is both humoral and cell mediated, tachyzoites disappear from tissues.
In immunocompromised persons and also some apparently immunocompetent persons, acute infection
feeding problems.
Bands of metaphyseal lucency and irregularity of the line of provisional calcification at the epiphyseal plate may occur in the ribs, femurs, and
of acute acquired infection in a pregnant woman, and PCR analysis of amniotic fluid.
2) At birth: T. gondii may also be isolated from the placenta and infant's leukocytes.
Treatment of Immunocompromised Persons
In immunocompromised patients other than those with AIDS, therapy should be continued for at least 4-6 wk beyond complete resolution of all signs and symptoms of active
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🔹 Prevention
unrecognized, but may cause lymphadenopathy or 3) Newborns suspected of having congenital toxoplasmosis should be evaluated by general, Subtopic 1 Counseling pregnant women about the methods of preventing transmission of T. gondii during pregnancy
✳️
progresses and may cause potentially lethal disease.
(Toxoplasma gondii) affect almost any organ.
In immunocompromised persons, initial acquisition or
salad greens) or other material contaminated
with oocysts from acutely infected cats.
Oocysts also may be transported to food by
Congenital Toxoplasmosis
When a mother acquires infection during gestation, organisms may disseminate hematogenously to the
vertebrae. Congenitaltoxoplasmosis may present with hydrops fetalis which confused with erythroblastosis fetalis resulting from isosensitization,
although the Coombs test result is usually negative.
🔹
ophthalmologic, and neurologic examinations; head CT scan; and some or ideally all of the following
tests: lumbar puncture, including analysis of CSF for cells, glucose, protein, Toxoplasma -specific IgG
disease and, if possible, resolution of cause for immune suppression.
AIDS patients treat with antiretroviral treatment plus pyrimethamine and sulfonamides, or TMP-SMX, continued for life.
🔷 Treatment of Congenital Toxoplasmosis:
🔹
can reduce acquisition of infection during gestation.
🔹 Women who do not have specific antibody to T. gondii before pregnancy should only eat well
recrudescence of latent organisms can cause signs flies and cockroaches or may be carried to placenta. Infection may be transmitted to the fetus transplacentally or during vaginal delivery. Of
untreated maternal infections acquired in the first trimester, approximately 17% of fetuses are infected,
Skin
Cutaneous manifestations among newborn infants with congenital toxoplasmosis include rashes and jaundice (due to hepatic involvement and/or 🔻
and IgM antibodies, and level of total IgG; and testing of CSF for T. gondii by PCR and culture.
Presence of Toxoplasma -specific IgM in CSF that is not contaminated with blood, or All fetuses and newborns infected with T. gondii should be treated regardless of whether they have clinical manifestations of infection. The fetus is treated by treating the pregnant 🔹
🔹
cooked meat during pregnancy and avoid contact with cats.
Cats that are kept indoors, maintained on prepared food, and not fed fresh, uncooked meat.
or symptoms related to the central nervous system 🔹
people on the fur of dogs.
Freezing meat to −20°C (−4°F) or heating usually with severe disease. Of untreated maternal infection acquired in the third trimester, approximately
hemolysis) and/or petechiae, ecchymoses and large hemorrhages (secondary to thrombocytopenia). Rashes may be fine punctate, diffuse confirmation of local antibody production of Toxoplasma -specific IgG antibody in CSF, woman. Serologic screening, ultrasound monitoring, and treatment of pregnant women during gestation can also
(CNS) or result in systemic disease. meat to 66°C (150.8°F) renders the tissue cysts 65% of fetuses are infected, usually with disease that is milder or inapparent at birth.
maculopapular, deep blue-red macular, or diffuse blue papular.
Macular rashes involving the entire body including the palms and soles, exfoliative dermatitis, and cutaneous calcifications have been described.
establishes the diagnosis of congenital Toxoplasma infection.
🔷Differential diagnosis (DDX) of congenital toxoplasmosis
Infants should be treated for 1 yr with pyrimethamine (2 mg/kg/day PO bid for 2 days, then beginning on the 3rd day, 1 mg/kg/day for 2 or 6 mo, and then 1 mg/kg given on Monday,
Wednesday, and Friday), sulfadiazine (100 mg/kg/day PO bid), and leucovorin (5-10 mg PO given on Monday, Wednesday, and Friday, or more often depending on neutrophil count). 🔹No protective vaccine is yet available for human use.
reduce the incidence and manifestations of congenital toxoplasmosis.
If untreated, congenital infection usually causes noninfectious.
Toxoplasma organisms are not known to be 🔹
Cyanosis due to interstitial pneumonitis, and edema secondary to myocarditis or nephrotic syndrome may be present.
🔹
🔹 Congenital cytomegalovirus infection
Prednisone (1 mg/kg/day PO bid) has been used in addition when active chorioretinitis involves the macula or otherwise threatens vision, or when the CSF protein is >1,000 mg/dL at
🔹
disease that manifests either perinatally or later in Endocrine Abnormalities birth.
life, most frequently chorioretinitis and CNS lesions.
transmitted from person to person except for
transplacental infection from mother to fetus
May occur 2nd to hypothalamic or pituitary involvement or end-organ involvement but are not common.
🔹 Central Nervous System
🔹
🔹
Neonatal sepsis,
Aseptic meningitis, Treatment of Pregnant Women with Toxoplasma gondii Infection
No treatment for immunologically normal pregnant woman who acquired T. gondii > 6 mo before conception.
and, rarely, by organ transplantation or
transfusion.
Neurologic manifestations of congenital toxoplasmosis vary from massive acute encephalopathy tosubtle neurologic syndromes. Toxoplasmosis
should be considered as a potential cause of any undiagnosed neurologic disease in children <1 yr old, especially if retinal lesions are present.
🔹 Syphilis, or
Hemolytic disease If infection occurs during or shortly before the pregnancy, evaluate the fetus by amniotic fluid PCR and ultrasonography and treat to prevent congenital infection. Spiramycin (1g PO
every 8 hr without food).
Neurologic signs such as convulsions, setting-sun sign with downward gaze, and hydrocephalus (may be the sole clinical neurologic Side effects include: paresthesia, rash, nausea, vomiting, and diarrhea. Note: Pyrimethamine is contraindicated during the first trimester of pregnancy
manifestation) with increased head circumference may be associated with substantial cerebral damage or with relatively mild inflammation For treatment of the pregnant woman whose fetus has a confirmed or probable infection, in the second or third trimester, the combination of pyrimethamine, sulfadiazine, and
obstructing the aqueduct of Sylvius. leucovorin is recommended.
If affected infants are treated and shunted promptly, signs and symptoms may resolve, and development may be normal. Spinal or bulbar Chronically infected pregnant women who are immunocompromised have transmitted T. gondii to their fetuses. Such women should be treated with spiramycin
involvement may be manifested by paralysis of the extremities, difficulty swallowing, and respiratory distress. throughout gestation.
Microcephaly usually reflects severe brain damage.
Untreated congenital toxoplasmosis that is symptomatic in the 1st yr of life can cause substantial diminution in cognitive function (IQ scores of
<70) and developmental delay.
CSF abnormalities occur in at least 50% of infants with congenital toxoplasmosis. A CSF protein level >1 g/dL is characteristic of severe CNS
toxoplasmosis and is usually accompanied by hydrocephalus.
Local production of T. gondii –specific IgG and IgM antibodies may be demonstrated. CT of the brain is useful to detect calcifications (occur
throughout the brain) and determine ventricular size.
Medical treatment in utero and in the 1st yr of life results in improved neurologic outcomes and, in many cases, diminution or disappearance of
calcifications.
🔹 Eyes
Almost all untreated congenitally infected infants develop chorioretinal lesions by adulthood and may have severe visual impairment. Retinal
detachment may occur. Ocular findings also include strabismus, microphthalmia, microcornea, cataracts, nystagmus, glaucoma, optic neuritis,
and optic atrophy. Enucleation has been required for a blind painful eye.
🔹 Ears
Sensorineural hearing loss, both mild and severe, may occur. It is not known whether this is a static or progressive disorder.
Treatment in the 1st year of life decrease the frequency of hearing loss.
by fatema okoff
Prevention (National Malaria Control Programme)
Yemen is classified as high risk area for malaria. Non immune individuals, whether visitors from non-malarious
countries intending to visit Yemen or Yemeni nationals from non malarious areas in Yemen intending to visit
malaria-endemic areas in their country, should take the necessary measures to protect themselves from malaria.
These measures include:
1) Mosquito bite prevention by sleeping under bednet, if possible treated with insectide, and using a mosquito
repellant after sunset.
2) Chemoprophylaxis.
Treatment If possible, travelers should seek medical advice on chemoprophylaxis of malaria. The recommended
Physicians caring for patients with malaria need to be aware of current information regarding malaria because resistance to antimalarial drugs has complicated therapy and drug to be used as chemoprophylaxis for malaria is mefloquine in Yemen; Doxycycline can be used if
prophylaxis. mefloquine is contraindicated. None of the medicine used for chemoprophylaxis provides a 100% protection
Fever without an obvious cause in any patient who has left a P. falciparum– endemic area within 30 days and is nonimmune should be considered a medical emergency. from malaria infection: all fever in travelers to malarious areas should be considered malaria until proven
Thick and thin blood smears should be obtained immediately, and all children with symptoms of severe disease should be hospitalized. If negative, blood films should be repeated otherwise by laboratory examination (microscopy or RDTs).
every 12 hr until 3 smears are documented as negative.
🔶
If the patient is severely ill, antimalarial therapy should be initiated immediately
▪️ Outpatient therapy generally is not given to nonimmune children but may be considered in immune or semi-immune children who have:
▪️
▪️
low-level parasitemia (<1%),
no evidence of complications defined by the World Health Organization (WHO),
▪️
▪️
no vomiting, and a lack of toxic appearance;
who are able to contact the physician or emergency department at any time;
🆘Treatment for Plasmodium Falciparum Malaria (according to national antimalarial program)
and in whom follow-up within 24 hr is ensured.
Complications of Plasmodium Falciparum MALARIA
WHO has identified 10 complications of P. falciparum malaria that define severe malaria.
Pathogenesis 🔷 Severe malarial anemia (hemoglobin level <5 g/dL) is the most common severe complication of malaria in children.
Plasmodium species exist in a variety of forms and have a complex life cycle that enables them to survives
🔹
in different cellular environments in the human host (Asexual phase) and the mosquito (sexual phase).
Two-step process occurs in humans, with the 1st phase in hepatic cells (exoerythrocytic phase) and
Clinical Manifestations 🔹
Anemia is associated with:
🔹 hemolysis
removal of infected erythrocytes by the spleen and impairment of erythropoiesis likely play a greater role than hemolysis in the pathogenesis of severe
the 2nd phase in the RBCs (erythrocytic phase).
🔹
The incubation periods are:
🔹 9-14 days for P. falciparum,
malarial anemia. The primary treatment for severe malarial anemia is blood transfusion.
🔷
🔹 The exoerythrocytic phase begins with inoculation of sporozoites into the bloodstream by a female
🔹 🔹
12-17 days for P. vivax (can be as long as 6-12 mo),
16-18 days for P. ovale, and 18-40 days for P. malariae.
Cerebral malaria is defined as the presence of coma/altered mental status in a child with P. falciparum parasitemia and an absence of other reasons for
coma. Often develops after the patient has been ill for several days but may develop precipitously. Cerebral malaria has a fatality rate of 15–40% and is
🔹
Anopheles mosquito. Within minutes, the sporozoites enter the hepatocytes of the liver, where they associated with:
develop and multiply asexually as a schizont . After 1-2 wk, the hepatocytes rupture and release
🔹
A prodrome lasting 2-3 days is noted in some patients before parasites are detected in the blood.
Prodromal symptoms include headache, fatigue, anorexia, myalgia, slight fever, and pain in the chest, abdomen, and joints.
🔹 long-term cognitive impairment in children.
🔹
thousands of merozoites into the circulation.
The erythrocytic phase of Plasmodium asexual development begins when the merozoites from the
liver penetrate erythrocytes. Once inside the erythrocyte, the parasite transforms into the ring form,
Children with malaria often lack the typical paroxysms in adults (high fever, followed by shaking chills and then diaphoresis) and may have
nonspecific symptoms, including fever (may be low-grade but is often >40°C [104°F]), headache, drowsiness, anorexia, nausea, vomiting, and 🔹 repeated seizures.
hypoglycemia (children with true cerebral malaria fail to arouse from coma even after receivinga dextrose infusion that normalizes their glucose level).
Physical findings may include
🔹
whichthen enlarges to become a trophozoite ,These latter 2 forms can be identified with Giemsa stain on
blood smear, the primary means of confirming the diagnosis of malaria. The trophozoite multiplies
🔹
diarrhea.
While the rupture of schizonts that occurs every 48 hr with P. vivax and P. ovale and every 72 hr with P. malariae can result in a classic pattern
of fevers every other day (P. vivax and P. ovale ) or every 3rd day (P. malariae ), periodicity is less apparent with P. falciparum, and mixed infections
Diagnosis
high fever, seizures, muscular twitching, rhythmic movement of the heador extremities, contracted or unequal pupils, retinal hemorrhages, hemiplegia, absent
or exaggerated deep tendon reflexes, and a positive Babinski sign.
🔷
asexually to produce a number of small erythrocytic merozoites that are released into the bloodstream History and Physical examination -Lumbar puncture reveals increased pressure and mildly increased cerebrospinal fluid protein, typically with no CSF pleocytosis and a normal CSF glucose
🔹
when the erythrocyte membrane ruptures, which is associated with fever.
🔹
and may not be apparent early on in infection, when parasite broods have not yet synchronized.
🔹 Distinctive physical signs may include; splenomegaly (common), hepatomegaly, and pallor as a consequence of anemia. 🔹
Important criteria that suggest P. falciparum malaria include: Malaria retinopathy- funduscopic findings (retinal hemorrhages, peripheral whitening, macular whitening, vessel changes) are relatively specific for cerebral
Over time, some of the merozoites develop into male and female gametocytes that complete the
Plasmodium life cycle when they are ingested during a blood meal by the female anopheline mosquito.
Typical laboratory findings include: anemia, thrombocytopenia, and a normal or low leukocyte count. The erythrocyte sedimentation rate is 🔹
🔹
symptoms occurring <1 mo after return from an endemic area,
>2% parasitemia, 🔹
malaria.
Treatment of cerebral malaria:
Etiology
The male and female gametocytes fuse to form a zygote in the stomach cavity of the mosquito. After a
series of further transformations, sporozoites enter the salivary gland of the mosquito and are inoculated
▪️
often elevated.
P. falciparum is the most severe form of malaria and is associated with higher density parasitemia (as high as 60%) and a number of 🔹 ring forms with double-chromatin dots,
and erythrocytes infected with>1 parasite.
•Antimalarial medications
•Supportive therapy includes: evaluation of and treatment of seizures and hypoglycemia.
Malaria is caused by intracellular Plasmodium
protozoa transmitted to humans by female 🔹
into a new host with the next blood meal
Physiology and pathogenesis in malaria differ according to species:
🔹
complications, in contrast to malaria caused by P. ovale, P. vivax, and P. malariae, which usually result in parasitemias of <2%.
The differences in parasitemia reflect that P. falciparum infects both immature and mature erythrocytes, whereas P. ovale and P. vivax primarily
The diagnosis of malaria is established by identification of organisms on Giemsa-stained smears of
peripheral blood or by rapid immunochromatographic assay (rapid diagnostic test).
•Cerebral edema with increased intracranial pressure is the leading cause of death in children, but treatment with mannitol and corticosteroids has not
improved outcomes in these children.
Malaria is an acute illness characterized by
paroxysms of fever, chills, sweats, fatigue, anemia, 🔹
Anopheles mosquitoes.
Many species of Plasmodium were known to
Infection with all species leads to fever, caused by the host immune response when erythrocytes rupture
and release merozoites into the circulation, and anemia, caused by hemolysis and bone marrow
infect immature erythrocytes and P. malariae infects only mature erythrocytes.
Like P. falciparum, P. knowlesi has a 24 hr replication cycle and can also lead to very high-density parasitemia.
Both thick and thin blood smears should be examined. The concentration of erythrocytes on a thick
smear is 20-40 times that on a thin smear and is used to quickly scan large numbers of
🔷 Respiratory distress is a poor prognostic indicator in severe malaria and appears to be caused by metabolic acidosis rather than intrinsic pulmonary
disease. The primary therapy of malaria appears to be the most effective way to address acidosis.
and splenomegaly. Malaria remains one of the
leading causes of morbidity and mortality
cause malaria in humans:
P. falciparum, P. malariae, P. ovale, P. vivax , 🔹
suppression.
Severe malaria is more common in P. falciparum because of several process, including higher-density
World Health Organization Criteria for Severe Malaria, 2000
1. Impaired consciousness 🔸
erythrocytes.
The thin smear allows for positive identification of the malaria species and determination 🔷 Seizures are a common complication of severe malaria, particularly cerebral malaria.
Malaria (Plasmodium)
2. Prostration Benzodiazepines are first-line therapy for seizures, and intrarectal diazepam has been used successfully in children with malaria and seizures.
▪️
worldwide.
and P. knowlesi
Malaria also can be transmitted through blood
parasitemia, which may lead to excessive production of proinflammatory cytokines; cytoad herence of P.
falciparum -infected erythrocytes to the vascular endothelium; and polyclonal activation, resulting in both 3. Respiratory distress (a result of metabolic acidosis) 🔸
of the percentage of infected erythrocytes and is useful in following the response to therapy.
Although P. falciparum is most likely to be identified from blood just after a febrile Many seizures resolve with a single dose of diazepam. For persistent seizures, phenobarbital or phenytoin are the standard medications used.
Phenytoin may be preferred for seizure treatment, particularly in hospitals or clinics where ventilatory support is not available.
Malarial deaths in areas of high malaria
transmission occur primarily in children <5 yr of age,
transfusion (whole blood, packed red blood
cells (RBCs), platelets, and leukocytes), use of
hypergammaglobulinemia and the formation of immune complexes. Cytoadherence of infected
erythrocytes to vascular endothelium can lead to obstruction of blood flow and capillary damage, with
4. Multiple seizures
5. Jaundice
6. Hemoglobinuria
paroxysm, most children with malaria will have a positive blood smear regardless of the time the
smear is obtained. 🔷 Hypoglycemia is a complication of malaria that is more common in children, pregnant women, and patients receiving quinine therapy. Patients may have
a decreased level of consciousness that can be confused with cerebral malaria.
🔹
contaminated needles, transplacentally from a resultant vascular leakage of blood, protein, and fluid and tissue anoxia. Most guidelines recommend at least 3 -ve blood smears to rule out malaria in children in whom
but in areas of low transmission, a large percentage pregnant woman to her fetus and through Parasite anaerobic metabolism may also lead to hypoglycemia and metabolic acidosis. The 7. Abnormal bleeding malaria is strongly suspected, because low-level parasitemia could potentially go undetected early Any child with impaired consciousness and malaria should have a glucose level checked, and if glucometers are not immediately available, an empirical bolus
of deaths may occur in older children and adults. 8. Severe anemia of dextrose should be given. Hypoglycemia is associated with increased mortality and neurologic sequelae.
organ transplantation.
Epidemiology
cumulative effects of these pathologic processes may lead to cerebral, cardiac, pulmonary, renal, and
hepatic failure.Immunity after Plasmodium sp. infection is incomplete, preventing severe disease but still 9. Circulatory collapse 🔸
in the illness.
Imunochromatographic test for P. falciparum histidine-rich protein (HRP2) and aldolase is 🔷 Circulatory collapse (algid malaria) is a rare complication that manifests as hypotension, hypothermia, rapid weak pulse, shallow breathing, pallor, 🆘Management of severe (complicated) falciparum malaria cases:
Malaria is a major worldwide problem. allowing future infection.
🔹
10. Pulmonary edema
P. vivax malaria is a frequent cause of severe disease and death (caused by severe anemia and sometimes splenic rupture) as P. falciparum in
approved for testing for P. falciparum and P. vivax. Aldolase is present in all 5 of the malaria species and vascular collapse.
🔶 First Option:
🔷
that infect humans. PCR is more sensitive than microscopy but is technically more complex. It is most likely caused by bacterial superinfection, since up to 15% of children in endemic areas with severe malaria may have concurrent bacteremia.
Initial treatment - Artesunate
Repeated episodes of infection occur because the parasite has developed a number of immune-evasive
🔹
some areas.
P. ovale malaria is the least common type of malaria. It is similar to P. vivax malaria and usually is found in conjunction with P. falciparum
Differential Diagnosis includes: Death may occur within hours. Any child with severe malaria and hypotension or hypoperfusion should have a blood culture obtained and should be treated
empirically for bacterial sepsis.
Follow-on treatment - ACT
🔷
strategies, such as intracellular replication, vascular cytoadherence that prevents infected erythrocytes viral infections such as influenza and hepatitis, sepsis, pneumonia, meningitis, encephalitis, Once the patient recovers sufficiently and can tolerate oral treatment, a full ACT should be administered to complete the treatment of the patient.
from circulating through the spleen, rapid antigenic variation, and alteration of the host immune system
🔹
malaria.
P. malariae is the mildest and most chronic of all malaria infections. Nephrotic syndrome is a rare complication of P. malariae infection which
endocarditis, gastroenteritis, pyelonephritis, brucellosis, leptospirosis, tuberculosis, relapsing fever, Long-term cognitive impairment occurs in 25% of children with cerebral malaria and also in children with repeated episodes of uncomplicated Artesunate powder for injection 60 mg:
🔷
resulting in partial immune suppression.
🔹 Resistant malaria in:
🔹
is poorly responsive to corticosteroids.
typhoid fever, yellow fever, viral hemorrhagic fevers, amebic liver abscess, neoplasm, and collagen
vascular disease
disease. Prevention of attacks in these children may improve educational attainment.
🔷 Hyperreactive malarial splenomegaly (HMS) is a chronic complication of P. falciparum malaria in which massive splenomegaly persists after
It should be administered in a dose of 2.4 mg/kg body weight IV or IM given on admission (time = 0), then at 12 h and 24 h, then once daily. As soon as the patient can swallow
provide a full ACT treatment course.
🔹 Erythrocytes containing hemoglobin S (sickle erythrocytes) resist malaria parasite growth.
▪️ P. knowlesi malaria is most often uncomplicated but can lead to severe malaria and death if high-density parasitemia is present.
Recrudescence after a primary attack may occur from the survival of erythrocyte forms in the blood stream. Long-term relapse is caused by
🔹
treatment of acute infection. The vial of Artesunate powder should be mixed with 1 ml of 5% sodium bicarbonate solution (provided) and shaken 2-3 minutes for better dissolution.
🔹 Erythrocytes lacking Duffy blood group antigen are relatively resistant to P. vivax, and
Erythrocytes containing hemoglobin F (fetal hemoglobin) & ovalocytes are resistant to P. falciparum. release of merozoites from an exoerythrocytic source in the liver, which occurs with P. vivax and P. ovale, or from persistence within the
▪️ Major critria include:
🔸
Then,
In hyperendemic areas, newborns rarely become ill with malaria, in part because of passive maternal
▪️
erythrocyte, which occurs with P. malariae and rarely with P. falciparum.
▪️
▪️
splenomegaly (>10 cm),
IgM > 2 SD above local mean, 🔸 1. for IV administration: add 5 ml of 5% glucose or normal saline to make the concentration of artesunate as 10 mg/ml and administer by slow infusion
2. for IM administration: add 2 ml of 5% glucose or normal saline to make the concentration of artesunate as 20 mg/ml
antibody and high levels of fetal hemoglobin.
Children 3 mo to 2-5 yr of age have little specific immunity to malaria species and therefore suffer yearly
Congenital malaria is acquired from the mother prenatally or perinatally. Usually occurs in the offspring of a nonimmune mother with P. vivax
or P. malariae infection, although it can be observed with any of the human malaria species.
▪️ high levels of antibodies to a blood-stage P. falciparum antigen, and
a clinical response to an antimalarial drug. HMS occurs exclusively in children in endemic areas with repeated exposure to malaria and is thought to be
🔶 Second Option: Artemether i.m
attacks of debilitating and potentially fatal disease.
Immunity is subsequently acquired, and severe cases of malaria become less common.
Sign or symptom typically occurs between 10 and 30 days of age (range: 14 hr to several months of age), include fever, restlessness, drowsiness,
▪️
pallor, jaundice, poor feeding, vomiting, diarrhea, cyanosis, and hepatosplenomegaly.
Malaria in pregnancy is a major health problem in malaria endemic countries, can be severe, and is associated with adverse outcomes in the
caused by an impaired immune response to P. falciparum antigens. Prolonged antimalarial prophylaxis (for at least 1 yr, typically with chloroquine, quinine, or
mefloquine) is required to treat this syndrome if the child remains in a malaria endemic area. Spleen size gradually regresses on antimalarial prophylaxis but
🔸
Doses of i.m. artemether and rectal artesunate:Artemether i.m. (intramuscular injection should be given to the anterior thigh):
🔸 Artemether i.m. 3.2 mg / kg divided into two doses in the first day (1.6mg/kg every 12hours in the first day), followed by 1.6 mg / kg daily for the next 6 days; or
Artemether i.m. 3.2 mg / kg divided into two doses in the first day (1.6mg/kg every 12hours in the first day), followed by 1.6 mg / kg daily for at least 3 days (to be the total 4
Both T-cell and antibody responses are important in development of biologic and clinical immunity to often increases again if prophylaxis is stopped.Other complications in children include acute kidney injury and jaundice, both of which are associated with a
fetus or neonate, including intrauterine growth restriction and low birthweight, even in the absence of transmission from mother to child. days of treatment by Artemether i.m), and provide a full treatment course of the first line oral treatment
Plasmodium spp.
Both T-cell and antibody responses are important in development of biologic and clinical
worse outcome and prostration
🔷 Prostration is defined as the inability to sit, stand, or eat without support, in the absence of impairedconsciousness. The pathophysiology of this
🔶
🔸 Third Option: Quinine dihydrochloride injaction for the treatment of severe malaria:
immunity to Plasmodium spp.
🔷
prostration is not well understood.
Uncommon complications include: hemoglobinuria, abnormal bleeding, and pulmonary edema. (Note:pulmonary edema is more frequent in
🔸 Intravenous quinine dihydrochloride should be given by rate-controlled infusion in saline or 5% dextrose solu tions at a rate not exceeding 5 mg salt/kg body weight per hour.
Dose of Quinine for children: 20 mg of salt/kg (loading dose) by IV infusion over 4 hours, then 12 hours after the start of the loading dose give a maintenance dose of quinine, 10
mg salt/kg over 2hours. this repeated every 12 hours, until the patient can swallow, then quinine tablets ,10 mg salt /kg ,8 hourly to complete 7- days course, or quinine IV given for at
adolescents and adults). least 3 days and then shift to the first line (AS+S/P) if the patient can swallow.
•If this is not possible to give quinine by intravenous infusion, then it should be given by intramuscular injection to the anterior thigh, not the buttock (to avoid sciatic nerve injury). The
first dose should be split, 10 mg/kg to each thigh. Undiluted quinine dihydrochloride at a concentration of 300 mg/ml is acidic (pH 2) and painful when given by intramuscular
🔸unitsRecommendations
injection, so it is best either formulated or diluted to concentrations of 60–100 mg/ml for intramuscular injection
for use of antimalarial medicines in remote public health
protozoa Rectal artesunate is the drug of choice for pre-referral treatment of severe malaria in the remote health facilities where health workers do not have access (or cannot
practice) safe intramuscular injections ofartesunate or artemether or quinine Artesunate rectal capsules / suppositories (50 or 200 mg per retocap): 10 mg / kg should be given
rectally as soon as possible, once a diagnosis of severe malaria is made.
continue If the rectal capsule is expelled within the first hour, another rectal capsule should be inserted immediately. A second dose can be repeated after 24 hours.
Supportive therapy is important and may include RBC transfusion(s) to maintain the hematocrit at >20%, supplemental oxygen and ventilatory support for pulmonary
edema or cerebral malaria, careful IV rehydration for severe malaria, IV glucose for hypoglycemia, anticonvulsants for cerebral malaria with seizures, and dialysis for
🔸
renal failure.
Corticosteroids are not recommended for cerebral malaria because they do not improve outcomes.
🆘Treatment of non-falciparum malaria cases
🔹 Vivax and ovale malaria cases:-
-Chloroquine as a schizonticidal drug in a dose of 10mg/kg at the first and second days and then 5mg/kg at the third day.
- Primaquine as an anti-relapse measure in a dose of 0.25 mg/kg daily for 14 days or 0.75 mg/kg weekly for 8 weeks in moderate G6PD deficient patients.
The weekly dose is 3 times the amount indicated for the daily doses. (the strength recommended is 7.5 mg tablet). Primaquine is contraindicated in children under 1 year and in
pregnant women.
If vomiting precludes oral administration, chloroquine can be given by nasogastric tube.
🔹
*Testing for glucose-6-phosphate dehydrogenase deficiency must be performed before initiation of primaquine, because it can cause hemolytic anemia in such patients.
Malariae malaria cases:
•Chloroquine as a schizonticidal drug.
🔹
•Primaquine as a gametocytocidal drug in a single dose of 0.75 mg/kg following the chloroquine course.
Treatment of P. knowlesi infections:
Based on limited evidence, chloroquine plus sulfadoxine-pyrimethamine should be used
•Patients with any type of malaria must be monitored for possible recrudescence with repeat blood smears at the end of therapy, because recrudescence may occur >90 days after
therapy with low-grade resistant organisms.
•For children living in endemic areas, mothers should be encouraged to seek evaluation for malaria any time the child has a fever.
Clinical Manifestations
🔷 Acquired Toxoplasmosis:
Immunocompetent children who acquire infection postnatally are generally asymptomatic.
When clinical manifestations are apparent, they may include almost any combination of fever, stiff neck, myalgia, arthralgia, maculopapular rash
that spares the palms and soles, localized or generalized lymphadenopathy, hepatomegaly, hepatitis, reactive lymphocytosis, meningitis, brain
abscess, encephalitis, confusion, malaise, pneumonia, polymyositis, pericarditis, pericardial effusion, and myocarditis.
Chorioretinitis symptoms and signs of active ocular infection may be present for a few weeks only or may persist for many months.
The most common manifestation of acute acquired toxoplasmosis is enlargement of 1 or a few cervical lymph nodes. Pectoral, mediastinal,
🔻
mesenteric, and retroperitoneal lymph nodes may be involved. Nodes may be tender but do not suppurate.
DDX include: infectious mononucleosis, lymphoma, or other lymphadenopathies. Involvement of intraabdominal lymph nodes may be
associated with fever, mimicking appendicitis. Lymphadenopathy may wax and wane for as long as 1-2 yr. However, almost all patients with
🔹
lymphadenopathy recover spontaneously without antimicrobial therapy.
Ocular Toxoplasmosis:
🔹
Clinical manifestations include blurred vision, visual floaters, photophobia, epiphora, and, with macular involvement, loss of central vision.
Immunocompromised Persons
Disseminated T. gondii infection among older children who are immunocompromised by AIDS, malignancy, cytotoxic therapy, corticosteroids, or
immunosuppressive drugs given for organ transplantation involves the CNS in 50% of cases and may also involve the heart, lungs, and GI tract.
Typical findings include fever, headache, altered mental status, psychosis, cognitive impairment, seizures, and focal neurologic defects, including
🔷 Treatment of Acquired Toxoplasmosis
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hemiparesis, aphasia, ataxia, visual field loss, cranial nerve palsies, and dysmetria or movement disorders.
Congenital Toxoplasmosis Patients with acquired toxoplasmosis and lymphadenopathy usually do not need specific treatment unless they have severe and persistent symptoms or evidence of damage to vital
Congenital toxoplasmosis usually occurs when a woman acquires primary infection while pregnant. organs.
Treat with pyrimethamine, sulfadiazine, and folinic acid. Therapy often is administered for at least 4-6 wk.
🔷 Etiology:
Toxoplasma gondii multiplies only in living cells.
Most often, maternal infection is asymptomatic or without specific symptoms or signs. As with other adults with acute toxoplasmosis,
lymphadenopathy is the most commonly identified physical finding. 🔷 Diagnosis acute Toxoplasma infection
A loading dose of pyrimethamine for older children is 2 mg/kg/day divided twice daily (maximum 50 mg bid), given for the 1st 2 days of treatment. The maintenance dose
begins on the 3rd day and is 1 mg/kg/day (maximum 50 mg/day). Sulfadiazine is administered at 100 mg/kg/day bid (maximum 4 g/day). Folinic acid (Leucovorin) is administered
In monozygotic twins the clinical pattern of involvement is most often similar, whereas in dizygotic twins the manifestations often differ, including 1) Isolation of T. gondii from blood or body fluids (difficult and requires considerable time)
Toxoplasma gondii, an obligate, intracellular,
Tachyzoites, the pathogenic form of the cases of congenital infection in only 1 twin. 2) Microscopic identification of tachyzoites in sections or preparations of tissues and body fluids, 🔹
orally (PO) at 5-20 mg 3 times weekly (or even daily depending on the leukocyte count).
Side effects of Pyrimethamine:
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parasite in active infections, bradyzoites tissue amniotic fluid, or placenta; identification of cysts in the placenta or tissues of a fetus or newborn; inhibits the synthesis of folic acid, produces a dose-related, reversible, and usually gradual depression of the bone marrow.
protozoan, is acquired perorally, transplacentally, or cysts, remain in tissues, especially the CNS and Congenital infection may present as a mild or severe neonatal disease or the characteristic triad of chorioretinitis, hydrocephalus, and characteristic lymph node histologic features. Reversible neutropenia is the most common adverse effect.
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skeletal and heart muscle, for the life of the and cerebral calcifications.
rarely parenterally in laboratory accidents, 3) Serologic tests are very useful for diagnosis of congenital or acutely acquired Toxoplasma popAll patients treated with pyrimethamine should have leukocyte counts twice weekly. Seizures may occur with overdosage.
🔹 Prognosis
host. Oocysts, another form of the parasite, are More than 50% of congenitally infected infants are considered normal in the perinatal period, but almost all such children will develop ocular infection.
transfusions, or from a transplanted organ. formed in the cat intestine. Cats and other Pathogenesis
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involvement later in life if they are not treated during infancy. 4) Polymerase chain reaction (PCR) is useful to identify T. gondii DNA in CSF and amniotic fluid,infant 🔹
Folinic acid (leucovorin), should be administered concomitantly and for 1 wk after treatment with pyrimethamine is discontinued to prevent bone marrow suppression.
Potential toxic effects of sulfonamides (e.g., crystalluria, hematuria, rash) should be monitored. Hypersensitivity reactions occur, especially in patients with AIDS.
Early institution of specific treatment for congenitally infected infants usually rapidly controls the active
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When the organism is ingested, bradyzoites are released from cysts or sporozoites from oocysts.
Once acquired, latent encysted organisms persist in
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Felidae species are the definitive hosts of T. Systemic Signs peripheral blood and urine to establish the diagnosis definitively. manifestations of toxoplasmosis.
the host throughout life.
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gondii. The organisms enter gastrointestinal (GI) cells, where they multiply, rupture cells, infect contiguous cells,
enter the lymphatics and blood, and disseminate lymphohematogenously throughout the body.
From 25% to >50% of infants with clinically apparent disease at birth are born prematurely. Intrauterine growth restriction, low Apgar scores, and 🔷 Diagnosis of congenital toxoplasmosis
Treatment of Ocular Toxoplasmosis
Treat with pyrimethamine, sulfadiazine, and leucovorin. Systemic corticosteroids administered concomitantly with antimicrobial treatment when lesions involve the macula, optic
Delays in diagnosis and therapy, perinatal hypoglycemia, hypoxia, hypotension, repeated shuntinfections,
In immunologically normal children, acute acquired
Epidemiology:
Tachyzoites proliferate, producing necrotic foci surrounded by a cellular reaction. With development of a
temperature instability are common.
1) Prenatal diagnosis: Fetal ultrasound performed every 2 wk during gestation, beginning at diagnosis nerve head.
🔹 🔹 Currently available treatments do not eradicate encysted parasites.
and severe visual impairment are associated with a poorer prognosis.
Toxoplasmosis
Human infection in older children and adults is Other manifestations may include lymphadenopathy, hepatosplenomegaly, myocarditis, pneumonitis, nephrotic syndrome, vomiting, diarrhea, and
infection most often is asymptomatic or usually acquired orally by eating undercooked
or raw meat that contains cysts or food (e.g.,
normal immune response that is both humoral and cell mediated, tachyzoites disappear from tissues.
In immunocompromised persons and also some apparently immunocompetent persons, acute infection
feeding problems.
Bands of metaphyseal lucency and irregularity of the line of provisional calcification at the epiphyseal plate may occur in the ribs, femurs, and
of acute acquired infection in a pregnant woman, and PCR analysis of amniotic fluid.
2) At birth: T. gondii may also be isolated from the placenta and infant's leukocytes.
Treatment of Immunocompromised Persons
In immunocompromised patients other than those with AIDS, therapy should be continued for at least 4-6 wk beyond complete resolution of all signs and symptoms of active
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🔹 Prevention
unrecognized, but may cause lymphadenopathy or 3) Newborns suspected of having congenital toxoplasmosis should be evaluated by general, Subtopic 1 Counseling pregnant women about the methods of preventing transmission of T. gondii during pregnancy
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progresses and may cause potentially lethal disease.
(Toxoplasma gondii) affect almost any organ.
In immunocompromised persons, initial acquisition or
salad greens) or other material contaminated
with oocysts from acutely infected cats.
Oocysts also may be transported to food by
Congenital Toxoplasmosis
When a mother acquires infection during gestation, organisms may disseminate hematogenously to the
vertebrae. Congenitaltoxoplasmosis may present with hydrops fetalis which confused with erythroblastosis fetalis resulting from isosensitization,
although the Coombs test result is usually negative.
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ophthalmologic, and neurologic examinations; head CT scan; and some or ideally all of the following
tests: lumbar puncture, including analysis of CSF for cells, glucose, protein, Toxoplasma -specific IgG
disease and, if possible, resolution of cause for immune suppression.
AIDS patients treat with antiretroviral treatment plus pyrimethamine and sulfonamides, or TMP-SMX, continued for life.
🔷 Treatment of Congenital Toxoplasmosis:
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can reduce acquisition of infection during gestation.
🔹 Women who do not have specific antibody to T. gondii before pregnancy should only eat well
recrudescence of latent organisms can cause signs flies and cockroaches or may be carried to placenta. Infection may be transmitted to the fetus transplacentally or during vaginal delivery. Of
untreated maternal infections acquired in the first trimester, approximately 17% of fetuses are infected,
Skin
Cutaneous manifestations among newborn infants with congenital toxoplasmosis include rashes and jaundice (due to hepatic involvement and/or 🔻
and IgM antibodies, and level of total IgG; and testing of CSF for T. gondii by PCR and culture.
Presence of Toxoplasma -specific IgM in CSF that is not contaminated with blood, or All fetuses and newborns infected with T. gondii should be treated regardless of whether they have clinical manifestations of infection. The fetus is treated by treating the pregnant 🔹
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cooked meat during pregnancy and avoid contact with cats.
Cats that are kept indoors, maintained on prepared food, and not fed fresh, uncooked meat.
or symptoms related to the central nervous system 🔹
people on the fur of dogs.
Freezing meat to −20°C (−4°F) or heating usually with severe disease. Of untreated maternal infection acquired in the third trimester, approximately
hemolysis) and/or petechiae, ecchymoses and large hemorrhages (secondary to thrombocytopenia). Rashes may be fine punctate, diffuse confirmation of local antibody production of Toxoplasma -specific IgG antibody in CSF, woman. Serologic screening, ultrasound monitoring, and treatment of pregnant women during gestation can also
(CNS) or result in systemic disease. meat to 66°C (150.8°F) renders the tissue cysts 65% of fetuses are infected, usually with disease that is milder or inapparent at birth.
maculopapular, deep blue-red macular, or diffuse blue papular.
Macular rashes involving the entire body including the palms and soles, exfoliative dermatitis, and cutaneous calcifications have been described.
establishes the diagnosis of congenital Toxoplasma infection.
🔷Differential diagnosis (DDX) of congenital toxoplasmosis
Infants should be treated for 1 yr with pyrimethamine (2 mg/kg/day PO bid for 2 days, then beginning on the 3rd day, 1 mg/kg/day for 2 or 6 mo, and then 1 mg/kg given on Monday,
Wednesday, and Friday), sulfadiazine (100 mg/kg/day PO bid), and leucovorin (5-10 mg PO given on Monday, Wednesday, and Friday, or more often depending on neutrophil count). 🔹No protective vaccine is yet available for human use.
reduce the incidence and manifestations of congenital toxoplasmosis.
If untreated, congenital infection usually causes noninfectious.
Toxoplasma organisms are not known to be 🔹
Cyanosis due to interstitial pneumonitis, and edema secondary to myocarditis or nephrotic syndrome may be present.
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🔹 Congenital cytomegalovirus infection
Prednisone (1 mg/kg/day PO bid) has been used in addition when active chorioretinitis involves the macula or otherwise threatens vision, or when the CSF protein is >1,000 mg/dL at
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disease that manifests either perinatally or later in Endocrine Abnormalities birth.
life, most frequently chorioretinitis and CNS lesions.
transmitted from person to person except for
transplacental infection from mother to fetus
May occur 2nd to hypothalamic or pituitary involvement or end-organ involvement but are not common.
🔹 Central Nervous System
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Neonatal sepsis,
Aseptic meningitis, Treatment of Pregnant Women with Toxoplasma gondii Infection
No treatment for immunologically normal pregnant woman who acquired T. gondii > 6 mo before conception.
and, rarely, by organ transplantation or
transfusion.
Neurologic manifestations of congenital toxoplasmosis vary from massive acute encephalopathy tosubtle neurologic syndromes. Toxoplasmosis
should be considered as a potential cause of any undiagnosed neurologic disease in children <1 yr old, especially if retinal lesions are present.
🔹 Syphilis, or
Hemolytic disease If infection occurs during or shortly before the pregnancy, evaluate the fetus by amniotic fluid PCR and ultrasonography and treat to prevent congenital infection. Spiramycin (1g PO
every 8 hr without food).
Neurologic signs such as convulsions, setting-sun sign with downward gaze, and hydrocephalus (may be the sole clinical neurologic Side effects include: paresthesia, rash, nausea, vomiting, and diarrhea. Note: Pyrimethamine is contraindicated during the first trimester of pregnancy
manifestation) with increased head circumference may be associated with substantial cerebral damage or with relatively mild inflammation For treatment of the pregnant woman whose fetus has a confirmed or probable infection, in the second or third trimester, the combination of pyrimethamine, sulfadiazine, and
obstructing the aqueduct of Sylvius. leucovorin is recommended.
If affected infants are treated and shunted promptly, signs and symptoms may resolve, and development may be normal. Spinal or bulbar Chronically infected pregnant women who are immunocompromised have transmitted T. gondii to their fetuses. Such women should be treated with spiramycin
involvement may be manifested by paralysis of the extremities, difficulty swallowing, and respiratory distress. throughout gestation.
Microcephaly usually reflects severe brain damage.
Untreated congenital toxoplasmosis that is symptomatic in the 1st yr of life can cause substantial diminution in cognitive function (IQ scores of
<70) and developmental delay.
CSF abnormalities occur in at least 50% of infants with congenital toxoplasmosis. A CSF protein level >1 g/dL is characteristic of severe CNS
toxoplasmosis and is usually accompanied by hydrocephalus.
Local production of T. gondii –specific IgG and IgM antibodies may be demonstrated. CT of the brain is useful to detect calcifications (occur
throughout the brain) and determine ventricular size.
Medical treatment in utero and in the 1st yr of life results in improved neurologic outcomes and, in many cases, diminution or disappearance of
calcifications.
🔹 Eyes
Almost all untreated congenitally infected infants develop chorioretinal lesions by adulthood and may have severe visual impairment. Retinal
detachment may occur. Ocular findings also include strabismus, microphthalmia, microcornea, cataracts, nystagmus, glaucoma, optic neuritis,
and optic atrophy. Enucleation has been required for a blind painful eye.
🔹 Ears
Sensorineural hearing loss, both mild and severe, may occur. It is not known whether this is a static or progressive disorder.
Treatment in the 1st year of life decrease the frequency of hearing loss.
by fatema okoff
