Infectious Diseases
Recognised features of infectious mononucleosis include:
A Palatal petechial haemorrhages (True)
B Aseptic meningitis (True)
C Vesicular rash on neck and trunk (False)
D Raised asparatate amino transferase (True)
E Splenomegaly (True)
Comments:
Incubation period of infectious mononucleosis is 30-60 days. Results of infection:
1. Asymptomatic (most)
2. Simple infection: fever, malaise, headache, myalgia, worsening sore throat
abdominal pain. Splenic enlargement in 50% to 2-3cm. 90% have
lymphadenopathy and 10% liver enlargement. Severe pharyngitis with exudate
and petechiae is often present, and maculopapular rash will occur in 80% given
Amoxycillin.
3. Complications:
• Splenic rupture with trauma (<0.2%).
• Stridor or respiratory distress, which may be treated with steroids.
• CNS: ataxia, fits, Alice in Wonderland Syndrome, Guillain Barre.
• Haematology: Haemolytic anaemia, aplastic anaemia.
• Other: Myocarditis, intesitial pneumonitis, pancreatitis, parotitis and orchitis.
Copyright © 2002 Dr Colin Melville
BCG vaccination:
A is contraindicated in neonates (False)
B is a killed polysaccharide antigen vaccine (False)
C should be given to all children who have a strongly positive
(False)
tuberculin test
D is presently routinely offered in the UK at age 16 years (False)
E also provides protection against leprosy (True)
,Comments:
a - BCG vaccine may given to newborns at high risk of exposure. b - The BCG vaccine
is an attenuated strain - it provides approximately 70% protection. c - It should NOT
be given to these children. A low reactivity Heaf test (grade 0 - 1) should be
documented before administration. d- BCG is given at Comprehensive school entry
(age 11 - 13). e - It has also found a use in stimulating the immune system for the
treatment of some cancers.
Presenting features of HIV infection in childhood include:
A Persistent oral thrush beyond the neonatal period (True)
B Hepatosplenomegaly (True)
C Failure to thrive (True)
D Bilateral perihilar infiltrates on chest x-ray (True)
E Recurrent otitis media (True)
Comments:
Post-neonatal thrush suggests cell-mediated immune deficiency if the child has not had
broad-spectrum antibiotics. Hepatosplenomegaly and lymphadenopathy are
characteristic. Lymphoid interstitial pneumonitis (LIP) is a common finding,
particularly in Africans. Recurrent common bacterial infections occur in early disease,
with pneumocystic pneumonia, pneumococcal septicaemia being disseminated CMV
making further decline in their immunity.
Copyright © 2002 Dr Colin Melville
Clinical features of toxoplasmosis include:
A microcephaly (True)
B choroidoretinitis (True)
C cervical lymphadenopathy (True)
D mouth ulcers (False)
E sacroiliitis (False)
Comments:
,Causes for Microcephaly include; * down's syndrome * congenital rubella * congenital
toxoplamosis * congenital CMV * cri du chat syndrome * seckel'syndrome *
rubinstein-taybi syndrome * trisomy 13 * trisomy 18 * smith-lemli-opitz syndrome *
cornelia de Lange syndrome * uncontrolled maternal phenylketonura * methylmercury
poisoning
The following are features of congenital toxoplasmosis:
A Generalised lymphadenopathy (True)
B Microcephaly (True)
C Thrombocytopenia (True)
D Intracranial calcification (True)
E A good prognosis without treatment (False)
Comments:
Congenital toxoplasmosis, fortunately rare, is associated with the usual manifestations
of congenital infection: IUGR, thrombocytopaenia, intracranial calcification,
chorioretinitis. Hydrocephalus is more common, but microcephaly well described.
Most cases are unaffected, but may present with chorioretinitis many years later. The
incidence used to be highest in France, because of their penchant for eating uncooked
meat, but public health measures have reduced the incidence there. Copyright © 2002
Dr Colin Melville
IgA:
A Is involved in mucosal immunity. (True)
B Have 4 distinct sub-groups. (False)
C Activates complement via the classical pathway. (False)
D Is manufactured in lymph nodes. (True)
E Crosses the placenta. (False)
Comments:
IgA is the major antibody in serology: tears, sweat, lung, gut, urine. IgA avoids
digestion by the presence of the secretory piece which is added as it is secreted onto
the mucosa. It is an important defence
, against surface binding of micro-organisms. There are 2 sub-types, IgA1 and IgA2.
Only IgG is transferred across the placenta. Complement proteins circulate, therefore,
they rarely come into contact with IgA.
Copyright © 2002 Dr Colin Melville
In ataxia telangiectasia:
A Inheritance is X-linked recessive. (False)
B The usual presentation is with lower respiratory infections. (False)
C Chromosome fragility is increased. (True)
D The immunodeficiency primarily affects phagocyte function. (False)
E Chronic thrombocytopenia is an important feature. (False)
Comments:
Ataxia telangiectasia is an autosomal recessive disorder, with a defect that has now
been localised to chromosome 11q 22-23. Ataxia occurs when a child first begins to
walk, and subsequently, recurrent sino-pulmonary infections occur. Telangiectasiae
become evident at 3-6 years, because of the DNA repair defects (similar defects are
found in Fanconi's anaemia and Bloom's Syndrome). The immune deficiency is
variable, with the commonest being an IgA deficiency. Thrombocytopenia suggests
Wiskott-Aldrich Syndrome, particularly in a boy with immune deficiency and eczema.
Copyright © 2002 Dr Colin Melville
The following conditions are thought to have an atopic basis:
A Seborrhoeic dermatitis (False)
B Dermatitis in response to nickel (False)
C Anaphylactic reaction to peanuts (True)
D Hereditary angio-neurotic oedema (False)
E Cow's milk protein intolerance (True)
Comments:
Seborrhoeic dermatitis is a condition of unknown aetiology, and is associated with
Recognised features of infectious mononucleosis include:
A Palatal petechial haemorrhages (True)
B Aseptic meningitis (True)
C Vesicular rash on neck and trunk (False)
D Raised asparatate amino transferase (True)
E Splenomegaly (True)
Comments:
Incubation period of infectious mononucleosis is 30-60 days. Results of infection:
1. Asymptomatic (most)
2. Simple infection: fever, malaise, headache, myalgia, worsening sore throat
abdominal pain. Splenic enlargement in 50% to 2-3cm. 90% have
lymphadenopathy and 10% liver enlargement. Severe pharyngitis with exudate
and petechiae is often present, and maculopapular rash will occur in 80% given
Amoxycillin.
3. Complications:
• Splenic rupture with trauma (<0.2%).
• Stridor or respiratory distress, which may be treated with steroids.
• CNS: ataxia, fits, Alice in Wonderland Syndrome, Guillain Barre.
• Haematology: Haemolytic anaemia, aplastic anaemia.
• Other: Myocarditis, intesitial pneumonitis, pancreatitis, parotitis and orchitis.
Copyright © 2002 Dr Colin Melville
BCG vaccination:
A is contraindicated in neonates (False)
B is a killed polysaccharide antigen vaccine (False)
C should be given to all children who have a strongly positive
(False)
tuberculin test
D is presently routinely offered in the UK at age 16 years (False)
E also provides protection against leprosy (True)
,Comments:
a - BCG vaccine may given to newborns at high risk of exposure. b - The BCG vaccine
is an attenuated strain - it provides approximately 70% protection. c - It should NOT
be given to these children. A low reactivity Heaf test (grade 0 - 1) should be
documented before administration. d- BCG is given at Comprehensive school entry
(age 11 - 13). e - It has also found a use in stimulating the immune system for the
treatment of some cancers.
Presenting features of HIV infection in childhood include:
A Persistent oral thrush beyond the neonatal period (True)
B Hepatosplenomegaly (True)
C Failure to thrive (True)
D Bilateral perihilar infiltrates on chest x-ray (True)
E Recurrent otitis media (True)
Comments:
Post-neonatal thrush suggests cell-mediated immune deficiency if the child has not had
broad-spectrum antibiotics. Hepatosplenomegaly and lymphadenopathy are
characteristic. Lymphoid interstitial pneumonitis (LIP) is a common finding,
particularly in Africans. Recurrent common bacterial infections occur in early disease,
with pneumocystic pneumonia, pneumococcal septicaemia being disseminated CMV
making further decline in their immunity.
Copyright © 2002 Dr Colin Melville
Clinical features of toxoplasmosis include:
A microcephaly (True)
B choroidoretinitis (True)
C cervical lymphadenopathy (True)
D mouth ulcers (False)
E sacroiliitis (False)
Comments:
,Causes for Microcephaly include; * down's syndrome * congenital rubella * congenital
toxoplamosis * congenital CMV * cri du chat syndrome * seckel'syndrome *
rubinstein-taybi syndrome * trisomy 13 * trisomy 18 * smith-lemli-opitz syndrome *
cornelia de Lange syndrome * uncontrolled maternal phenylketonura * methylmercury
poisoning
The following are features of congenital toxoplasmosis:
A Generalised lymphadenopathy (True)
B Microcephaly (True)
C Thrombocytopenia (True)
D Intracranial calcification (True)
E A good prognosis without treatment (False)
Comments:
Congenital toxoplasmosis, fortunately rare, is associated with the usual manifestations
of congenital infection: IUGR, thrombocytopaenia, intracranial calcification,
chorioretinitis. Hydrocephalus is more common, but microcephaly well described.
Most cases are unaffected, but may present with chorioretinitis many years later. The
incidence used to be highest in France, because of their penchant for eating uncooked
meat, but public health measures have reduced the incidence there. Copyright © 2002
Dr Colin Melville
IgA:
A Is involved in mucosal immunity. (True)
B Have 4 distinct sub-groups. (False)
C Activates complement via the classical pathway. (False)
D Is manufactured in lymph nodes. (True)
E Crosses the placenta. (False)
Comments:
IgA is the major antibody in serology: tears, sweat, lung, gut, urine. IgA avoids
digestion by the presence of the secretory piece which is added as it is secreted onto
the mucosa. It is an important defence
, against surface binding of micro-organisms. There are 2 sub-types, IgA1 and IgA2.
Only IgG is transferred across the placenta. Complement proteins circulate, therefore,
they rarely come into contact with IgA.
Copyright © 2002 Dr Colin Melville
In ataxia telangiectasia:
A Inheritance is X-linked recessive. (False)
B The usual presentation is with lower respiratory infections. (False)
C Chromosome fragility is increased. (True)
D The immunodeficiency primarily affects phagocyte function. (False)
E Chronic thrombocytopenia is an important feature. (False)
Comments:
Ataxia telangiectasia is an autosomal recessive disorder, with a defect that has now
been localised to chromosome 11q 22-23. Ataxia occurs when a child first begins to
walk, and subsequently, recurrent sino-pulmonary infections occur. Telangiectasiae
become evident at 3-6 years, because of the DNA repair defects (similar defects are
found in Fanconi's anaemia and Bloom's Syndrome). The immune deficiency is
variable, with the commonest being an IgA deficiency. Thrombocytopenia suggests
Wiskott-Aldrich Syndrome, particularly in a boy with immune deficiency and eczema.
Copyright © 2002 Dr Colin Melville
The following conditions are thought to have an atopic basis:
A Seborrhoeic dermatitis (False)
B Dermatitis in response to nickel (False)
C Anaphylactic reaction to peanuts (True)
D Hereditary angio-neurotic oedema (False)
E Cow's milk protein intolerance (True)
Comments:
Seborrhoeic dermatitis is a condition of unknown aetiology, and is associated with
