AMOEBIC DYSENTRY (AMEBIASIS)
INTRODUCTION:
-Invasive intestinal infection with amoeba of the
genus Entamoeba
-Entamoeba histolytica is the common cause of
intestinal amoebiasis
HOW DO WE GET AFFECTED WITH THIS AMOEBA?
There are 2 stage involve here:
1.Cyst stage - "Infective stage"
2.Trophozoite stage - Cause invasive disease
So we get infection from ingestion of "amoebic cysts"
which the infective stage
We can get this from contaminated water/food
From fecal-oral route What does Entamoeba histolytica do
If individual has an infection with Entamoeba to cause this pathogenic scenario ?
histolytica, they will actually release mature
cysts in their feces. 1.E.histolytica secrete proteinases that destroy proteins
Then if another individual comes along & ingests They can go in release these proteinases & destroy proteins in the L.intestinal
contaminated food/water that has been mucosa
contaminated with these cysts, they're going to
get infected themselves. 2.They also can destroy intestinal cells theough a direct-contact mechanism
3.They can also form an Amebapore, which form pores in lipid bilayers of infected
Cysts can survive in environment for weeks - months cells
This basically lyse the cells and cause them to become injured & destroyed
Stages:
4.E.histolytica also can cause tissue damage through disrupting tight junction
1)Cysts ingested proteins, which inventually result in increased intestinal permeability.
2)Then this cysts passes through stomach
3)When the cysts pass through the stomach, they will With all these mechanisms, they can lead to destruction of intestinal tissue which
transform into trophozoites in the small intestine. lead to a bloody diarrhea and also increased secretions , increased intestinal
4)The trophozoites themselves will invade into the permeability
mucosa of Large intestine, and then they start to cause
damage to the tissue and causing increase secretions and
eventually bloody diarrhea.
AMEBIASIS: diagnosis and treatment
AMEBIASIS: CLINICAL FEATURES 1.Stool microscopic examination - Saline mount, iodine mount, trichrome stain fecal
leukocytes
1.Asymptomatic features 2.Immunoserology tests - ELISA test to detect E-histolytica antigen gal lectin
2.Amoebic dysentery 3.Extra-intestinal amoebiasis - Immunoserology tests ; ELISA/IFA/IHT to detect
Dysentery, abdominal pain, colitis antibodies to Gal Lectin
Bloody diarrhea 4.PCR based assays
due to local tissue damage & destruction 5.Culture
3.May also get amoebic abscesses 6.Other - Fecal leukocytes, colonoscopy, histopathology, Ultrasonography, MRI, CT
commonly occur in the liver which is due to scan
hematologic spread AMEBIASIS: TREATMENT
Hepatomegaly
RUQ pain 1.Metronidazole / or can be together with diloxanide.
Weight loss
Fever
This abscesses also can occur in other sites less
commonly than the liver but you can also can
get them in the lungs, brain
INTRODUCTION:
-Invasive intestinal infection with amoeba of the
genus Entamoeba
-Entamoeba histolytica is the common cause of
intestinal amoebiasis
HOW DO WE GET AFFECTED WITH THIS AMOEBA?
There are 2 stage involve here:
1.Cyst stage - "Infective stage"
2.Trophozoite stage - Cause invasive disease
So we get infection from ingestion of "amoebic cysts"
which the infective stage
We can get this from contaminated water/food
From fecal-oral route What does Entamoeba histolytica do
If individual has an infection with Entamoeba to cause this pathogenic scenario ?
histolytica, they will actually release mature
cysts in their feces. 1.E.histolytica secrete proteinases that destroy proteins
Then if another individual comes along & ingests They can go in release these proteinases & destroy proteins in the L.intestinal
contaminated food/water that has been mucosa
contaminated with these cysts, they're going to
get infected themselves. 2.They also can destroy intestinal cells theough a direct-contact mechanism
3.They can also form an Amebapore, which form pores in lipid bilayers of infected
Cysts can survive in environment for weeks - months cells
This basically lyse the cells and cause them to become injured & destroyed
Stages:
4.E.histolytica also can cause tissue damage through disrupting tight junction
1)Cysts ingested proteins, which inventually result in increased intestinal permeability.
2)Then this cysts passes through stomach
3)When the cysts pass through the stomach, they will With all these mechanisms, they can lead to destruction of intestinal tissue which
transform into trophozoites in the small intestine. lead to a bloody diarrhea and also increased secretions , increased intestinal
4)The trophozoites themselves will invade into the permeability
mucosa of Large intestine, and then they start to cause
damage to the tissue and causing increase secretions and
eventually bloody diarrhea.
AMEBIASIS: diagnosis and treatment
AMEBIASIS: CLINICAL FEATURES 1.Stool microscopic examination - Saline mount, iodine mount, trichrome stain fecal
leukocytes
1.Asymptomatic features 2.Immunoserology tests - ELISA test to detect E-histolytica antigen gal lectin
2.Amoebic dysentery 3.Extra-intestinal amoebiasis - Immunoserology tests ; ELISA/IFA/IHT to detect
Dysentery, abdominal pain, colitis antibodies to Gal Lectin
Bloody diarrhea 4.PCR based assays
due to local tissue damage & destruction 5.Culture
3.May also get amoebic abscesses 6.Other - Fecal leukocytes, colonoscopy, histopathology, Ultrasonography, MRI, CT
commonly occur in the liver which is due to scan
hematologic spread AMEBIASIS: TREATMENT
Hepatomegaly
RUQ pain 1.Metronidazole / or can be together with diloxanide.
Weight loss
Fever
This abscesses also can occur in other sites less
commonly than the liver but you can also can
get them in the lungs, brain
