AMOEBIASIS

This presentation is made by Dr Ashok Jaisingani for study purpose if any one like this than please give your comments.

1. Amoebiasis Amoebiasis
Dr. Ashok Jaisingani Dr. Ashok Jaisingani

2. Introduction Introduction
►Amoebiasis is caused by Entamoeba histolytica Amoebiasis is caused by Entamoeba histolytica
►The majority of infected individuals are remain The majority of infected individuals are remain
asymptomatic carriers. asymptomatic carriers.
►The mode is via faeco – oral route. The mode is via faeco – oral route.
►Disease occurs as a result of substandard hygiene and Disease occurs as a result of substandard hygiene and
sanitation.sanitation.
►Amoebic liver abscess is the commonest extraintestinal Amoebic liver abscess is the commonest extraintestinal
manifestation, occurs in less than 10%. In endemic areas it manifestation, occurs in less than 10%. In endemic areas it
is much more common than pyogenic abscess. is much more common than pyogenic abscess.
►Pts who are immunocompromised or alcoholic are more Pts who are immunocompromised or alcoholic are more
susceptible to infection. susceptible to infection.

3. Pathogenesis Pathogenesis
►The organisms enter the gut through food and water The organisms enter the gut through food and water
contaminated with cyst. contaminated with cyst.
►In small bowl hatching of cyst result into large number of In small bowl hatching of cyst result into large number of
trophozytes which reached to colon where “Flask Shaped trophozytes which reached to colon where “Flask Shaped
Ulcer” form in the submucosa. Ulcer” form in the submucosa.
►The trophozytes multiply, ultimately forming cyst which The trophozytes multiply, ultimately forming cyst which
enter the portal circulation reach to liver, where they enter the portal circulation reach to liver, where they
multiply in portal triad causing focal infarction of multiply in portal triad causing focal infarction of
hepatocytes and liquificative necrosis (liver abscess), and hepatocytes and liquificative necrosis (liver abscess), and
also passed in the faces as an infective form that infect also passed in the faces as an infective form that infect
other humane being as result of unsanitary conditions. other humane being as result of unsanitary conditions.

4. Amoebic Liver Abscess Amoebic Liver Abscess
►The right lobe is involved in 80% of the cases, the The right lobe is involved in 80% of the cases, the
left in 10% and rest are multiple. left in 10% and rest are multiple.
►The abscess are most common high in The abscess are most common high in
diaphragmatic surface of right lobe, this may diaphragmatic surface of right lobe, this may
cause pulmonary symptoms and chest cause pulmonary symptoms and chest
complication. complication.
►The abscess cavity contain chocolate colored, The abscess cavity contain chocolate colored,
odorless, anchovy sauce – like fluid that is mixture odorless, anchovy sauce – like fluid that is mixture
of the necrotic liver tissue and blood.of the necrotic liver tissue and blood.
►Untreated abscess are likely to be rupture. While Untreated abscess are likely to be rupture. While
pus in abscess is sterile unless secondarily infected pus in abscess is sterile unless secondarily infected

5. Chronic Amoebic Infection Of Large Chronic Amoebic Infection Of Large
BowlBowl
►Chronic Infection of large bowl may result Chronic Infection of large bowl may result
into granulomatous lesion along the large into granulomatous lesion along the large
bowl, most commonly seen in caecum called bowl, most commonly seen in caecum called
as “Amoeboma” as “Amoeboma”

6. Clinical Features Clinical Features
►Typical pts with amoebic liver disease is young adult male Typical pts with amoebic liver disease is young adult male
with history of “Pain and fever” with insidious onset of non with history of “Pain and fever” with insidious onset of non
– specific symptoms – specific symptoms
- Anorexia - Anorexia
- Night Sweats - Night Sweats
- Malaise - Malaise
- Cough - Cough
►Then gradually more specific symptoms such as Then gradually more specific symptoms such as
1- Pain in right upper abdomen, shoulder tip pain 1- Pain in right upper abdomen, shoulder tip pain
2- Hicoughs2- Hicoughs
3- Non – productive cough 3- Non – productive cough
►There may also be past history of bloody diarrhea or travel There may also be past history of bloody diarrhea or travel
to endemic areas raise the suspicious index. to endemic areas raise the suspicious index.

7. Clinical Examination Clinical Examination
►Examination reveals pt who is toxic and anemic Examination reveals pt who is toxic and anemic
► Pt will have upper abdominal rigidity Pt will have upper abdominal rigidity
►Hepatomegaly Hepatomegaly
►Tender & bulging intercostal space Tender & bulging intercostal space
►Overlying skin edema Overlying skin edema
►Pleural Effusion Pleural Effusion
►Basal pneumonitis (usually late manifestation) Basal pneumonitis (usually late manifestation)
►There may be jaundice or ascites also presentThere may be jaundice or ascites also present
►Rarely there may be rupture of abscess cavity into Rarely there may be rupture of abscess cavity into
peritoneum, pleural space or pericardial cavity and pts peritoneum, pleural space or pericardial cavity and pts
present as an emergency. present as an emergency.

8. How To Differentiate Amoeboma How To Differentiate Amoeboma
From Right Sided Colon Cancer?From Right Sided Colon Cancer?
►An amoeboma should be suspected when a An amoeboma should be suspected when a
patient from endemic area with generalized patient from endemic area with generalized
ill health and pyrexia have a mass in right ill health and pyrexia have a mass in right
iliac fossae, with history of blood stained iliac fossae, with history of blood stained
mucoid diarrhea. mucoid diarrhea.
►Such type of pts is highly unlikely to have Such type of pts is highly unlikely to have
carcinoma as “altered bowl habit” is not carcinoma as “altered bowl habit” is not
feature of right sided colon cancer. feature of right sided colon cancer.

9. Investigation Investigation
►Haematological Tests Haematological Tests
►Biochemical Tests Biochemical Tests
►Serological Tests (more specific to detect antibodies) are Serological Tests (more specific to detect antibodies) are
1- Test for compliment fixation1- Test for compliment fixation
2- Indirect haemagglutination assay (IHA) 2- Indirect haemagglutination assay (IHA)
3- Indirect Immunoflourescence3- Indirect Immunoflourescence
4- Enzyme – like Immunosorbent assay (ELISA) 4- Enzyme – like Immunosorbent assay (ELISA)
►IHA has very high sensitivity rate in acute amoebic liver IHA has very high sensitivity rate in acute amoebic liver
abscess in non – endemic region and remain elevated for abscess in non – endemic region and remain elevated for
some time. some time.
►An outpatient rigid sigmoidoscopy using disposable An outpatient rigid sigmoidoscopy using disposable
instrument is very useful particularly if pts complain bloody instrument is very useful particularly if pts complain bloody
mucoid diarrhea. mucoid diarrhea.

10. Haemetological & Biochemical Tests Haemetological & Biochemical Tests
►These investigation reflects the presence of These investigation reflects the presence of
chronic infective process with chronic infective process with
1- Anemia 1- Anemia
2- Leucocytosis 2- Leucocytosis
3- Elevated ESR 3- Elevated ESR
4- Elevated C – reactive protein 4- Elevated C – reactive protein
5- Hypoalbunaemia 5- Hypoalbunaemia
6- Deranged Liver Function Test 6- Deranged Liver Function Test
7- Elevated alkaline phosphate 7- Elevated alkaline phosphate

11. Sigmoidoscopy Sigmoidoscopy
►Sigmoidoscopy show shallow skip lesion and Sigmoidoscopy show shallow skip lesion and
flask shaped or “collar – stud” undermine flask shaped or “collar – stud” undermine
ulcer may be seen and can be biopsied or ulcer may be seen and can be biopsied or
scraping can be taken along with mucus for scraping can be taken along with mucus for
microscopic examination. microscopic examination.
►Presence of trophozoites distinguish the Presence of trophozoites distinguish the
condition from ulcerative collitis. condition from ulcerative collitis.

12. Imaging TechniqueImaging Technique
►Ultrasound and CT – scan are the imaging Ultrasound and CT – scan are the imaging
method of the choice.method of the choice.
►Ultrasound investigation is very accurate Ultrasound investigation is very accurate
and is used for aspiration, both diagnostic and is used for aspiration, both diagnostic
and therapeutic purpose. and therapeutic purpose.
►Doubtful cases CT – scan confirm the Doubtful cases CT – scan confirm the
diagnosis. diagnosis.

13. Amoebic TreatmentAmoebic Treatment
►Medical treatment is very effective should be first choice.Medical treatment is very effective should be first choice.
►Metronidazole and tinidazole are effective drugsMetronidazole and tinidazole are effective drugs
►Diloxanide furoate, not effective against hepatic infestation is used for Diloxanide furoate, not effective against hepatic infestation is used for
10 days to destroy intestinal amoeba 10 days to destroy intestinal amoeba
►In large abscess repeated aspiration is combined with drug treatment, In large abscess repeated aspiration is combined with drug treatment,
threshold for aspiring abscess in left lobe is lower because its threshold for aspiring abscess in left lobe is lower because its
predilection for rupturing into pericardium. predilection for rupturing into pericardium.
►Surgical treatment reserve for the complication such as rupture into Surgical treatment reserve for the complication such as rupture into
pleural, peritoneal or pericardial cavity. pleural, peritoneal or pericardial cavity.
►Resuscitation, Drainage and appropriate lavage with vigorous medical Resuscitation, Drainage and appropriate lavage with vigorous medical
treatment are key principles. treatment are key principles.
►Acute toxic megacolon and hemorrhage are intestinal complication that Acute toxic megacolon and hemorrhage are intestinal complication that
are treated with intensive supportive therapy followed by resection and are treated with intensive supportive therapy followed by resection and
exteriorisation. exteriorisation.
►When an amoeboma is suspected in a colonic mass cancer should be When an amoeboma is suspected in a colonic mass cancer should be
excluded by appropriate imaging. excluded by appropriate imaging.