AMOEBIASIS & GIARDIASIS

DIAGNOSTIC CRITERIA

Amoebiais

Definition: Infection caused by intestinal protozoan Entameoba Histolytica that spreads by faecaloral route through contaminated food and drink.

1. Recurrent diarrhoea, abdominal cramps, often mucous and rarely blood in stools, stools foul smelling, most patients asymptomatic and ambulant having only occasional loose motions (‘walking dysentery’). Alternating Constipation is common in the chronic case.
2. Perforation, Ileus, peritonitis, haemorrhage, or toxic megacolon in a severe case
3. Hepatic Amoebiasis developing during acute attack or up to 3 months later, with tender hepatomegaly, fever, pain.
4. E.H. trophozoite seen in fresh stool (60% sensitivity in one sample and 90% in three fresh samples) or cyst in stool, or abscess aspirate., In hepatic Amoebiasis - Raised right diaphragm and basal pneumonitis in chest x-ray,/ Abscess imaged by U.S. Scan and C.T.I
5. Positive Serologic test in severe colitis or hepatic disease and this is the diagnostic modality of choice.

Prognosis: Easily treated during acute phase, but very rarely untreated invasive amoebiasis can lead to fatality. Many patients with ameobiasis have features of irritable colon for long periods after therapy.

Giadiasis

Definition An intestianal infection caused by ingestion of the cysts of protozoan Giardia Lamblia t,firough contaminated food and drink.

1. Most are asymptomatic, but could present with diarrhoea of loose to watery consistency, associated flatulence, mucous in stool but no blood,
2. Could be chronic with steatorrhoeic stools, weight loss, nausea, abdominal bloating, and weight loss, and features of malnutrition..
3. Diagnosis by presence of ova and parasite, in examination of fresh motion.

Diagnosis: Giardiasis can be cured with adequate therapy with drugs. Recurrences reflect reinfection, but post-parasitic irritable Bowel Syndrome can occur.

MANAGEMENT

General Principles:

Treated as outpatient. Ideally one should confirm diagnosis by positive stool examination, but often in severe diarrhoeic states, therapeutic diagnosis is required