Answer 43
Giardiasis
True a. can be diagnosed by duodenal biopsy
False b. leaves the small bowel morphologically normal
False c. has an incubation period of less than 48 hours
True d. causes abdominal distension
True e. usually responds to treatment with metronidazole
Diagnosis is usually made by finding Giardia lamblia cysts in the stool. Other useful diagnostic techniques include: duodenal biopsy, microscopy of duodenal aspirate and enzyme immunoassay for Giardia antigens in the stool.
Histologically small bowel villi and microvilli may be shortened. These changes are not diagnostic.
The incubation period is usually greater than 48 hours.
Characteristic clinical features include: weight loss, diarrhoea, steatorrhoea, flatulence and abdominal distension.
Metronidazole is the usual treatment.
