Image Based Question – 74292

The following are images of an intestinal nematode. Which of these are true about it?

A. Transmitted through percutaneous and auto-inoculation

B. Embryonated egg is the infectious stage for this worm

C. The adult worm usually lives in the small intestine

D. Triclabendazole is the drug of choice

Correct Answer » D Explanation

Ans: D. Triclabendazole is the drug of choice

(Ref Paniker’s 7/e p172, 6/e p166; Jawetz 27/e p724; Harrison 19/e p1416)

• Image suggestive of Trichuris trichura.

Forms:

• 2 main forms.

Embryonated forms:

• Egg also present in image.
• Infectious stage.
• Transmitted via oral route.

Adults:

Adult female whipworms:

• Approximately 30-50 mm in length.

Adult male worms:

• Slender anterior end.
• Thicker posterior end.
• Hence appears “buggy whip” → hence name “whipworm”.
• Usually lives in large intestine & appendix.

Life cycle:

• Eggs passed in feces  → Eggs infective after about 3 weeks of incubation in moist & shady soil.
• Humans acquire infection by eating foods contaminated with infective eggs.
• Swallowed eggs → larvae hatch in small intestine → mature & migrate to colon- → Cycle continues.
• DOC: Thiabendazole.