A malnourished 3-year-old has chronic bloody diarrhoea with tenesmus and growth faltering. During examination a segment of rectum prolapses, revealing numerous whitish worms anchored to the mucosa, each resembling a whip with a thin anterior end. What is the characteristic appearance of the egg of this parasite?

• A Oval with a conspicuous lateral spine
• B Barrel shaped with prominent translucent bipolar plugs ✓
• C Thin shelled and broadly oval, in the four cell stage when passed
• D Flattened on one side, giving a D shape

Explanation

Trichuris trichiura eggs are barrel or football shaped with prominent translucent bipolar mucoid plugs and contain an unsegmented ovum when passed in faeces. Heavy burdens produce chronic dysentery with tenesmus, and rectal prolapse is the classical complication in undernourished children. The D shaped flattened egg belongs to Enterobius vermicularis, the egg with a lateral spine to Schistosoma species, and the thin shelled four cell stage egg to hookworm, killing each distractor.

Reference: Paniker's Textbook of Medical Parasitology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.