Colonic taeniasis

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A 52-year-old Tibetan male was referred for evaluation of rectal bleeding and intermittent mid abdominal pain. He reported frequent loose stools but no associated fever or weight loss. Results from physical exam were within normal limits. Hemoglobin level was 13.1 g/dL (normal range 14 – 18 g/dL), and white-cell count was 5100/mm³ (normal 4800 – 10 800/mm³) with 13 % eosinophils (normal 1 % – 4 %). Colonoscopy revealed small nonbleeding internal hemorrhoids, and a white ribbon-like structure protruding from the ileocecal valve ([Fig. 1]) and extending throughout the entire colon ([Fig. 2]). A segment of the mobile worm was successfully removed using biopsy forceps, and histologic evaluation demonstrated parasite eggs morphologically consistent with Taenia spp. ([Fig. 3], [Video 1]).

Fig. 1 Flat, white, mobile worm emerging from ileocecal valve.

Fig. 2 Extension of worm through transverse colon.

Fig. 3  Taenia spp. eggs. Original magnification × 40.

Video 1 Mobile tapeworm moving in colon and grabbed with forceps.

Taenia solium and T. saginata are the most common species of tapeworms infecting humans. Although the worm normally resides in the small intestine it can grow up to 25 m and extend into the large intestine. The patient was treated successfully with one dose of praziquantel.

Endoscopy_UCTN_Code_CCL_1AD_2AZ