🔷Balantidium coli (B. coli) is the only ciliated protozoan that is known to infect humans. Balantidiasis is a zoonotic disease occurring in humans via the feco-oral route from the normal host, the pig.
🔷Water is the vehicle for most cases. Human-to-human transmission may also occur.
Balantidium’s habitats in humans are the cecum and colon. However, it may be found in rare extraintestinal sites such as liver, lung, and genitourinary tract.B. coli can become an opportunistic parasite in immunosuppressed hosts living in urban environments, where pigs are not a factor in infection. In this case report, B. coli was incidentally found in the urine.
🔷trophozoites of B. coli were detected in urinary sediment examination of an elderly male presenting with urinary tract infection. The parasites were identified by their characteristic morphology and rapid spiraling motility.
🔷Balantidium coli are low virulence pathogenic parasites with worldwide distribution. Usual mode of transmission is ingestion of infective cysts through water contaminated with porcine feces, though human to human transmission may also occur.
🔷Ingested cysts liberate trophozoites which reside and replicate by binary fission in the large bowel (Schuster and Ramirez-Avila 2008).
