Hematuria is commonly seen with infection by which parasite?

• A. Schistosoma haematobium
• B. Schistosoma mansoni
• C. Opisthorchis sinensis
• D. Enterobius vermicularis

Answer: (A)

Hematuria points to urinary schistosomiasis, caused by Schistosoma haematobium. The adult worms live in the venous plexus around the bladder and lay eggs in the bladder wall. The body's immune response to these eggs causes inflammation and ulceration of the bladder mucosa, leading to bleeding into the urine. Clinically, this often presents as painless blood in the urine, especially in people from endemic regions. Eggs from this species are typically found in urine and have a characteristic appearance with a terminal spine. In contrast, Schistosoma mansoni mainly causes intestinal and liver (hepatosplenic) disease with blood in stool rather than urine, Opisthorchis sinensis affects the biliary tract causing liver-related symptoms, and Enterobius vermicularis causes itching around the anus without urinary bleeding.