American Urological Association - Schistosomiasis


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Image A

Image B

  • Infection caused by a water-borne trematode Schistosoma haematobium.
  • Endemic in eastern Mediterranean and sub-Saharan Africa.
  • Infects humans via skin penetration of larvae within water source.
  • Histology:
    • Deposits of round to oval ova with incited chronic inflammation and granuloma formations, and fibrosis with time (image A) & (image B).
    • S. haematobium has terminal spines and lacks acid-fast staining, in contrast to other Schistosoma species.
    • Eggs may calcify overtime.
    • May be associated with keratinizing squamous metaplasia and dysplasia.
  • Risk for development of bladder squamous cell carcinoma.
  • May resemble encrusted cystitis, which in contrast has irregular calcified aggregates.