Bilharziasis of urinary bladder and ureter: comparative histopathologic study

Area of Science:

• Uropathology
• Parasitic Diseases
• Oncology

Background:

• Schistosomiasis is a parasitic disease with significant urological manifestations.
• Understanding ova deposition patterns is crucial for elucidating associated pathologies.

Purpose of the Study:

• To compare the incidence and intensity of schistosomiasis oviposition in the urinary bladder and ureter.
• To correlate oviposition sites with histopathological changes, including premalignant lesions.

Main Methods:

• Histopathological examination of urinary bladder and ureter specimens from schistosomiasis patients.
• Analysis of ova deposition sites and severity.
• Documentation of epithelial and premalignant changes.

Main Results:

• Oviposition was heaviest in the urinary bladder submucosa, with lesser involvement in the muscle layer.
• Ureteral oviposition was primarily periureteral and in the outer muscle layer, with minimal submucosal presence.
• Bladder specimens showed more marked epithelial changes (e.g., Brunn nests, cystitis glandularis, squamous metaplasia, papilloma) compared to ureteral specimens.

Conclusions:

• Heavy ova deposition in the bladder submucosa causes mechanical and toxic irritation, leading to premalignant epithelial changes.
• These changes are strongly associated with the high frequency of bladder carcinoma in schistosomiasis patients.
• The ureter exhibits different oviposition patterns and a lower risk for such malignant transformations.