A young woman presented with abdominal pain that did not get better with empiric antibiotic therapy for presumed urinary tract infection. Renal sonogram revealed bilateral mild to moderate hydronephrosis. There were no stones, but scan of the bladder area revealed a protruding mass with pressure effect on the urinary bladder, which was the likely cause for hydronephrosis. Biopsy of the mass revealed B-cell lymphoma. She was started on chemotherapy and required placement of bilateral nephrostomy tubes for urinary obstruction.

Take home points:

Do not forget to scan the bladder when you see hydronephrosis

In women, always consider pelvic malignancy in addition to urolithiasis when unilateral or bilateral hydronephrosis is detected