Extramedullary chronic lymphocytic leukemia disguised as urinary tract infection.

Extramedullary and nonlymphoid organ involvement in chronic lymphocytic leukemia (CLL) is exceedingly rare, with only a few cases of bladder infiltration reported to date. Here, we present a case of a 71-year-old man with advanced-stage CLL who presented with gross hematuria initially thought to be secondary to a urinary tract infection. However, a cystoscopy with biopsy confirmed the diagnosis of extramedullary CLL with bladder involvement. The patient was started on venetoclax with improvement in symptoms and no recurrence of hematuria.