Gross Hematuria in an Elderly Smoker Male Due to Eosinophilic Cystitis.

This is a case of a 71-year-old smoker man who presented with four days of gross hematuria, which turned to be caused by eosinophilic cystitis (EC) proven by bladder biopsy. EC is a rare clinical and pathological inflammatory condition of the bladder with an unknown exact cause. It can present with hematuria, urinary frequency, dysuria, and suprapubic pain. Sometimes, the presentation can mimic urinary tract infection (UTI) or malignancy, especially in older patients.