n this report we will present a case on a seventy-six-year-old female patient with bilateral hydronephrosis, sepsis, and insulinoma that died due to septic shock. Necropsy findings showed that the cause of bilateral hydronephrosis was the swelling of the urinary bladder mucosa that occurred due to purulent cystitis which is rare. Interestingly, no obvious predisposing factor in the patient was found. Diabetes mellitus, which is a risk factor for the development of an infection, was not found in our patient, but on the contrary, insulinoma.