Spontaneous perirenal hemorrhage in cauda equina syndrome: a case report.

Neurogenic bladder is a common cause of acute pyelonephritis (APN) in cauda equina syndrome (CES). Perirenal hemorrhage, a rare complication of APN, can be a life-threatening condition. To our knowledge, there is no previous report of perirenal hemorrhage as a complication of APN in CES. A 57-year-old male, diagnosed with CES, due to a L3 burst fracture 3 months earlier, was presented with fever and chills. His diagnosis was APN due to neurogenic bladder. After treatment for APN, he was transferred to the department of rehabilitation medicine for management of his CES. Because of large post-voiding residual urine volumes, he performed self-catheterization after voiding. However, he presented again with fever and chills, and recurrent APN was diagnosed. On the third day of antibiotic treatment, he had acute abdominal pains and hypovolemic shock. Abdominal computed tomography and angiography showed left APN and a perirenal hematoma with left renal capsular artery bleeding. After embolization of the left renal capsular artery, no further active bleeding occurred. Because APN due to neurogenic bladder can lead to critical complications, such as perirenal hemorrhage, the physician should pay attention to the early diagnosis and treatment of urinary tract infection and the management of neurogenic bladder after CES.