Hemodynamically relevant hematuria several months after biopsy of a kidney graft: an unusual cause

We report the case of a 52-year-old female patient, who after a complicated living donor kidney transplantation, underwent kidney biopsy for suspected rejection. Duplex scanning revealed a small, asymptomatic arteriovenous (AV) fistula which was assessed as being hemodynamically unimportant. During follow-up, several urinary tract infections occurred and recurrent short episodes of hematuria were attributed to cystitis, urethritis and urosepsis. Eight months later, the patient developed suddenly massive hematuria, tamponade of the urinary bladder and hemorrhagic shock as well as urosepsis. Duplex sonography showed a massive pseudoaneurysm in addition to the AV fistula. Arteriography confirmed the Duplex sonographic findings and embolization was performed after treatment of concomitant urosepsis. The fistula was closed completely and bleeding ceased. Although AV fistulas are rare complications of kidney biopsies and in most cases they remain asymptomatic, life-threatening hematuria can present several months after a biopsy due to the development of a pseudoaneurysm. Concomitant infectious complications of the urinary tract, bleeding disorders and other factors can be misleading during the assessment of the cause of gross hematuria. Regular Duplex sonographic follow-up examinations in patients with AV fistulas are advisable.