Pseudoaneurysm with severe haematuria in renal allograft after renal biopsy treated by percutaneous embolization

A 61-year-old lady received a cadaveric renal transplant in March 1996. On the seventh post-operative day, a renal allograft biopsy was performed under ultrasound guidance. The patient developed severe haematuria requiring a 2-U blood transfusion. Duplex scanning demonstrated a pseudoaneurysm (2.532.9 cm) at the upper pole of the kidney (Figure 1). Arteriography demonstrated two pseudoaneurysms arising from a cortical artery (Figure 2). These pseudoaneurysms were embolized selectively with four metal coils (Figure 3). There was no further haematuria. The renal biopsy showed evidence of acute tubular necrosis. She underwent two further uneventful transplant biopsies before attaining good renal function. The majority of arteriovenous fistulae and pseudoaneurysms developing after allograft biopsy are either