Renal allograft rupture has been defined as a split in the renal capsule, associated with haemorrhage, when no identifiable injury was noted at the time of harvesting.
Renal allograft rupture is a rare, but life-threatening, complication of renal allograft placement. It most often occurs in the first two weeks post-transplant and usually requires immediate surgical intervention. The classical presentation is with sudden onset of pain at the graft site, shock and oliguria.
The pathophysiology appears to be secondary to increased intra-renal pressure and and associated secondary injury. The increased pressure can result in splitting of the capsule, usually along the longitudinal outer border, with resultant haemorrhage.
The main putative aetiologies have been described in many case series including this one, and include acute rejection, acute tubular necrosis, renal vein trombosis, increasing PRA, increasing age, biopsy of the graft and infection.
In my quick analysis of published cases series over the last ten years, the crude incidence of RAR appears to be around 1.11%. Of these cases, the majority were caused by acute rejection (55.8%), ATN (34.7%) and renal vein thrombosis (7.4%).
Immediate management involves supportive care and resuscitation, followed by containment of the ruptured area by surgical means or sometimes graft removal. The literature supports an atempt at graft salvage, with many successful outcomes reported to date. Thankfully it remains a relatively rare diagnosis, but definitely one we should all be aware of.