Spontaneous perirenal haematoma secondary to polyarteritis nodosa

Spontaneous perirenal haematoma (SPH) is an unusual but serious complication of polyarteritis nodosa (PAN). We present 3 patients with PAN-associated SPH. One was diagnosed pre-operatively and underwent emergency nephrectomy in order to stop the persistent bleeding; the second patient had surgical drainage of the haematoma and the third recovered without undergoing surgery. The diagnosis is discussed.