Radiological parameters of bleeding renal angiomyolipoma

Angiomyolipomas are rare tumours of the kidney which have a tendency to bleed. We studied the clinical and radiological features of 11 patients from our institution to identify features which may be predictive of a massive haemorrhage. Tumours more than 6 cm in diameter were found to bleed and the demonstration of pseudoaneurysms on contrast CT scanning was associated with massive haemorrhage. We conclude that large angiomyolipomas should be treated to avoid haemorrhage and the detection of pseudoaneurysms should prompt urgent treatment.