[Renal hemangiomas: a clinical case and review of the literature].

Renal haemangiomas, an unusual cause of renal haematuria, are benign vascular dysplasias of uncertain etiology. Usually asymptomatic, their clinical manifestation is a unilateral renal haematuria associated or not to obstructive urological disease through accumulation of clots in the urinary tract and arterial hypertension when associated to a major arteriovenous shunt. Arteriographic diagnosis is based on the size of the vascular malformation but the absence of findings in the arteriography does not eliminate the presence of small-sized haemangiomas or microhaemangiomas responsible for the renal chronic haematuria, also labelled as "essential haematuria", which sometimes can be diagnosed through endoscopic examination of the renal cavities. This report presents one case of renal haemangioma which appeared as a massive, sudden haematuria and prompted haemodynamic instability requiring haemotherapy. Following arteriographic diagnosis, selective transarterial embolization was undertaken with three modified Gianturco's metal helicoids, to which the patient responded favourably. The report includes a review of the clinical, pathological, diagnostic and therapeutical features of renal haemangiomas.