[Klippel-Trénaunay syndrome. A rare cause of recurrent macrohematuria: case report].

A 37-year-old man with Klippel-Trénaunay syndrome presented with an episode of painless severe gross hematuria. Magnetic resonance imaging (MRI) revealed vessels of significant diameter in the bladder wall. Diagnostic imaging is mandatory in order to be aware of the extent of the lesion as the bleeding identified intraoperatively may only be the "tip of the iceberg." If conservative means fail, laser coagulation should be the treatment of choice.