Significant renal hemorrhage following extracorporeal shock wave lithotripsy: imaging and clinical features.

Extracorporeal shock wave lithotripsy (ESWL), either alone or in combination with percutaneous or retrograde techniques, has rapidly become the procedure of choice for the treatment of intrarenal and upper ureteral calculi. Complications have been few so far and usually have been urinary obstructions or hemorrhages. Most fluid collections observed after ESWL are asymptomatic and their detection usually does not prolong hospitalization or alter therapy. In five patients out of 2,149 patient treatments symptomatic renal hematomas developed within a few hours after ESWL for renal calculi. In two of these patients the partial thromboplastin time was mildly prolonged. In four patients blood volume replacement was required to treat a falling hematocrit reading or hypotension. Diagnosis of the hematomas was initially made with sonography, although computed tomography and magnetic resonance imaging were used to further define the distribution and extent of retroperitoneal hematomas. Severe ipsilateral flank pain and rapid decrease in the hematocrit reading after ESWL strongly suggest significant bleeding from the treated kidney and require prompt radiologic confirmation and careful clinical treatment until there is evidence that the hemorrhage has stopped.