Sport hematuria in boys: a provocative test.

Sports hematuria has been described in adult athletes. We report on two boys with gross hematuria after soccer matches. Urinalysis was negative for hematuria at the first visit. A simple test of effort provoked the phenomenon and allowed the detection of the post-renal origin of bleeding and the rapid resolution of hematuria. Such a test may be particularly helpful after the first episode, when it is problematic to postulate a cause-effect relationship between exercise and hematuria on the basis of the patients' history.