Hematuria. A marker of abdominal injury in children after blunt trauma.

The clinical significance of hematuria after blunt trauma was studied in 378 consecutive children evaluated by computed tomography (CT) of the abdomen. Clinical and demographic data, as well as indications for CT (such as hematuria, abdominal tenderness, distention, contusions, and abrasions) were recorded prospectively at the time of CT examination. Hematuria was present in 256 children (68%). Of these, 168 (66%) had microscopic blood (greater than or equal to 10 RBC/HPF), 52 (20%) had a positive dip-stick (less than 10 RBC/HPF), and 36 (14%) had gross hematuria. Both the presence and increasing amount of blood in the urine were associated with significantly higher risk for abdominal injury, multiple organ trauma, and renal injury. Yet when asymptomatic hematuria was the only indication for CT examination, the risk of any abdominal injury was negligible (0 of 41 patients). The presence and severity of hematuria can be useful markers of underlying abdominal injury only in association with other suggestive clinical signs and symptoms. Asymptomatic hematuria is a low-yield indication for abdominal CT in children with blunt abdominal trauma.