Asymptomatic hematuria in childhood: a practical approach to evaluation.

The differential diagnosis of hematuria with or without proteinuria is extensive, and isolated hematuria is a common problem in children and adolescents. Extensive evaluation is often necessary for the child presenting with macroscopic plus microscopic hematuria including nonglomerular and glomerular etiologies, while children with only isolated microscopic hematuria can generally be followed after baseline evaluation to rule out infection, hypercalciuria, familial hematuria, sickle cell disease, post-streptococcal glomerulonephritis (GN), and structural abnormalities (cysts, stones, obstruction, Wilms tumor). Children with the combination of hematuria and proteinuria require rapid systematic evaluation, generally including renal biopsy, except in cases where post-streptococcal GN can be clearly documented. Post-streptococcal GN occurs 7-21 days after a streptococcal infection, is associated with an acute fall in C3 levels with return to normal by approximately 8 weeks, rarely causes acute renal failure, and in children has a pattern of gradual resolution of hypertension, hematuria, and proteinuria over a course of 6-12 months.