Proteinuria

EPIDEMIOLOGIC STUDIES of urinary tract disease in healthy children have been few, and have concerned themselves with bacteriuria,¹,²asymptomatic bacteriuria, and pyuria,³,⁴and with the voiding habits of boys.⁵In clinical practice, the routine testing of urine for proteinuria has been the most widely used screening device for urinary tract disease. Yet the magnitude, prevalence, and the persistence of proteinuria has never been prospectively evaluated in healthy children previously screened for urinary tract disease. Much of our knowledge of proteinuria has been borrowed from studies of college, military, and insurance groups incident to routine examination.⁶⁻¹⁰While such studies have considerable merit, they may be criticized on one or more counts: proteinuria is not clearly defined in terms of magnitude, frequency of occurrence, or long-term persistence; urine studies are not complete, but deal only with proteinuria; the study population was not previously screened for urinary tract disease;