Context: Few data are available on long-term outcomes among adolescents and young adults with persistent asymptomatic isolated microscopic hematuria.
Objective: To evaluate the risk of end-stage renal disease (ESRD) in adolescents and young adults with persistent asymptomatic isolated microscopic hematuria.
Design, setting, and participants: Nationwide, population-based, retrospective cohort study using medical data from 1,203,626 persons aged 16 through 25 years (60% male) examined for fitness for military service between 1975 and 1997 were linked to the Israeli treated ESRD registry. Incident cases of treated ESRD from January 1, 1980, to May 31, 2010, were included. Cox proportional hazards models were used to estimate the hazard ratio (HR) of treated ESRD among those diagnosed as having persistent asymptomatic isolated microscopic hematuria.
Main outcome measures: Treated ESRD onset, defined as the date of initiation of dialysis treatment or the date of renal transplantation, whichever came first.
Results: Persistent asymptomatic isolated microscopic hematuria was diagnosed in 3690 of 1,203,626 eligible individuals (0.3%). During 21.88 (SD, 6.74) years of follow-up, treated ESRD developed in 26 individuals (0.70%) with and 539 (0.045%) without persistent asymptomatic isolated microscopic hematuria, yielding incidence rates of 34.0 and 2.05 per 100,000 person-years, respectively, and a crude HR of 19.5 (95% confidence interval [CI], 13.1-28.9). A multivariate model adjusted for age, sex, paternal country of origin, year of enrollment, body mass index, and blood pressure at baseline did not substantially alter the risk associated with persistent asymptomatic isolated microscopic hematuria (HR, 18.5 [95% CI, 12.4-27.6]). A substantially increased risk for treated ESRD attributed to primary glomerular disease was found for individuals with persistent asymptomatic isolated microscopic hematuria compared with those without the condition (incidence rates, 19.6 vs 0.55 per 100,000 person-years, respectively; HR, 32.4 [95% CI, 18.9-55.7]). The fraction of treated ESRD attributed to microscopic hematuria was 4.3% (95% CI, 2.9%-6.4%).
Conclusion: Presence of persistent asymptomatic isolated microscopic hematuria in persons aged 16 through 25 years was associated with significantly increased risk of treated ESRD for a period of 22 years, although the incidence and absolute risk remain quite low.