The epidemiology of kidney and urinary tract infections in pediatric chronic kidney disease: prevalence, risk factors and association with GFR decline in the Chronic Kidney Disease in Children Study.

BACKGROUND

Urinary tract and kidney infections are potential complications in pediatric chronic kidney disease (CKD), especially among patients with congenital anomalies of the kidney and urinary tract (CAKUT). We characterized the prevalence of self-reported infections from childhood through young adulthood; evaluated risk factors; and quantified the association with CKD progression.

METHODS

Infections in the past year were self-reported at annual Chronic Kidney Disease in Children (CKiD) study visits. Age-specific infection prevalences were stratified by sex and CKD diagnoses (glomerular, non-glomerular non-CAKUT, CAKUT low-risk for infections, and three CAKUT high-risk categories: reflux nephropathy, obstructive uropathy, and other high-risk). Repeated measures logistic regression quantified associations between infections and clinical variables. Estimated glomerular filtration rate (eGFR) change in the year after infection was assessed using linear regression, adjusted for age, sex, diagnoses, previous year eGFR, medications, and bladder catheterization.

RESULTS

943 participants contributed 4707 person-visits. Among 175 with obstructive uropathy, approximately one-third of boys and two-thirds of girls reported a previous year infection; infection prevalence for other CAKUT diagnoses ranged from about 20% to 50%. Bladder catheterization and history of infections were significantly associated with recent infections. Adjusted eGFR decline in the year after reporting infection was -1.7% faster compared to those free of infection (95%CI: -3.2%, -0.1%, p < 0.05), but this was attenuated when adjusted for catheterization (p = 0.082).

CONCLUSIONS

CAKUT diagnoses were associated with higher infection risk, especially among those with obstructive uropathy, and girls reported more infections than boys. Self-reported infection was significantly associated with accelerated eGFR decline in the following year.