Prevalence of Asthma and Allergies and Risk of Relapse in Childhood Nephrotic Syndrome: Insight into Nephrotic Syndrome Cohort.

OBJECTIVE: To determine the lifetime prevalence of allergies in childhood nephrotic syndrome, the seasonality of presentation and relapses, and the impact of allergies on subsequent relapses. STUDY DESIGN: In a longitudinal cohort of children with nephrotic syndrome (ages 1-18 years), assessment for allergic diseases was conducted using the validated and modified version of the International Study of Asthma and Allergies in Childhood questionnaire at enrollment. Outcomes included frequently relapsing nephrotic syndrome, relapse rates, and the relapse-free duration after initial steroid therapy. RESULTS: Among 277 participants, the majority were male (65%) with a median age of 3.7 years (IQR 2.8-5.8) at presentation. A total of 64% reported lifetime allergies with 20% having asthma, 33% wheezing, 27% eczema, and 24% rhinitis. Over 3.3 years of follow-up, presence of asthma and allergies was not associated with frequently relapsing nephrotic syndrome (OR 1.20; 95% CI 0.60, 2.40), higher relapse rates (relative risk 0.95; 95% CI 0.71, 1.27), or risk of first relapse (hazard ratio 1.10; 95% CI 0.83, 1.47) compared with those with no history of allergic diseases. There was also no seasonal variation evident at initial presentation or frequency of relapses. CONCLUSIONS: Two-thirds of children with nephrotic syndrome at presentation have allergic symptoms and asthma; however, neither are associated with an increased frequency of relapses.

Hyperuricemia is associated with hypertension, obesity, and albuminuria in children with chronic kidney disease.

OBJECTIVE: To assess the prevalence and associations of hyperuricemia in a cohort of pediatric patients with chronic kidney disease (CKD). STUDY DESIGN: This was an observational cross-sectional study of clinical and laboratory data in pediatric patients being followed in a nephrology clinic. All patients with CKD were included. ORs and risk estimates of having stage III-V CKD (defined as an estimated glomerular filtration rate [eGFR] <60 mL/min/1.73 m(2)) with hyperuricemia were calculated. The relationships among eGFR, body mass index (BMI), and hyperuricemia were estimated using both correlation and regression models. RESULTS: A total of 116 children (61% male), aged 0.4-17 years, were included in the analysis. The prevalence of hyperuricemia in those with an eGFR <60 mL/min/1.73 m(2) was 70%. Children with hyperuricemia were more likely to have an eGFR <60 mL/min/1.73 m(2) than those with a normal urate level (OR, 4.6) and were more likely to be hypertensive (OR, 2.1). Hyperuricemia was significantly associated with increased BMI, albuminuria, renal dysfunction with reduced eGFR, and hypertension. Significant linear relationships between eGFR and urate (P = .0001) and between BMI and urate (P = .0001) were detected. CONCLUSIONS: Hyperuricemia is common in pediatric patients with CKD and is associated with renal dysfunction, hypertension, obesity, and albuminuria. Future prospective studies should be undertaken to further assess the role of hyperuricemia in pediatric patients with CKD.