The long-term outcome of childhood nephrotic syndrome in Germany: a cross-sectional study.

Background: Long-term outcomes of children with nephrotic syndrome have not been well described in the literature.

Methods: Cross-sectional study data analysis of n = 43 patients with steroid-sensitive (SSNS) and n = 7 patients with steroid-resistant (SRNS) nephrotic syndrome were retrospectively collected; patients were clinically examined at a follow-up visit (FUV), on average 30 years after onset, there was the longest follow-up period to date.

Results: The mean age at FUV was 33.6 years (14.4-50.8 years, n = 41). The mean age of patients with SSNS at onset was 4.7 years (median 3.8 years (1.2-14.5 years), the mean number of relapses was 5.8 (0 to 29 relapses). Seven patients (16.3%) had no relapses. Eleven patients were "frequent relapsers" (25.6%) and four patients still had relapses beyond the age of 18 years. Except of cataracts and arterial hypertension, there were no negative long-term outcomes and only one patient was using immunosuppressant therapy at FUV. 55% of patients suffered from allergies and 47.5% had hypercholesterolemia. Two patients suffered a heart attack in adulthood. A younger age at onset (< 4 years) was a risk factor for frequent relapses. An early relapse (within 6 months after onset) was a risk factor and a low birth weight was not a significant risk factor for a complicated NS course. The mean age of patients with SRNS at onset was 4.6 ± 4.4 years and 27.5 ± 9.9 years at FUV. Three patients received kidney transplantations.

Conclusions: The positive long-term prognosis of SSNS can reduce the concern of parents about the probability of the child developing a chronic renal disease during the clinical course after onset.