[Long-term outcomes of childhood steroid-sensitive nephrotic syndrome]

Abstract

Objective: To investigate the long-term outcomes and risk factors in children with steroid-sensitive nephrotic syndrome (SSNS). Methods: A retrospective cohort study was conducted on newly onset SSNS admitted to the Department of Pediatrics of the First Affiliated Hospital of Sun Yat-sen University from January 2006 to December 2010 and 105 cases with follow-up for more than 10 years were included. Clinical data including general characteristics, clinical manifestation, laboratory tests, treatment and prognosis. The primary outcome was the clinical cure, and the secondary outcomes were relapse or ongoing immunosuppressive treatment within the last 1 year of follow-up and complications at the last follow-up. According to the primary outcome, the patients were divided into clinical cured group and uncured group. Categorical variables were compared between 2 groups using the χ² or Fisher exact test, and continuous variables by t or Mann-Whitney U test. Multiple Logistic regression models were used for multivariate analysis. Results: Of the 105 children with SSNS, the age of onset was 3.0 (2.1, 5.0) years, and 82 (78.1%) were boys, 23(21.9%) were girls. The follow-up time was (13.1±1.4) years; 38 patients (36.2%) had frequently relapsing or steroid-dependent nephrotic syndrome (FRNS or SDNS) and no death or progression to end-stage kidney disease. Eighty-eight patients (83.8%) were clinically cured. Seventeen patients (16.2%) did not reach the clinical cure criteria, and 14 patients (13.3%) had relapsed or ongoing immunosuppressive treatment within the last year of follow-up. The proportion of FRNS or SDNS (12/17 vs. 29.5% (26/88), χ²=10.39), the proportion of treatment with second-line immunosuppressive therapy (13/17 vs. 18.2% (16/88), χ²=21.39), and the level of apolipoprotein A1 at onset ((2.0±0.5) vs. (1.7±0.6) g/L, t=2.02) in the uncured group were higher than those in the clinical cured group (all P<0.05). Multivariate Logistic regression analysis showed that patients treated with immunosuppressive therapy had an increased risk of not reaching clinical cure in the long term (OR=14.63, 95%CI 4.21-50.78, P<0.001). Of the 55 clinically cured patients who had relapsed, 48 patients (87.3%) did not relapse after 12 years of age. The age at last follow-up was 16.4 (14.6, 18.9) years, and 34 patients (32.4%) were ≥18 years of age. Among the 34 patients who had reached adulthood, 5 patients (14.7%) still relapsed or ongoing immunosuppressive treatment within the last year of follow-up. At the last follow-up, among the 105 patients, 13 still had long-term complications, and 8 patients were FRNS or SDNS. The proportion of FRNS or SDNS patients with short stature, obesity, cataracts, and osteoporotic bone fracture was 10.5% (4/38), 7.9% (3/38), 5.3% (2/38), and 2.6% (1/38), respectively. Conclusions: The majority of SSNS children were clinically cured, indicating a favorable long-term prognosis. History of treatment with second-line immunosuppressive therapy was the independent risk factor for patients not reaching the clinical cure criteria in the long term. While it is not uncommon for children with SSNS to persist into adulthood. The prevention and control of long-term complications of FRNS or SDNS patients should be strengthened.