Spectrum of childhood nephrotic syndrome in Iran: A single center study

Nephrotic syndrome (NS) is a clinical entity characterized by massive loss of urinary protein (primarily albuminuria) leading to hypoproteinemia (hypoalbuminemia) and its result, edema. Hyperlipidemia, hypercholesterolemia, and increased lipiduria are usually associated. Although not commonly thought of as part of the syndrome, hypertension, hematuria, and azotemia may be present. This prospective cross-sectional study was performed on 44 children (with age of onset up to 14 years) with idiopathic nephrotic syndrome (INS) in our center during 2000-2007. The objectives were to study the clinical and biochemical parameters and the histopathological distribution of different subtypes of INS and drug-response pattern in these patients. The study group included 44 children. There were 29 (66%) boys and 15 girls (34%). The mean age was 4.87 +/- 3.24 years. Facial edema was found in 42 (95%), microscopic hematuria in 10 (23%), gross hematuria in 2 (4.5%), and hypertension in 5 (11.2%) patients. In children who underwent biopsy, focal segmental glomerulosclerosis was the most common pathologic finding (41%). Other subtypes included minimal change disease in three (18%), membranoproliferative glomerulonephritis in one (5.8%), diffuse proliferative glomerulonephritis in two (11.6 %), membranous glomerulonephritis in one (5.8%), and diffuse mesangial proliferation in three (17.5%) cases. At the time of hospitalization peritonitis was present in five (11.4%), pneumonia and upper respiratory infection (sinusitis) in eight (18%), and cellulites in two (4.5%) patients. Twenty nine patients (66%) were steroid sensitive, 9 (20.5%) steroid resistant, and 6 (13.5%) steroid dependent. Among patients with steroid-sensitive NS, 37% were nonrelapsers, 38.8% frequent relapsers, and 26.4% were infrequent relapsers. Differences seems to exist between season of incidence, suitable response to treatment with corticosteroids, and pathologic findings of biopsy in our study and other studies from Iran and other countries.