Changing trends of histopathology in childhood nephrotic syndrome in western Saudi Arabia

OBJECTIVE: It is widely accepted that minimal change nephrotic syndrome is the most common cause of nephrosis in children. Recent studies have demonstrated an increasing incidence of focal segmental glomerulosclerosis in adults and children. This study was conducted to analyze the trend of histopathologic subtypes in idiopathic nephrotic syndrome in the western area of the Kingdom of Saudi Arabia. METHODS: To determine the possible changes in the etiology of childhood nephrosis, the clinical charts of 46 pediatric patients diagnosed with idiopathic nephrotic syndrome between 1997 and 2001, group A, were reviewed. Results were compared with our initial published data of 132 patients with idiopathic nephrotic syndrome diagnosed between 1983 and 1992, group B. RESULTS: There was no difference in the percentage of biopsies between group A (43%) and group B (31.8%), P= 0.9. There was a decline in the incidence of minimal change nephrotic syndrome in recent years. Even if we assume that all patients without a histological diagnosis had minimal change nephrotic syndrome, presumptive minimal change nephrotic syndrome, the total incidence of minimal change nephrotic syndrome (biopsy proven + presumptive) in group A, was only 65% compared to 79.5% in group B, P=0.02. The incidence of focal segmental glomerulosclerosis was significantly greater in biopsies performed in the recent period, group A, 35% versus group B, 16.7%, P=0.05, and in the total number when we included the presumptive minimal change nephrotic syndrome, group A, 15.2% and group B, 5.3%, P<0.0001. Similarly we found an increased incidence of membranoprolifrative glomerulonephritis in total patients when we included the presumptive minimal change nephrotic syndrome, group A, 13.0% and group B, 5.3%, P=0.02. CONCLUSION: There is a shift toward an increasing prevalence of focal segmental glomerulosclerosis and membranoprolifrative glomerulonephritis over the years in the western area of the Kingdom of Saudi Arabia. These findings may have significant implications in the management of childhood nephrotic syndrome.