The increasing incidence of initial steroid resistance in childhood nephrotic syndrome

Recently, a number of reports have highlighted changes in the histopathology and response to corticosteroid treatment in childhood nephrotic syndrome; however, these involved ethnically mixed populations. For comparison, the purpose of our research was to search for changes in the characteristics of nephrotic syndrome in a homogeneous population of Caucasian children over two consecutive decades.

Chart analysis was performed to identify children with new-onset nephrotic syndrome. The children were admitted to the Division of Pediatric Nephrology, Zabrze, during two periods: 1986-1995 (76 patients) and 1996-2005 (102 patients). Specifically, a comparison of clinical characteristics and morphology of nephrotic syndrome between the two groups was performed. Steroid resistance was defined as no remission within 8 weeks of corticosteroid treatment. Histopathology was available in 36.8% and 43.1% of patients respectively.

There was a significant increase in primary steroid resistance in the latter decade: 15.8% vs 31.4% (P = 0.017). Changes in the histopathology did not reach the level of statistical significance: minimal change nephrotic syndrome 25% vs 9% (P = 0.095), mesangial proliferative glomerulonephritis 46.4% vs 61.3% (P = 0.21), focal segmental glomerulosclerosis 17.9% vs 20.4% (P = 0.78), membranoproliferative glomerulonephritis 7.1% vs 6.8% (P = 1.0), membranous glomerulonephritis 3.6% vs 0% (P = 0.39).

Our results show the increasing incidence of primary steroid resistance in childhood nephrotic syndrome.