Background: Idiopathic steroid resistant nephrotic syndrome (ISRNS) represents about 10-20% of children with nephrotic syndrome with variable outcome.
Objectives: To determine the histological patterns of ISRNS in Egyptian children and the histological details of the commonest types which might be the reason for the steroid resistance.
Patients and Methods: The study included 53 cases with ISRNS. Their renal biopsies were retrieved from the archive of Electron microscopy unit and pathology department, Ain Shams University Specialized Hospital (ASUSH) in the duration from 2005-2011. The biopsies were examined histologically, with immunohistochemistry, and by electron microscopy.
Results: They were 36 males (67.9%) and 17 females (32.1%), the age at diagnosis ranged from 1.5- 16 years with a mean of 6.71 years. Lower limb oedema was the commonest presentation (100%), haematuria was revealed in (17%) of cases. Histological examination showed three major patterns; Focal segmental glomerulosclerosis (FSGS) in 30.2%, minimal change glomerulopathy (MCG) in 24.5% and IgA nephropathy in 13.2 %.
Mesangial hypercellularity was very common among MCG patients (85.3% ±6.7). Tubulointerstitial inflammation and fibrosis were common among cases with IgA nephropathy (40.4% ±11, 53.7% ±8 respectively).
Conclusions: ISRNS in Egyptian children could be attributed mainly to three major diseases (FSGS, MCG and IgA nephropathy). Mesangial hypercellularity and severe tubulointerstitial disease might be the major causes for steroid resistance in MCG and IgA nephropathy respectively. Renal biopsy with electron microscopy examination should be done for all children with nephrotic syndrome at first time of presentation for proper assignment of treatment protocol.