Original Article Pathology of idiopathic nephrotic syndrome in children: are the adolescents different from young children?

Background. There is no specific data on the pathological lesions underlying idiopathic nephrotic syndrome (INS) in adolescents in Pakistan. Moreover, it is not known whether the pathological lesions in adolescents differ significantly from young children with INS in our setup. Materials and methods. A retrospective analysis was car-ried out on all patients with INS with onset 18 years of age. They were split into two groups: patients with onset of INS 12 years (young children group) and patients with onset 13 through 18 years of age (adolescent group). Renal biopsies were evaluated by light microscopy, immu-noflourescence and electron microscopy. The histopatho-logical lesions on renal biopsies were analyzed and compared between the two groups. Results. The adolescents comprised 173 (32.1%) patients, and there were 365 young children (67.8%). The mean age of adolescents at the time of onset of INS was 15.12 6 1.5 years and there were 113 boys (65.3%) and 60 girls (34.6%). The mean age of young children was 7.266 3.24 years and there were 231 boys (63.2%) and 134 girls (36.7%). Focal segmental glomerulosclerosis was the most common histo-pathological lesion in adolescents (36.4%) followed by min-imal change disease (MCD) (28.9%). Adolescent-onset INS had a significantly higher frequency of membranous glomer-ulonephritis and membranoproliferative glomerulonephritis (MPGN) (P < 0.05) and significantly lower frequency of MCD (P < 0.05) than early childhood-onset INS. Conclusions. Our data indicate that the pathological le-sions in adolescent INS are different from younger children and resemble more closely those seen in adults. Our find-ings are concordant with the few previously published stud-ies on this subject