The clinical significance of the glomerular location of segmental lesions in focal segmental glomerulosclerosis.

Serial sections of renal biopsies obtained from 44 nephrotic children with focal segmental glomerulosclerosis (FSGS) were reviewed in order to determine the glomerular location of segmental lesions and relate the findings to the outcome of illness. There were 23 boys and 21 girls aged 0.9-14.2 years at onset. FSGS was classified as "hilar" in biopsies containing at least one lesion contiguous with or involving the hilum, regardless of the location of other lesions, and as "peripheral" in the absence of hilar lesions. Of the 44 initial biopsies, 33 were designated hilar and 6 peripheral; the remaining 5 were unclassifiable as it was not possible to determine the location of 1-3 lesions in each biopsy. Twenty-eight of the 33 hilar biopsies also contained peripheral lesions, including paratubular (glomerular "tip") lesions in 15 instances. Paratubular lesions as the predominant abnormality were observed in only four biopsies. Repeat biopsies showed that transition occurred from one type to another, and only 4 biopsies remained with a final designation of peripheral FSGS. After a follow-up period of 1.6-24.9 years (mean 9.3), there was no significant difference in outcome between hilar and peripheral FSGS, whether diagnosed on the initial or repeat biopsy. The division into separate categories is not clearcut, and the use of this as a prognostic aid does not justify the additional cost of preparing and examining numerous serial sections.