title: Histological heterogeneity of glomerular segmental lesions in focal segmental glomerulosclerosis.
abstract: Focal segmental glomerulosclerosis (FSGS) involves considerable histological heterogeneity in terms of location and quality of the glomerular segmental lesions. The present study investigated the heterogeneity of segmental lesions in each variant of FSGS, determined by the Columbia classification, and its clinical relevance. All glomerular segmental lesions of 80 cases of primary FSGS were evaluated histologically based on location [tip (TIP), perihilar (PH), or not otherwise specified (NOS)], and quality (cellular or fibrous). Among the 1,299 glomeruli of the 80 biopsy specimens, 210 glomeruli (16.2%) had segmental lesions, comprising 57 (27%) cellular TIP, 4 (2%) fibrous TIP, 42 (20%) cellular NOS, 86 (41%) fibrous NOS, and 21 (10%) fibrous PH lesions. Each case was also classified into one of the five histological variants of the Columbia classification: collapsing (COL), TIP, cellular (CEL), PH, or NOS. Overlap of segmental lesions in different location categories was seen in the COL, TIP, and PH variants, and heterogeneity of quality was apparent in the COL and CEL variants. Histological findings of the CEL variant (endocapillary hypercellularity) were observed in nine of the 13 COL variants. Both location and quality correlated with disease duration, degree of proteinuria, and histological severity of global glomerular sclerosis and tubulo-interstitial lesions. These results demonstrated the histological heterogeneity of glomerular segmental lesions in all variants of the Columbia classification, except NOS. However, the fidelity of location and dominance of histological features were generally conserved in the TIP and PH variants. The COL and CEL variants warrant further investigation because of their overlapping histological findings and apparent histological heterogeneity in the glomerular segmental lesions.
authors.affiliation: Department of Pathology, Tokyo Women's Medical University, 8-1 Kawada-cho, 162-8666 Shinjuku-ku, Tokyo, Japan.
authors.forename: Sekiko
authors.initials: S
authors.lastname: Taneda
authors.forename: Kazuho
authors.initials: K
authors.lastname: Honda
authors.forename: Keiko
authors.initials: K
authors.lastname: Uchida
authors.forename: Kosaku
authors.initials: K
authors.lastname: Nitta
authors.forename: Wako
authors.initials: W
authors.lastname: Yumura
authors.forename: Hideaki
authors.initials: H
authors.lastname: Oda
authors.forename: Michio
authors.initials: M
authors.lastname: Nagata
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D057911:Angiotensin Receptor Antagonists / Q000627:therapeutic use; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000627:therapeutic use; D001706:Biopsy; D003404:Creatinine / Q000097:blood; D018450:Disease Progression; D005923:Glomerulosclerosis, Focal Segmental / Q000145:classification* / Q000188:drug therapy / Q000473:pathology*; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D007676:Kidney Failure, Chronic / Q000473:pathology; D007678:Kidney Glomerulus / Q000473:pathology*; D008875:Middle Aged; D011507:Proteinuria / Q000209:etiology; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric; D013256:Steroids / Q000627:therapeutic use; D013997:Time Factors; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D057911:Angiotensin Receptor Antagonists; D000806:Angiotensin-Converting Enzyme Inhibitors; D007166:Immunosuppressive Agents; D013256:Steroids; D003404:Creatinine