Clinicopathological features and medium-term outcomes of histologic variants of primary focal segmental glomerulosclerosis in adults: A retrospective study.

BACKGROUND: The Columbia classification identified five histological variants of focal segmental glomerulosclerosis (FSGS). The prognostic significance of these variants remains controversial. AIM: To evaluate the relative frequency, clinicopathologic characteristics, and medium-term outcomes of FSGS variants at a single center in Pakistan. METHODS: This retrospective study was conducted at the Department of Nephrology, Sindh Institute of Urology and Transplantation, Karachi, Pakistan on all consecutive adults (≥ 16 years) with biopsy-proven primary FSGS from January 1995 to December 2017. Studied subjects were treated with steroids as a first-line therapy. The response rates, doubling of serum creatinine, and kidney failure (KF) with replacement therapy were compared between histological variants using ANOVA or Kruskal Wallis, and Chi-square tests as appropriate. Data were analyzed by SPSS version 22.0. P-value ≤ 0.05 was considered significant. RESULTS: A total of 401 patients were diagnosed with primary FSGS during the study period. Among these, 352 (87.7%) had a designated histological variant. The not otherwise specified (NOS) variant was the commonest, being found in 185 (53.9%) patients, followed by the tip variant in 100 (29.1%) patients. Collapsing (COL), cellular (CEL), and perihilar (PHI) variants were seen in 58 (16.9%), 6 (1.5%), and 3 (0.7%) patients, respectively. CEL and PHI variants were excluded from further analysis due to small patient numbers. The mean follow-up period was 36.5 ± 29.2 months. Regarding response rates of variants, patients with TIP lesions achieved remission more frequently (59.5%) than patients with NOS (41.8%) and COL (24.52%) variants (P < 0.001). The hazard ratio of complete response among patients with the COL variant was 0.163 [95% confidence interval (CI): 0.039-0.67] as compared to patients with NOS. The TIP variant showed a hazard ratio of 2.5 (95%CI: 1.61-3.89) for complete remission compared to the NOS variant. Overall, progressive KF was observed more frequently in patients with the COL variant, 43.4% (P < 0.001). Among these, 24.53% of patients required kidney replacement therapy (P < 0.001). The hazard ratio of doubling of serum creatinine among patients with the COL variant was 14.57 (95%CI: 1.87-113.49) as compared to patients with the TIP variant. CONCLUSION: In conclusion, histological variants of FSGS are predictive of response to treatment with immunosuppressants and progressive KF in adults in our setup.

Clinical Course and Long-term Outcome of Adults with Primary Focal Segmental Glomerulosclerosis: A Retrospective Cohort Study.

INTRODUCTION: Focal segmental glomerulosclerosis (FSGS) is one of the common causes of end-stage kidney disease (ESKD) in adults with primary glomerular diseases. Information on clinical course and long-term renal outcome of primary FSGS in adults are scanty. We aimed to determine the clinical course and long-term outcome of primary FSGS in a large number of adult patients from a tertiary care kidney center in Pakistan. METHODS: A retrospective review of the clinical charts of all adults (≥ 16 years) with a biopsy proven diagnosis of FSGS presenting to Sindh Institute of Urology and Transplantation, Karachi, between January 1995 and December 2017 was carried out. Cases with secondary FSGS were excluded. Relevant data items were retrieved both at baseline and on last follow-up. RESULTS: Among 401 adults with primary FSGS, 144 (35.9%) were followed for a mean duration of 66.6 ± 27.4 months, out of which, 129 (89.5%) were treated with steroids and immunosuppressants. Response to steroids was obtained in 62 (48%) patients, while 67 (52%) showed no response. Among responders, 24/62 (38.7%) relapsed after a mean duration of 24.2 ± 23.2 weeks, who were re-treated with same dose of steroids alone or combined with cyclosporine and all achieved remission. The long-term outcomes were significantly different between steroid responsive and nonresponsive cohorts. None of the patients in steroid responsive group developed ESKD or died, while 7 (10.4%) patients in nonresponsive group developed ESKD and 2 (3%) died. CONCLUSION: Almost half of adults with primary FSGS achieved sustained remission with steroids and immunosuppressants and consequently exhibited excellent long-term outcome.  DOI: 10.52547/ijkd.6815.