Clinicopathological Outcomes in Focal Segmental Glomerulosclerosis: A Retrospective Cohort Study

Abstract

Introduction: Focal Segmental Glomerulosclerosis (FSGS) is a nephrotic syndrome with a variety of clinicopathological presentations and varied responses to treatment. Hence, this study attempts to classify FSGS based on clinical presentation and pathological findings on kidney biopsy, which is essential for appropriate treatment and avoidance of inappropriate use of immunosuppressants. Aim: To analyse clinicopathological findings and responses to immunosuppressants in FSGS. Materials and Methods: A retrospective cohort study was conducted at Department of Nephrology, Vydehi Institute of Medical Sciences and Research Centre Bengaluru, Karnataka, India, to analyse clinicopathological parameters such as urine analysis, 24-hour urine protein, serum creatinine, serum albumin, lipid profile, renal biopsy details, and response to treatment in 97 patients. The study was planned, analysed, and executed between January 2023 and February 2023. All variables were expressed as mean±standard deviation or percentage. Statistical analysis was performed using Statistical Package for Social Sciences (SPSS) software version 16.0. Results: Among a total of 97 patients, 64% were males. Sudden onset oedema was observed in 90% of the cases, while nephrotic proteinuria was seen in 71%. The Not Otherwise Specified (NOS) variant was noted in 60% of the cases. Complete remission was observed in 61%, suggesting a possible primary FSGS. Persistent nephrotic proteinuria with a poor response to therapy was noted in 32%, indicating a possible secondary/genetic FSGS, despite adequate immunosuppressive therapy. Therefore, differentiating between primary and secondary forms of FSGS has therapeutic and prognostic implications. Accurate diagnosis of each form of FSGS is vital to avoid unnecessary immunosuppressive-based therapy and establish appropriate treatment. Conclusion: Resistance to steroid therapy was observed in one-third of FSGS patients. It is likely that unrecognised genetic FSGS or secondary FSGS were included among the study group of primary FSGS, leading to misinterpretation of treatment responses in primary FSGS. Hence, a clinicopathological approach for correctly differentiating between primary FSGS, secondary (maladaptive, viral, or toxic) FSGS, and genetic FSGS helps in making correct treatment decisions.