Histopathological and Clinical Findings of Biopsy-Proven Focal and Segmental Glomerulosclerosis: A Retrospective Study

Abstract

BackgroundFocal segmental glomerulosclerosis (FSGS) is characterized by the presence of glomerular damage on histopathological examination. The major defining symptom of FSGS is proteinuria, which indicates damage to the glomerular filtration barrier. Additionally, FSGS is the most common cause of primary nephrotic syndrome. However, in Saudi Arabia, there is a paucity of research on this topic. Therefore, this study was designed to examine the clinical features, laboratory findings, and presence of comorbidities in patients with FSGS to determine their effects on clinical outcomes. MethodsWe retrospectively analyzed the histopathological and clinical data of patients diagnosed with FSGS via biopsy at King Abdulaziz University Hospital, Jeddah, Saudi Arabia, during the period 1989-2020. Biopsy samples were labeled according to the Columbia classification as tip, perihilar, cellular, collapsing, or not otherwise specified (NOS). ResultsWe included 39 children and 21 adults. Males accounted for 54.1% of the sample. Hypertension was the most common comorbidity. Regarding FSGS subtypes, 60.9% of the lesions in the adult patients were collapsing lesions, followed by NOS (26.1%). In pediatric patients, 36.8% of the lesions were NOS, followed by collapsing lesions (28.9%). We also observed a very low rate of remission. In both age groups, the most common clinical presentation was nephrotic syndrome. ConclusionWe found a high prevalence of collapsing and NOS FSGS subtypes in both the adult and pediatric age groups. The most prevalent outcome was the persistence of nephrotic syndrome with low rates of remission.

Current understanding of the molecular mechanisms of circulating permeability factor in focal segmental glomerulosclerosis

“…The established morphological classification, known as the Columbia Classification, distinguishes five different types of FSGS lesions based on their histologic presentation: collapsing, tip, cellular, perihilar, and not otherwise specified (NOS) ( 63 ). The FSGS NOS variant – defined by the exclusion of all other categories - is the most common among both the pediatric and adult populations ( 64 , 65 ). Interestingly, as previously discussed, lesions tend to change over time, with other variants evolving into a NOS phenotype, especially as the kidney approaches ESKD ( 12 , 66 ).…”