RT Book, Section A1 Dirkx, Tonja C. A1 Woodell, Tyler B. A2 Papadakis, Maxine A. A2 McPhee, Stephen J. A2 Rabow, Michael W. A2 McQuaid, Kenneth R. SR Print(0) ID 1193127509 T1 Focal Segmental Glomerulosclerosis T2 Current Medical Diagnosis & Treatment 2023 YR 2023 FD 2023 PB McGraw-Hill Education PP New York, NY SN 9781264687343 LK accessmedicine.mhmedical.com/content.aspx?aid=1193127509 RD 2024/04/23 AB This relatively common renal pattern of injury results from damage to podocytes; such damage may be a primary/renal-limited disorder or may be secondary to another underlying disease state. Primary causes fall into three categories: (1) heritable abnormalities in any one of several podocyte proteins, or underlying type 4 collagen mutations; (2) polymorphisms in the APOL1 gene in those of sub-Saharan African ancestry; or (3) increased levels of a circulating permeability factor. Secondary causes include renal overwork injury, obesity, hypertension, chronic urinary reflux, HIV or SARS-CoV-2 infection, or analgesic or bisphosphonate exposure. Genetic testing in primary cases is becoming more common, especially in the pediatric population.