Focal segmental glomerulosclerosis

(40%; CJASN 2017;12:502).

Primary:

permeability factor.

Secondary

• adaptive (hyperfiltration, sickle cell, obesity, anabolic steroids, OSA, ↑ protein, vesico-ureteral reflux);
• meds/toxins (IFN, bisphosphonates, NSAIDs, heroin), viral (COVID-19, HIV) or genetic (ApoL1 mutation in AA; JASN 2015;26:1443).