A 36-year-old African American man presents to the Emergency Department with new onset body swelling. He has a history of HIV and is taking antiretrovirals and trimethoprim–sulfamethoxazole for prophylaxis. His last CD4 count was 125 cells/mm3 . His temperature is 38.2°C, blood pressure is 168/98 mmHg, heart rate is 94 beats per minute, and respiratory rate is 24 breaths per minute. Laboratory workup reveals a creatinine of 1.8 mg/dL, and a urine dipstick shows 4+ protein.
What is most likely to be seen on renal biopsy under light microscopy?
A. Normal appearing glomeruliCollapsed and sclerotic glomeruli surrounded by normal glomeruli. FSGS is one of the most common causes of nephrotic syndrome, and it is the most common cause in both black patients and in HIV patients. The diagnosis can be made with a renal biopsy that shows focal (only affecting some glomeruli) and segmental (only affecting part of a glomerulus) sclerosis. In HIV, the most common histologic variant is the collapsing form of FSGS. It is important to recognize that FSGS is a common cause of the nephrotic syndrome, especially in black patients and HIV patients. (A) Minimal change disease will show normal appearing glomeruli under light microscopy and epithelial foot process fusion under electron microscopy. (B) This pathologic finding is seen with membranous nephropathy. (C) This finding is seen in Alport syndrome, which is caused by a mutation in type IV collagen.