A 34-year-old Hispanic man with HIV presented with gradual onset lower-extremity edema over the past 2 months. He was diagnosed with HIV 10 years earlier. It has been well controlled on bictegravir-emtricitabine-tenofovir. He does not take any other medications, including nonsteroidal anti-inflammatory drugs. His blood pressure was 131/80 mm Hg. There is 1+ edema in bilateral ankles. Otherwise, his physical examination was unremarkable.

Laboratory tests showed a serum creatinine level of 1.3 mg/dL (baseline 0.9 mg/dL). Urine dip stick was positive for blood and protein; urine protein was 6.8 g in 24-hour urine collection.

A renal biopsy was performed (Figure 1). The glomeruli exhibited diffuse mesangioproliferation, endocapillary proliferation with focal segmental glomerulosclerosis, and focal segmental cellular crescents (10%). The tubular interstitium was largely unchanged. On immunofluorescent microscopy, glomerular capillary walls segmentally and mesangial regions globally exhibited granular staining with IgG (1+), IgA (4+), IgM (trace), C1q (1+), and C3 (3+). Electron microscopy revealed prominent electron dense (immune complex) deposits predominantly in the mesangial regions. Multiple tubuloreticular structures in the endothelial cells were noted. Additionally, there was patchy podocyte effacement.

This case was prepared by Yongen Chang, MD, PhD, Assistant Clinical Professor, Division of Nephrology and Hypertension, University of California-Irvine, and Jonathan Zuckerman, MD, PhD, Assistant Clinical Professor, Department of Pathology, University of California-Los Angeles.

Figure 1. Renal biopsy images of this patient. (A) Light microscopy shows a glomerulus with mesangial hypercellularity, segmental endocapillary hypecellularity, and a cellular crescent.
Figure 1. Renal biopsy images of this patient. (B) Immunofluorescence microscopy shows dominant IgA staining in the mesangial and capillary region of the glomerulus.
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