Beyond the Usual: A Rare Case of Lupus Podocytopathy and FSGS

Introduction: Lupus nephritis is a common manifestation of systemic lupus erythematosus. Lupus podocytopathy is a rare form of lupus nephritis (<1%) presenting with nephrotic syndrome and features of minimal change disease or FSGS. We report a challenging case of collapsing glomerulopathy in SLE, underscoring diagnostic and treatment complexities. Case Description: 30-year-old female with a history of cocaine use disorder, pulmonary embolism, and left hip avascular necrosis presented with joint pains, Raynaud’s phenomenon, and was diagnosed with SLE. She was prescribed hydroxychloroquine (HCQS) but was non-compliant. Four months later, she was admitted with chest pain and dyspnea. Labs showed creatinine 0.7 mg/dL, ANA 1:640 (homogeneous), anti-dsDNA 1157 IU/mL, spot UPCR 4 g/g, 24-hour protein 3.5 g, albumin 2.1 g/dL, leukopenia, normocytic anemia, thrombocytosis, and low C3. Echo revealed a posterior pericardial effusion, EF 30–35%, and severe LV hypertrophy. She was diagnosed with an SLE flare and started on prednisone and HCQS, and showed symptomatic improvement. The first renal biopsy was limited and showed focal segmental glomerulosclerosis (FSGS) consistent with lupus podocytopathy and mild lupus tubulointerstitial nephritis. A repeat renal biopsy confirmed collapsing glomerulopathy, lupus podocytopathy, minimal mesangial lupus glomerulonephritis (Class I), and lupus tubulointerstitial nephritis. IF revealed granular mesangial staining for IgA (1+), IgG (1+), IgM (1+), C1q (trace), C3 (1+), and kappa (1+). Both kappa and lambda light chains highlighted occasional mesangial immune deposits. Tubular cast staining was positive for IgA and kappa, while the tubular basement membrane showed positive staining for IgG and kappa. She received IV pulse steroids followed by prednisone, which were discontinued due to facial swelling. Mycophenolate was stopped due to pneumonia. She improved and was discharged on prednisone, with outpatient plans for tacrolimus. Discussion: Lupus podocytopathy is a rare lupus nephritis variant, often presenting as minimal change disease or FSGS, with collapsing forms being uncommon. It reflects immune-mediated podocyte injury. Though steroid-responsive, relapses are frequent, requiring additional immunosuppression. This case highlights treatment challenges due to medication intolerance. Emerging therapies like anifrolumab show promise.