Abstract: SA-PO0905
Rituximab in Atezolizumab-Associated IgA Vasculitis: A Bridge Between Renal Protection and Cancer Treatment
Session Information
- Glomerular Case Reports: ANCA, IgA, IgG, and More
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Arriola Montenegro, Jose J, Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
- Riaza Ortiz, Cristina, Hospital Clinico San Carlos, Madrid, Community of Madrid, Spain
- Sethi, Sanjeev, Mayo Clinic Division of Experimental Pathology and Laboratory Medicine, Rochester, Minnesota, United States
- Herrmann, Sandra, Mayo Clinic Division of Nephrology and Hypertension, Rochester, Minnesota, United States
Introduction
Immune checkpoint inhibitors (ICIs) have significantly improved cancer outcomes but can lead to immune-related adverse events, including AKI in 3–5% of patients. While acute tubulointerstitial nephritis is the most common form, glomerular diseases such as IgA nephropathy with crescentic glomerulonephritis are increasingly recognized. We report a case of ICI-associated IgA vasculitis successfully managed with rituximab.
Case Description
A 75-year-old man with metastatic small-cell neuroendocrine carcinoma and stage 3 CKD (baseline creatinine 1.55 mg/dL) due to obstructive uropathy s/p nephrostomy began treatment with atezolizumab, carboplatin, and etoposide. His course was complicated by recurrent UTIs, requiring temporary discontinuation of atezolizumab.Following treatment with cefepime and levofloxacin, he developed a pruritic rash on his extremities; skin biopsy confirmed IgA vasculitis. After resolution, atezolizumab was resumed (cycle 7), but the rash recurred with high serum creatinine (2.7 mg/dL) and CRP (35.5 mg/L). High-dose prednisone (80 mg daily) led to symptom improvement. Pre-treatment labs revealed elevated TNF-α (22.8 pg/mL), sIL2R (2843 pg/mL), IL-18 (1267 pg/mL), and urine retinol binding protein to creatinine ratio (4110 mcg/g).Kidney biopsy showed IgA nephropathy with focal necrotizing and crescentic glomerulonephritis, along with acute tubular injury—consistent with renal involvement of IgA vasculitis.These changes were attributed to ICI therapy, though a paraneoplastic mechanism was considered less likely due to favorable tumor response on imaging.Atezolizumab was discontinued. Rituximab, combined with a prednisone taper, led to renal recovery.
Discussion
Atezolizumab,has been linked to a range of glomerular pathologies. Although rare, ICI-induced IgA vasculitis with crescentic features is an emerging entity. Rituximab may support renal function while preserving oncologic efficacy and reducing corticosteroid burden.