Abstract: TH-PO0206
Beyond Cast Nephropathy: Lenalidomide-Induced Acute Interstitial Nephritis
Session Information
- Onconephrology: Anticancer Therapies, PTLD, Paraneoplastic Diseases, and More
November 06, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Onconephrology
- 1700 Onconephrology
Authors
- Selvam, Sri Abirami, Oregon Health & Science University, Portland, Oregon, United States
- Pradhan, Ajay B., Oregon Health & Science University, Portland, Oregon, United States
- Kung, Vanderlene Liu, Oregon Health & Science University, Portland, Oregon, United States
- Ellison, David H., Oregon Health & Science University, Portland, Oregon, United States
Introduction
Lenalidomide, a thalidomide analog, is widely used in multiple myeloma (MM) and other hematologic malignancies. Only five cases of lenalidomide-induced acute interstitial nephritis (AIN) have been reported. We present one such biopsy-proven case, making this a valuable addition to limited literature
Case Description
A 68-year-old woman with a history of CKD stage IIIb- baseline serum creatinine (sCr) ~1.1 mg/dL, hypertension, hypothyroidism, hyperlipidemia, anemia was diagnosed with kappa light chain MM following evaluation for a humeral fracture. She started combination therapy with daratumumab, bortezomib, lenalidomide (planned for 21 days), and dexamethasone (Dara-VRd). Seven days later, she was found to have a rising sCr (1.9 mg/dL) and non-pruritic rash. Lenalidomide was held for two days and resumed with antihistamines. On routine labs five days later, she was noted to have sCr 6.7 mg/dL, hyponatremia (124 mEq/L), and metabolic acidosis, requiring hospital admission. She was anuric and started on hemodialysis
Initial urinalysis was bland, showing few hyaline casts, no proteinuria or hematuria. Serum kappa light chains declined from 402 mg/L at start of chemotherapy to 207 mg/L when AKI occurred, suggesting improving disease burden, and arguing against myeloma cast nephropathy. Given the temporal association with lenalidomide exposure, drug-induced AIN was suspected. A kidney biopsy confirmed severe tubulointerstitial inflammation with prominent eosinophils, consistent with allergic AIN, and no evidence of myeloma cast nephropathy or any paraprotein-related disease. Prednisone was initiated at 60 mg daily, leading to rapid improvement in urine output, and discontinuation of dialysis within days. sCr a week after discharge was 1.9 mg/dL
Discussion
This case illustrates the importance of maintaining a broad differential when evaluating AKI in patients with MM. Emerging evidence suggests a spectrum of renal adverse effects associated with lenalidomide, including Fanconi syndrome, minimal change disease, and AIN—sometimes associated with DRESS syndrome. Specter et al. PMID: 20693160 reported that in patients receiving lenalidomide for AL amyloidosis, up to 32% developed severe renal dysfunction and 10% required dialysis. Early recognition, kidney biopsy, and timely initiation of corticosteroids were key to reversing kidney injury and avoiding prolonged dialysis dependence