Case report on renal failure reversal in lambda chain multiple myeloma with bortezomib and dexamethasone.

Renal failure (RF) reversal in multiple myeloma (MM) is associated with an improved prognosis. Light chain myeloma, serum creatinine (SCr) > 4 mg/dL, extensive proteinuria, early infections, and certain renal biopsy findings are associated with lower rates of RF reversal. Our patient is a 67-year-old female with multiple poor prognostic factors for RF reversal who demonstrated a rapid renal response with bortezomib and dexamethasone (BD) regimen. She presented initially with altered mental status. On exam, she appeared lethargic and dehydrated and had generalized tenderness. She had been taking ibuprofen as needed for pain for a few weeks. Labs showed a white cell count-18,900/μL with no bandemia, hemoglobin 10.8 gm/dL, potassium-6.7 mEq/L, bicarbonate-15 mEq/L, blood urea nitrogen-62 mg/dL, SCr-5.6 mg/dL (baseline: 1.10), and corrected calcium-11.8 mg/dL. A rapid flu test was positive. Imaging studies were unremarkable. Her EKG showed sinus tachycardia and her urinalysis was unremarkable. The unexplained RF in an elderly individual in conjunction with hypercalcemia and anemia prompted a MM work-up; eventually, lambda variant MM was diagnosed. An immediate (4 days) renal response defined as 50% reduction in SCr was noticed after initiation of the BD regimen.