Renal outcomes in myeloma associated acute kidney injury; a single centre experience

Introduction: At initial diagnosis of multiple myeloma (MM) 30% to 40% of patients has renal impairment and acute kidney injury (AKI) being most common renal presentation. Poor renal outcome is associated with poor overall survival of patients. Objectives: The present study was conducted to determine renal outcome in patients with newly diagnosed MM presenting with AKI. Patients and Methods: A prospective observational study was carried out from March 2016 to March 2021. We included newly diagnosed myeloma patients presenting with AKI. Diagnosis and staging of AKI was conducted by kidney disease improving global outcomes (KDIGO) guidelines. Diagnosis of MM was performed by International Myeloma Working Group (IMWG) criteria. Complete renal response was defined as estimated glomerular filtration rate (eGFR) of ≥60 mL/min. Statistical analysis was done using SPSS Statistics software version 28. Results: Total number of patients were 48 male, female was 32.16, median age was 69 years. With a median follow-up of 9 weeks 30 patients (62.5%) had complete renal response, 10 patients (20.8%) expired and 8 patients (16.6%) were dialysis dependent. On comparing patients with and without complete renal response, significant variables were serum creatinine (P<0.001), serum calcium (P<0.001), oliguria at presentation (P<0.001), RRT requirement (P<0.001), AKI stage Ⅲ (P<0.001) and light chain myeloma(P<0.001). On Kaplan Meier analysis oliguria at presentation (P<0.001), renal replacement therapy (RRT) requirement (P<0.001), AKI stage Ⅲ (P<0.001) and light chain myeloma (P<0.001) were significantly associated with poor renal outcomes. Conclusion: In patients with newly diagnosed MM presenting with AKI renal recovery is 62.5%. Factors associated with poor renal recovery are higher serum creatinine, oliguria, RRT requirement, AKI stage Ⅲ and light chain myeloma.