Renal Tubular Acidosis an Adverse Effect of PD-1Inhibitor Immunotherapy

Immune checkpoint blockade therapy is gaining popularity among oncologists for treatment of solid and hematologic ma-lignancies. )e widespread use of these agents resulted in increasing incidence of renal immune-related adverse events. Reportedrenal toxicity described so far includes acute interstitial nephritis, minimal change disease, and immune complex glomerulo-nephritis.Wereportthecaseofa79-year-oldfemalewithmetastaticnon-smallcelllungcanceronanti-PD-1therapynivolumab.Afterthe4thadministrationofnivolumab,thetreatmentcoursewascomplicatedwithnormalaniongapmetabolicacidosis.Urineand blood studies were in favor of distal renal tubular acidosis (RTA). Following a negative workup for an underlying etiology,immunotherapy-induced RTA was suspected. Withholding of the offending agent and initiation of steroid therapy resulted inadequate response. )e present report provides the first presentation of RTA as a renal immune-related adverse event secondaryto nivolumab. Nephrologists and oncologists should be familiar with potentially life-threatening renal side effects induced byimmune checkpoint inhibitors.