Hypokalemic Paralysis Secondary to Immune CheckpointInhibitor Therapy

ntroduction of immune checkpoint inhibitors (ICIs) has led to signi1cant improvements in the treatment of multiple ma-lignancies. Anti-programmed cell death protein 1 (PD-1) and anti-cytotoxic T-lymphocyte antigen 4 (CTLA-4) are two essentialICIs that have been FDA approved since 2011. As the use of immunotherapy in melanoma and other malignancies increases, thepotential of adverse events also increases. Overall, anti-PD-1 agents are well tolerated. In rare instances, colitis, endocrinopathies,skin, and renal toxicities have been observed. A 58-year-old male with a history of stage 4 cutaneous melanoma presented withquadriplegia while on nivolumab. Routine blood test revealed low potassium, low bicarbonate, and high serum creatinine.Admission diagnosis included hypokalemia, acute kidney injury, and renal tubal acidosis. )e offending drug was discontinued,and the patient was started on high-dose corticosteroids. On discharge, paralysis was resolved. Renal function and potassium werenormalized. Nivolumab was discontinued, and he was started on pembrolizumab. Literature suggests that, although rare, patientsreceiving ICE may develop immune-mediated nephritis and renal dysfunction. )e mainstay of immune-related adverse event(irAE) management is immune suppression. Hence, given the increasingfrequency of immunotherapy use, awareness should beraised in regard to irAEs and their appropriate management.