Diabetic ketoacidosis shortly after COVID‐19 vaccination in a non–small‐cell lung cancer patient receiving combination of PD‐1 and CTLA‐4 inhibitors: A case report.

We describe a case of diabetic ketoacidosis (DKA) shortly after the SARS‐CoV‐2 (COVID‐19) vaccination in a 65‐year‐old woman with non–small‐cell lung cancer under a combination treatment of programmed cell death protein 1 (PD‐1) and cytotoxic T‐lymphocyte‐associated protein 4 (CTLA‐4) inhibitors. She had no history of diabetic mellitus. A few days after the second shot of COVID‐19 vaccination, she developed DKA. We speculate that the immune‐related adverse event and immunogenicity of vaccination synergistically induced DKA. [ABSTRACT FROM AUTHOR]