Background: Immune checkpoint inhibitors (ICIs), including pembrolizumab, are increasingly used in cancer therapy, particularly for melanoma. While effective, these agents are associated with various ..
Background: Immune checkpoint inhibitors (ICIs), including pembrolizumab, are increasingly used in cancer therapy, particularly for melanoma. While effective, these agents are associated with various immune-related adverse events (IRAEs), including endocrine disorders like diabetic ketoacidosis (DKA). This report aims to contribute to the understanding of pembrolizumab-induced DKA, especially in patients with pre-existing prediabetes. Case Presentation: A 78-year-old male with a history of melanoma, prediabetes, and other comorbidities developed DKA after 1.5 years of pembrolizumab treatment. He presented with symptoms of weakness, thirst, dry mouth, and diarrhea, alongside severe hyperglycemia and metabolic acidosis. Diagnostic workup confirmed DKA, and his clinical improvement followed intensive management including intravenous fluids, insulin therapy, and electrolyte replacement. Endocrinology evaluation suggested pembrolizumab-induced insulin-dependent diabetes due to low C-peptide levels. Discussion: Pembrolizumab, a PD-1 inhibitor, may trigger DKA in patients through mechanisms potentially involving autoimmune destruction of pancreatic beta cells. This case underscores the need for awareness of this rare but serious side effect. Regular glucose monitoring and early intervention are crucial in managing patients on ICIs to prevent and address such complications. Conclusions: This case highlights the occurrence of DKA in a patient receiving pembrolizumab for melanoma, emphasizing the importance of monitoring glucose levels and prediabetes status in patients undergoing ICI therapy. Further research is needed to better understand the pathophysiology of pembrolizumab-induced diabetes and to develop preventive guidelines for this adverse effect.
