The Challenge of Type 3c Diabetes: From Accurate Diagnosis to Effective Treatment.

Type 3c diabetes mellitus is a secondary form of diabetes associated with pancreatic disease, primarily chronic pancreatitis, which impairs insulin and glucagon secretion, resulting in inadequate glycemic control. Often misdiagnosed as other types of diabetes, such as type 1 or type 2 diabetes mellitus, type 3c diabetes mellitus is characterized by significant glucose variability, increased insulin requirements, and risk of hypoglycemia. This case report describes a 24-year-old man with a history of hereditary chronic pancreatitis resulting from a serine protease 1 () gene pathogenic variant, who presented with fasting hyperglycemia and elevated glycated hemoglobin requiring early insulin therapy. In the absence of symptoms of exocrine pancreatic insufficiency, specific diagnostic criteria confirmed the diagnosis of pancreatogenic diabetes, and the use of a glucose monitoring system proved essential for optimal management. Therefore, appropriate screening for diabetes in patients with hereditary chronic pancreatitis, combined with accurate diagnosis and close monitoring, can lead to the development of individualized strategies to prevent complications and improve glycemic control.