Acute Pancreatitis and Diabetes Mellitus—A Relation

Diabetes following acute pancreatitis (AP) is becoming increasingly recognized. It is unclear what subtype of diabetes mellitus (DM) occurs; however, type 3c diabetes mellitus (T3cDM) is gaining increasing recognition. Type 3c diabetes (also known as pancreatogenesis diabetes) is diabetes that comes secondary to pancreatic diseases, involving the exocrine and digestive functions of the pancreas. It also occurs following surgical removal of the pancreas. Around 5–10% of cases of diabetes in the Western world are related to pancreatic diseases. Chronic pancreatitis is most often the cause. Diabetes can also develop as a direct consequence of other diseases, including diseases of the exocrine pancreas. Historically, diabetes due to diseases of the exocrine pancreas was described as pancreatogenic or pancreatogenous diabetes mellitus, but recent literature refers to it as type 3c diabetes. It is important to note that type 3c diabetes is not a single entity; it occurs because of a variety of exocrine pancreatic diseases with varying mechanisms of hyperglycaemia. It has been observed that some patients have transient hyperglycaemia following AP episode with a subset developing persistent impaired glucose metabolism; however, the exact timeline is not well defined. The data on risk factors for developing DM after AP is limited and mixed; however, it is likely that severity of AP may impact the propensity to develop DM. The endocrine and exocrine pancreas are closely linked, and studies have found significant overlap in dysfunction of both after AP. Finally, there are some data to suggest that diabetes predisposes patients to structural changes in the pancreas and increased risk of developing AP.