Most cases of chronic pancreatitis are associated with drinking excessive amounts of alcohol over a long period of time.
However, in up to 3 out of 10 people with the condition, the cause can't be identified – known as "idiopathic" chronic pancreatitis.
Some of the known causes of chronic pancreatitis are outlined below.
Heavy drinking over many years can cause repeated episodes of acute pancreatitis. Acute pancreatitis is usually a short-term condition, but it can recur if you continue to drink alcohol.
Over time, repeated inflammation causes permanent damage to the pancreas, resulting in chronic pancreatitis.
Anyone who regularly consumes alcohol has an increased risk of chronic pancreatitis, although only a minority develop the condition.
Read more about alcohol misuse.
Problems with the immune system
Rare cases of chronic pancreatitis are the result of a problem with the immune system, which causes it to attack the pancreas. This is known as "autoimmune pancreatitis" and it's not clear exactly why it happens.
Many people with autoimmune pancreatitis also have other conditions caused by the immune system attacking healthy tissue. These include ulcerative colitis or Crohn’s disease, both of which cause inflammation inside the digestive system.
Some cases of chronic pancreatitis are inherited. This is thought to be caused by mutations (alterations) in a number of genes, including genes called PRSS1 and SPINK-1. These mutations disrupt the normal working of the pancreas.
Genetic mutations may also have a role in the effect of alcohol on your pancreas. Evidence suggests that certain genetic mutations make the pancreas more vulnerable to the harmful effects of alcohol.
Certain mutations of the CFTR gene, responsible for cystic fibrosis, are also thought to cause chronic pancreatitis in a small amount of cases.
Several other rare causes of chronic pancreatitis have also been identified, including:
- injury to the pancreas
- blocked or narrowed openings (ducts) of the pancreas
- radiotherapy to the abdomen (tummy)