Pancreatitis is inflammation of the pancreas. It occurs when pancreatic enzymes (especially trypsin) that digest food are activated in the pancreas instead of the small intestine. It may be acute â€“ beginning suddenly and lasting a few days, or chronic â€“ occurring over many years. It has multiple causes and symptoms.
The most common symptoms of pancreatitis are severe upper abdominal pain radiating to the back, nausea, and vomiting that is worsened with eating. The physical exam will vary depending on severity and presence of internal bleeding. Blood pressure may be elevated by pain or decreased by dehydration or bleeding. Heart and respiratory rates are often elevated. The abdomen is usually tender but to a lesser degree than the pain itself. As is common in abdominal disease, bowel sounds may be reduced from reflex bowel paralysis. Fever or jaundice may be present. Chronic pancreatitis can lead to diabetes or pancreatic cancer. Unexplained weight loss may occur from a lack of pancreatic enzymes hindering digestion.
Eighty percent of pancreatitis is caused by alcohol and gallstones. Gallstones are the single most common etiology of acute pancreatitis. Alcohol is the single most common etiology of chronic pancreatitis.
Some medications are commonly associated with pancreatitis, most commonly corticosteroids such as prednisolone, but also including the HIV drugs didanosine and pentamidine, diuretics, the anticonvulsant valproic acid, the chemotherapeutic agents L-asparaginase and azathioprine, estrogen by way of increased blood triglycerides, cholesterol-lowering statins and the antihyperglycemic agent sitagliptin.
There is an inherited form that results in the activation of trypsinogen within the pancreas, leading to autodigestion. Involved genes may include Trypsin 1, which codes for trypsinogen, SPINK1, which codes for a trypsin inhibitor, or cystic fibrosis transmembrane conductance regulator.
Other common causes include trauma, mumps, autoimmune disease, scorpion stings, high blood calcium, high blood triglycerides, hypothermia, and endoscopic retrograde cholangiopancreatography (ERCP). Pancreas divisum is a common congenital malformation of the pancreas that may underlie some recurrent cases. Pregnancy can be a cause, possibly by increasing blood triglycerides. Diabetes mellitus type 2 is associated with a 2.8-fold higher risk.
Less common causes include pancreatic cancer, pancreatic duct stones, vasculitis (inflammation of the small blood vessels in the pancreas), coxsackievirus infection, and porphyria—particularly acute intermittent porphyria and erythropoietic protoporphyria.