Chronic pancreatitis is long-standing inflammation of the pancreas that results in irreversible deterioration of the structure and function of the pancreas.
In the United States, less than half of the cases of chronic pancreatitis are due to alcoholism. The remaining cases occur in people who have cystic fibrosis or carry the cystic fibrosis genes, hereditary pancreatitis, or autoimmune pancreatitis. Some cases of chronic pancreatitis have no clear cause (idiopathic). Rarely, an attack of severe acute pancreatitis makes the pancreatic duct so narrow that chronic pancreatitis results. In tropical countries (for example, India, Indonesia, and Nigeria), chronic pancreatitis of unknown cause occurs among children and young adults (called tropical pancreatitis).
Symptoms of chronic pancreatitis may be identical to those of acute pancreatitis (see Acute Pancreatitis) and generally fall into two patterns. In one pattern, a person has persistent upper abdominal pain that varies in intensity. In this pattern, a complication of chronic pancreatitis, such as an inflammatory mass, a cyst, or even pancreatic cancer, is more likely. In the second pattern, a person has intermittent flare-ups (bouts or attacks) of pancreatitis with symptoms similar to those of mild to moderate acute pancreatitis. The pain sometimes is severe and lasts for many hours or several days. With either pattern, as chronic pancreatitis progresses, cells that secrete the digestive enzymes are slowly destroyed (over about a 6- to 10-year period), so eventually the pain may stop.
As the number of digestive enzymes decreases (a condition called pancreatic insufficiency), food is inadequately broken down. Food that is inadequately broken down is not absorbed properly (malabsorption), and the person may produce bulky, unusually foul-smelling, greasy stools (steatorrhea). The stool is light-colored and may even contain oil droplets. Undigested muscle fibers may also be found in the feces. The inadequate absorption of food also leads to weight loss. Eventually, the insulin-secreting cells of the pancreas may be destroyed, gradually leading to diabetes.
A doctor suspects chronic pancreatitis because of a person's symptoms or history of acute pancreatitis flare-ups or alcohol abuse. Blood tests are less useful in diagnosing chronic pancreatitis than in diagnosing acute pancreatitis, but they may indicate elevated levels of amylase and lipase (two enzymes produced by the pancreas). Also, blood tests can be used to check the level of sugar (glucose) in the blood, which may be elevated.
Computed tomography (CT) may be done to show changes of chronic pancreatitis. If the CT scan does not show any abnormalities, doctors may do endoscopic retrograde cholangiopancreatography (ERCP—see Endoscopic Retrograde Cholangiopancreatography and Fig. 2: Understanding Endoscopic Retrograde Cholangiopancreatography), endoscopic ultrasonography (passage of a flexible viewing tube through the mouth into the stomach and the first segment of the small intestine), and tests of the function of the pancreas. Many doctors now do a special magnetic resonance imaging (MRI) test called magnetic resonance cholangiopancreatography (MRCP) instead of CT. MRCP shows the bile and pancreatic ducts more clearly than does CT.
People with chronic pancreatitis are at increased risk of pancreatic cancer. Worsening of symptoms, especially narrowing of the pancreatic duct, makes doctors suspect cancer. In such cases, a doctor is likely to do blood tests, an MRI scan, a CT scan, or an endoscopic study.
Treatment of repeated flare-ups of chronic pancreatitis is similar to that of acute pancreatitis (see Acute Pancreatitis). Even if alcohol is not the cause, all people with chronic pancreatitis should avoid drinking alcohol. Avoiding all food and receiving only fluids given by vein (intravenously) can rest the pancreas and intestine and may relieve a painful flare-up. In addition, opioid analgesics (see see Opioid Analgesics) are sometimes needed to relieve the pain. Too often, these measures do not relieve the pain, requiring increased amounts of opioids, which may put the person at risk of addiction. Medical treatment of chronic pancreatic pain is often unsatisfactory.
Later, eating four or five meals a day consisting of food low in fat may help reduce the frequency and intensity of the flare-ups. For people who no longer produce adequate digestive enzymes, taking tablets or capsules of pancreatic enzyme extracts with meals can make the stool less greasy and improve food absorption, but these problems are rarely eliminated. If necessary, a histamine-2 (H2) blocker or a proton pump inhibitor (drugs that reduce or prevent the production of stomach acid) may be taken with the pancreatic enzymes. With such treatment, the person usually gains some weight, has fewer daily bowel movements, has no more oil droplets in the stool, and generally feels better. If these measures are ineffective, the person can try decreasing fat intake. Supplements of the fat-soluble vitamins (A, D, E, and K) also may be needed.
If pain continues, a doctor searches for complications, such as an inflammatory mass in the head of the pancreas or a pseudocyst (a collection of pancreatic enzymes, fluid, and tissue debris resembling a cyst). An inflammatory mass may require surgical treatment. A pancreatic pseudocyst that causes pain as it expands may have to be drained (decompressed).
If the person has continuing pain and no complications, the doctor may recommend injecting a combination of the anesthetic bupivacaine and alcohol into the nerves from the pancreas to block pain impulses from reaching the brain. If this procedure does not work, which is frequently the case, surgical treatment may be an option if the pancreatic ducts are dilated or if there is an inflammatory mass in one region of the pancreas. For instance, when the pancreatic duct is dilated, creating a bypass from the pancreas to the small intestine relieves the pain in about 70 to 80% of people. When the duct is not dilated, part of the pancreas may have to be removed. Removing part of the pancreas means that cells that produce insulin are removed as well, and diabetes may develop. Doctors reserve surgical treatment for people who have stopped using alcohol and who can manage any diabetes that develops.
Hypoglycemic drugs taken by mouth rarely help treat diabetes caused by chronic pancreatitis. Insulin is generally needed but can cause a problem, because affected people also have decreased levels of glucagon, which is a hormone that acts to balance the effects of insulin. An excess of insulin in the bloodstream causes low sugar levels in the blood, which can result in a hypoglycemic coma (see see Symptoms).
Last full review/revision November 2012 by Steven D. Freedman, MD, PhD