What is the difference between acute pancreatitis and chronic pancreatitis?
Acute pancreatitis is an isolated episode of abdominal pain accompanied by elevations in blood enzyme levels. Essentially, it describes active inflammation of the pancreas. More than 80 percent of the cases of acute pancreatitis are related to biliary stones or alcohol use. Acute pancreatitis may lead to chronic pancreatitis. Chronic pancreatitis is a painful disease of the pancreas in which inflammation has resolved, but with resultant damage to the gland characterized by fibrosis, calcification and ductal inflammation. It is possible for patients with chronic pancreatitis to have episodes of acute pancreatitis.
What causes chronic pancreatitis?
The most common cause of chronic pancreatitis in Western societies is alcohol. Alcohol consumption has been implicated in approximately 70 percent of cases as a major cause of this disease. Other causes include gallbladder disease, hyperparathyroidism (increased secretion from the parathyroid glands) and trauma to the pancreas. Tropical pancreatitis, a variant of chronic pancreatitis, is seen in tropical parts of Asia and Africa, and can affect children between 12 and 15 years of age. Its cause is unknown, although malnutrition is suspected to play a role.
Several major physiological factors contribute to the development of chronic pancreatitis in alcoholic patients. Alcohol may change the composition of proteins secreted by the pancreas, resulting in the formation of protein plugs within the small pancreatic ducts. It may also change the amounts of damaging proteases in pancreatic secretions. It is also thought that alcohol may have direct and indirect toxic effects, as well as systemic effects. Alcohol has been reported to have variable effects on the pressure at the sphincter of Oddi. Alcohol can precipitate and contribute to hyperlipidemia, a known risk factor for development of pancreatitis.
What are the symptoms of chronic pancreatitis?
Symptoms of chronic pancreatitis range widely from a sudden acute abdominal catastrophe to mild episodes of deep epigastric pain. Symptoms may include vomiting, constant dull, unremitting abdominal pain, epigastric tenderness, weight loss, steatorrhea and glucose intolerance. The pain of chronic pancreatitis often radiates to the back, although it may radiate to both upper and lower quadrants. Sitting up and leaning forward may relieve or reduce discomfort.
Diarrhea may be chronic (six or more bowel movements per day). The diarrhea is a result of fat malabsorption, which results in bulky, foul-smelling stools that may appear oily and float (steatorrhea).
How is chronic pancreatitis diagnosed?
Chronic pancreatitis is best diagnosed using historical information, serum enzymes, exocrine function and radiographic studies (X-rays). Tests of exocrine function (fat absorption) are helpful.
Are there any particular complications that result from chronic pancreatitis?
Yes. Nutrient malabsorption, diabetes mellitus and splenic vein thrombosis are common complications of chronic pancreatitis.
Malabsorption is faulty absorption of nutrients from the digestive tract. In chronic pancreatitis, malabsorption occurs after the capacity for enzyme secretion is reduced by more than 90 percent. In combination with a reduction in pancreatic enzyme secretion, a reduction in bicarbonate secretion lowers the pH in the duodenum. An abnormally low pH in the duodenum retards the digestion of fats.
Diabetes mellitus is a disorder of carbohydrate metabolism characterized by inadequate secretion or utilization of insulin, resulting in elevated blood glucose levels. Chronic pancreatitis affects the endocrine function of the pancreas, responsible for insulin and glucagon production.
Diabetes is common in patients with chronic pancreatitis, and the incidence increases over time with the progression of the disease. Approximately 45 percent of patients with chronic pancreatitis will develop diabetes. Fortunately, the pancreatic form of diabetes is usually mild and the usual complications (retinopathy, nephropathy and vasculopathy) are uncommon. Neuropathic complications may occur with continued alcohol abuse or malnutrition.
How is chronic pancreatitis treated?
Treatment for chronic pancreatitis includes medical, endoscopic and surgical therapy.
Pancreatic enzyme replacement is therapy that replaces enzymes, the production of which is reduced because of the disease process of pancreatitis. The goal of pancreatic enzyme replacement therapy is to control diarrhea and help the patient stabilize his/her body weight. These enzymes are critical to manage malabsorption. They are useful in significantly improving steatorrhea (passage of fat through the stool). In addition, pancreatic enzyme replacement therapy inhibits pancreatic secretions and may also decrease the pressure in the ductal system (decreasing pain).
A stent, or endoprosthesis, is a hollow synthetic tube that may be inserted in a pancreatic or biliary duct or sphincter to facilitate flow of pancreatic juice or bile.
Endoscopic sphincterotomy refers to the division of a muscle during endoscopy. This may be used to treat disorders of the muscle or to facilitate endoscopic therapy in the biliary and pancreatic ducts.
Surgery for chronic pancreatitis is indicated when more conservative approaches, such as medical and endoscopic, fail to give relief from symptoms.
In severe refractory cases, total removal of the pancreas (total pancreatectomy) with replacement of the insulin-producing islet cells is now a viable option.
Can patients expect long-term relief of pain after surgery?
Surgical intervention provides long-term relief of pain in 70 percent of patients. When patients have exhausted other avenues of treatment for pain relief, surgery should be considered.
If I have chronic pancreatitis and am being treated, can I expect a full recovery from this disease?
The changes of chronic pancreatitis are not reversible. However, it is possible to have control of pain and steatorrhea with medical, endoscopic, percutaneous or surgical treatment.