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Pancreatitis is inflammation of the pancreas. This condition usually begins at an acute stage, and in some cases, may become chronic after a severe and/or recurrent attack. When the pancreas becomes inflamed, the digestive enzymes attack the tissue that produces them. One of these enzymes, called trypsin, can cause tissue damage and bleeding, and can cause the pancreas blood cells and blood vessels to swell. With chronic pancreatitis, the pancreas may eventually stop producing the enzymes that are necessary for your body to digest and absorb nutrients. This is called exocrine failure and fat and protein are not digested or absorbed. When chronic pancreatitis is advanced, the pancreas can also lose its ability to make insulin; this is called endocrine failure.
The pancreas is a large and important gland behind the stomach close to the duodenum. It digests your food and produces insulin, the main chemical for balancing the sugar level in the blood.
The pancreas is a solid gland about 10 inches (25cm) long. It is attached to the back of the abdominal cavity behind the stomach and is shaped like a tadpole. Its head is just to the right of the mid-line and its body and tail point upwards at an angle so that the tail is situated just beneath the extreme edge of the left side of the ribs. The head is closely attached to the first part of the small intestine (duodenum), into which the stomach empties food and liquid, already partially digested. It is to this partially digested food that the pancreas adds its digestive juices (enzymes).
The tube draining the liver of its bile (the bile duct) lies just behind the head of the pancreas and usually joins the bowel at the same place where the fluids from the pancreas enter the bowel. Running behind the body of the pancreas are many important blood vessels. Because of its position in the body, it is not easy for a surgeon to operate on the pancreas.
Food consists of carbohydrates (e.g. starch), proteins (e.g. meat), and fat (e.g. butter), and digestion is not possible without the enzymes produced by the pancreas.
The pancreas makes a number of different enzymes each of which is responsible for breaking down the different types of food into small particles suitable for absorption. The enzymes are made in small glands within the pancreas and travel along increasingly large tubes until finally they reach the main pancreatic tube. This connects the gland to the first part of the bowel where food passes after it has gone through the stomach.
The enzymes are not active when they are first made within the pancreas (otherwise they would digest the pancreas as well) but when they pass into the bowel they are activated by the juices in the bowel. The main enzymes are called amylase (which digests carbohydrates), trypsin (which digests protein) and lipase (which digests fats). The bile, which comes from the liver, is also very important for the digestion of fat because it acts like a soap and breaks up the fat into minute droplets so that the pancreatic lipase can digest it.
Insulin and Glucose
All the bodys cells use glucose (sugar) as an energy source. The level of sugar in the blood is kept constant by insulin, which is made by special cells in the pancreas. If the cells are not working properly and insulin is lacking then diabetes develops.
Depending upon how badly the pancreas functions there are two problems. The first is that food is poorly absorbed, which causes weight loss, and there is diarrhea, often rather fatty as the undigested fat causes pale, bulky and smelly motions. The second is, if too little insulin is made, diabetes develops with frequent passage of urine and weight loss. These two problems need not occur together.
The symptoms begin as those of acute pancreatitis:
Most chronic pancreatitis is due to alcohol abuse and is already chronic at its first presentation. In rare cases this condition leads to cancer of the pancreas, an unchecked growth of abnormal cells in the pancreas.
Your doctor will focus treatment on your nutritional and metabolic needs and on relieving your pain. Mild pain can be treatment with analgesics. If the cause of acute pancreatitis is gallstones, you may have to have your gallbladder removed to prevent further attacks. If the bile duct is found to be enlarged, you may need an ERCP (endoscopic retrograde cholangiopancreatography) to drain it. An ERCP is a way your doctor can examine your pancreas, pancreatic duct, the common bile duct, and/or sphincter of Oddi. It involves passage of a long narrow tube called an endoscope used to put X-ray contrast dye into the bile and pancreas ducts. In severe cases, surgery will be required to drain the pancreatic duct or to remove part of the pancreas.
Your doctor will also likely give you dietary guidelines to follow in order to reduce the amount of fat you eat, since your body has trouble digesting these substances. You may also need to take pancreatic enzyme supplements, which are in the form of a tablet, every time you have a meal. These supplements will help your body absorb food and help you regain some of the lost weight.
There are a very few research hospitals performing pancreas transplants. However, they are limited to kidney and pancreas transplants. It is possible to transplant the islet cells to the liver. The risk of complications is high, and the majority of these procedures have been placed on hold.
Are herbs and vitamins important?
Many physicians and practitioners are prescribing herbal and vitamin therapy. Many patients report fewer side effects, as well, as improved benefit. Ginger is well known for preventing nausea. Others formulations which promote healthy pancreatic function include Selenium, Chromium Picolate, and Milk Thistle.
Acute pancreatitis: This condition can occur suddenly, soon after the pancreas becomes damaged or irritated by its own enzymes. Although acute pancreatitis is not fully understood, its causes are usually gallstones or alcohol abuse. When gallstones pass through the bile duct, they may become stuck, causing enzymes to build up in the pancreas because they cannot drain through the duct, and damaging the pancreas. In the case of alcohol, the pancreas may be sensitive to the effects of excessive alcohol. The amount of alcohol consumed will vary from person to person. Other less common causes of this condition are: excessive levels of fat particles in the blood, mumps, drugs, surgery, heredity, and idiopathic (unknown cause). Acute pancreatitis affects about 80,000 Americans every year.
Chronic Pancreatitis: This stage of pancreatitis begins as acute pancreatitis, and becomes chronic when the pancreas becomes scarred. This condition is usually due to years of excessive alcohol consumption, but may also develop from other causes of pancreatitis.
Most cases of acute pancreatitis are mild and involve a short hospital stay to help heal the pancreas. Chronic pancreatitis is a much more persistent condition, and occurs more often in men than women.
Etiology and Pathogenesis
Biliary tract disease and alcoholism account for >= 80% of hospital admissions for acute pancreatitis. The remaining 20% are attributed to drugs (eg, azathioprine, sulfasalazine, furosemide, valproic acid), estrogen use associated with hyperlipidemia, infection (eg, mumps), hypertriglyceridemia, endoscopic retrograde pancreatography, structural abnormalities of the pancreatic duct (eg, stricture, cancer, pancreas divisum), structural abnormalities of the common bile duct and ampullary region (eg, choledochal cyst, sphincter of Oddi stenosis), surgery (particularly of stomach and biliary tract and after coronary artery bypass grafting), vascular disease (especially severe hypotension), blunt and penetrating trauma, hyperparathyroidism and hypercalcemia, renal transplantation, hereditary pancreatitis, or uncertain causes.
In pancreatitis, pancreatic enzymes activate complement and the inflammatory cascade, thus producing cytokines. Patients typically present with fever and an elevated WBC count. It may thus be difficult to determine if infection is the cause or has developed during the course of pancreatitis.
Most patients suffer severe abdominal pain, which radiates straight through to the back in about 50%; rarely, pain is first felt in the lower abdomen. Pain usually develops suddenly in gallstone pancreatitis versus over a few weeks in alcoholic pancreatitis. Pain is severe, often requiring large doses of parenteral narcotics. The pain is steady and boring and persists without relief for many hours and usually for several days. Sitting up and leaning forward may reduce pain, but coughing, vigorous movement, and deep breathing may accentuate it. Most patients experience nausea and vomiting, at times to the point of dry heaves.
The patient appears acutely ill and is sweating. Pulse rate is usually 100 to 140 beats/min. Respirations are shallow and rapid. BP may be transiently high or low, with significant postural hypotension. Temperature may be normal or even subnormal at first but may increase to 37.7 to 38.3° C (100 to 101° F) within a few hours. Sensorium may be blunted to the point of semicoma. Scleral icterus is occasionally present. Examination of the lungs may reveal limited diaphragmatic excursion and evidence of atelectasis.
About 20% of patients experience upper abdominal distention caused by gastric distention or a large pancreatic inflammatory mass displacing the stomach anteriorly. Pancreatic duct disruption may cause ascites (pancreatic ascites). Abdominal tenderness always occurs and is often severe in the upper abdomen and less severe in the lower abdomen. Mild-to-moderate muscular rigidity may exist in the upper abdomen but is rare in the lower abdomen.
Acute pancreatitis should be considered in the differential diagnosis of every acute abdomen. The differential diagnosis of acute pancreatitis includes a perforated gastric or duodenal ulcer, mesenteric infarction, strangulating intestinal obstruction, ectopic pregnancy, dissecting aneurysm, biliary colic, appendicitis, diverticulitis, inferior wall MI, and hematoma of abdominal muscles or spleen.
Laboratory tests cannot confirm a diagnosis of acute pancreatitis but can support the clinical impression. Serum amylase and lipase concentrations increase on the first day of acute pancreatitis and return to normal in 3 to 7 days. Both may remain normal if destruction of acinar tissue during previous episodes precludes release of sufficient amounts of enzymes to raise serum levels.
The need to treat severe acute pancreatitis in an ICU can frequently be determined on hospital day 1 by any of the following danger signals: hypotension, oliguria, hypoxemia, or hemoconcentration (ie, Hct > 50%, indicating severe third space losses).
Fluid resuscitation is essential; 6 to 8 L/day of replacement fluid containing appropriate electrolytes and colloid may be required.
Severe pain should be treated with meperidine 50 to 100 mg IM q 3 to 4 h prn in patients with normal renal function (morphine causes the sphincter of Oddi to contract and should be avoided). A serum glucose level of 200 to 250 mg/dL (11.1 to 13.9 mmol/L) should not be treated, but higher levels should be treated cautiously with subcutaneous or IV insulin and carefully monitored.
Heart failure should be treated by appropriate correction of volume status. Renal failure should be treated by increased fluid replacement if there is prerenal azotemia. Dialysis (usually peritoneal) may also be required.
Antibiotic use had been controversial. However, there is now evidence that antibiotic prophylaxis with imipenem can prevent infection of sterile pancreatic necrosis, although mortality is unaltered. Antibiotics should be used to treat specific infections (eg, biliary sepsis, pulmonary infection, UTI). If pancreatic infection is suspected, CT-guided needle aspiration should be performed.
In the USA, chronic pancreatitis most commonly results from alcoholism and idiopathic causes. Similar to acute pancreatitis, microlithiasis has been implicated in some cases of chronic pancreatitis. Rare causes are hereditary pancreatitis, hyperparathyroidism, and obstruction of the main pancreatic duct caused by stenosis, stones, or cancer. Rarely, severe acute pancreatitis causes sufficient pancreatic ductal stenosis to impair drainage and result in chronic pancreatitis.
Symptoms and signs may be identical to those of acute pancreatitis. Although there is occasionally no pain, severe epigastric pain may last many hours or several days. Possible causes include acute inflammation not recognized by conventional tests, distention of pancreatic ducts caused by strictures or calculi, a pseudocyst, perineural inflammation, or obstruction of either the duodenum or the common bile duct caused by fibrosis of the head of the pancreas. Abdominal pain may subside as acinar cells that secrete pancreatic digestive enzymes are progressively destroyed.
Laboratory tests, including amylase and lipase, are frequently normal, probably because of significant loss of pancreatic function. Markers of inflammation (eg, WBC count) are generally minimally elevated as well.
Structural abnormalities can be visualized by plain x-ray of the abdomen (showing pancreatic calcification, which indicates intraductal stones), abdominal ultrasound or CT (showing abnormalities in size and consistency of the pancreas, pancreatic pseudocyst, or dilated pancreatic ducts), and ERCP (showing abnormalities of the main pancreatic duct and secondary branches). However, these imaging studies may be normal in the first few years of disease.
The most sensitive test of pancreatic exocrine function is the secretin test. It involves positioning a tube in the duodenum and collecting pancreatic secretions stimulated by IV secretin alone or with either cholecystokinin or cerulein. Duodenal contents are collected for volume determination, HCO3 concentration, and enzyme concentration. A collection that is of normal volume (> 2 mL/kg) and low in HCO3 (< 80 mEq/L) suggests chronic pancreatitis; low volume (< 2 mL/kg), normal HCO3 (> 80 mEq/L), and normal enzyme levels suggest pancreatic duct obstruction, perhaps secondary to tumor, and should prompt ERCP.
A relapse of chronic pancreatitis may require treatment similar to that of acute pancreatitis. The patient must eschew alcohol. At times, IV fluids and fasting prove beneficial. Dietary measures of uncertain benefit include small feedings restricted in fat and protein (to reduce secretion of pancreatic enzymes) and an H2 blocker or antacids (to reduce acid-stimulated release of secretin, increasing the flow of pancreatic juice). Too often, these measures do not relieve pain, requiring increased amounts of narcotics, with the threat of addiction. Medical treatment of chronic pancreatic pain is often unsatisfactory.
Acute Pancreatitis The initial stage of pancreatitis, characterized by gradual or sudden severe pain in the center part of the abdomen that moves around to the back, signaling a damaged or irritated pancreas.
Bile A secretion of the liver that helps digest fats in the intestines.
Biliary system The ducts and tubes that collect and drain bile.
Chronic Pancreatitis Occurs when the symptoms of acute pancreatitis continue to recur. Usually due to years of excessive alcohol consumption, this condition may also develop from other cases of pancreatitis.
ERCP (Endoscopic Retrograde Cholangiopancreatography) A long, narrow tube called an endoscope used to examine the pancreas, pancreatic duct, common bile duct, and/or sphincter of Oddi. The scope can be used to put contrast dye into the pancreas to highlight stones or blockages, and can be used to remove blockages.
Diabetes mellitus A condition where the pancreas does not produce enough insulin to use carbohydrates.
Endocrine An internal gland secretion directly into the blood stream.
Exocrine The external secretion of a gland through a duct into the intestine.
Inflammation A response to tissue injury that causes redness, swelling, and sometimes pain.
Jaundice The skin and/or white of the eyes turns yellow. Itching may or may not occur.
Pancreas A gland that sits behind the stomach, and produces insulin to metabolize sugar and secretes enzymes to breakdown fats, proteins, and carbohydrates.
Pancreatic duct Drains pancreatic enzymes into the small intestine.
Sphincter of Oddi A circular, contracting muscle at the intestinal opening of the bile and pancreatic ducts.
CopyrightÓ ChiRhoClin 2002