الفهرس 
Anatomy of the PancreasOnly 14 pages are availabe for public view
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Abstract
Acute pancreatitis refers to inflammation of the pancreas, causing sudden and severe abdominal pain. The pancreas is an organ that lies in the back of the mid-abdomen. It produces digestive juices and certain hormones, including insulin. Pancreatitis usually develops as a result of gallstones or moderate to heavy alcohol consumption over a period of years. Most attacks of acute pancreatitis do not lead to complications, and most people recover uneventfully with medical care. However, a small proportion of people have a more serious illness that requires intensive medical care. In all cases, it is essential to determine the underlying cause of acute pancreatitis and, if possible, to treat this condition to prevent a recurrence.
Pancreatitis Causes:
There are many possible underlying causes of acute pancreatitis, but 60 to 75 percent of all cases are caused by gallstones or alcohol abuse.
Gallstone pancreatitis — Because the gallbladder and pancreas share a drainage duct, gallstones that lodge in this duct can prevent the normal flow of pancreatic enzymes and trigger acute pancreatitis.
Alcoholic pancreatitis — Alcohol is a common cause of acute pancreatitis. Alcoholic pancreatitis is more common in individuals who have a long history of alcohol abuse.
Drug-induced pancreatitis — A number of drugs used to treat medical conditions can trigger acute pancreatitis.
Post-ERCP — Endoscopic retrograde cholangiopancreato-raphy (ERCP) is a procedure that is done to evaluate the gallbladder or pancreas. Acute pancreatitis develops in about 3 to 5 percent of people who undergo ERCP. Most cases of ERCP-induced pancreatitis are mild.
Hereditary conditions — Acute pancreatitis can be caused by hereditary conditions, such as familial hypertriglyceridemia (high blood triglyceride levels) and hereditary pancreatitis. These conditions usually occur in children and young adults.
Unexplained — No underlying cause can be identified in about 20 percent of people with acute pancreatitis. This condition is called idiopathic pancreatitis. Only about 3 percent of this group will experience additional attacks over time.
Pathogenesis:
The exocrine pancreas produces a variety of enzymes, such as proteases, lipases, and saccharidases. These enzymes contribute to food digestion by breaking down food tissues. In acute pancreatitis, the worst offender among these enzymes may well be the protease trypsinogen which converts to the active trypsin. Trypsin is most responsible for auto-digestion of the pancreas which in turn causes the pain and complications of pancreatitis.
Symptoms and Signs:
The acute attack frequently begins following a large meal and consists of severe epigastric pain that radiates through to the back. The pain is unrelenting and usually associated with vomiting and retching. In severe cases, the patient may collapse from shock.Depending on the severity of the disease, there may be profound dehydration, tachycardia, and postural hypotension. Myocardial function is depressed in severe pancreatitis, presumably because of circulating factors that affect cardiac performance. Examination of the abdomen reveals decreased or absent bowel sounds and tenderness that may be generalized but more often is localized to the epigastrium. Temperature is usually normal or slightly elevated in uncomplicated pancreatitis. Clinical evidence of pleural effusion may be present, especially on the left. If an abdominal mass is found, it probably represents a swollen pancreas (phlegmon) or, later in the illness, a pseudocyst or abscess. In 1–2% of patients, bluish discoloration is present in the flank (Grey Turner sign) or periumbilical area (Cullen sign), indicating hemorrhagic pancreatitis with dissection of blood retroperitoneally into these areas.
Pancreatitis diagnosis:
Diagnosing acute pancreatitis can be difficult because the signs and symptoms of pancreatitis are similar to other medical conditions. The diagnosis is usually based upon a medical history, physical examination, and the results of diagnostic tests.
Laboratory Tests—Because pancreatic acinar cells synthesize, store, and secrete a large number of digestive enzymes (e.g., amylase, lipase, trypsinogen, and elastase), the levels of these enzymes are elevated in the serum of most pancreatitis patients. Because of the ease of measurement, serum amylase levels are measured most often.
Imaging tests — Imaging tests provide information about the structure of the pancreas, the ducts that drain the pancreas and gallbladder, and the tissues surrounding the pancreas. Imaging tests may include an x-ray of the abdomen, chest, CT scan or MRI of the abdomen.
Endoscopic retrograde cholangiopancreatography (ERCP) — Endoscopic retrograde cholangiopancreatography (ERCP) is a procedure that can be used to remove stones from the bile duct if your pancreatitis is due to gallstones or other problems with the bile or pancreatic ducts. In addition, ERCP can be used to treat some causes of pancreatitis.
Assessment of disease severity:
Accurate prediction of severity early in the course of disease offers potential benefits in that complications can be anticipated and detected early through the use of intensive monitoring and frequent clinical assessment, and early and aggressive therapies can be instituted to attempt to prevent these complications. Routine clinical assessment at the time of admission is associated with low sensitivities (<50%) in identifying patients with SAP. Therefore, alternative methods for assessing disease severity based on scoring systems, CT scanning, and serum markers have been widely studied. In addition to these methods, hemoconcentration and obesity have been reported to be predictive of severe disease.
Complications:
Complications can be systemic or locoregional:
• Systemic complications include ARDS, multiple organ dysfunction syndrome, DIC, hypocalcemia (from fat saponification), hyperglycemia and insulin dependent diabetes mellitus (from pancreatic insulin producing beta cell damage)
• Locoregional complications include pancreatic pseudocyst and phlegmon / abscess formation, splenic artery pseudoaneurysms, hemorrhage from erosions into splenic artery and vein, thrombosis of the splenic vein, superior mesenteric vein and portal veins (in descending order of frequency), duodenal obstruction, common bile duct obstruction, progression to chronic pancreatitis.
Pancreatitis treatment:
The goals of treatment of acute pancreatitis are to alleviate pancreatic inflammation and to correct the underlying cause. Treatment usually requires hospitalization for at least a few days.
Mild pancreatitis — Mild pancreatitis usually resolves with simple supportive care, which entails monitoring, drugs to control pain, and intravenous fluids. You may not be allowed to eat anything during the first few days, but most people can gradually resume eating within three to seven days.
Moderate to severe pancreatitis — Moderate to severe pancreatitis requires more extensive monitoring and supportive care. This is because severe pancreatitis can lead to potentially life-threatening complications, including damage of the heart, lung, and kidneys. People with pancreatitis of this severity may be closely monitored in an intensive care unit.
During this time you may be given one or more of the following treatments:
• Intravenous fluids are given to help prevent dehydration.
• Most people with moderate to severe pancreatitis will not be able to eat in the early course of their illness. Instead, you may be fed through a tube placed through the nose or mouth into the small intestine.If you cannot tolerate tube feeding or cannot get enough nutrients with tube feeding, you may be given nutrition through an intravenous line placed in the upper chest. You can resume eating gradually once your pain resolves and bowel function returns to normal.
• About 30 percent of people with severe acute pancreatitis develop an infection in the damaged pancreatic tissue. Antibiotics can prevent infections and control infections that are already present.
• Acute pancreatitis is sometimes complicated by extensive damage and/or infection to the pancreatic tissue. In these cases, the damaged and/or infected tissue may be removed in a procedure referred to as a necrosectomy. Necrosectomy can be done as a minimally invasive procedure.
Gallstone pancreatitis treatment — In people who have gallstone pancreatitis, the treatment of pancreatitis is usually coupled with the treatment of gallstones. This may include a procedure to relieve the blockage caused by the gallstone(s). Gallstone pancreatitis recurs in 30 to 50 percent of people after an initial attack of pancreatitis. Surgical removal of the gallbladder (cholecystectomy) is often recommended to prevent a recurrence. In people who are elderly and who have serious medical problems, it may not be safe to remove the gallbladder. In this case, ERCP can be done to enlarge the bile duct opening. This would allow stones from the gallbladder to pass, helping to prevent a recurrence of acute pancreatitis.
Prognosis:
The death rate associated with acute pancreatitis is about 10%, and nearly all deaths occur in a first attack and among patients with three or more Ranson criteria of severity. Respiratory insufficiency and hypocalcemia indicate a poor prognosis. The death rate associated with severe necrotizing pancreatitis is 50% or more, but surgical therapy lowers the figure to about 20%. Persistent fever or hyperamylasemia 3 weeks or longer after an attack of pancreatitis usually indicates the presence of a pancreatic abscess or pseudocyst.