What is the pancreas?

Most of the food you eat would be as deadly as poison if it got directly into your bloodstream. Through the chemical wizardry of digestion your digestive tract disassembles virtually everything you eat into smaller components, ones that your body can use. One key element in that digestive process is the pancreas.

Most people have heard the word pancreas, but when asked, have no idea where this organ is located or what it really does. In fact, the pancreas is an elongated pear-shaped organ about 6 inches in length, somewhat wider on the right side and narrower on the left. Located deep within the body, it stretches across the upper abdomen, nestled behind the stomach and in front of the spine. To describe the pancreas, doctors divided it into three sections: the wider right end is called the head, the middle section the body and the narrow left end the tail

What does the pancreas do?

The pancreas is made up of two different types of tissue, each doing a different job - one helps digest the food and the other makes insulin to regulate blood sugar.

• Enzymes to digest food. First, the pancreas secretes powerful chemicals called digestive enzymes. Enzymes help break down large food molecules into smaller pieces that can be absorbed by the small intestine. (For example, a large protein molecule from a hamburger is broken down into small amino acid molecules.) To prevent the pancreas from digesting itself, these enzymes are stored in an inactivated form. When you eat, the pancreas releases these inactivated enzymes into a system of tiny drainage ducts that come together like branches of a tree and form the main pancreatic duct. Draining from left to right, the main pancreatic duct joins the common bile duct which drains bile from the liver and gallbladder. Together they empty their contents into the intestine through a small nipple in the wall of the duodenum called the papilla, or Ampulla of Vater. Once in the duodenum, the pancreatic enzymes are activated and begin breaking down and digesting your food.

   

• Insulin to control blood sugar. Secondly, the pancreas contains glandular, tissue which produces the hormone insulin. Insulin helps regulate blood sugar. When you eat, the starches and complex sugars in your food are broken down into simple sugar, glucose, and absorbed into your bloodstream. This raises the level of sugar in your blood. Acting like a thermostat, pancreas senses this rise in blood sugar. In response, it secretes insulin which carries sugar molecules out of the blood stream and into the cells of body where it is used for energy, or stored as fat.

It is a testament to reliability that most adults do not know much about the pancreas. We don't simply because we don't have to. From the moment of birth, the pancreas is like a machine on autopilot - silently working in the background doing its job meal after meal, day after day. We may only have one pancreas, but it usually lasts a lifetime processing over 100,000 meals and rarely ever breaks down. One problem that can occur, however, is acute pancreatitis, a sudden inflammation of the pancreas which causes severe upper abdominal pain.

What causes acute pancreatitis?

The most common cause of acute pancreatitis is gallstones, especially in female patients who are more prone to gallstone disease. As mentioned above, the pancreatic duct and bile duct share a common drain into the duodenum, called the papilla. Sometimes, a gallstone will sneak out of the gallbladder and travel down the bile duct. If the stone is too big to pass, it will often become lodged at the papilla. Sometimes, there is no actual stone, but a large amount of debris from the gallbladder called "sludge" which blocks the drain. In either case, this blockage causes a backup of pressure into the pancreatic ducts. This backup unintentionally activates the digestive enzymes within the pancreas itself. This is a big problem since the pancreas then begins to digest itself which releases even more enzymes, starting a chain reaction of self-destruction. This is acute pancreatitis.

The second most common cause of acute pancreatitis is chronic alcohol abuse, most often seen in men.

Other less common conditions that may cause acute pancreatitis include hereditary pancreatitis, blunt force abdominal trauma (like a steering wheel), post-ERCP pancreatitis, high blood calcium from overactive parathyroind gland or kidney failure, and high blood fat (triglyceride) levels. Certain medications may occasionally cause pancreatitis. These may include DDI (dideoxycytosine), DDC (dideoxyinosine), (Imuran) azathioprine, (Purinethol) 6-mercaptopurine, tetracycline, Depakene (valproic acid), Tylenol (acetaminophen), and others. Pancreatitis is associated with certain connective-tissue disorders such as Lupus (SLE), polyarteritis nodosa, and sarcoidosis. Infectious causes including viruses such as mumps, rubella, cytomegalovirus (CMV), HIV-AIDS, and others. Some bacteria can cause pancreatitis such as Campylobacter and Legionella. In approximately 15% of cases, the cause of acute pancreatitis is unknown, so-called idiopathic acute pancreatitis.

What are the symptoms?

Patient with acute pancreatitis generally complain of the sudden onset of severe pain in the upper mid-abdomen. The pain is a constant and may radiate to the back. Some patients have symptoms of nausea, vomiting and fever. Often, the pain is temporarily relieved by sitting up and bending forward - a characteristic of pancreatic pain.

How does your doctor know?

Diagnosis is the first step in treatment. If your doctor suspects that you may have acute pancreatitis, he will generally order several blood tests to confirm the diagnosis:

Blood tests

When pancreatitis is suspected, the first test performed is usually a blood test that measures the level of amylase and lipase. These are the normal enzymes that aid in the digestion of food in the intestine. They are made in the pancreas, secreted into the pancreatic ducts, and transported through the ducts to the intestine. When there is inflammation of the pancreas or blockage of the pancreatic ducts, lipase and amylase seep out of the pancreas and into the bloodstream.

• Amylase
  In cases of pancreatitis, the levels of amylase and lipase in the blood are usually higher than normal. How high the serum amylase levels depends on the severity of the disease. For example, the normal level of amylase is about 150. In mild cases of pancreatitis, it may be in the hundreds, and in severe cases, well over a thousand. On average, during uncomplicated cases, the serum amylase level starts increasing from two to 12 hours after the onset of symptoms and peaks at 12 to 72 hours. It usually returns to normal within one week. Rarely both amylase and lipase levels may be normal in a patient with CT-proved pancreatitis.

   

• Lipase
  An elevated lipase level is a bit more specific for pancreatitis since amylase is also produced in other organs of the body like the salivary glands. Lipase is only produced in the pancreas. Lipase levels increase within four to eight hours of the onset of clinical symptoms and peak at about 24 hours. Levels decrease within eight to 14 days. Likewise the normal blood level of lipase is 50. If the blood levels of amylase and lipase are elevated above the normal range, acute pancreatitis is likely. As the illness resolves, the blood levels fall, usually back to the normal range.

   

• Liver enzymes
  If pancreatitis is due to gallstone disease which also blocks the liver bile ducts, blood tests of liver function (SGOT, SGPT, bilirubin, alkaline phosphatase, GGTP) are often elevated as well.

• Ultrasound (Sonogram)
  Ultrasonography is often performed in the initial evaluation of suspected pancreatitis, especially when gallstones are suspected. Ultrasound is noninvasive, relatively inexpensive and may be performed at the bedside. The sensitivity of this study in detecting pancreatitis is good, but the pancreas is sometimes obscured secondary to bowel gas.

   

• Computed Tomography (CT scan)
  The contrast-enhanced CT scan provides the best imaging of the pancreas and surrounding structures. CT scanning is helpful in establishing the diagnosis and in assessing complications related to acute pancreatitis which may include enlargement of the pancreas, fat necrosis, abscess, or a pseudocyst.

   

• Endoscopic Retrograde Cholangiopancreatography (ERCP)
  ERCP has a limited role in management of acute pancreatitis since the test itself may inflame the pancreas worsening the condition. ERCP is sometimes used in patients with severe disease who are suspected of having an obstruction due to impacted gallstones. ERCP can be used to either remove the stones or temporarily bypass the obstruction with a plastic stent.. The risks of performing ERCP include precipitating an acute episode of pancreatitis, introducing infection and causing hemorrhage and perforation.

The treatment of pancreatitis may be conservative or aggressive depending upon the severity of inflammation and the development of complications. Since there is no currently proven medication for acute pancreatitis, treatment is mostly supportive. Most patients are hospitalized and given IV fluids. Since eating stimulates the pancreas, food is witheld for a few days to "rest" the pancreas.. Medications are given to control pain. The role of antibiotics is controversial. But, if infection is suspected, IV antibiotics are added. In prolonged cases, aggressive IV nutritional support is also necessary.

The risk of abdominal surgery is high in any seriously ill patient. Surgery is only performed as a last resort in acute pancreatitis. If there is suspicion of an uncontrolled abscess or severe necrosis (death) of pancreatic and surrounding tissue, a CT-guided fine-needle aspiration "tap" is often done. If dead tissue or active infection is found, surgery may be necessary to remove the dead tissue and drain the infection. If gallstones are found to be the cause of acute pancreatitis, it is best to have the gallbladder removed once the acute attack has resolved. Most patients are sent home and return to have the operation some time later. The operation to remove the gall bladder is called a cholecystectomy and, in most cases, can be done with minimally invasive laparoscopic "band-aid" surgery.

Complications

Acute pancreatitis is a serious disease. About 25% percent of patients with severe acute pancreatitis develop complications such as necrosis multiorgan failure (lungs, kidney, or heart), abscess, or pseudoscyst formation. Unfortunately, the serum amylase level and the lipase level are not specific enough measures of disease activity to predict these complications. Most complications of acute pancreatitis and deaths occur within two weeks of onset of pain.

• An abscess is an infected pocket of pus within the pancreas and is usually seen in the most severe cases. If antibiotics don't clear the infection up, the abscess may need to be drained surgically or by a needle that is guided by a CT scan x-ray.

   

• A pseudocyst ("pretend cyst") of the pancreas is a collection of fluid, blood, and dead tissue that is not infected like an abscess. Pseudocysts occur within a month after the acute episode in about in about one case in six. They sometimes disappear on their own, but can also require surgical or CT scan guided drainage.

Most patients (85%) recover fully from acute pancreatitis within a week or two and do not experience recurrence, if the cause is removed. Recurrences are common with continued alcohol abuse. However, in some cases, life-threatening complications develop such as necrosis, infection, liver, heart, or kidney impairment. The death rate is over high when these complications are present.

Chronic pancreatitis

Some patients do not recover fully and develop another complication of acute pancreatitis called chronic pancreatitis. The body has a great capacity to heal. But, sometimes acute pancreas is so severe that the pancreas is damaged beyond repair. This may occur after one severe attack of pancreatitis, but most often is seen after multiple acute episodes, often the result of continued alcohol abuse.

Symptoms of chronic pancreatitis include:

1. Persistent abdominal pain. This is especially seen after meals as the pancreas is stimulated by eating. The pain is due to ongoing inflammation, scar tissue, or cysts within the pancreas.

2. Weight loss. As the pancreas continues to fail, it produces less digestive enzymes. This makes it harder for your body to digest your food and undigested fat goes out with the bowel movements. This is due to malabsorption of food due to pancreatic failure with reduced production of digestive enzymes and insulin. Reduced enzyme production leads to impaired digestion and weight loss. Fat is not absorbed from the diet and escapes with the stool. Bowel movements become bulky, greasy, foul smelling and tend to float in the water because of their high fat content - a condition known as steatorrhea.

There are a few things that help. Prevention of acute pancreatitis is associated with prevention of the causative disorders. So, if you drink alcohol, control alcohol intake. If you have attacks of gallstone disease, consider elective surgery before you develop a case of "gallstone pancreatitis." Wear your seatbelt and use proper safety precautions to avoid abdominal trauma.

Summary

Acute pancreatitis is a variable ailment that may range from a mild to a life-threatening condition. Establishing an accurate diagnosis through laboratory testing and x-ray studies is important. Since there is no proven medical treatment, care is mostly supportive. Most cases of acute pancreatitis are mild the pancreas usually completely heals and the patient fully recovers. Patients with signs of severe disease should be hospitalized and closely monitored for signs of complications.