Abdominal Pain

Abdominal pain is felt in the abdomen. The abdomen is an anatomical area bounded by the lower margin of the ribs and diaphragm above, the pelvic bone (pubic ramus) below, and the flanks on each side. Although pain can arise from the tissues of the abdominal wall that surround the abdominal cavity (such as the skin and muscles), the term abdominal pain generally is used to describe discomfort originating from organs within the abdominal cavity. Organs of the abdomen include the stomach, small intestine, colon, liver, gallbladder, spleen, and pancreas.

Technically, the lowermost portion of the area described previously is the pelvis, which contains the urinary bladder and rectum, as well as the prostate gland in men, and the uterus, Fallopian tubes, and ovaries in women. Often, it can be challenging to know if lower abdominal pain is coming from the lower abdomen or pelvis (pelvic pain).

Occasionally, pain may be felt in the belly even though it is arising from organs that are close to, but not within, the abdominal cavity, for example, conditions of the lower lungs, the kidneys, and the uterus or ovaries. On the other hand, it also is possible for pain from organs within the belly to be felt outside of it. For example, the pain of pancreatic inflammation may be felt in the back. These latter types of pain are described as "referred” because it does not originate in the location where they are supposed. Rather, the cause is located away from where it is felt (i.e., it is referred to as a different area).

The different types of abdominal pain include the following:

• Generalized abdominal pain: Pain that affects more than half of the abdomen is referred to as generalized pain. This type of discomfort is more commonly associated with a stomach illness, indigestion, or gas. If the pain becomes severe, it could be caused by a blockage of the intestines.
• Localized abdominal pain: Pain that is restricted to a single area of the abdomen is called localized pain. It is more likely to indicate an issue with an organ such as the appendix, gallbladder, or stomach.
• Cramps: Pain that feels like a cramp is typically not serious and often caused by gas and bloating. More concerning symptoms include pain that occurs more frequently, lasts longer than 24 hours or is accompanied by a fever.
• Colicky pain: Pain that comes in waves is called colicky pain. It frequently begins and ends abruptly, and it is often severe. This form of stomach pain is commonly caused by kidney stones and gallstones.

Abdominal pain is caused by inflammation of an organ (for example, appendicitis, diverticulitis, colitis), by stretching or distention of an organ (for example, obstruction of the intestine, blockage of a bile duct by gallstones, swelling of the liver with hepatitis), or by loss of the supply of blood to an organ (for example, ischemic colitis).

To complicate matters, however, abdominal pain also can occur without inflammation, distention, or loss of blood supply. An important example of the latter is irritable bowel syndrome (IBS). It is not clear what causes the belly pain in IBS, but it is believed to be due either to abnormal contractions of the intestinal muscles (for example, spasm) or abnormally sensitive nerves within the intestines that give rise to painful sensations inappropriately (visceral hyper-sensitivity). This often is referred to as functional pain because no recognizable specific abnormality to account for the cause of the pain has been found - at least not yet.

As previously mentioned, the discomfort of IBS (irritable bowel syndrome) is due either to abnormal intestinal muscle contractions or visceral hypersensitivity. Generally, abnormal muscle contractions and visceral hypersensitivity are much more difficult to diagnose than other diseases or other health conditions, particularly since there are no typical abnormalities on physical examination or the usual diagnostic tests. The diagnosis is based on the history (typical symptoms) and the absence of other causes.

Doctors will ask you a variety of questions about your belly pain to help find the possible causes of it, for example:

How did the pain begin?

• If it comes on suddenly, this may suggest a problem with an organ within the belly; for example, the interruption of the supply of blood to the colon (ischemia) or obstruction of the bile duct by a gallstone (biliary colic).

Where is the pain located?

• Appendicitis typically causes discomfort in the middle of the abdomen and then moves to the right lower abdomen, the usual location of the appendix.
• Diverticulitis typically causes discomfort in the left lower abdomen where most colonic diverticula are located.
• Discomfort from the gallbladder (biliary colic or cholecystitis) is typically felt in the middle, upper abdomen, or right upper abdomen near the gallbladder.

What is the type and pattern of the pain?

• Is it severe, crampy, steady; or does it wax and wane? Obstruction of the intestine initially causes waves of crampy pain due to contractions of the intestinal muscles and distention of the intestine. True cramp-like pain suggests vigorous contractions of the intestines.
• Obstruction of the bile ducts by gallstones typically causes steady (constant) upper belly pain that lasts between 30 minutes and several hours.
• Acute pancreatitis typically causes severe, unrelenting, boring, steady pain in the upper abdomen and upper back.
• The pain of acute appendicitis initially may start near the umbilicus, but as the inflammation progresses, it moves to the right lower abdomen.
• The character of pain may change over time. For example, obstruction of the bile ducts sometimes progresses to inflammation of the gallbladder with or without infection (acute cholecystitis). When this happens, the characteristics change to those of inflammatory pain.

How long has the pain lasted?

• The discomfort of IBS typically waxes and wanes over months or years and may last for years or decades.
• Biliary colic lasts no more than several hours.
• The pain of pancreatitis lasts one or more days.
• The pain of acid-related diseases - gastroesophageal reflux disease (GERD) or duodenal ulcers - typically occurs over weeks or months that are worse followed by periods of weeks or months during which it is better (periodically).
• Functional pain may show this same pattern of periodicity.

What makes your pain worse?

• Pain due to inflammation (appendicitis, diverticulitis, cholecystitis, and pancreatitis) typically is aggravated by sneezing, coughing, or any jarring motion. Individuals with inflammation prefer to lie still.
• What health conditions make abdominal pain worse or better?

Some doctors suggest that if you have a "less serious" cause of abdominal pain you likely won't need to see a doctor if the symptoms resolve in about 24 to 48 hours. For example, if you have viral or bacterial food poisoning, have had discomfort, but aren't dehydrated.

If you have a chronic problem that occasionally causes abdominal discomfort, most doctors suggest you contact the person treating you for the ailment for an appointment or prescription (refill). However, if you have any of the problems or symptoms listed in the "serious abdominal pain" section above, you should seek immediate medical care.

Doctors determine the cause of the pain by relying on the following:

• Characteristics, physical signs, and other accompanying symptoms
• Findings on physical examination
• Laboratory, radiological, and endoscopic testing
• Surgery

Physical examination

Examining the patient will provide the doctor with additional clues to the cause of the pain. The doctor will determine:

1. The presence of sounds coming from the intestines that occur when there is obstruction of the intestines
2. The presence of signs of inflammation (by special maneuvers during the examination)
3. The location of any tenderness
4. The presence of a mass within the abdomen that suggests a tumor, enlarged organ, or abscess (a collection of infected pus)
5. Blood in the stool may signify an intestinal problem such as an ulcer, colon cancer, colitis, or ischemia

For example:

• Finding tenderness and signs of inflammation in the left lower abdomen often means that diverticulitis is present, while finding a tender (inflamed) mass in the same area may mean that the inflammation has progressed and that an abscess has formed.
• Finding tenderness and signs of inflammation in the right lower abdomen often means that appendicitis is present, while finding a tender mass in the same area may mean that the inflammation has progressed and that an abscess has formed.
• With or without a mass, inflammation in the right lower abdomen may also be found in Crohn's disease. (Crohn's disease most commonly affects the last part of the small intestine, usually located in the right lower abdomen. However, Crohn's disease can affect any part of the gastrointestinal tract.)
• A mass without signs of inflammation may mean that cancer is present.

While the health history and physical examination are vitally important in determining the cause of abdominal pain, other medical tests often are necessary to determine the cause.

Laboratory tests

Laboratory tests such as the complete blood count (CBC), liver enzymes, pancreatic enzymes (amylase and lipase), coagulation studies, pregnancy tests, and urinalysis are frequently ordered.

• An elevated white count suggests inflammation or infection (as with appendicitis, pancreatitis, diverticulitis, or colitis).
• A low red blood cell count may indicate a bleed in the intestines.
• Amylase and lipase (enzymes produced by the pancreas) commonly are elevated in pancreatitis.
• Liver enzymes may be elevated with gallstone attacks or acute hepatitis.
• Coagulation studies may help determine how well the liver is functioning.
• Blood in the urine suggests kidney stones.
• When there is diarrhea, white blood cells in the stool suggest intestinal inflammation or infection.
• A positive pregnancy test may indicate an ectopic pregnancy (a pregnancy in the fallopian tube instead of the uterus).

Plain X-rays of the abdomen

Plain X-rays of the abdomen also are referred to as a KUB (because they include the kidney, ureter, and bladder). The KUB may show enlarged loops of intestines filled with copious amounts of fluid and air when there is intestinal obstruction. Patients with a perforated ulcer may have air escape from the stomach into the abdominal cavity. The escaped air often can be seen on a KUB on the underside of the diaphragm. Sometimes a KUB may reveal a calcified kidney stone that has passed into the ureter and resulted in referred abdominal pain or calcifications in the pancreas that suggest chronic pancreatitis.

Radiographic studies

• Ultrasound is useful in diagnosing gallstones, cholecystitis appendicitis, or ruptured ovarian cysts as the cause of the pain.
• Computerized tomography (CT) of the abdomen is useful in diagnosing pancreatitis, pancreatic cancer, appendicitis, and diverticulitis, as well as in diagnosing abscesses in the abdomen. Special CT scans of the abdominal blood vessels can detect diseases of the arteries that block the flow of blood to the abdominal organs.
• Magnetic resonance imaging (MRI) is useful in diagnosing many of the same conditions as CT tomography.
• Barium X-rays of the stomach and the intestines (upper gastrointestinal series or UGI with a small bowel follow-through) can help diagnose ulcers, inflammation, and blockage in the intestines.
• Computerized tomography (CT) of the small intestine can help diagnose diseases in the small bowel such as Crohn's disease.
• Capsule enteroscopy uses a small camera the size of a pill swallowed by the patient, which can take pictures of the entire small bowel and transmit the pictures onto a portable receiver. The small bowel images can be downloaded from the receiver onto a computer to be inspected by a doctor later. Capsule enteroscopy can help diagnose Crohn's disease, small bowel tumors, and bleeding lesions not seen on X-rays or CT scans.

Endoscopic procedures

• Esophagogastroduodenoscopy or EGD is useful for detecting ulcers, gastritis (inflammation of the stomach), or stomach cancer.
• Colonoscopy or flexible sigmoidoscopy is useful for diagnosing infectious colitis, ulcerative colitis, or colon cancer.
• Endoscopic ultrasound (EUS) helps diagnose pancreatic cancer or gallstones if the standard ultrasound or CT or MRI scans fail to detect them.
• Balloon enteroscopy, the newest technique allows endoscopes to be passed through the mouth or anus and into the small intestine where small intestinal causes of pain or bleeding can be diagnosed, biopsied, and treated.

Surgery

Sometimes, diagnosis requires examination of the abdominal cavity either by laparoscopy or surgery.

Modern advances in technology have greatly improved the accuracy, speed, and ease of establishing the cause of belly pain, but significant challenges remain. There are many reasons why diagnosing the cause of it can be difficult.

Symptoms may be atypical

• For example, the pain of appendicitis sometimes is located in the right upper abdomen, and diverticulitis on the right side. Elderly patients and those taking corticosteroids may have little or no pain and tenderness when there is inflammation, for example, with cholecystitis or diverticulitis. This occurs because corticosteroids reduce inflammation.

Tests are not always abnormal.

• Ultrasound examinations can miss gallstones, tiny ones.
• CT scans may fail to show pancreatic cancer, particularly small ones.
• The KUB can miss the signs of intestinal obstruction or stomach perforation.
• Ultrasounds and CT scans may fail to demonstrate appendicitis or even abscesses, particularly if the abscesses are small.
• The CBC and other blood tests may be normal despite severe infection or inflammation, particularly in individuals receiving corticosteroids or other drugs that suppress the immune system.

Diseases can mimic one another.

• IBS symptoms can mimic bowel obstruction, cancer, ulcers, gallbladder attacks, or appendicitis.
• Crohn's disease can mimic appendicitis.
• Infection of the right kidney can mimic acute cholecystitis.
• A ruptured right ovarian cyst can mimic appendicitis; while a ruptured left ovarian cyst can mimic diverticulitis.
• Kidney stones can mimic appendicitis or diverticulitis.

The characteristics of the pain may change.

• Examples discussed previously include extending the inflammation of pancreatitis to involve the entire abdomen and the progression of biliary colic to cholecystitis.

If you aren't sure if you need to seek medical advice for belly pain, contact your doctor or other healthcare professional before using any home remedies.

Common home remedies and over-the-counter (OTC) medicines include:

• Eat less food
• Take small amounts of baking soda
• Use lemon and lime juice
• Start a BRAT diet (banana, rice, applesauce, and toast) for a day or so for symptom relief
• Avoiding fatty or fried foods
• Don't smoke or drink alcohol

Some healthcare professionals recommend:

• Taking ginger
• Peppermint
• Licorice
• Chamomile tea
• Medications such as bismuth subsalicylate (Pepto-Bismol), loperamide (Imodium), famotidine (Pepcid, Zantac 360), omeprazole (Prilosec), and other over-the-counter substances

Some of these may help reduce symptoms, but if symptoms persist, seek medical care. Beware of "cures" advertised as a single treatment that can cure all causes of this problem because no such remedy or cure exists.

Taking aspirin or NSAIDs should be avoided until the cause of the pain is diagnosed because the medications could worsen some reasons (for example, peptic ulcers, and intestinal bleeding).

Medications that are used for the treatment of underlying cause(s) of the pain are the medications of choice. For example, medications are not needed for the treatment of simple viral gastroenteritis (stomach flu or stomach bug), while surgery and/or chemotherapy may be the best approach to treat certain cancers in the abdomen.

• Other causes may require antispasmodics, antimicrobials, H2 blockers, or even nitrates or morphine. The diagnosed cause usually narrows the choice of medications.
• A few causes can only be treated by surgery (for example incarcerated hernia, abdominal adhesions from previous surgeries, and certain abdominal injuries), although some medications may be used (for example, morphine) while the person is waiting to have surgery.

Lifestyle changes depend on the cause of the pain.

• Eat a healthy diet, exercise, and avoid smoking and excess alcohol consumption to reduce the chances that you will experience specific causes.
• Good hygiene, especially hand washing, and avoiding materials and foods contaminated with viruses and bacteria will reduce your chances of developing illness from many infectious causes.