Acute Stomach Pain Important Adult Illnesses
Introduction
Abdominal pain is regarded as pain in the area from just below the xiphoid (lower part of the sternum or “breastbone”) down to the pubis (front of the pelvis)—referred to by many as the “stomach” or “belly.” Acute abdominal pain has a short duration, generally minutes to days and sometimes a few weeks. Pain of longer duration, especially of a few months’ duration, is termed
Pain from organs inside the body tends to be difficult for a person to precisely locate, whereas pain from the muscle, skin, or other parts of the abdominal wall is easier to localize. Also, the same disorder could cause only minor discomfort for some people but be disabling for others. Nevertheless, the location of the pain in the abdomen and its other features can help determine its cause. Accompanying symptoms are also often clues to the underlying illness and its severity; e.g., diarrhea with pain usually points to a gastrointestinal source of pain. The patient’s past medical history can help too; e.g., past abdominal operations, chronic illness, and previous episodes of similar pain. Even a history of certain medical problems in the family is sometimes important. Therefore, physicians consider the patient’s pain description, any associated symptoms, and the general medical context as important background information prior to the physical examination.
If abdominal palpation (examining with the fingers) reveals tenderness that is mainly located in one part of the abdomen, it can be an clue to the diagnosis. Other important findings can include abdominal distension and a mass (enlargement of an organ). The physician also uses a stethoscope to listen to the bowel sounds, noises that the intestine makes that can be abnormal in certain disorders.
The patient’s history (interview) and findings on physical examination usually provide enough information to diagnose the cause of the pain or narrow the possibilities and guide the practitioner to the appropriate diagnostic tests. These are mainly blood and urine tests and procedures that produce images of the organs, such as x-ray examinations, ultrasonography (sound wave-created pictures of the organs), and computerized tomography (CT—cross-section views).
When To Seek Medical Care
Many people have episodes of acute abdominal pain that are exacerbations of a chronic disorder. Pain recurrences that resemble a previously evaluated problem usually do not call for urgent care. With this exception aside, most people should seek medical help for new-onset, acute abdominal pain, especially if it is severe. In general, prompt evaluation is most important for the elderly or people with chronic illness, as it is often more difficult for them than young, previously well people to tolerate disease. This summary cannot be a guide for every circumstance and dependably replace expert evaluation, but the following list comprises types of acute abdominal pain for which obtaining care is usually advisable:
Abdominal pain with fever, weakness, bloody diarrhea, bloody or dark urine, yellow skin or eyes, abdominal distension, light-headedness or passing out, or multiple episodes of vomiting that prevent fluid retention
Abdominal pain that spreads to the shoulder or through to the back
Abdominal pain with heart disease, hypertension, or aortic aneurism
Persistent pain in a hernia; e.g., bulge in the umbilicus (“belly button”) or inguinal area (groin)
Pain and rash in the same area of one side of the abdomen
Abdominal pain with vaginal bleeding
Abdominal pain in pregnancy
Many diseases of the female pelvic organs can cause acute abdominal pain, which gynecologists may call “pelvic pain”; e.g., pelvic infection or rupture of an ovarian cyst or ectopic pregnancy (embryo in a Fallopian tube). The reader should see other sections for information on gynecological pain. This review cannot cover every disease that causes acute abdominal pain, but it briefly describes some important disorders.
Common Causes of Chronic Abdominal Pain: Signs, Symptoms, Diagnosis, and Treatment
Gastrointestinal Disease
Appendicitis—The appendix is a thin, tubular structure averaging about 10 cm in length projecting from the cecum (first part of the large intestine) in the right low abdomen. Collections of lymphocytes (white cells) in its wall play an immunological (infection resistance) role. Obstruction of the appendix can occur from lymphocyte proliferation or a small benign growth that thickens the wall or bits of stool that plug the lumen (open inner area). This blockage impairs the blood supply, which leads to infection in the organ and perhaps perforation with leakage of pus and gas into the abdominal cavity.
Appendicitis occurs in about 9% of males and 7% of females sometime during their lives. Appendicitis typically begins with minor discomfort in the upper or middle abdomen. Since the initial symptoms may not seem serious to patients, they may not seek care until the pain increases and becomes most prominent in the right low abdomen. Nausea and vomiting can follow but usually do not precede pain. As appendicitis worsens, fever can occur. The exact position of the appendix varies, and the location, nature, and severity of the pain are sometimes not typical, so there can be uncertainty in initial diagnosis.
Diagnosis—Typically, examination reveals tenderness in the right low abdomen at an area called “McBurney’s point.” However, the location and degree of tenderness vary. The white blood cell count is elevated or at least shows immature cells in most patients. With a typical history, tenderness, and elevated white cells, appendicitis is likely, but CT or ultrasonography are increasingly used to confirm the diagnosis and exclude other disorders.
Treatment—Immediate appendectomy is usually done when patients are evaluated within 3 days of the onset of symptoms. However, if patients are seen later, especially after more than 5 days of symptoms, most are treated with antibiotics, CT-guided catheter drainage of an abscess (pus collection), if present, and appendectomy a few weeks later. Even with careful evaluation and testing, the diagnosis is sometimes incorrect, leading to removal of a normal appendix. Pelvic infection in women, inflammation in the lower small intestine, and other disorders can mimic appendicitis. Since surgeons know that if they do not remove an inflamed appendix or operate after it has perforated, severe illness or death can result, they expect to err a little on the side of safety and remove a normal appendix about 15% of the time. Traditional “open” (through a conventional abdominal incision) or laparoscopic (assisted by lighted tubes introduced through small incisions) appendectomy are done depending on the specific circumstances.
Acute Gastroenteritis— In this illness, generalized abdominal pain is usually secondary to vomiting and diarrhea in severity. Acute gastroenteritis is second only to the common cold as a cause of lost work time. Viruses cause most cases, and they often spread among family members or more widely in settings like schools, summer camps, and cruise ships. Less frequent bacterial cases are characterized by severe diarrhea, especially with passing blood, and parasites are occasionally the cause. However, even if stool tests are done, the infectious agent is usually not identified. The causative agents are spread mainly by ingesting infected feces, especially in contaminated food or water; hence, the common name, “food poisoning.” The illness is also known as “travelers’ diarrhea” in international visitors, for whom the risk is especially high in Mexico, South and Central America, and most of Asia and Africa.
Young people, particularly babies and elderly adults who are chronically ill or have a defective immune system, are at greatest risk, and many deaths occur in developing countries or wherever treatment, especially intravenous fluids, is not readily available for such patients. Although most victims recover without residual effects, a minority continue to have abdominal discomfort and diarrhea for months or longer due to post-infectious functional dyspepsia or irritable bowel syndrome (see Chronic Abdominal Pain).
Diagnosis—The abdomen is usually tender to examination. The typical symptoms and tenderness generally allow confident diagnosis, especially when the sufferer reports contact with people who have recently had the same illness or has recently visited an area of risk. Laboratory tests are usually not needed. Stool tests are mainly of value when there is fever, severe pain, or bloody diarrhea, recent antibiotic use, or when the patient is hospitalized or has immune deficiency.
Treatment—Drinking lots of fluid is most important. This can usually be pure water—realize that ice can be contaminated—supplemented with saltine crackers to replace salt lost from the body. Sufferers can also purchase without prescription World Health Organization oral rehydration powder and dissolve it in safe water or make their own similar solution: ½ teaspoon salt, ½ teaspoon baking soda, and 4 tablespoons sugar, in 4 ½ cups (1 liter) water. Intravenous fluids are provided when patients are too weak to drink or vomit oral liquids. Anti-diarrhea medication is usually not advised, as it can reduce the frequency of diarrhea by retaining fluid in the bowel, which could cause a patient to falsely think the illness is improving. Antibiotics sometimes speed recovery.
Acute Diverticulitis—Colon diverticula (plural of diverticulum) are protrusions of the inner layers of the colon (large intestine) through the muscle layer, producing small pouches outside the bowel wall, most about ¼ to ½ inch (5 to 10 millimeters) in diameter. Most people with 1 diverticulum have at least a few more, a condition termed diverticulosis. Diverticula predominate in the descending and sigmoid (left side) colon except in Asians who, for unknown reasons, more often have them on the right side. Men and women are equally affected, and their presence increases with age to 50%-70% of people over age 70. Although the reason they develop is not known with certainty, it appears that a low fiber diet over a long period causes the colon to contract more to propel the stool, increasing the pressure inside the colon, which pushes out the diverticula. If a diverticulum develops a tiny perforation (hole), a bit of stool with its bacteria leaks out and infection occurs at that site, the disease known as diverticulitis. Usually, the infection is contained (kept from spreading) by nearby fat and other structures, preventing serious complications. However, about 25% patients have 1 of 4 complications: abscess (pus collection), obstruction (colon blockage), perforation (uncontained leak of gas and infected material outside the colon), or fistula (development of a passage into the urinary bladder or other organ).
Fortunately, only about 15% to 25% of people with diverticulosis will ever suffer diverticulitis. Many people with diverticulosis have chronic abdominal pain, diarrhea, or constipation; however, such symptoms are usually attributable to coincidental irritable bowel syndrome (see Chronic Abdominal Pain).
Since most diverticula are on the left side of the colon, especially the sigmoid portion, most diverticulitis occurs there, resulting in left low abdominal pain. However, Asians are predisposed to right-sided diverticulitis, which can mimic appendicitis. Diverticulitis often begins gradually, so many patients wait a few days before seeking care. Fever, change in bowel habit, nausea and vomiting, and urinary symptoms may occur. This illness tends to recur, so acute symptoms that resemble a previous illness that was diagnosed as diverticulitis likely signal another episode.
Diagnosis—The physician usually detects abdominal tenderness over the inflamed area and may feel a mass. The white blood count is often elevated. Although an ordinary abdominal x-ray can help exclude other disorders as well as a perforation, CT is the most accurate imaging test for diverticulitis. Barium enema x-ray examination is safe in the absence of perforation and may also be diagnostic.
Treatment—Antibiotic therapy is the mainstay, and some patients with mild diverticulitis can be treated without hospitalization. Patients with severe symptoms, those at high risk due to chronic illness or other reasons, and patients with a complication of diverticulitis are hospitalized. Generally, food is withheld or restricted to liquids until improvement is evident. Surgery is required in some patients with uncomplicated diverticulitis, especially those who have had multiple episodes, and nearly all patients with complications, an exception being an abscess that can be drained by a catheter placed through the skin and the rest of the abdominal wall. Endoscopic colon examination (examination through a flexible, lighted tube) is usually done within a few weeks of recovery to exclude other disorders that might have been mistaken for diverticulitis. In the past, many physicians advised a low fiber diet—some may still do this—but there is little evidence that this dietary restriction helps. A moderate- to high-fiber diet makes more sense in light of the reason diverticula seem to form. There is also little support for the idea that avoiding seeds, nuts, and popcorn will prevent a recurrence.
Small Bowel Obstruction—Normally, the small bowel (small intestine) moves the food being digested and absorbed along at an orderly rate. If the small bowel is obstructed, there is a blockage to the flow of its content. About three-fourths of the time, this serious illness occurs from adhesions (bands of scar tissue) and less often from hernias (small openings inside the abdomen or in the abdominal wall through which intestine is caught), tumors, or other causes. Any type of abdominal or pelvic operation performed through a conventional incision can cause adhesions, and one study reported that 15% of patients who had abdominal surgery were hospitalized for this illness within the next 2 years.
Pain in the mid-abdomen that initially fluctuates is typical, and abdominal distension, nausea, vomiting, and subsequent cessation of bowel movements and flatus may occur. Losses of body fluid (“dehydration”) and electrolytes (e.g., salt) occur from vomiting, swelling of the obstructed bowel wall, and failure of intestinal absorption of fluid. If the obstruction becomes complete, strangulation (blockage of blood supply) can lead to necrosis (irreversible bowel damage) and death.
Diagnosis—The characteristic symptoms and examination findings of a tender, distended abdomen with reduced or absent bowel sounds are often diagnostic, but confirmation is obtained with ordinary x-rays or CT. X-rays are sometimes obtained after the ingestion of contrast (liquid that outlines the bowel), and ultrasonography is sometimes done. Blood tests mainly indicate the degree of fluid loss and electrolyte (e.g., sodium and potassium) problems and the likelihood of strangulation.
Treatment—Many patients will recover without surgery, so a trial of non-operative therapy is usual. This treatment includes correction of fluid and electrolyte deficiencies, pain control, and suction of liquid and gas from the stomach. Most patients with incomplete obstruction respond to non-operative treatment, but the majority of patients with complete obstruction need surgery. Overall, the surgical rate is about 25%. Surgeons carefully observe patients and try to determine if obstruction is complete and bowel strangulation is about to occur, in which case emergency surgery can be life-saving. Unfortunately, small bowl obstruction can recur after non-operative or operative treatment, sometimes years later. Some patients, especially those with advanced cancer, may be treated non-operatively for prolonged periods, sometimes with intravenous hyperalimentation (special nutritional fluid), as cure by surgery is unlikely in such patients.
Gallbladder/Pancreatic Disease
Gallstones—The gallbladder stores and concentrates the bile, a yellow liquid produced in the liver, and releases it into the duodenum to aid food digestion. Gallstones are collections in the gallbladder of cholesterol or other natural bile substances that resemble stones. Overall, about 10% of people develop gallstones, and women are 2 or 3 times as likely to get them as men. Some people are at increased risk to develop gallstones, including Hispanics and American Indians, as well as overweight people and those who lose a lot of weight rapidly, such as following stomach surgery for weight loss. Fortunately, most gallstones produce no symptoms, but if they block a duct (small tube) between the gallbladder and the duodenum they can cause severe pain and various complications.
The pain of gallstones is usually in the middle or right part of the upper abdomen, but it can be in the chest, mimicking cardiac pain, or spread to other areas such as the right shoulder or back. It gradually increases and typically lasts for at least an hour. Nausea, vomiting, and sweating are common, and sufferers may move about restlessly trying to be comfortable without success.
Most attacks subside spontaneously, but pain for a few hours or more can indicate acute cholecystitis (inflammation of the gallbladder wall) or pancreatitis (see next section). If a stone blocks the common (main) bile duct, jaundice (yellow discoloration of the eyes and skin) can occur, and sepsis (release of bacteria into the bloodstream) can threaten life. Recurrences of gallstone pain are common, and the majority of people who have their first attack will have more episodes, often every few weeks to months. In fact, this periodic occurrence of attacks helps doctors decide that the pain is coming from gallstones; daily pain for long periods is an unusual feature of gallstones. Belching, flatus, bloating, heartburn, minor abdominal distress, and other nonspecific symptoms can lead to testing that shows gallstones, but they are usually not responsible for these symptoms, and surgery is unlikely to alleviate the symptoms.
Diagnosis—Tenderness is often present in the upper abdomen. If the stones contain enough calcium, they can be seen on ordinary abdominal x-rays or CT scans, but most escape detection by these procedures. Ultrasonography is the most common test. Radioactive scans, magnetic resonance imaging (MRI—a specialized radiology procedure), and endoscopic retrograde cholangiography (an endoscopic procedure that introduces x-ray contrast into the bile ducts) are occasionally needed.
Treatment—Because of the severity of symptoms and possibility of complications, most patients with gallstones that cause pain should undergo cholecystectomy (removal of the gallbladder). In most cases, this surgery can be done as a laparoscopic procedure, using a lighted tube and instruments through small incisions, often with a short hospitalization and quick recovery. A minority of patients require a traditional “open” cholecystectomy through a conventional incision. Serious complications from cholecystectomy occasionally occur, but they are infrequent in healthy people. Removal of stones from the common bile duct may be needed during cholecystectomy or via endoscopy. Rare patients judged to be at unusually high surgical risk are sometimes given a medication that can dissolve gallstones over many months.
Acute Pancreatitis—The primary functions of the pancreas, an organ behind the stomach, are to produce digestive enzymes and insulin. Gallstones and alcohol abuse are the two most common causes of acute swelling and inflammation of the pancreas, the condition termed pancreatitis. A gallstone can leave the gallbladder and travel down the common bile duct en route to the duodenum. The stone can block the pancreatic duct in the head of the pancreas, as the bile and pancreatic ducts converge where bile and pancreatic enzymes are delivered to the duodenum (upper small intestine) through a small opening. In addition to alcohol abuse and gallstones, mumps, trauma, a high triglyceride (blood fat) level, certain drugs, or hereditary factors can cause pancreatitis. In some cases, the cause may be unknown.
Upper and middle abdominal pain rapidly becomes severe and often spreads to the back, and most patient have nausea and vomiting. Body fluid depletion and shock can occur, so prompt medical attention is called for.
Diagnosis—The symptoms, marked abdominal tenderness and elevated blood levels of the pancreatic enzymes, amylase and lipase, usually lead to diagnosis. Ultrasonography can identify gallstones that underlie the disease, and CT can indicate the severity of the illness.
Treatment—Hospitalization with initial withholding of food, intravenous fluid administration, and narcotic pain medication are standard. Sometimes, a nasogastric tube (stomach tube placed thought the nose) is needed to drain the stomach. If the episode is prolonged, feeding a liquid food through a tube into the small bowel is often beneficial, and antibiotics may help severe cases. A majority of patients recover within a few days, but acute pancreatitis can be fatal. Patients with bile duct stones or complications such as pancreatic infection, abscess, or pseudocyst (cyst with certain microscopic features) may require surgical or endoscopic treatment. If gallstones are the cause, cholecystectomy is nearly always advised to prevent recurrences. Underlying alcohol abuse should stop.
Urological Disease
Kidney Stones—Various substances (e.g., calcium and uric acid) are dissolved in the urine and eliminated from the body by the kidneys. Some of these materials can form crystals in the kidney that leave in the urine uneventfully or larger stones that encounter resistance in passing through one of the ureters, the tubes that transport urine from each kidney to the bladder. Such a condition causes acute pain. Occasionally, stones that have produced no symptoms are found on x-ray examinations performed for another problem. About 10% of people will experience a painful kidney stone episode. In the past, men in the United Stated suffered this problem considerably more often than women, but in recent years the male-female difference in kidney stone rates has decreased due to increasing kidney stones in women. The possible causes of kidney stones include metabolic disorders (e.g., diabetes, gout, and hyperparathyroidism), congenital kidney disease, diseases causing chronic diarrhea, chronic urinary infection, certain diets (high in animal fat and salt and low in calcium), and low fluid intake.
The pain varies in severity and location, but can be so severe that narcotics are needed to lessen it. Pain in one side of the abdomen is typical, but it can spread to the testicle or labia as the stone progresses down the ureter. It generally waxes and wanes, a pattern called “colic,” with the most painful periods lasting up to an hour. Nausea and vomiting may occur. Sometimes blood appears in the urine. If the urine is infected, fever may also be present.
Diagnosis—Physical examination is usually not definitive but helps exclude other disorders. The diagnosis is supported by the typical pain profile, a previous diagnosis of kidney stones, or microscopic urine examination showing red blood cells. Some stones can be seen on ordinary abdominal x-rays and x-rays after intravenous administration of a special contrast (dye that appears in urine), but the most accurate test is CT. In pregnancy (radiation can damage the fetus) or when gallstone disease is suspected, ultrasonography is preferred.
Treatment—Therapy for pain is accompanied by passage of most stones 5 millimeters or smaller in size. As the stone increases in size, the chance of passage without special therapy decreases. Medications may be given to facilitate stone passage. For stones that do not pass, special urological procedures are employed including fragmentation of the stone by shock waves transmitted through the body or through endoscopes passed through the urethra, bladder, and ureter. In some cases (e.g., unusually large stones), surgical procedures are needed.
Long-term therapy to prevent recurrent stones includes increased fluid intake to dilute the urine. Additional therapy is based on the contributing factors, which are determined by tests on blood and urine and, of particular value, analysis of the recovered stone itself.
Neurological Disease
Herpes Zoster (“Shingles”)—When a person recovers from chickenpox, the virus can remain in the body in an inactive (non-proliferating) state. Many years later, the inactive virus can reactivate (resume proliferation) in one of the dorsal spinal roots, the nerves that transmit pain and other sensations to the spinal cord, causing pain and rash (“shingles”). About 10% to 20% of people eventually get “shingles,” and the disease increases with age. About 50% of patients are older than 50, and patients who have had organ transplants or who have human immunodeficiency virus (HIV) are at highest risk.
Headache and malaise (general ill feeling) can occur early in the illness. Pain occurs on one side of the body in the affected dermatome (body area sensed by a nerve root). A dermatome of the chest or abdomen is most commonly affected, causing acute chest or abdominal pain. The pain can be constant or intermittent and have various descriptions; e.g., stabbing, burning, deep, or an itching sensation. It varies from mild to severe, and often begins a few days before the characteristic rash appears in a band-like area at the site of pain. The rash starts as a cluster of pink, measles-like spots that become vesicles (tiny blisters), which usually dry up within about 10 days and disappear completely within 1 month. Sometimes only a few vesicles appear, so careful examination is needed.
Diagnosis—When both the typical pain and rash are present, the diagnosis is obvious. When pain is present before the onset of rash, it can cause diagnostic confusion with the pain of cardiac disease, gallstones, kidney stones, or other disorders.
Treatment—Uneventful recovery occurs in most patients. However, post-herpetic neuralgia (chronic pain for months or years) occurs in a minority, especially in older patients. Certain antiviral drugs, especially if started within 3 days of the onset of the rash, can speed recovery; therefore, the earlier the diagnosis and treatment, the better. Medication may be needed for pain. Prevention is best, and the zoster vaccine prevents “shingles” in about 50% of recipients, reduces the severity in many vaccinated people who still develop it, and is recommended for people over 60 years old who do not have immune deficiency, allergy, or another contraindication.
Web sites
American College of Surgeons, http://www.facs.org. Patient education, including illustrated descriptions of common operations.
American Gastroenterological Association, http://www.gastro.org. The AGA Patient Center with information on gastrointestinal disorders.
American Urological Association, http://www.auanet.org. Patient education, including illustrated descriptions of operations, and guidelines for managing specific disorders.
National Institute of Diabetes and Digestive and Kidney Diseases, www.niddk.nih.gov/, NIH site with patient education, including Spanish material, and link to practice guidelines.
National Library of Medicine, www.nlm.nih.gov/medlineplus/healthtopics.html. Comprehensive source of medical information.
UpToDate, http://patients.uptodate.com. Comprehensive information on numerous medical disorders written for the lay public by physician experts.
References
Bresee JS, Widdowson MA, Monroe SS, Glass RI. Foodbourne gastroenteritis; challenges and opportunities. Clinical Infectious Diseases 2002:35;748-753.
Gann JW Jr. Herpes zoster. New England Journal of Medicine 2002:347; 340-346.
Johnson CD. ABC of the upper gastrointestinal tract: gall bladder. British Medical Journal 2001:323; 1170-1173.
Moe OW. Kidney stones: pathophysiology and medical management. Lancet 2006:367; 333-344.
Paulson EK, Kalady MF, Pappas TN. Clinical practice. Suspected appendicitis. New England Journal of Medicine 2003:348;236-242.
Pittman-Waller VA, Myers JG, Stewart RM, Dent DL, Page CP, Gray GA, Pruitt BA Jr, Root HD. Appendicitis: Why so complicated? Analysis of 5755 consecutive appendectomies. American Surgeon 2000: 66; 548-554.
Scales CD Jr, Curtis LH, Norris RD, Springhart WP, Sur RL, Schulman KA, Preminger GM. Changing gender prevalence of stone disease. Journal of Urology 2007:177; 979-982.
Silen, W. Cope's Early Diagnosis of the Acute Abdomen, 21st edition, Oxford University Press 2005
Szojda MM, Cuesta MA, Mulder CM, Felt-Bersma RJF. Review article: management of diverticulitis. Alimentary Pharmacology & Therapeutics 2007:26 (Suppl 2); 67-76.
Teichman JM. Clinical practice. Acute renal colic from ureteral calculus. New England Journal of Medicine 2004:350; 684-693.
Whitcomb DC. Clinical practice. Acute pancreatitis. New England Journal of Medicine 2006:354;2142-2150.