Constipation Diagnosis

  • Diagnosis

    Constipation, the most common gastrointestinal complaint in the U.S., is characterized by infrequent bowel movements. “Normal” bathroom habits can mean different things to different people. A daily bowel movement is not a regular event in everybody’s life. Some people may have three a day while others may have three a week. In general, you are considered to be constipated if you defecate fewer than three times in a week and pass hard, dry stools. However, some constipation sufferers are more bothered by straining and discomfort during defecation than by the reduced frequency of bowel movements.

    Changing your diet and getting more exercise are usually enough to alleviate constipation. However, if you have made lifestyle changes and are still constipated several weeks later, you may wish to consult your doctor. Replacing processed foods with those rich in fiber, drinking more water, and getting more exercise usually relieves constipation. About 80% of people experience constipation at some point in their lives, and brief periods of constipation may be normal. Most people who are mildly constipated do not need laxatives.

    Constipation commonly occurs in children, accounting for as much as 5% of visits to a pediatrician’s office. Infants and children have more frequent bowel movements than adults. Breast-fed infants typically pass three stools/day at age 3 months, and bottle-fed infants pass two stools/day at the same age. Two-year-olds average slightly less than two stools/day, and by the time a child is 4 years old, he or she usually has about one bowel movement/day.

    Constipation in children can present as hard stools, infrequent stools, painful bowel movements, or stool incontinence (loss of bowel control).

    If your child has constipation, most likely your pediatrician will not be able to identify an underlying physical or medical cause. Doctors call this functional constipation. A small percentage of babies and children have an underlying disorder causing constipation. Your child’s doctor should examine your child and do standard tests to exclude any obvious cause, though it is unlikely that your pediatrician will find an underlying medical disorder.

    If you are concerned that your child has constipation, it is important to contact your pediatrician without delay. Prompt diagnosis and treatment improves the overall prognosis of this common condition.

    Constipation is caused by irregular or slowed movement of contents through the lower intestine. For many patients, peristalsis—the intestinal contractions that push contents along—slows and causes partially digested food and other materials to stagnate in the colon or rectum. This allows extra time for the bowel to remove water from wastes, making stools hard, dry, and more difficult to pass.

    Constipation is a consequence of many things, including diet, lifestyle choices, various illnesses, and certain medications Table 01. Inadequate fiber and fluid intake and not getting enough exercise are the main reasons people get constipated. Dietary fiber passes through the intestines without getting digested. It adds bulk to the stool, which stimulates peristalsis. Fiber also soaks up water, which softens the stool and makes it easier to pass. This is why doctors encourage diets rich in fiber. Most people, however, do not get the recommended 20 to 30 grams a day. Drinking water and exercising—other things many Americans do not do regularly enough—softens stool and stimulates contractions in the colon.

    Certain medical problems can also cause constipation.

    Metabolic disorders, such as an underactive thyroid gland, endocrine problems such as diabetes, and neurological illnesses such as Parkinson's disease, are all known to cause constipation. Psychological distress and depression are other recognized offenders. Medications for these and other illnesses can also have a constipating effect. Many drugs used to lower blood pressure include constipation as a side effect, as do antacids that contain aluminum or calcium. Calcium supplements and iron supplements have been known to cause constipation as well.

    Not using the bathroom when you need to can result in impacted stool, and the overuse of laxatives can impair normal bowel function.

    Most children have functional constipation. If the pediatrician cannot find an obvious cause for constipation in your child, then he or she probably has this type of constipation.

    In a small percentage of children, an underlying physical disorder causes constipation. These include a narrow anus or another anatomic defect of the anus; a general medical problem such as thyroid disease, diabetes, cystic fibrosis, nerve damage in the spinal cord, or Hirschsprung’s disease and other disorders of the intestinal muscles; certain medications such as antacids; lead intoxication; and cow's milk intolerance. Your pediatrician may perform a physical exam and appropriate tests to determine if your child has any of these rare causes of constipation.

    Table 1.  Factors That Disturb Bowel Function

    Diet and lifestyle
    Too little fiber in diet
    Inadequate fluid intake
    Laxative abuse
    Sedentary lifestyle
    Not going to the bathroom when urge strikes
    Intestinal obstruction
    Multiple sclerosis
    Parkinson's disease
    Spinal cord injury
    Hypothyroidism (underactive thyroid gland)
    Hypercalcemia (high levels of calcium in blood)
    Hypocalcemia (low levels of calcium in blood)
    Drugs and supplements
    Antacids containing aluminum or calcium
    Anticholinergics (used in treatment of Parkinson?s disease)
    Anti-Parkinson's drugs
    Calcium channel blockers (used in treatment of hypertension)
    Calcium supplements
    Diuretics (used to eliminate water from the body)
    Iron supplements
    Opiates (used to alleviate pain)

    Constipation results in bowel movements that are infrequent, difficult, and painful. People who are constipated may go to the bathroom as little as one or two times a week. The stool they pass may be hard or pellet-like. Pain and excessive straining during defecation are common among people who suffer from constipation. Some report swelling in the abdomen and a feeling of incomplete emptying after a bowel movement.

    Constipated children often have infrequent, hard and painful stools. They may also have stool incontinence that can occur rarely or frequently, or very large stools that fill up the toilet bowl.

    Although constipation can affect all age groups, it tends to be more common in older adults. People 65 years of age and older account for the vast majority of doctor visits for constipation. The elderly have a higher incidence of medical problems that cause constipation.

    In all adult age groups, constipation occurs more frequently in women, with elderly women being the top users of laxatives.

    Risk factors in children include a history of painful defecation and trouble toilet training. Other types of stress can bring on the problem, too. Children who do not eat a well-balanced diet that includes high-fiber fruits and vegetables are also at risk for developing constipation.

    To determine what is causing your constipation, your doctor will start with a medical history and physical exam. He or she will ask you about the nature and duration of your constipation, and will inquire about medications or supplements you may be taking, what kinds of foods you eat, whether you exercise, and if there has been any stress in your life recently. In addition, your doctor will perform a basic physical examination and may take blood and stool samples. Laxatives or enemas may be recommended for a short period of time (no longer than a week).

    If constipation becomes severe, your doctor may wish to perform further tests, such as a barium enema or marker studies.

    Having a barium enema allows the doctor to take x-rays of your colon, which can reveal possible obstructions in the rectum or other parts of the large intestine. To measure the transit time through the large bowel you may be asked to take solid markers contained in a gelatin capsule. X-rays will be taken at different time points to assess the progression of these markers along the large bowel. Your doctor may also recommend that you keep a diary for several weeks in which you record your bowel habits, food intake, exercise, and any other factors that may affect bowel function.

    Other diagnostic tests can show exactly what is happening in your intestinal tract, and can uncover a medical problem that may be causing constipation. If you are over 50, have anemia, or show evidence of blood in your stool, your doctor will perform a sigmoidoscopy or colonoscopy—tests in which a thin, flexible viewing tube is inserted into the rectum to view part or all of the lower intestine. These tests can reveal cancerous and non-cancerous lesions that may be causing constipation.

    Most children have functional constipation. The pediatrician will diagnose a child with this type of constipation if he or she has had at least two of the following problems for two months: two or fewer bowel movements/week; incontinence at least once/week or, for toddlers, incontinence at least once following successful toilet training; excessive stool retention; painful or hard stools; a large stool in the rectum; or very large stools in the toilet.

    If the pediatrician suspects that your child has an underlying cause for constipation, he or she will do a thorough physical exam, particularly of your child’s rectal area, looking for obvious problems. Your pediatrician may want to order blood tests of your child’s blood sugar, thyroid hormone, and lead levels to investigate diabetes, thyroid disease, or lead intoxication as possible causes of constipation. A child with obvious neurological delays may need a thorough evaluation by a neurologist.

    If your infant has had constipation since birth, he or she should undergo a barium enema to rule out Hirschsprung’s disease, a musculoskeletal disorder of the colon. To do this test, a technician gently places an enema with a liquid called barium sulfate into the rectal area. Then a radiologist takes pictures of your baby’s colon to see how well it functions.

    If your doctor is concerned about spinal nerve damage, he or she may order an x-ray of your child’s spine or an MRI to fully evaluate that area of the body.

    A child who develops constipation soon after starting to drink cow’s milk is likely to have an intolerance to it.

    Dietary measures and lifestyle practices can help to keep you regular. The best way to avoid constipation is to make sure you eat enough fiber and drink plenty of water and other non-alcoholic beverages. Shoot for five servings of fiber-rich foods for a total of 20 to 30 grams a day. Fruits and vegetables, whole-grain breads and cereals, and legumes are all excellent sources. Be sure to drink at least eight glasses of water every day and go to the bathroom when you feel the urge.

  • Prevention and Screening

    Dietary measures and lifestyle practices can help to keep you regular. The best way to avoid constipation is to make sure you eat enough fiber and drink plenty of water and other non-alcoholic beverages. Shoot for five servings of fiber-rich foods for a total of 20 to 30 grams a day. Fruits and vegetables, whole-grain breads and cereals, and legumes are all excellent sources. Be sure to drink at least eight glasses of water every day and go to the bathroom when you feel the urge.

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