Constipation

Constipation in a young child as seen by X-ray. Circles represent areas of fecal matter (stool is opaque white surrounded by black bowel gas).
ICD-10	K59.0
ICD-9	564.0
DiseasesDB	3080
MedlinePlus	003125
eMedicine	med/2833
MeSH	D003248

Constipation also known as costiveness^[1], dyschezia,^[2] and dyssynergic defaecation^[2] is a symptom^[2] of infrequent hard to pass bowel movements.^[2] Defecation may be painful, and in severe cases (fecal impaction) may lead to symptoms of bowel obstruction. The term obstipation describes severe constipation which prevents passage of both stool and gas. Causes of constipation include dietary, hormonal, anatomical, as a side effect of medications (e.g., some opiates), and poisoning by heavy metals. Treatments may include changes in dietary habits, laxatives, and enemas.

[edit] Definition

Types 1 and 2 on the Bristol Stool Chart indicate constipation

The definition of constipation includes the following:^[3]

• infrequent bowel movements (typically three times or fewer per week)
• difficulty during defecation (straining during more than 25% of bowel movements or a subjective sensation of hard stools), or
• the sensation of incomplete bowel evacuation.

[edit] Children

After birth, most infants pass 4-5 soft liquid bowel movements (BM) a day. Breast-fed infants usually tend to have more BM compared to formula-fed infants. Some breast-fed infants have a BM after each feed, whereas others have only one BM every 2–3 days. Infants who are breast-fed rarely develop constipation.^[4]

By the age of 2 years, a child will usually have 1-2 bowel movements per day and by 4 years of age, a child will have one BM per day.^[5] An infant who has a BM every 2–3 days is not constipated as long as the stools are soft and pass easily.

Constipation in children usually occurs at three distinct points: after starting formula or processed foods (while an infant), during toilet training in toddlerhood, and soon after starting school (as in a kindergartner) ^[6]

[edit] Causes

The causes of constipation can be divided into congenital, primary, and secondary.^[2] The most common cause is primary and not life threatening.^[7] In the elderly, causes include: insufficient dietary fiber intake, inadequate fluid intake, decreased physical activity, side effects of medications, hypothyroidism, and obstruction by colorectal cancer.^[8]

[edit] Primary

Primary or functional constipation is ongoing symptoms for greater than 6 months not due to any underlying cause such as medication side effects or an underlying medical condition.^[9][2] It is not associated with abdominal pain thus distinguishing it from irritable bowel syndrome.^[2] It is the most common cause of constipation.^[2]

[edit] Medication

Many medications have constipation as a side effect. Some include: diuretics and those containing iron, calcium, aluminum, opioids (e.g., codeine, loperamide, and morphine) and certain tricyclic antidepressants

[edit] Metabolic

Metabolic and endocrine problems may lead to constipation including: hypercalcemia, hypothyroidism, and diabetes mellitus.^[7]

[edit] Structural abnormalities

A number of anatomical problems may lead to constipation including: spinal cord lesions, Parkinsons, colon cancer, anal fissures, proctitis, and pelvic floor dysfunction.^[7] The most common medical disorder associated with constipation in infants is hirschsprung's disease.

[edit] Psychological

Some infants become apprehensive and because of fear that it may be painful, thus withhold stools. Sometimes, small children feel shy and do not feel safe or comfortable about having a bowel movement.

[edit] Diet

Also, constipation may appear in infants after having changed from breast milk to regular milk or formula, or having switched from baby food to solid food.

Other common causes of constipation in children include a diet that does not include a significant amount of fiber, not drinking enough fluids, illness, psychological issues or the parent having previously punished the child for an accident that she or he had.

[edit] Diagnostic approach

The diagnosis is essentially made from the patient's description of the symptoms. Bowel movements that are difficult to pass, very firm, or made up of small hard pellets (like those excreted by rabbits) qualify as constipation, even if they occur every day. Other symptoms related to constipation can include bloating, distension, abdominal pain, headaches, a feeling of fatigue and nervous exhaustion, or a sense of incomplete emptying.^[10]

Inquiring about dietary habits will often reveal a low intake of dietary fiber or inadequate amounts of fluids. Constipation as a result of poor ambulation or immobility should be considered in the elderly. Constipation may arise as a side effect of medications, including antidepressants, which can suppress acetylcholine^[11][12] and opiates, which can slow the movement of food through the intestines^[13]. Rarely, other symptoms suggestive of hypothyroidism may be elicited.^{[citation needed]}

During physical examination, scybala (manually palpable lumps of stool) may be detected on palpation of the abdomen. Rectal examination gives an impression of the anal sphincter tone and whether the lower rectum contains any feces or not; if so, then suppositories or enemas may be considered. Otherwise, oral medication may be required. Rectal examination also gives information on the consistency of the stool, presence of hemorrhoids, admixture of blood and whether any tumors, polyps or abnormalities are present. Physical examination may be done manually by the physician, or by using a colonoscope.

X-rays of the abdomen, generally only performed on hospitalized patients or if bowel obstruction is suspected, may reveal extensive impacted fecal matter in the colon, and confirm or rule out other causes of similar symptoms.

Chronic constipation (symptoms present at least three days per month for more than three months) associated with abdominal discomfort is often diagnosed as irritable bowel syndrome (IBS) when no obvious cause is found. Physicians caring for patients with chronic constipation are advised to rule out obvious causes through normal testing.^[14]

Colonic propagating pressure wave sequences (PSs) are responsible for discrete movements of the bowel contents and are vital for normal defecation. Deficiencies in PS frequency, amplitude and extent of propagation are all implicated in severe defecatory dysfunction (SDD). Mechanisms that can normalise these aberrant motor patterns may help rectify the problem. Recently the novel therapy of sacral nerve stimulation (SNS) has been utilized for the treatment of severe constipation.^[15]

[edit] Prevention

Constipation is usually easier to prevent than to treat. The relief of constipation with osmotic agents, i.e., lactulose, polyethylene glycol, or magnesium salts, should immediately be followed with prevention using increased fiber (fruits, vegetables, and grains) and a nightly decreasing dose of osmotic laxative. With continuing narcotic use doses of osmotic agents may safely be used.^{[citation needed]}

There is insufficient evidence that physical exercise is useful in chronic constipation to recommend it for this purpose generally, because "exercise only offers symptomatic improvement in chronic constipation to the elderly."^[16]

[edit] Treatment

The main treatment of constipation involves the increased intake of water, and fiber (either dietary or as supplements).^[7] The routine use of laxatives is discouraged, as having a bowel movement may come to be dependent upon their use. Enemas can be used to provide a form of mechanical stimulation. However, enemas are generally useful only for stool in the rectum, not in the intestinal tract.

[edit] Laxatives

If laxatives are used milk of magnesia is recommended as a first-line agent due to its low cost and safety.^[7] Stimulants should only be used if this is not effective.^[7]

In cases of chronic constipation prokinetics may be used to improve gastrointestinal motility. A number of new agents have shown positive outcomes in chronic constipation including: prucalopride^[17], and lubiprostone.^[18]

[edit] Physical intervention

Constipation that resists the above measures may require physical intervention such as manual disimpaction (the physical removal of impacted stool using the hands).

[edit] Children

Lactulose and milk of magnesia have been compared with polyethylene glycol(PEG)in children. All had similar side effects, but PEG was more effective at treating constipation.^[19][20] Osmotic laxatives are recommended over stimulant laxatives.^[21]

[edit] Prognosis

Straining to pass stool may lead to hemorrhoids. In later stages of constipation, the abdomen may become distended, hard and diffusely tender. Severe cases ("fecal impaction" or malignant constipation) may exhibit symptoms of bowel obstruction (vomiting, very tender abdomen) and "paradoxical diarrhea", where soft stool from the small intestine bypasses the mass of impacted fecal matter in the colon.

[edit] Epidemiology

Constipation is the most common digestive complaint in the United States as per survey data.^[22] Depending on the definition employed, it occurs in 2% to 20% of the population.^[7][23] It is more common in women, the elderly and children.^[23] The reasons it occurs more frequently in the elderly is felt to be due to an increasing number health problems as humans age and decreased physical activity.^[9]

[edit] In animals

Hibernating animals can experience tappens that are usually expelled in the spring. For example, bears eat many foods that create a "rectal plug" before hibernation.

Canines may also experience constipation, which they usually attempt to repair by ingesting grass and other plant materials.

[edit] References

[edit] External links

• 09-129b. at Merck Manual of Diagnosis and Therapy Home Edition
• Constipation - Introduction (UK NHS site)
• MedlinePlus Overview constipation
• Constipation Guideline - the World Gastroenterology Organisation (WGO)
• Constipation treatment guide - Canadian Society for Gastrointestinal Endoscopy
• Relieving Severe Constipation - Constipation symptoms, treatment and prevention of this uncomfortable condition

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article "Constipation".