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Parents are often preoccupied with how and how often their children move their bowels, but most constipation has no serious consequences and should be a concern only when passing stools becomes painful and leads to further withholding of stools, or when constipation causes other symptoms.
In infants, bowel movements vary so much in frequency that it is difficult to define constipation. The same infant who generally has a bowel movement 4 times/day may, at other times, have one every 2 days. Most infants pass a hard, large stool with minimal discomfort, while some cry when passing a soft one. In general, signs of effort (eg, straining) do not signify constipation; infants only gradually develop the muscles to assist a bowel movement. In neonates, inability to pass meconium within 24 h suggests Hirschsprung's disease (see Congenital Gastrointestinal Anomalies: Hirschsprung's Disease). In infants, inability to pass stool for several days combined with other symptoms and signs, such as increase in abdominal girth and signs of pain, should raise suspicion of rare disorders (eg, Hirschsprung's disease or obstruction from a tumor).
In older children, constipation is defined as the passing of hard stools that cause discomfort and is most often caused by insufficient dietary fiber. The condition may be self-reinforcing, because discomfort while moving bowels causes further withholding of stool.
At any age, passage of hard stools can cause anal fissure. Fissures cause severe pain on defecation and the occasional passage of a small amount of bright red blood. Diagnosis of external fissures is by inspecting the anus; no assessment is necessary for internal fissures because treatment of constipation relieves symptoms. Most fissures heal quickly without intervention, but increased fluid intake and a stool softener may facilitate healing.
Evaluation
History:
History focuses on frequency and consistency of stools, presence or absence of discomfort on defecation, presence or absence of blood, and composition of the diet, especially fluids and fiber. Reports of constipation going back to birth and refractory to conventional therapy suggest an anatomic defect, such as Hirschsprung's disease. Reports of painful defecation suggest an anal fissure. Reports of poor fluid intake suggest a dietary factor.
Physical examination:
Examination focuses on the abdomen and anus. A distended abdomen or abdominal mass suggests a significant problem with stool retention, an obstruction, or rarely, a tumor. A crack or split in the anal skin establishes the diagnosis of an anal fissure. Finding hard stool at the end of the examining finger suggests that Hirschsprung's disease is not the problem.
Testing:
Tests are ordered if history and examination suggest obstruction (as in Hirschsprung's disease) or tumor. Tests may include x-rays, CT scans, or MRI to define intra-abdominal masses, and rectal manometry and biopsy for Hirschsprung's disease. (See also the North American Society for Pediatric Gastroenterology and Nutrition's position statement Constipation
in Infants and Children: Evaluation and Treatment.)
Treatment
Most often, increases in dietary fluid and fiber (with whole grains, fruit, or supplements) are sufficient; temporarily reducing milk intake may help. Young children who are toilet trained often become distracted and typically do not sit long enough on the toilet to pass constipated stool. Parental guidance to sit longer and more frequently (eg, at least twice/day for 10 min after meals) establishes a routine that gives the child the opportunity to defecate fully. Stool softeners and laxatives (eg, senna 5 to 10 mL once/day for children < 6 yr and bid for those > 6 yr; Mg hydroxide 0.5 mL/kg once/day for children < 2 yr, 5 mL tid or 15 mL once/day for children 2 to 5 yr, 5 to 10 mL tid or 15 to 30 mL once/day for those 5 to 12 yr), as well as gentle enemas, are available and safe and can facilitate the process, though they may be required for several months before normal defecation returns permanently. In one regimen, laxatives or softeners are given for 2 to 3 wk, then every other day for 1 mo after initial catharsis, then daily for 1 to 2 wk if relapse occurs.
Last full review/revision November 2005
Content last modified November 2005
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