Severe Pediatric Constipation Clinical Presentation

Updated: Aug 14, 2019
  • Author: Marc A Levitt, MD; Chief Editor: Harsh Grewal, MD, FACS, FAAP  more...
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Constipation after surgery

Children with fecal incontinence after imperforate anus repair can be divided into two categories: those with slow motility and those with fast motility.

Those with constipation (ie, slow motility) after this repair have usually undergone a procedure in which the rectum was preserved (eg, anoplasty, posterior sagittal anorectoplasty, or sacroperineal pull-through procedure); the vast majority of patients fall into this category.

Those with diarrhea (ie, fast motility) after the repair have usually undergone a procedure in which the rectum—and sometimes the sigmoid colon—was resected (eg, abdominoperineal pull-through procedures or endorectal resections). Occasionally, the child has lost a portion of the colon for another reason or has a diarrhea-producing condition.

The patient’s capacity for fecal continence (ie, the ability to hold stool voluntarily) varies according to the type of anorectal malformation (ARM) with which the patient was born. High malformations are often accompanied by poor sphincter muscles, whereas low malformations are usually associated with good muscles.

The degree of hypodevelopment of the sacrum and the presence of associated spinal anomalies contribute to the degree of fecal continence. For instance, a child with a high anomaly and near-normal muscles, sacrum, and spine has a good chance of achieving fecal continence, though this combination is quite rare.

Children who have undergone surgery for Hirschsprung disease often have postoperative constipation, but some have hypermotility. A small group of patients have fecal incontinence as a sequela of the original pelvic operation related to the degree of preservation of their anal canal and their sphincter mechanism.

Functional constipation

Functional constipation is a self-perpetuating and self-aggravating disease. A patient who has a certain degree of constipation that is inadequately treated only partially empties the colon throughout the day, leaving larger and larger amounts of stool inside the rectosigmoid, and this results in greater degrees of megasigmoid. Most surgeons accept that the dilatation of a hollow viscus may lead to impaired peristalsis, which in turn leads to further dilatation. This explains why constipation is due to fecal retention, which produces megacolon that exacerbates the constipation.

The condition is mostly incurable, which means that these patients must be monitored for life. Unfortunately, treatments are frequently administered on a temporary rather than an ongoing basis. Once the treatments are tapered or interrupted, recurrence typically follows. This creates a great deal of frustration for patients and parents and may contribute to the well-known pattern of patients who seek a solution from many different doctors or clinics.

Another controversy involves symptom onset. Many doctors believe that this problem starts during toilet training. Although symptoms become more evident at that time, the motility disorder is often present at birth. Breastfed babies may not show symptoms, because of the well-known laxative effect of human breast milk. When breastfeeding is discontinued and the patient receives formula and other foods, the symptoms become obvious. Babies who have constipation problems while breastfeeding are likely to have severe constipation that will only worsen over time. Some of these patients need to be checked for Hirschsprung disease.

In many instances, parents report that symptoms began in the patient’s preschool years. However, specific inquiries regarding bowel movement patterns since birth often reveal that the constipation actually started very early in life. Typically, the parents remember the first fecal impaction episode most vividly and refer to that event as the initiation of symptoms.

The definition of constipation is another problem. Many pediatricians believe that healthy individuals can go 2-3 days without a bowel movement throughout their lives without having any significant implications. This principle holds true for many individuals; however, when it is applied to a patient who has demonstrated functional constipation, it can interfere with effective treatment.

Though still not universally used in clinical practice, the Rome criteria have been established as the gold standard definition for diagnosing constipation. These criteria have been refined several times. [5] According to the Rome IV criteria for constipation, a patient must have experienced at least two of the following symptoms over the preceding 3 months:

  • Fewer than three spontaneous bowel movements per week
  • Straining for more than 25% of defecation attempts
  • Lumpy or hard stools for at least 25% of defecation attempts
  • Sensation of anorectal obstruction or blockage for at least 25% of defecation attempts
  • Sensation of incomplete defecation for at least 25% of defecation attempts
  • Manual maneuvering required to defecate for at least 25% of defecation attempts

In addition, the Rome IV criteria stipulate that a patient should not meet the suggested criteria for irritable bowel syndrome (IBS) and that loose stools are rarely present without the use of laxatives. [5]

Constipation in infants is manifested by difficult and sometimes painful bowel movements, the presence of hard stool, the passage of bloodstained large pieces of stool, and periods of 2-3 days without passing stool. When these babies receive laxatives, the parents often have to increase the amount of laxatives administered to the point of producing diarrhea before the baby can pass stool. Even with liquid stool, parents describe the babies as being incapable of having bowel movements without some form of rectal stimulation.

The presence of a fissure is the first sign of trouble because it produces painful bowel movements, which tend to make the patient retain stool. Holding the stool for several days produces stool retention, which leads to hardening of the stool. However, the patient eventually passes a larger and harder piece of stool that reopens the fissure, creating a vicious circle. These patients develop a withholding pattern of behavior, a pattern also often seen in children with behavioral problems. If the constipation is not properly treated, it worsens and becomes an increasingly serious problem.

Mild forms of this condition can usually be successfully treated by a pediatrician, who may prescribe a high-fiber diet, foods that act as laxatives, or both. If the diet does not correct the problem, then the pediatrician usually prescribes stool softeners, active-ingredient laxatives, or both.

Stool softeners soften the stool, but do not help it come out, often leading to worsening of the soiling. Laxatives are usually administered in the recommended dosages, which are successful in many patients but not in all patients; this is understandable, given the wide spectrum of severity in this condition. Usually, in the severe cases, not enough laxatives were prescribed.

Fecal impaction is a stressful event characterized by retention of stool for several days, crampy abdominal pain, and, occasionally, proctalgia. A rectal examination discloses the presence of a large mass of rock-hard stool located very low in the rectum.

When laxatives are prescribed to a patient with fecal impaction, the result is an exacerbation of the abdominal pain with severe cramping and, occasionally, vomiting. This is a consequence of increased colonic peristalsis (produced by the laxative) acting against a colonic obstruction (produced by the fecal impaction). It is for this reason that a cleanout is required before a stimulant laxative is started.

Despite the impaction, the patient may pass liquid stool, which is a phenomenon known as paradoxical diarrhea; the liquid stool passes around the solid fecal matter, but the impaction persists. Abdominal radiography can clarify this situation.

Most practitioners recognize and diagnose constipation upon learning that a patient has difficulty passing stool or that a patient has not passed stool in 1-3 days. Another form of constipation that is not recognized by most physicians is characterized by multiple bowel movements throughout the day, consisting of very small amounts of stool. The stool is very sticky and thick and eventually becomes only a smearing or soiling of the underwear. This should also be considered constipation.

Soiling of the underwear without the patient’s awareness is an ominous sign of bad constipation. If a patient who should have achieved bowel control soils his or her underwear day and night and does not have spontaneous bowel movements, he or she has overflow pseudoincontinence (ie, encopresis). Children with this condition behave as fecally incontinent individuals. When the constipation is adequately treated, the great majority of these pseudoincontinent children gain bowel control.

The diagnosis is a clinical one. The symptoms described above are very reliable in establishing the diagnosis. In addition, if a patient presents with symptoms similar to those described above, functional constipation is likely.

Patients with untreated Hirschsprung disease do not soil themselves; in addition, without surgical treatment, Hirschsprung disease causes significant symptoms with distention and enterocolitis, and such patients are frequently malnourished.

Patients with functional constipation do not have true enterocolitis. They occasionally experience episodes of distention and vomiting, similar to what is observed in enterocolitis. However, they actually have fecal impaction and an added picture of viral gastroenteritis that causes severe, crampy, abdominal pain and diarrhea around the impaction.

Patients with Hirschsprung disease who experience actual enterocolitis become extremely toxic and lethargic and may die. Chronic constipation with impressive rectal and sigmoid distention on contrast study can be a rare presentation of Hirschsprung disease, however. To rule out this condition, it is sometimes appropriate to perform anorectal manometry, rectal biopsy, or both (see Workup). 


Physical Examination

Physical examination may reveal a left-lower-quadrant mass, which represents a sigmoid colon filled with impacted stool.

Examination of the rectum is vital for determining impaction. Also, in patients who have undergone surgery, the clinician must rule out the presence of a postoperative anal or rectal or colonic stricture.

The location and caliber of the anus should be evaluated. Patients with ARMs may have an anteriorly placed anus that is incorrectly situated. Previously undiagnosed rectovestibular or rectoperineal fistulae in female patients have been reported. Congenital anal or rectal stenosis, with or without an associated presacral mass, is very rare and may go undetected in the newborn period.