Constipation

Overview

Constipation is a typical complaint in the pediatric context. For many children, constipation is functional in origin, coming from a pattern of infrequent or incomplete stool output (ie, inadequate stool evacuation), and involves behavioral issues such as stool withholding. In many cases of functional constipation (FC), the pattern may have begun during or before toilet training in the toddler years and is now well established. Inadequate water and fiber, as well as an overabundance of dairy or carbs, are frequently contributing causes.

Constipation is a sign of an underlying organic disease process in a tiny proportion of instances. Most organic issues may benefit from laboratory investigations and imaging. In the absence of an organic process, FC can be managed by correctly educating families on the nature of FC, as well as paying close attention to dietary fiber and fluid intake, using stool softeners and laxatives, and making behavioral changes.

Normal Bowel Habit in Children

It is acknowledged that children's bowel habits vary significantly from one another. In a UK-based study of 350 pre-school children (ages 1-4), 96 percent of the youngsters had bowel movements between three and four times each day. Stool frequency varies with age. Although there may be a variation in stool frequency between breast and bottle fed newborns, the time to first stool after meconium passage is the same in both groups.

Pediatric Functional Constipation (FC)

Functional constipation (FC) is a prevalent condition in children, with an estimated global frequency of 3%. Constipation is classified as FC if there is no underlying organic reason, which occurs in up to 95% of children. It may be seen in healthy children aged one year and above, and it is more frequent in preschool-aged children. Most people have bowel movements at regular intervals, and while the frequency varies, feces should pass without substantial straining or discomfort.

Functional constipation is frequently described as difficult or infrequent bowel movements/difference from normal frequency, painful defecation, the passage of hard stools, and the sense of incomplete stool evacuation. It is frequently unrelated to any underlying systemic cause or anatomical abnormality. Environmental factors, stress, food, coping abilities, and social support are all common contributors.

Causes of idiopathic constipation in children

Understanding the cause of constipation in children is critical. This might happen as a result of insufficient evacuation due to hurrying to school in the morning, fast use of the school bathroom, or the youngster delaying stools because they are preoccupied with something more important. Children may occasionally have hard stools as a result of decreased fluid intake following a febrile illness or during a holiday trip.

Constipation is more common in children who struggle with toilet training. These youngsters may be less adaptive and have a pessimistic attitude. 74% would hide the stool, while 37% would want pull ups to keep the stool in place. Instead of confrontation, these youngsters gain more from regular reinforcement via star charts/other incentive strategies.

Secondary constipation, such as that caused by hypothyroidism, Hirschsprung's disease, or changes in calcium levels, is uncommon, accounting for fewer than 10% of cases. Cow's milk protein allergy, particularly non-IgE mediated allergy with accompanying colonic dysmotility, can appear as secondary constipation, with one research putting its frequency as high as 40% of refractory constipation.

Up to 63% of children with constipation and fecal soiling had a history of painful feces before the age of three, as well as subsequent withholding behavior. Stool withholding occurs after a difficult bowel movement, resulting in a vicious cycle of pain that leads to additional withholding, stool hardening and increase in size with subsequent megarectum, absence of defaecatory signal, and so on. Parents may misinterpret such withholding as straining.

Pathophysiology

Holding feces instead of emptying the colon causes stool buildup. The colon eliminates water from feces, making it more difficult to pass. As feces builds up, the smooth muscles in the gut walls stretch and become less effective. The cycle of stool holding, water removal from the stool, and smooth muscle stretching in the gut culminates in hard stools that are big and difficult to evacuate, producing further stool retention. If this becomes a chronic problem, a patient's rectum fills with hard feces on a regular basis, and they lose the sensation of needing to urinate. Encopresis occurs when soft stool leaks around the harder “plug”

Symptoms of Constipation

• Infrequent stools

Reduced bowel movement is a typical diagnostic indicator. In one research of 178 children with constipation in Iowa, 58 % had three bowel movements per week, while in another, 41 % of children with constipation symptoms had infrequent stools. Constipation was present in children aged 2 years, with symptoms of passage of hard or pebble-like stools, straining, withholding, or painful defecation. If just infrequent stools were utilized for diagnosis, 50% of the time the diagnosis would be missed.

• Pain

Children may complain of abdominal discomfort or difficulty defecating. In one research, 33 percent of children with constipation experienced non-specific stomach discomfort. Painful defecation occurs when children complain of discomfort or cry during or before feces, which has been recorded in up to 68 percent of constipated children. They may pass blood via their stools.

• Soiling

Fecal incontinence has been linked to 'constipation' in up to 90% of cases. Soiling is involuntary, usually minor and stains the underwear; but, if large enough, it might be confused with diarrhea. Medications may be erroneously lowered when they should be maintained or increased.

• Stool withholding maneuvers

This might be misconstrued as straining. Back-arching in babies is common, as is standing on toes, stretching legs, or swaying back and forth to avoid anal relaxation in older infants/toddlers. Some kids may seek refuge in a corner, standing stiffly or crouching.

• Blood in stools

In older children, fissures can cause bleeding and painful feces. After wiping, children may appear with blood on tissue paper. Infection/cellulitis, fissures, fistulae, or tags should all be looked for during a perineal examination. The latter, which is associated with slowed growth or delayed puberty, may be indicative of Crohn's disease. In comparison, children with polyps frequently appear with painless bleeding. Rectal hemorrhage in childhood is frequently caused by a cow's milk protein allergy rather than constipation.

• Enuresis and other urinary symptoms

Urine symptoms have been observed in 9-13 percent of children with constipation, including urinary incontinence in 10.5 percent, and it has been linked to enuresis. In children with enuresis, asymptomatic constipation may aggravate urine symptoms. The impacted feces in the rectum compresses the bladder, reducing its functional capacity and causing an early urge to urinate. Furthermore, prolonged pelvic floor spasm hinders full voiding relaxation and adds to postvoid residuals.

• Associations:

Obesity  

Obesity has been reported to be more prevalent in constipated children than in the overall paediatric population, with related psychological concerns, poor nutrition, low exercise levels, and compliance challenges.

Poor Fluid intake

NICE recommends optimal fluid intake as a crucial adjuvant in the treatment of constipation. Excessive fluid intake, on the other hand, might lead to a decrease in fiber consumption, which can be harmful.

Diagnosis of Pediatric Constipation

functional constipation is defined separately for infants and children greater than 4 years of age. 

In Infants Up to 4 Years

Must include 1 month of at least 2 of the following or 2 or fewer defecations per week:

1. History of excessive stool retention
2. History of painful or hard bowel movements
3. History of large-diameter stools
4. Presence of a large fecal mass in the rectum

In toilet-trained children, the following additional criteria may be used:

1. At least 1 episode/week of incontinence after the acquisition of toileting skills
2. History of large-diameter stools that may obstruct the toilet

For Children Greater than 4 Years

Must contain two or more of the following happening at least once per week for at least one month with inadequate criteria for an irritable bowel syndrome diagnosis:

1. 2 or fewer defecations in the toilet each week in a youngster of at least 4 years of age
2. At least one fecal incontinence event every week
3. Retentive posture or excessive volitional stool retention in the past
4. a history of unpleasant or difficult bowel motions
5. A big fecal mass is present in the rectum.
6. Large diameter stools that might impede the toilet have a history.

The symptoms cannot be adequately explained by another medical condition after proper investigation.

Irritability may be indicative in a kid with an underlying neurological disease or developmental delay, and a high index of suspicion should be maintained, since constipation may be present in the setting of gut dysmotility. Constipation may be overlooked in one-third of autistic children if clinical criteria alone are used to reach a diagnosis. Other implications include a link between refractory constipation and maltreatment in children, however traits such as soiling should be considered in context and are not discriminating in isolation.

Investigations

Often, tests are unnecessary and are simply performed to rule out secondary constipation. The initial blood test, which includes thyroid and celiac disease screening, may include a dietary evaluation. Specific IgE to cow's milk is not indicative of cow's milk allergy in children with constipation.

Children who do not react to therapy, have an unusual history, or have concerns on physical examination may need more information or referral to a professional. A TSH can be used to screen for hypothyroidism, and a lead level can be useful if lead poisoning is a concern. Hirschsprung disease should always be considered, particularly in extremely young, chronic, or unusual cases.

• Plain abdominal X ray

Constipation is a clinical diagnosis, not a radiological one. A plain abdomen x-ray is occasionally useful in instances of diagnostic doubt, however it is very subjective.

• Ultrasound (USS)

Because the transverse width of the rectal ampulla grows with age, the USS measurements in both the patient and control groups were impacted. In all age categories, the numerical values of this measure differed considerably between patients and controls. The rectopelvic ratio is defined as the ratio of the width of the rectal ampulla (on USS) to the distance between the anterior superior iliac spines (measured externally with a measuring tape) and has been used to define 'megarectum.'

• Anorectal/Colonic Manometry

This is not a first-line investigation, but it has been utilized in children with refractory symptoms, typically after many medications have failed, who may have required multiple hospitalizations for therapy. The existence of high-amplitude contractions with a gastro-colonic response suggests that neuromuscular function is intact. Children with intestinal pseudo-obstruction had the highest rate of motor disorders. Colonic manometry can help with surgical planning in children with refractory symptoms.

• Rectal biopsy

The gold standard for diagnosing Hirschsprung's disease is a deep suction rectal biopsy. Hirschsprung's disease is extremely uncommon if the development of constipation occurs after the newborn era. Ultra-short Hirschsprung's disease is uncommon and was originally described in 1958 by Davidson and Bauer. Strip biopsies are advised to avoid artificially negative results. A full thickness biopsy is preferred over a strip biopsy because it includes mucosa from the dentate line to the rectum.

Treatment of Pediatric Constipation

• Non-Pharmacological

Normal fiber and hydration consumption, as well as moderate physical exercise, are suggested for children with constipation. In addition to traditional treatment, there is no evidence to support the routine use of intense behavioral protocolized therapy programs or biofeedback. There is no evidence to suggest that prebiotics or probiotics can be used to relieve constipation.

Adequate fluid intake, as well as age-appropriate exercise, are needed. Children who have been toilet trained should be encouraged to sit on the toilet and try to have a bowel movement for 5 to 10 minutes after the same meal, at the same time of day, every day; this will take advantage of the gastrocolic reflex and reduce the risk of constipation by "training" the child to have a bowel movement every day. A follow-up session should be scheduled in 1 to 3 weeks to assess the success of the treatment and to discuss any required adjustments to the treatment plan.

However, Acute management of Constipation include:

• Disimpaction

The initial stage of therapy is to clear the colon of hard stool, a process called as disimpaction. The removal of impacted, hard stool permits the colon to resume normal size and function. Manual removal, suppositories, and enemas were once prominent procedures used during this stage of therapy. Because of its effectiveness, safety profile, and tolerability, polyethylene glycol (PEG) has become the first therapy of functional constipation.

The amount of PEG advised during the cleanout phase of the treatment routine varies, but a suitable dose would be 1 to 1.5 grams of PEG per kilogram combined with 6 to 8 oz. water or juice. Significantly greater dosages have been utilized, particularly in hospitals. If feasible, patients should be urged to consume this over a three-hour period. If there is no notable response to this medication, the patient can take it again the next day. If there is no response after two days of medication, or if there is substantial stomach discomfort, prolonged vomiting, or other concerns, the family should come in for a check-up and reevaluation.

• Maintenance Therapy

The purpose of the second phase of therapy is to maintain the stool very soft, preventing hard stool reaccumulation while the colon restores to normal size and function. Oral medicines are used in this period.

1. Osmotic laxatives:

• Polyethylene glycol (PEG) at 0.2-0.8 g/Kg/day
• Lactulose at 1- 3 mL /kg/day
• Magnesium hydroxide at 0.5-3 mL/kg/day

2. Stool Softeners:

• Docusate sodium at 5 mg/kg/day
• Mineral oil (lubricant) at 1-3 mL/Kg/day

3. Stimulant laxative for rescue therapy in addition or alone (duration less than 30 days):

• Senna at 2.5-7.5 mL/day
• Bisacodyl at 5-10 mg/day

Management of difficult/refractory constipation

To rule out an organic etiology, an initial history and examination should be performed at the first session, followed by active investigations (as previously described). If these show indications of sluggish colonic transit, this might indicate a neurological disease of the gut, which would necessitate colonic manometry and a full thickness biopsy for a conclusive diagnosis.

As previously noted, ongoing extrinsic problems such as bullying, dysfunctional family relationships, and child abuse should be taken into account. Similarly, children with neurological/psychiatric disorders may struggle to learn/stick to a toileting schedule. Non-punitive behavioral therapies in combination with pharmaceutical and dietary treatment is recommended. An inpatient stay might be beneficial. A multidisciplinary team, including nurses with experience managing constipated children, can help with this. Psychologists and play therapists can teach relaxation techniques for toileting, and dieticians can advise on fluid intake and fiber content.

Differential Diagnosis

Constipation can be caused by anatomic anomalies such as anal atresia and presacral tumors, metabolic diseases such as hypothyroidism, cystic fibrosis, lead intoxication, or neurologic illnesses such as meningomyelocele and Hirsprung disease. Constipation can also be caused by toxins such as botulinum toxin (found in honey) and drugs such as opiates. Irritable bowel syndrome is also a factor in older children.

Red Flags Concerning for an Organic Disorder

• Fever, stomach distention, weight loss or poor weight growth, reduced appetite, and bloody diarrhea are examples of systemic symptoms.
• Onset before one month of age
• Delayed passage of meconium
• Failure to thrive
• Intermittent diarrhea and explosive stools
• Abnormal neurological examination such as low tone, loss of cremasteric reflex, and decreased lower extremity reflexes.
• No response to treatment

Most of these illnesses may be ruled out with a comprehensive history and physical exam. A history of lower extremities weakness or incontinence raises the possibility of a neurologic etiology. Children under the age of one year who are not growing normally or who do not respond to treatment may require extra testing. The abdominal exam and lower extremity neurologic test should get specific focus throughout the physical exam.

A spinal exam should search for symptoms of neural tube abnormalities such as hemangiomas and big dimples with midline hair tufts. The anus should be examined to confirm that its look and placement are normal. A rectal exam can be painful, but it can detect rectal tone, hard stool in the vault, and a huge presacral lump. Growth curves should be examined for symptoms of growth failure or alterations in the curve.

Prognosis

Following initial therapeutic success, a large number of relapses have been documented. Relapses have been observed to be more prevalent in boys than in girls. However, the prognosis for constipation in children under the age of five is favorable, with constipation resolved in 88 % of children in this age range when observed for eighteen months.

Non-responders came from households with a higher level of psychosocial issues, and medication adherence was questioned. In general, half of children with chronic constipation will be treated after a year, and 65-70 percent will be cured after two years, with substantially greater rates in motivated, devoted families. According to two studies, 34-37 percent of people are still constipated three to twelve years after starting therapy.

Conclusion 

Constipation is still a common condition that has a negative influence on children's quality of life and creates a strain on primary and secondary care. More patient and parental education and support, as well as improved toileting habits, increased fiber, and optimized laxatives, have the potential to provide a considerable benefit to children and revolutionize what may otherwise be a difficult and stressful disease.