Constipation: Infrequent bowel movements, painful defecation, or larger and harder stools which require excess straining
Functional Constipation: Persistent constipation that is not due to an anatomical or neurologic cause.
Recent Onset Constipation: Lasts for less than 8 weeks. Responds to short term laxatives or behavior modification
Chronic Constipation: Lasts over 3 months. Requires long term laxatives and more intense behavior modification
When is constipation most common in kids?
Introduction of solid foods or cow milk:
Solids can cause constipation due to inadequate fluid and fiber. Fiber can be added with fruits, vegetables, and cereals (but not rice). Adding more than the recommended amount of fiber does not help.
Cow milk can increase the risk of constipation as well as anal fissures. It can be replaced with calcium-fortified soy milk.
Toilet Training:
Children may not respond to need to defecate, and may have difficulty with leverage if their feet don’t touch the ground.
This may lead to withholding, which will cause stools to become larger and harder. Laxatives would be needed to treat this.
Toilet training should be done with a routine, relaxed, child-oriented approach.
School Entry:
Children may be afraid to defecate at school, or the change in schedule may make it more difficult. This may lead to withholding. Also, as children start to use the bathroom themselves, parents may become less aware of their child’s bathroom habits.
Parents should frequently ask about child’s bathroom habits. Furthermore, parents should continue to monitor fiber intake.
Chronic Constipation
Apart from the usual symptoms of constipation, chronic constipation can present with:
Urinary incontinence or bladder disease (since the rectum can push on the bladder)
Weight loss or poor weight gain
Delayed growth
Signs of a chronic condition
Presentation at birth or early infancy
Symptoms outside of the GI tract (especially neurologic conditions)
Physical findings of anorectal abnormalities
Congenital syndromes such as Down Syndrome
Family History of Hirschsprung Disease
Other causes of constipation in children
Infant Dyschezia:
Significant straining and crying before stools in infants in the absence of constipation. Likely due to inadequate relaxation of pelvic floor or weak abdominal muscle tone
This condition usually resolves on its own. Doctors must differentiate this from anal fissures or food-protein induced proctitis.
Hirschsprung Disease
This is a congenital lack of ganglion nerve cells in the colon, so the colon is unable to relax
It is usually diagnosed within the first week of life after a failure to pass meconium. It can present with abdominal distention and vomiting. Rarely, a milder form can present in older children.
It is important that this disease is diagnosed and treated quickly
Other causes of constipation in children
Slow Transit Constipation
Patients have slow movement of food through the colon, without another underlying disease. This is treated with laxatives and behavior modification, but the treatment is less effective than with functional constipation
Anorectal Abnormalities
This can include an imperforate anus or an anteriorly displaced anus. This needs to be treated surgically
Cystic Fibrosis
This is a genetic disorder most common in white children. It is often detected in genetic screens.
As an infant it can present with a failure to pass meconium. As the child grows, they will get recurrent pulmonary infections and pancreatic insufficiency. It can also present with constipation
Celiac Disease
Celiac Disease is a sensitivity to gluten that usually presents with diarrhea. It can, however, also present with constipation.
Constipation in adolescents
Slow-transit constipation is more common in teenagers
Constipation in teenagers may be related to eating disorders, school stressors, and ADHD.
Physical Exam for Constipation
General: Check child growth, weight
Abdomen: Tenderness, distension
Neurologic: Sensory and motor. Tone and reflexes. Cremaster reflex. Patulous (loose) anus suggests sphincter tightening
Perineum: Anorectal development
Digital Rectal Examination:
This is suggested for the following situations
Infants with constipation
Children with constipation since early infancy
Symptoms that suggest underlying disease
Findings
May had explosive release with DRE
Tight anal canal with empty ampulla suggests Hirschsprung Disease
Imaging and Labs
Imaging
Imaging is indicated if history is inadequate and the physical exam is inconclusive or the patient won’t cooperate with the PE
Barium Enema: This can provide evidence of Hirschsprung Disease
Spinal X-Ray/MRI: This should be done if there is evidence of neurologic impairment in the perianal area or lower extremities
Labs
Celiac Screening: Check for celiac with failure to thrive and recurrent abdominal pain
Urinalysis: If there is evidence of rectosigmoid impaction, the bladder may be compressed, which may lead to infection
TSH: If there is evidence of hypothyroidism (poor growth fatigue, depressed reflexes)
Electrolytes: Especially Calcium
Blood Lead Level: For children with risk factors (Living in an old house, relative with lead poisoning)
Treatment
Infants
Sorbitol containing fruit juices such as prune or apple juice can be used. If they are old enough they can get fruit purees.
Infants older than 6 months can be given laxatives such as polyethylene glycol (MiraLAX), sorbitol, or lactulose
Toddlers and children
If defecation is not painful, and increase of fiber (whole grains, fruits, vegetables) and fluids can be given
If defecation is painful, laxatives can be used
If there are anal fissures, they can be treated with petroleum jelly
Disimpaction may be needed (see next slide)
Behavior Modification
Encourage child to sit on the toilet at regular times after meals
The child’s feet should be supported (with a stool if necessary)
Rewards (never punishments) should be given to encourage the child
Disimpaction
Fecal Impaction: Markedly increased stool in the colon and rectum
When should a child be disimpacted?
Constipation-associated fecal incontinence
Significant stool mass felt on digital rectal examination or seen on abdominal X-ray
History of incomplete or infrequent evacuation
How to disimpact
Can be done in the outpatient setting, but hospitalization may be necessary if treatments are unsuccessful
Solutions such as polyethylene glycol or mineral oil can be given through an oral, nasogastric, or rectal route
A combination or oral and rectal is the most effective
Glycerin suppositories or rectal stimulation can be used, but should not be first line , as the child can become dependent on them for defecation
Parent Education
Parents should understand that refusing to defecate or stooling due to overflow incontinence is not “bad” behavior, and the child cannot control it.
In cases of constipation, toilet training should be postponed as will not be effective until the constipation is treated.
Even after constipation is treated, it may take a few months until the nerves readjust and the child learns to use rectal muscles to control defecation
It is important that parents and child regularly follow up with the pediatrician
Bibliography
Sood, Manu. “Recent-onset constipation in infants and children”. UptoDate. June, 2020.
Sood, Manu. “Constipation in infants and children: Evaluation”. UptoDate. June, 2020.
Sood, Manu. “Constipation in infants and children: Treatment”. UptoDate. June, 2020.
Sood, Manu. “Functional constipation in infants, children, and adolescents: Clinical features and diagnosis”. UptoDate. June, 2020.