Overview
Definition:
Functional constipation in children is defined by the Rome IV criteria as the presence of two or more of the following symptoms for at least one month in a child aged 4-15 years: infrequent stools, hard or large stools, painful or hard stools, large diameter stools, significant fecal impaction in the rectum, or passage of large-volume stools that may obstruct the toilet
It excludes organic causes and is characterized by the absence of organic disease explaining the symptoms
Long-term management focuses on achieving regular bowel movements, preventing impaction, and improving quality of life.
Epidemiology:
Functional constipation is a common pediatric problem, affecting an estimated 0.7% to 29.6% of children worldwide, with higher prevalence in primary care settings
It is more common in children aged 2-4 years and may persist into adolescence
There is no significant gender predilection in younger children, but it may be more prevalent in boys in some studies
Factors such as diet, lifestyle, and toilet training practices influence prevalence.
Clinical Significance:
Untreated or inadequately managed functional constipation can lead to significant morbidity, including fecal incontinence (soiling), abdominal pain, urinary tract infections due to bladder compression, decreased appetite, poor weight gain, and psychosocial distress for both the child and family
It is a frequent reason for pediatric outpatient visits and can place a substantial burden on healthcare resources
Effective long-term management is crucial for preventing these complications and improving the child's well-being.
Clinical Presentation
Symptoms:
Infrequent bowel movements (less than 3 per week)
Straining or difficulty passing stools
Passage of hard, dry, or pellet-like stools
Large stools that may clog the toilet
Fecal soiling (encopresis) due to overflow incontinence
Abdominal pain, often relieved by passing stool
Decreased appetite or poor feeding
Nausea or vomiting (less common)
Avoidance of defecation due to pain or fear.
Signs:
Abdominal distension
Palpable fecal impaction in the abdomen or rectum on digital rectal examination
Soiling of underwear with liquid stool
Large, distended colon on abdominal palpation
Reduced anal tone in severe cases
In rare instances, a palpable mass may be present
Normal vital signs are typical unless complications are present.
Diagnostic Criteria:
Rome IV criteria for functional constipation in children (aged 4-15 years) require at least two of the following, occurring at least once per week for at least one month: Infrequent stools (less than 3 per week)
Straining with defecation
Hard or large stools
Fecal impaction in the rectum
Large-volume stools that may obstruct the toilet
One or more episodes of fecal incontinence per week
Insufficient stools or incontinence to explain the diagnosis
Absence of criteria for irritable bowel syndrome
In infants and toddlers (under 4 years), criteria are adapted and include infrequent stools, large stools, or large fecal mass in the rectum, with or without encopresis, occurring at least once per week for at least one month, with no organic cause.
Diagnostic Approach
History Taking:
Detailed history of bowel habits: frequency, consistency (Bristol Stool Scale), straining, pain
Onset and duration of symptoms
Toilet training history and practices
Dietary habits (fiber, fluid intake)
Physical activity
Medications
History of anal fissures or painful defecation
Soiling episodes: timing, volume, frequency
Family history of constipation or gastrointestinal disorders
Red flags: failure to thrive, bloody stools (without anal fissure), fever, bilious vomiting, abdominal distension suggesting obstruction, neurological deficits, thyroid dysfunction, celiac disease, Hirschsprung's disease (suspect in neonates/infants with delayed meconium passage).
Physical Examination:
General examination: assess growth parameters (height, weight) and look for signs of systemic illness
Abdominal examination: assess for distension, tenderness, and palpable fecal masses
observe for perianal skin irritation or excoriation
Digital rectal examination (DRE): assess anal tone, presence and consistency of stool in the rectal vault, and any associated pain or anal fissures
This is a crucial step to assess for impaction and rule out organic causes like Hirschsprung's disease.
Investigations:
Generally, investigations are not required for diagnosis of functional constipation when clinical criteria are met and red flags are absent
However, if red flags are present or treatment is refractory: Plain abdominal radiography (X-ray) may show fecal loading, but is not diagnostic
Ultrasound of the abdomen can assess for stool burden and rule out other pathologies
Laboratory tests: complete blood count (anemia), thyroid function tests (hypothyroidism), celiac screening (tissue transglutaminase antibodies), electrolytes, calcium, and phosphate
Plain abdominal X-ray may be useful if impaction is suspected and not palpable on DRE.
Differential Diagnosis:
Hirschsprung's disease (especially in infants with delayed meconium passage)
Intestinal malrotation with volvulus
Meconium ileus
Hypothyroidism
Hypercalcemia
Neurological disorders (e.g., cerebral palsy, spinal cord abnormalities)
Anal stenosis or stricture
Inflammatory bowel disease (less common)
Irritable bowel syndrome (Rome IV criteria help differentiate)
Lead poisoning (rare)
Metabolic disorders.
Management
Initial Management:
Disimpaction: If significant fecal impaction is present, disimpaction is necessary
This can be done with oral laxatives (e.g., high-dose PEG 3-5 days), rectal administration of laxatives (e.g., mineral oil enemas), or manual dislodgement under sedation if required
Education and counseling: Reassurance for parents and child regarding the benign nature of functional constipation and the importance of long-term treatment
Toilet training program: Regular scheduled toilet sits (10-15 minutes after meals) to encourage defecation
Positive reinforcement and avoidance of punishment.
Medical Management:
Osmotic laxatives: Polyethylene glycol (PEG) 3350 is the first-line choice for long-term maintenance therapy
Dosage: typically 0.25-1.5 g/kg/day, titrated to achieve soft stools (e.g., Bristol Stool Scale type 4-5) at least daily or every other day
Lactulose is another option, but can cause more bloating and gas
Stimulant laxatives: Senna, bisacodyl
Used short-term for disimpaction or intermittently if osmotic laxatives are insufficient
Long-term use of stimulants is generally discouraged due to potential for dependence and electrolyte disturbances, though some evidence suggests safety in carefully monitored long-term use
Stool softeners: Docusate sodium or mineral oil are less effective for chronic management compared to PEG.
Long Term Regimen Comparison:
Polyethylene Glycol (PEG): Generally considered the gold standard for long-term maintenance due to its safety profile, efficacy, and ease of use
It works by drawing water into the stool, making it softer and easier to pass, thereby reducing pain and encouraging regular bowel habits
Titration of dose is key
Stimulant Laxatives (e.g., Senna, Bisacodyl): Act by stimulating intestinal motility
They are very effective for acute disimpaction
Long-term use is controversial
while some studies show safety, the primary concern is potential for dependence and electrolyte imbalances
They are often used in combination with osmotic laxatives or for rescue therapy
Evidence suggests that PEG is superior for long-term adherence and efficacy in functional constipation.
Supportive Care:
Dietary modification: Increase fluid intake and dietary fiber (fruits, vegetables, whole grains)
Consider a fiber supplement if dietary intake is insufficient
Behavioral modification: Encourage regular physical activity
Establish a regular toileting routine
Positive reinforcement for successful bowel movements
Psychological support: Address anxiety and fear associated with defecation
Family counseling is essential for adherence and management
Monitor for adherence, side effects, and effectiveness of the chosen regimen.
Complications
Early Complications:
Fecal impaction leading to overflow incontinence (encopresis)
Acute bowel obstruction (rare, due to severe impaction)
Anal fissures and pain on defecation
Urinary tract infections (UTIs) due to mass effect
Rectal prolapse (rare).
Late Complications:
Chronic encopresis and fecal incontinence
Persistent abdominal pain
Psychosocial distress, low self-esteem, social isolation
Avoidance behaviors related to defecation
Refractory constipation despite treatment
Bladder dysfunction (e.g., urgency, frequency, hesitancy) secondary to chronic constipation.
Prevention Strategies:
Early recognition and prompt treatment of constipation
Consistent long-term management with appropriate laxatives and behavioral strategies
Adequate fluid and fiber intake
Regular physical activity
Positive and supportive toilet training practices
Regular follow-up with healthcare providers to monitor progress and adjust treatment.
Prognosis
Factors Affecting Prognosis:
Adherence to treatment regimen
Family support and engagement
Severity and duration of constipation
Presence of psychosocial factors
Absence of underlying organic disease
Appropriate management of fecal impaction and soiling
Timely initiation of treatment.
Outcomes:
With appropriate and consistent management, the prognosis for functional constipation is generally good
Most children achieve symptom resolution and return to normal bowel function
Long-term outcomes include improved quality of life, reduced abdominal pain, cessation of soiling, and resolution of psychological distress
However, relapses can occur, requiring ongoing monitoring and management
A small percentage may have persistent symptoms into adulthood.
Follow Up:
Regular follow-up is crucial, especially in the initial months of treatment, and can be spaced out as the child stabilizes
Frequency depends on severity, but typically involves visits every 1-3 months initially, then every 6-12 months for stable patients
Follow-up should assess bowel movement frequency and consistency, presence of pain, straining, soiling, and impact on quality of life
Medication adherence, diet, and behavioral strategies should be reviewed
Discontinuation of laxatives should be gradual and only after prolonged symptom-free periods, under medical supervision.
Key Points
Exam Focus:
Rome IV criteria are essential for diagnosis
PEG 3350 is the preferred first-line agent for long-term maintenance therapy due to its safety and efficacy
Disimpaction is the first step in cases of fecal impaction
Red flags warrant thorough investigation to rule out organic causes
Long-term management requires a multimodal approach including pharmacotherapy, behavioral modification, and dietary changes
Stimulant laxatives are best for short-term use or disimpaction.
Clinical Pearls:
Always assess for fecal impaction with a digital rectal exam
Educate parents that laxatives are not habit-forming and are necessary for re-establishing normal bowel function
Compliance is often the biggest challenge
simplify the regimen and involve the child in treatment decisions
Address the fear of pain
regular, soft stools are key
Remember that soiling is often due to overflow, not intentional soiling, and resolves with proper management.
Common Mistakes:
Underestimating the severity of impaction
Inadequate disimpaction
Discontinuing laxatives too soon or too abruptly
Punitive approaches to toilet training or soiling
Not addressing psychosocial factors
Relying solely on stimulant laxatives for long-term management
Failing to investigate red flags adequately.