Infants

  • Hirschsprung’s disease

  • Congenital anorectal malformations

  • Neurologic disorders

  • Encephalopathy

  • Spinal cord abnormalities: myelomeningocele, spina bifida, tethered cord

  • Cystic fibrosis

  • Metabolic causes: hypothyroidism, hypercalcemia, hypokalemia, diabetes insipidus

  • Heavy-metal poisoning

  • Medication side effects

Children (older than 1 year)

  • Functional constipation (more than95 percent of cases)

  • Organic causes

    Hirschsprung’s disease

    Metabolic causes: hypothyroidism, hypercalcemia, hypokalemia, diabetes insipidus, diabetes mellitus

    Cystic fibrosis

    Gluten enteropathy

    Spinal cord trauma or abnormalities

    Neurofibromatosis

    Heavy-metal poisoning

    Medication side effects

    Developmental delays

    Sexual abuse