examination typically reveals palpable stool in the abdomen The sacrum should be inspected for skin changes suggestive of spinal dysraphism and for an abnormally placed anus Normal deep tendon reflexes and lower extremity strength in conjunction with a normal anal-wink reflex make neurologic impairment unlikely The anus should also be normal in placement and appearance Rectal examination typically yields a dilated vault filled with hard stool Abdominal x-ray can be helpful if the diagnosis of fecal impaction is unclear but is not necessary ( Fig 18.2 ) Failure to thrive is not typically associated with functional constipation and, if present, should prompt further investigation Although functional constipation encompasses most cases of chronic constipation in the child ≥6 months of age, less common causes must always be considered As in the younger infant, endocrine disorders can present as constipation Hypothyroidism is associated with constipation, as well as sluggishness, somnolence, hypothermia, weight gain, and peripheral edema Diabetes mellitus is associated with increased urinary water loss and intestinal dysmotility, which can lead to constipation Hyperparathyroidism and hypervitaminosis D lead to increased serum calcium, which cause constipation through decreased peristalsis Celiac disease is also recognized as a cause of chronic constipation Rarely, an abdominal or pelvic mass may present with chronic constipation Follow-up again is emphasized because a mass that does not resolve after clearance of impaction needs further evaluation Hematometrocolpos can present with constipation and urinary frequency or even urinary retention; therefore, a genital examination is indicated in girls to assess for an imperforate hymen One must also remember that intrauterine pregnancy is a common cause of pelvic mass and constipation in adolescent girls FIGURE 18.2 Both abdominal radiographs demonstrate evidence of constipation with extensive retained fecal material throughout the colon and rectum The rectum in figure (A ) is widened and contains a large fecal impaction while that in figure (B ) is less widened and the stool is less compacted Children with neuromuscular disorders often develop chronic constipation Myasthenia gravis, the muscular dystrophies, and other dystonic states can predispose children to constipation through several mechanisms A detailed history and physical examination should recognize most neuromuscular problems, allowing symptomatic treatment to be provided Psychiatric etiologies must also be considered in the evaluation of constipation Depression can be associated with constipation secondary to decreased intake, irregular diet, and decreased activity Additionally, many psychotropic drugs can cause constipation Anorexia nervosa may present with constipation because of decreased intake, metabolic abnormalities, or laxative abuse causing paradoxical constipation TREATMENT Simple acute constipation in an infant