[Pathophysiology and treatment of idiopathic chronic constipation with megarectum in children].

Anorectal manometry was carried out in 65 children with idiopathic chronic constipation. Forty-five had no megarectum, and 20 had megarectum. Patients without megarectum showed normal anorectal pressures, recto-anal reflex, rectal sensation and rectal compliance, but motility of the colon was disturbed in these patients. Patients with megarectum also had normal anorectal pressures, recto-anal reflex and rectal sensation, but they showed remarkably high rectal compliance, or excessive rectal reservoir. Patients without megarectum were treated with laxatives and all of them were cured within 6 months after institution of therapy. Patients with megarectum were treated with rectal washout and suppository and 14 out of 20 were cured within 10 months. Six out of 20 patients with megarectum, however, were resistant to conservative therapy and necessity of surgical treatment to reduce the excessive rectal reservoir was proposed for these patients.