Reliability of anorectal manometry in the diagnosis of Hirschsprung's disease

Anorectal manometry was performed in 79 patients, aged 2 days to 19 years, who were referred to us because of constipation or symptoms of intestinal obstruction. A definitive diagnosis was obtained in 75 of the 79 patients (95%). Thus, anorectal manometry is a reliable tool in the diagnosis of Hirschsprung's disease. In the neonatal period, however, a definite diagnosis was possible in only 17 of the 21 neonates (81%). The age at the time of the first examination was 14 +/- 2 days in those with a definite diagnosis and 5 +/- 1 days in those with an indefinite diagnosis (p less than 0.001). If intestinal obstruction can be managed by conservative therapy, examination should be repeated after two weeks of age if the diagnosis before one week of age is not definite. These results indicate that anorectal manometry is non-invasive and reliable in the diagnosis of Hirschprung's disease. However, further examinations such as barium enema or rectal biopsy should be done, even in the neonatal period.