Results: RAIR: Sensitivity 94.74% (73.97 - 99.87%) Specificity 96.08% (86.54 - 99.52%); Positive predictive value 90% (69.73 - 97.23%); Negative predictive value 98% (87.9 - 99.7%) Conclusion: Anorectal manometry is a simple, safe, and non-invasive method with high specificity for the diagnosis of Hirschsprung disease in neonates.