The passage of meconium alone is not a sign of correctly positioned anus

Abstract

The passage of meconium is not the only sign of correctly positioned anus. A careful physical examination and awareness of this anomaly are of great importance in making a timely diagnosis of anorectal malformations.

Missed or delayed diagnosis of anorectal malformations: a review of the literature, current training and practice in the UK in relation to detection via the NIPE programme

“…A review of the literature (1994–2020) on missed or delayed diagnosis of ARM, excluding case reports, revealed 18 publications, with 4 from the UK and Ireland 4–18 23–26. Keywords used for search strategy were: anorectal malformation, missed, delayed, diagnosis, morbidity, mortality, trend and outcome.…”

“…Unfortunately, there have been reports of fatalities due to this complication 14 16. A collated review of the published literature where this has been clearly reported5 7 8 11 14 16 17 shows that worldwide the incidence of bowel perforation when there has been a missed/delayed diagnosis is 18.0% (68/376) and mortality has been 4.5% (17/376). Similar calculations for the UK and Ireland4 11 16 17 show that the incidence of bowel perforation was 3.1% (n=5/162) and of deaths was 1.9% (n=3/162).…”

“…While the reasons for this are likely related to training and education, clinical experience, the environment, workload and resources available (see below 'education and training issues' section), other practical reasons for a failure to detect an abnormal anus during examination of the perineum are shown in box 1. History of passage of meconium or finding meconium in the nappy can mislead the examiner into thinking that the anus is normal, highlighted by several publications with eye-catching titles such as ‘Missing anus: do not miss it’,36 ‘The passage of meconium alone is not a sign of correctly positioned anus’8 and ‘don’t be fooled by meconium’ 37…”

“…Affecting both males and females, these anomalies vary in their appearance and presentation, lack features enabling antenatal detection and should be detected at birth by the examining midwife3 or within 72 hours through the newborn and infant physical examination (NIPE) screening programme. It is recognised that the diagnosis of ARMs can be missed or delayed leading to morbidity and mortality 4–18…”

Variations in the Detection of Anorectal Anomalies at Birth among European Cities

“…Perineal examination in a neonate can be challenging, particularly in females, and anal patency is often usually assumed by the presence of meconium in the nappies rather than introduction of a probe in the anus. 11,12 To provide a measure of the rate of missed ARMs in the newborn period, in this study, we review all new cases of ARM born in the United Kingdom and presenting to two pediatric surgery tertiary referral centers over a period of 15 years. The data were compared with two tertiary centers in Europe (which have different guidelines on postnatal checks).…”