Meconium ileus
Key points
Cystic fibrosis (CF) Caucasian - 1 in 2500-3500, 1/25 carriers
10-15% CF present with Meconium ileus (MI)
MI rare without CF, but pancreatic ductal stenosis can cause similar findings
40% of meconium peritonitis do not have CF
Meconium plug syndrome
Prematurity
Maternal gestational diabetes and chronic diabetes
Maternal treatment with magnesium sulphate for eclampsia or preterm labour
HD
Often NOT CF
Small left colon syndrome
Localised motility disorder
Associated with maternal diabetes
Should resolve
If not, biopsy for HD
Antenatal features of MI
Hyperechoic bowel, dilated bowel
Cysts
Polyhydramnios
Histology
Microscopically the intestinal glands are dilated, V shaped, and plugged with hypereosinophillic secretions that are in continuity with the desiccated, focally calcified meconium
Normal number of goblet cells in neonates, increased in older
Radiology
AXR features:
No air fluid levels due to sticky meconium
Calcifications
Neuhauser sign
Contrast enema in MI - Unused microcolon with multiple filling defects
Contrast enema in Meconium plug syndrome - Meconium against the colonic wall, creating a double-contrast impression, no microcolon, single large plug, green with pale head
Management
Gastrografin contrast enema (meglumine diatrizoate + sodium diatrizoate)
Hyperosmolar - 1900 mOsm/L
Water soluble
Gastrografin + Omnipaque dose - 15-30ml <10 years - dilute with 2x water
Up to 100ml >10 years
N-acetyl cysteine NG or PR - breaks down sulphide bonds in mucus
Vitamins
Standard scenario
Neonate with distension at birth or antenatal features suggestive of MI
Resuscitation by NICU team
Objectives are to 1. confirm meconium disease 2. Simple or complicated
History:
Antenatal features - bowel dilatation, cysts, polyhydramnios
Family history of CF, differentials: maternal diabetes, opioids
Examination:
Look for differentials e.g. anotrectal malformation
AXR - looking for calcifications, neuhauser sign, lack of air fluid levels
Quote paper 2021 BAPS CASS
Simple: Contrast enema - Omnipaque for diagnosis, Gastrografin if confirmed (Omnipaque is ineffective at decompression) - Give max 3 then laparotomy
Complicated: Primary laparotomy if definite signs
Uncertain: Omnipaque enema
Principles at operation:
Transverse supra-umbilical laparotomy
Washout contamination
Assess bowel length, condition, perforation, atresias, microcolon
Check for volved meconium segment
Decompress - saline and NAC washouts, if not successful, enterotomy
Longitudinal enterotomy at site if dilatation, not within 10cm of ICJ
Milk and wash out meconium
Close transverse
If bowel resected - anastomosis is possibly better than stoma (Described in BAPS CASS - less complications and only 1 recurrent obstruction)
Otherwise divided terminal ileostomy
Post op:
Time to full feeds 2 weeks
NAC TDS via NG
Involve CF team
Vitamins
Start creon when on full feed
References
Parikh NS, Ibrahim SY, Ahlawat R. Meconium Ileus. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK537008/
https://radiopaedia.org/articles/neuhauser-sign-distal-ileum?lang=gb
Wood K, Jinadatha A, Agrawal K, et al
Neonatal small left colon syndrome (NSLCS): Rare but important complication in an infant of diabetic mother
Case Reports 2018;2018:bcr-2017-223456.
Yasir M, Kumaraswamy AG, Rentea RM. Meconium Plug Syndrome. [Updated 2023 Aug 8]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2024 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK562320/
Long AM, Jones IH, Knight M, McNally J; BAPS-CASS. Early management of meconium ileus in infants with cystic fibrosis: A prospective population cohort study. J Pediatr Surg. 2021 Aug;56(8):1287-1292. doi: 10.1016/j.jpedsurg.2021.02.047. Epub 2021 Feb 24. PMID: 33789802.
