Meconium Plug Syndrome Imaging
No Results
No Results
processing….
Meconium plug syndrome (also termed functional immaturity of the colon, colonic immaturity, small left colon syndrome, and functional colonic obstruction ) is a transient disorder of the newborn colon characterized by delayed passage (>24-48 hr) of meconium and intestinal dilatation. The incidence is one in 1,000 births, and it is associated with Hirschsprung disease in 40% of cases and cystic fibrosis in 40% of cases. [1, 2, 3, 4, 5]
(See the image below.)
Contrast enema demonstrates the retained meconium as a filling defect or plug that produces a double-contrast effect. Small left colon syndrome is a subset of meconium plug syndrome in which an enema demonstrates an apparent transition zone between the dilated and the normal to decreased caliber distal colon at the splenic flexure. (See the image below.) [1, 2]
The initial imaging modality is plain film radiography, which includes supine and horizontal beam views (left lateral decubitus or cross-table lateral) of the abdomen. Follow plain films with contrast enema. Barium can be used but has been replaced by water-soluble contrast agents in most practices. Historically, Gastrografin was employed, which is a hypertonic solution containing both wetting and detergent agents. However, complications secondary to hyperosmolarity occurred that produced dehydration. Evidence exists that detergent and wetting additives may be toxic, and their possible therapeutic effect remains unproven. [6, 7]
Meconium plug syndrome is a diagnosis of exclusion. Contrast enema usually eliminates congenital small bowel obstruction and rare colon abnormalities (such as atresia and duplication). The primary differential consideration is Hirschsprung disease, which is diagnosed eventually in approximately 10-30% of patients with apparent meconium plug syndrome.
In a study of 33 very low birthweight infants with meconium obstruction, ultrasound-guided water-soluble contrast enema had an overall success rate of 54.5% (18 of 33 successful cases). Patients in the success group had statistically significant older gestational age, larger birth weight, and higher body weight on the day of the procedure. Retrial of contrast injection during the procedure was associated with significantly higher success than the single trial, and the presence of refluxed contrast into the distal ileum was a statistically significant predictor of success. [3]
Rare disorders that may partially simulate meconium plug syndrome include neuronal intestinal dysplasia, visceral neuropathies, and megacystis-microcolon-intestinal hypoperistalsis syndrome, also termed Berdon syndrome. [8] However, radiographic and clinical features in these diseases usually are distinguished readily from meconium plug syndrome. A more common problem is an infant with sepsis or a metabolic disorder who presents with nonobstructive ileus.
Plain films usually demonstrate multiple dilated loops of bowel with absence of rectal gas. The presence or absence of air-fluid levels in the bowel is not helpful. Findings are similar to those of structural colonic or distal small bowel obstruction and help to exclude malrotation with volvulus or obstructing Ladd bands, in which the blockage usually occurs at the duodenum. [6]
Contrast enema usually shows a moderately dilated colon filled with radiolucent material (the meconium plug). In the small left colon variant (see the image below), a transition is seen from a relatively small to normal or increased caliber bowel in the region of the splenic flexure.
Meconium plug syndrome is a diagnosis of exclusion. Contrast enema usually excludes congenital small bowel obstruction and rare colon abnormalities such as atresia or duplication. The main differential consideration is Hirschsprung disease, which is diagnosed eventually in approximately 10-30% of patients with apparent meconium plug syndrome. (See the image below.)
Rare disorders that may partially simulate meconium plug syndrome include neuronal intestinal dysplasia, visceral neuropathies, and megacystis-microcolon-intestinal hypoperistalsis syndrome, also termed Berdon syndrome. However, radiographic and clinical features in these disorders usually are distinguished readily from meconium plug syndrome. A small (micro or mini) colon characterizes many of these diseases.
A more common problem is an infant with sepsis or metabolic disorder who presents with a nonobstructive ileus. In these patients, the intestinal dilatation resolves once the primary problem is treated.
The main problem in differential diagnosis, after the contrast enema has been performed, is Hirschsprung disease. The enema findings in neonatal Hirschsprung disease are not distinguishable from meconium plug syndrome. The most important point is the infant’s response to supportive care and enemas. (See the image below.)
Evaluate any infant with apparent meconium plug syndrome for Hirschsprung disease (rectal-suction biopsy) and other possible underlying disorders when findings persist after 1-2 enemas.
The normal infant’s intestinal gas pattern often appears “gassy” by adult criteria. Typically, the width of a bowel loop does not exceed the width of one of the patient’s lumbar vertebral bodies. Rectal gas often may be absent in the normal infant because the rectum is dependent and filled with meconium when the patient is supine. With the exception of the rectum, the colon and small bowel usually cannot be differentiated on plain film.
American Pediatric Surgical Association. Meconium Plug/Small Left Colon Syndrome. American Pediatric Surgical Association. Available at http://www.eapsa.org/parents/resources/plug.cfm. Accessed: May 11, 2009.
Burge D, Drewett M. Meconium plug obstruction. Pediatr SurgInternational. 2004. 20(2):108-10. [Medline].
Cho HH, Cheon JE, Choi YH, Lee SM, Kim WS, Kim IO, et al. Ultrasound-guided contrast enema for meconium obstruction in very low birth weight infants: Factors that affect treatment success. Eur J Radiol. 2015 Oct. 84 (10):2024-31. [Medline].
Cuenca AG, Ali AS, Kays DW, Islam S. “Pulling the plug”–management of meconium plug syndrome in neonates. J Surg Res. 2012 Jun 15. 175 (2):e43-6. [Medline].
Coppola CP. Meconium plug syndrome and meconium ileus. Coppola CP, Kennedy AP Jr, Scorpio RJ. Pediatric Surgery. Switzerland: Springer International Publishing; 2014. 183-5.
Kim HS, Je BK, Cha SH, Choi BM, Lee KY, Lee SH. Renal excretion of water-soluble contrast media after enema in the neonatal period. Pediatr Neonatol. 2014 Aug. 55 (4):256-61. [Medline].
Carroll AG, Kavanagh RG, Ni Leidhin C, Cullinan NM, Lavelle LP, Malone DE. Comparative Effectiveness of Imaging Modalities for the Diagnosis of Intestinal Obstruction in Neonates and Infants:: A Critically Appraised Topic. Acad Radiol. 2016 May. 23 (5):559-68. [Medline].
Krasna IH, Rosenfeld D, Salerno P. Is it necrotizing enterocolitis, microcolon of prematurity, or delayed meconium plug? A dilemma in the tiny premature infant. J Pediatr Surg. 1996 Jun. 31(6):855-8. [Medline].
Michael J Diament, MD Associate Professor, Department of Radiology, University of California at Los Angeles School of Medicine
Michael J Diament, MD is a member of the following medical societies: American Roentgen Ray Society, Radiological Society of North America, Society for Pediatric Radiology
Disclosure: Nothing to disclose.
Bernard D Coombs, MB, ChB, PhD Consulting Staff, Department of Specialist Rehabilitation Services, Hutt Valley District Health Board, New Zealand
Disclosure: Nothing to disclose.
David A Stringer, MBBS, FRCR, FRCPC Professor, National University of Singapore; Head, Diagnostic Imaging, KK Women’s and Children’s Hospital, Singapore
David A Stringer, MBBS, FRCR, FRCPC is a member of the following medical societies: Royal College of Physicians and Surgeons of Canada, Royal College of Radiologists, Society for Pediatric Radiology, British Columbia Medical Association, European Society of Paediatric Radiology
Disclosure: Nothing to disclose.
John Karani, MBBS, FRCR Clinical Director of Radiology and Consultant Radiologist, Department of Radiology, King’s College Hospital, UK
John Karani, MBBS, FRCR is a member of the following medical societies: British Institute of Radiology, Radiological Society of North America, Royal College of Radiologists, Cardiovascular and Interventional Radiological Society of Europe, European Society of Radiology, European Society of Gastrointestinal and Abdominal Radiology, British Society of Interventional Radiology
Disclosure: Nothing to disclose.
Beverly P Wood, MD, MSEd, PhD Professor Emerita of Radiology and Pediatrics, Division of Medical Education, Keck School of Medicine, University of Southern California; Professor of Radiology, Loma Linda University School of Medicine
Beverly P Wood, MD, MSEd, PhD is a member of the following medical societies: American Academy of Pediatrics, Association of University Radiologists, American Association for Women Radiologists, American College of Radiology, American Institute of Ultrasound in Medicine, American Medical Association, American Roentgen Ray Society, Radiological Society of North America, Society for Pediatric Radiology
Disclosure: Nothing to disclose.
Meconium Plug Syndrome Imaging
Research & References of Meconium Plug Syndrome Imaging|A&C Accounting And Tax Services
Source
0 Comments