Current significance of meconium plug syndrome
Scott J. Keckler, Shawn D. St. Peter⁎, Troy L. Spilde, KuoJen Tsao,
Daniel J. Ostlie, George W. Holcomb III, Charles L. Snyder
Department of Surgery, The Children's Mercy Hospital, Kansas City, MO 64108
Received 28 November 2007; accepted 3 December 2007
Background: The significance of meconium plug syndrome is dependent on the underlying diagnosis.
The incidence of pathologic finding, particularly Hirschsprung's disease, contributing to the presence
of these plugs, has been debated. However, there are little recent data in the literature. Therefore, we
reviewed our experience with meconium plugs as a cause of abdominal distension to evaluate the
associated conditions and incidence of Hirschsprung's disease.
Methods: We reviewed the records of newborns with meconium plugs found in the distal colon on
contrast enema from 1994 to 2007. Demographics, radiologic findings, histologic findings, operative
findings, and clinical courses were reviewed.
Results: During the study period, 77 patients were identified. Mean gestational age was 37.4 weeks and
birth weight, 2977 g. Hirschsprung's disease was found in 10 patients (13%). One had ultrashort segment
disease and another had total colonic aganglionosis. Maternal diabetes was identified in 6 patients. No
patients were diagnosed with cystic fibrosis, meconium ileus, malrotation, or intestinal atresia.
Conclusion: Meconium plugs found on contrast enema are associated with a 13% incidence of
Hirschsprung's disease in our experience. Although all patients with plugs and persistent abnormal
stooling patterns should prompt a rectal biopsy and genetic probe, the incidence of Hirschsprung's and
cystic fibrosis may not be as high as previously reported.
© 2008 Elsevier Inc. All rights reserved.
Neonatal bowel obstruction typically presents with
abdominal distension, emesis, and failure to pass meconium
within the first 24 hours. Differential diagnosis includes
Hirschsprung's disease, malrotation, meconium disease, and
intestinal atresia. Meconium plug syndrome is most often a
benign cause of obstruction that clears after rectal stimulation
or administration of contrast enema; however, the presence
of meconium plugs may herald underlying intestinal
pathologic nature. Literature on the topic is scattered and
widely variant in the reported incidence of significant
pathologic finding. The initial reports describing meconium
plug syndrome documented a 13% incidence of Hirsch-
sprung's disease and no association with cystic fibrosis [1,2].
However, for the past 40 years, the literature has reflected
different results with Hirschsprung's in as many as 38% and
cystic fibrosis in as many as 43% of patients with meconium
plug syndrome [3,4]. Therefore, we performed a retro-
spective analysis to review the coexistence of meconium
Presented at the 39th Annual Meeting of the Canadian Association of
Pediatric Surgeons, August 23-26, 2007, St John's Newfoundland, Canada.
⁎Corresponding author. Center for Prospective Clinical Trials, Depart-
ment of Surgery, Children's Mercy Hospital, 2401 Gillham Road, Kansas
City, MO 64108, USA. Tel.: +1 816 983 3575; fax: +1 816 983 6885.
E-mail address: firstname.lastname@example.org (S.D. St. Peter).
0022-3468/$ – see front matter © 2008 Elsevier Inc. All rights reserved.
Journal of Pediatric Surgery (2008) 43, 896–898
plugs and their relationship with Hirschsprung's disease
meconium ileus and other pathologic finding.
Retrospective review of the medical record was per-
formed on all patients diagnosed with a meconium plug
identified in the rectum on contrast enema from January
1994through February 2007. During the study timeframe, 77
patients were identified. Gestational age, birth weight,
passage of meconium, bilious vomiting, abdominal disten-
sion, associated anomalies, and maternal diabetes were
recorded. The presence of meconium ileus, small descending
colon, a transition zone, malrotation, and intestinal atresias
on contrast enema were recorded. Results of suction rectal
biopsies and studies performed to diagnose cystic fibrosis
were recorded. Operative interventions, total length of stay,
and outcome were reviewed.
Mean estimated gestational age was 37.4 ± 2.4 weeks
with a mean birth weight of 2977 ± 693 g. Sex distribution
included 48 males and 29 females. Abdominal distension
followed by bilious emesis was the most common clinical
presentation. A history of maternal diabetes was present in
6 patients (7.8%). Mean age at presentation was 1.49 ±
0.92 days. Spontaneous passage of meconium in the first
24 hours occurred in 15 patients (19.5%). No cases of
meconium ileus or intestinal atresia were identified. At the
initial diagnostic contrast enema, a diagnosis of small
descending colon was made in 27 patients (35.1%). A
transition zone was identified in 13 patients (16.9%), of
which 9 (11.7%) were diagnosed with both small descending
colon and a transition zone.
Patients with a persistent abnormal stooling pattern
underwent suction rectal biopsy resulting in 22 biopsies in
the same number of patients (28.6%). Thirteen of these
patients had a transition zone identified on the contrast study.
Hirschsprung's disease was confirmed histologically in 9
patients from the suction rectal biopsy performed in the
neonatal period, of which 4 patients had a transition zone
identified on the contrast study. One additional patient was
identified as having Hirschsprung's disease by balloon
manometry at 4 years of age. Thus a total of 10 patients
were found to have an aganglionic segment in this series
representing 13.0% of the study population. Of these
10 patients, 8 had the typical rectosigmoid transition,
1 patient had ultrashort segment disease, and 1 patient had
total colonic aganglionosis. All have undergone definitive
procedures with no mortality, and all are currently doing
well. The patient with ultrashort segment underwent internal
sphincterotomy that has alleviated the constipation.
A total of 25 patients underwent investigation for cystic
fibrosis, with 22 gene probe analysis and 3 sweat chloride
tests, of which none had positive results.
The term meconium plug syndrome was first reported by
Clatworthy  in 1956 to describe the colonic obstruction
because of inspissated meconium. Initial nonsurgical man-
agement was recommended as most of these patients were
treated effectively with rectal stimulation or contrast enema.
This original report was later updated with additional
patients 10 years later, in which the authors recommended
rectal biopsy to rule out Hirschsprung's disease if normal
bowel function did not occur after passage of the plug .
Small descending colon syndrome has been associated
with meconium plug syndrome since the initial report .
The association of diabetic mothers giving birth to babies
with small descending colon syndrome was subsequently
recognized with an incidence of 40% to 50% [5,6]. Although
our findings superficially support these studies as 3 of
6 diabetic progeny had small descending colon seen on
contrast enema, this study has only a subset of diabetic
mothers and does not address the entire denominator of
The clinical presentation ofmeconium plugsyndrome and
meconium ileus is similar, although the source of meconium
obstruction is at 2 separate locations. In our series, patients
with typical meconium ileus appearing as ileal obstruction
with proximal small bowel dilatation and microcolon were
not included as meconium plug syndrome patients. In the
past, cystic fibrosis, the usual cause of meconium ileus, has
found an impressive 24% who were found to have the cystic
fibrosis mutation . Recently, an even higher incidence
(43%) appeared in the literature . We found no association
with cystic fibrosis and meconium plug syndrome in our
series. This contrasting result may relate to the definition of
meconium plug syndrome. None of the contrast enemas in
our series had meconium plugs in the small intestine, only in
the colon. In the previous report with a 24% incidence of
cystic fibrosis, no mention of the anatomical location of the
meconium is stated . This implies that patients may have
been included with ileal plugs. In the other report, meconium
plug syndrome is in fact defined as meconium located in the
colon but does not speak of whether the population is
meconium exclusively in the colon . That we had no
patients with cystic fibrosis supports a theory that a
meconium plug obstruction in the colon is a different disease
entity than one located in the distal small bowel as previously
The recognition that Hirschsprung's disease may be the
cause of the meconium plugs has been recognized since the
897Current significance of meconium plug syndrome
initial description was published (Table 1). That initial report Download full-text
of 30 patients found 13.3% had an aganglionic segment,
which is identical to our series and similar to another small
series of 8 patients with meconium plugs of which the result
of 2 suction rectal biopsies were aganglionic . The low
incidence of Hirschsprung's disease historically reported
was recently contradicted in a report of 21 patients with
meconium plugs, of whom 38% were diagnosed with
Hirschsprung's disease concluding that this association
may be higher than has been historically reported . This
study precipitated our investigation. Our series represents the
largest series ever compiled on meconium plug syndrome by
more than2-fold. In addition, thedataset isrecently compiled
thus representing current diagnostic knowledge and technical
expertise of radiologists at a high-volume dedicated
children's hospital. Of the 77 patients in our series with
meconium plug syndrome, 10 patients (13.0%) were
ultimately diagnosed with Hirschsprung's disease, a number
identical to the initial series published 40 years ago . The
distribution of disease is about what would be expected from
any 10 Hirschsprung's patients with most demonstrating
rectosigmoid transition with one very short and one very
long (total colonic). This distribution implies that Hirsch-
sprung's diagnosed after meconium plug syndrome may be
any level of disease that is an important fact for the
counseling surgeon. The favorable outcomes after the
definitive operation from our series have also been reported
Based on this large, contemporary review, the presence of
a meconium plug on contrast enema most often correlates
with a benign clinical course. However, in the presence of an
abnormal stooling pattern, further workup is indicated. When
meconium plug syndrome is identified carefully as pellets
only present in the colon, then a diagnosis of cystic fibrosis
may be a rare event. It appears that the incidence of
Hirschsprung's disease remains around 13% as initially
reported when the syndrome was defined.
 Clatworthy Jr HW, Howard WHR, Lloyd J. The meconium plug
syndrome. Surgery 1956;39:131-42.
 Ellis DG, Clatworthy Jr HW. The meconium plug syndrome revisited.
J Pediatr Surg 1966;1:54-61.
 Burge D, Drewett M. Meconium plug obstruction. Pediatr Surg Int
 Olsen MM, Luck SR, Lloyd-Still J, et al. The spectrum of meconium
disease in infancy. J Pediatr Surg 1982;17:479-81.
 Philippart AI, Reed JO, Georgeson KE. Neonatal small left colon
syndrome: intramural not intraluminal obstruction. J Pediatr Surg 1975;
 Davis WS, Campbell JB. Neonatal small left colon syndrome.
Occurrence in asymptomatic infants of diabetic mothers. Am J Dis
 Casaccia G, Trucchi A, Nahom A, et al. The impact of cystic fibrosis on
neonatal intestinal obstruction: the need for prenatal/neonatal screening.
Pediatr Surg Int 2003;19:75-8.
 Van Leeuwen G, Riley WC, Glenn L, et al. Meconium plug syndrome
with agangliosis. Pediatrics 1967;40:665-6.
syndrome with Hirschsprung's disease
Previous published association of meconium plug
Series No. of
Ellis et al 
Van Leeuwen et al 
Burge et al 
898 S.J. Keckler et al.