Introduction

Atresia of the small bowel and colon is a major cause of neonatal small bowel obstruction. Atresia results from an in utero vascular compromise of the intestine. In addition to the atresia, the vascular accident results in other histologic, morphologic and functional abnormalities of the intestine.

Atresia of the small intestine or colon is one of the major neonatal index conditions evaluated and treated by pediatric surgeons. They occur in approximately 1 in 5,000 births. With continued refinement of prenatal ultrasound, the condition is being increasingly diagnosed before birth [1][2]. The pediatric surgeon must therefore recognize the prenatal findings suspicious for intestinal atresia and appropriately counsel parents regarding postnatal evaluation, potential interventions and outcomes. Intestinal atresia constitutes a major etiology in the differential diagnoses of neonatal bowel obstruction which is one of the more common indications for emergency pediatric surgical consultation in the neonatal intensive care unit. The pediatric surgeon must therefore be ready to recognize the spectrum of clinical features and imaging consistent with intestinal atresia and provide urgent interventions to relieve the bowel obstruction and re-establish intestinal continuity where appropriate.

What are the important historical landmarks in our current understanding of intestinal atresia?

Christian Barnard and J.H. Louw of South Africa are credited with providing both experimental and clinical data to support the theory of vascular insufficiency as the major cause of intestinal atresia. Louw provided a thorough review of these data in his Moynihan Lecture delivered to the Royal College of Surgeons of England in 1959, combining his extensive clinical experience acquired at the Hospital for Sick Children on Great Ormond Street with Barnard’s experiments on fetal dogs at the University of Cape Town [3]. Barnard induced vascular injury in canine fetal intestines and upon delivery demonstrated intestinal atresia patterns similar to those found in humans [4]. Remarkably, 80% of the canine fetuses survived to birth decades before the age of fetal surgery [4]. Louw concluded his address by stating “in view of the above considerations it is submitted that the theory of vascular insufficiency accounts for all the clinico-pathological features of congenital intestinal atresia and that there is no need to look for an additional or alternative explanation” [3]. The one possible exception may be Type I atresia, which consists of an imperforate mucosal web which typically occurs in the proximal jejunum. This may in fact share an etiology similar to duodenal atresia - namely failure of recanalization.

The current classification of jejunoileal atresia into 5 types (I, II, IIIa, IIIb, IV) was proposed by Martin and Zerella in 1976 and modified by Grosfeld in 1979 [5]. Several investigators have used other animal models to reproduce intestinal atresia following mesenteric disruption [6]. These models demonstrated several histologic and morphologic abnormalities following the ischemic insult and helped explain the bowel dysfunction and dysmotility seen following the repair of intestinal atresia. To address these issues of poor motility in 1955 Nixon recommended resection of the proximal distended bowel [7]. The techniques of resection and plication enteroplasty were described in an attempt to improve bowel function in cases such as proximal jejunal atresia where complete resection of the distended bowel was not possible [8][9]. Most recently Wales and Dutta described serial transverse enteroplasty in cases of proximal jejunal atresia [9].

see also Intestinal Atresia Repair

Content in this topic is referenced in SCORE Intestinal Atresia overview