Congenital duodenal and multiple jejunal atresia with malrotation in a patient with Down syndrome.

Abstract

Congenital duodenal atresia (CDA) is a relatively common anomaly affecting an estimated 1 in 3000 to 10 000 births and is strongly associated with Down syndrome (Coran et al. 2011a, b; Adams and Stanton, 2014; Alnosair et al. 2014; Zaghal et al. 2015). Intrinsic CDA is thought to result from failure of recanalization of the duodenum (Alnosair et al. 2014). Congenital jejunoileal atresia (CJIA) affects approximately 1 in 5000 to 14 000 births (Adams and Stanton 2014; Zaghal et al. 2015). More than one-third of affected children are born prematurely, and associated chromosomal abnormalities are rare (<1 % of cases) (Adams and Stanton 2014). CJIA is thought to result from an intrauterine vascular accident (Coran et al. 2011a, b; Adams and Stanton 2014; Alnosair et al. 2014; Zaghal et al. 2015). No reports have described the simultaneous occurrence of duodenal and multiple jejunal atresia, malrotation, an annular pancreas, and the absence of branches of the superior mesenteric artery in a patient with Down syndrome. To our knowledge, this is the first such case report. The patient was referred to our institute because two intra-abdominal cysts exhibiting the “double-bubble” sign were detected by fetal ultrasonography at 29 gestational weeks. This finding was confirmed at our institution by fetal magnetic resonance imaging, which revealed a dilated stomach and first portion of the duodenum. The patient, a female infant, was delivered at 35 gestational weeks with a body weight of 2352 g. She had the typical features of Down syndrome. Based on the radiologic and ultrasonic findings, she was preoperatively diagnosed with CDA, malrotation without volvulus, and a ventricular septal defect. She underwent laparotomy at 0 days of age. She had type III duodenal atresia (i.e., the third and fourth parts of the duodenum were absent), type IV multiple jejunal atresia, malrotation, an annular pancreas, and the absence of branches of the superior mesenteric artery (Fig. 1a, b). The small intestine and freely mobile jejunal end were supplied by a marginal artery (Fig. 1c). The type IV multiple jejunal atresia comprised three areas of type II atresia, the blind ends of which were separated by a fibrous cord 6, 8, and 11 cm from the jejunal end, respectively; and two areas of type I (mucosal) atresia with an intact bowel wall and mesentery 27 and 30 cm from the jejunal end, respectively (Fig. 1d). The biliary and pancreatic ducts were inserted into the duodenum proximal to the annular pancreas. The patient underwent resection from the jejunal end to 30 cm from the jejunal end, including all areas affected by jejunal atresia; side-to-end duodenojejunostomy; appendectomy; and replacement of the intestine in the peritoneal cavity. Reconstruction of the mesentery was easily performed because both margins of the mesentery were close in proximity to each other after the side-to-end duodenojejunostomy. The specimen (almost 10 cm from the jejunal end) showed >10 intestinal villi/mm, some goblet cells in each villus, and no Peyer's patches. These findings suggest that the specimen was jejunum. The postoperative course was uneventful. She was diagnosed with Down syndrome by chromosomal testing. The duodenum has an abundant dual vascular supply originating from the celiac axis and superior mesenteric artery. These vessels form the pancreaticoduodenal arcade, an important collateral between the celiac artery and the superior mesenteric artery. Some authors have suggested that the vascular accidents involving the pancreaticoduodenal arcade might have been the underlying cause of the duodenal atresia (Weber and Freeman 1999). Furthermore, some authors have suggested that Down syndrome cell adhesion molecule (DSCAM), located at 21q22.2, is associated with gastrointestinal problems, although it is evident that no single critical region of genes is sufficient to cause all Down syndrome phenotypes (Asim et al. 2015). We consider that the pathogenesis of the present case, especially the necrosis and defectiveness of the third and fourth parts of duodenum and proximal jejunum by strong ischemia in the SMA perfusion area as well as the presence of multiple jejunal atresia, was caused not only by vascular accidents of the pancreaticoduodenal arcade but also by failure of recanalization. Chromosomal disorders may lie behind these processes. None.