Submit Manuscript | http://medcraveonline.com infant developed progressive abdominal distention while under observation in the neonatal ICU. On examination, the infant looked generally well, maintaining on room air, vital signs were normal and no dismorphic features. Abdomen was distended all over, there was no visible peristalsis or visible bowel loops with normal overlying skin. It was soft and lax, with no palpable mass, but had exaggerated bowel sounds. Digital rectal examination revealed a normal anal orifice with normal muscle tone. Baby passed little sticky meconium after rectal stimulation, but no gush of gas or stool on withdrawal of finger. A preliminary clinical impression of meconium plug syndrome was made, and conservative treatment started including fleet enema, but unfortunately, the condition of the patient did not improve in spite of repeated enemas. Blood counts, Hemoglobin, serum chemistry, renal functions were within normal values. Liver function showed unconjugated hyperbilirubinemia, but other parameters were normal. Plain abdominal x ray revealed dilated bowel loops all over the abdomen, no air fluid levels, no free intraperitoneal gas, no intramural gas, and no evidence of any mass lesion. However it revealed diffuse gaseous distention of colon, more prominent on the left side. Gastrograffin contrast enema study was undertaken, for diagnostic as well as therapeutic purposes, due to suspicion of meconium plug syndrome. It revealed classic cone shaped narrowing in recto sigmoid area, with proximal dilatation of bowel and distal narrowing suggesting the presence of Hirschsprung's disease (Figure 1).The dye was retained in the bowel for more than 24 hours. Baby kept NPO and was put on TPN, frequent OGT aspiration. Baby was monitored continuously and prepared for surgery. Repeated x ray of the abdomen revealed an increase in bowel distention and appearance of air fluid levels. Exploratory laparotomy was performed on day six of life. Intraoperatively, we found dilated large colon, with transitional zone at rectosigmoid level, and distal collapsed bowel (Figure 2). Multiple full thickness biopsies were taken from the collapsed, dilated bowel loops as well as the transitional zone. The exploration of the rest of the bowel revealed the presence of a moderate sized mesenteric cyst in the mid ileum (Figure 3). The cyst was quite tense, thick walled, stretching the adjoining loop of ilium and causing partial intestinal obstruction. In view of these finding, a wedge resection of the cystic lesion along with the affected bowel loop was undertaken, and end to end anastomosis of the ileum was performed. A divided colostomy was performed just above the transition zone and the abdomen closed. AbstractHirschsprung's Disease is an uncommon cause of functional intestinal obstruction in neonates, especially females. Duplication of bowel is also a rare cause of mechanical obstruction in children at birth. An association of these two congenital anomalies is not reported in the available English language literat...