Microcolon in Neonates: Clinical and Radiographic Appearance

Microcolon (unused colon) is not a common problem in neonates. Radiographic contrast medium enema shows a small caliber colon. This report concerns 12 neonates with microcolon, all identified between January 1995 and June 1997 by contrast medium colon study. Gestational ages were between 28 to 38 weeks and birth body weight between 1,400 to 3,100 grams. Six neonates had jejunal atresia (50%), three ileal atresia (25%), two total colonic aganglionosis (17%), and one meconium ileus (8%), all proven by surgery or intestinal biopsy. The plain film and contrast medium enema presented some characteristic features are described. The major clinical findings including bilious vomiting in jejunal atresia, abdominal distention mainly in distal ileal atresia, total colonic aganglionosis and meconium ileus. Eight neo-nates (67%) did not pass meconium. The outcome of microcolon depends on its underlying disease or congenital anomaly. (Clinical Neonatology 1998;5(1): 14-18) Key words: Microcolon, neonate A microcolon may be defined as a colon of abnormally small caliber. However, there is no absolute standard for this measurement. The finding of microcolon on contrast enema study in newborns with distended abdomen usu-ally suggests jejunoileal obstruction, jejunoileal atresia, meconium ileus, or occasionally total colonic agan-glionosis [1]. These conditions require immediate treat-ment, either surgically [2] or by hyperosmolar contrast enema [3,4]. We report on twelve neonates in which microcolon was detected because of bilious vomiting, abdominal distention and failure to pass meconium immediately after birth. All twelve neonates had contrast enema ex-aminations showing a total microcolon. The purpose of this article is to describe the clinical presentations with radiographic imaging, which are important for accurate pre-operative diagnosis