[Microcolon in newborns: clinical significance and differential diagnosis].

Microcolon is a radiological finding of a colon of tiny caliber on barium enema examination. There are no absolute standards for measurement of this condition which is probably caused in utero by lack of appropriate distention of the colon with intramural content. A review was undertaken of 228 barium enema examinations of newborns admitted to Mackay Memorial hospital from January 1987 to December 1988. Twenty cases (8.7%) were regarded by the same radiologist as microcolon. Among them, ileal atresia was found in nine cases (45%); colonic atresia in two cases (10%); total colon agangliosis in three cases (15%); prenatal volvulus in two cases (10%); meconium ileus in two cases (10%); duplication of ileum in one case (5%): and megacystis-microcolon-intestinal hypoperistasis (MMIHS) in one case (5%). The characteristic features of plain abdomen and barium enema study were discussed. The finding of a microcolon on contrast enema study in newborn with lower gastrointestinal obstruction signifies that it may rise from lower gastrointestinal obstruction above colon, external compression, or motility disorder of the intestine itself. The outcome of microcolon seems to depend on its underlying causes. In those caused by obstruction, only the caliber may return to normal within days after removal of the obstruction.