BACKGROUND: Congenital chloride diarrhea (CCD) is a rare autosomal recessive disorder that is difficult to distinguish from fetal lower intestinal obstruction. A prenatal diagnosis will make a contribution to the prognosis of the newborn.

CASE REPORT: We report a rare case of congenital chloride diarrhea (CCD) prenatally suspected by ultrasound and MRI. The prenatal ultrasound revealed signs of intestinal dilatation suggesting lower intestinal obstruction. MRI findings also revealed intestinal dilatation that continued from the rectum. On T1-weighted images, fluid accumulation within the bowel was hypointense. CCD was strongly suspected rather than obstruction of the lower intestinal tract or Hirschsprung’s disease. At 37 weeks and 3 days’ gestation, cesarean section was performed because of fetal distress. The newborn was a 2396 g male with the Apgar scores 8 (1 min) and 9 (5 min). Watery diarrhea subsequently persisted, and on the 3rd day, hyponatremia and hypochloremia were present. The infant stool was hyperchloremic, so we diagnosed CCD.

CONCLUSIONS: When ultrasonography reveals signs of fetal gastrointestinal dilatation, lower intestinal obstruction is considered first. CCD is infrequent and has signs of intestinal dilatation similar to those of other intestinal ailments, so distinguishing these conditions is difficult. However, if CCD is suspected early, then use of MRI will allow its diagnosis. If the condition is diagnosed before birth, the prognosis of the newborn will improve.

Keywords: Diarrhea, Infantile, Intestinal Obstruction, Polyhydramnios