False diagnosis of intestinal obstruction in a fetus with congenital chloride diarrhea.

Intestinal obstruction is often diagnosed prenatally by ultrasound, providing an opportunity for prenatal counseling, genetic investigation, and planned delivery at a perinatal center. We describe a patient with typical features of fetal bowel obstruction, who was found at birth to have congenital chloride diarrhea. A 25-year-old white woman had marked polyhydramnios; multiple dilated, fluid-filled loops of intestine were seen in the fetal abdomen on prenatal ultrasound. However, postnatally, there was no evidence of bowel obstruction. The infant girl passed large amounts of watery stools, but tolerated feeds well. A rectal biopsy showed normal ganglion cells. On the fourth day of life her serum sodium and chloride were markedly decreased, and stool chloride levels were diagnostic of congenital chloride diarrhea. She was placed on sodium chloride and potassium chloride supplements, and her serum electrolytes normalized. Congenital chloride diarrhea is a rare, inherited condition caused by an abnormality of intestinal electrolyte transport. This case illustrates that it may present prenatally with a picture similar to that seen with intestinal obstruction.