Misdiagnosis of congenital chloride-losing diarrhea.

Congenital chloride-losing diarrhea is a recessively inherited disorder due to the absence of chloride-bicarbonate exchange in the small bowel. Malabsorption of chloride leads to osmotic diarrhea, electrolyte abnormalities, and dehydration. If left untreated, the infants fail to thrive and have a very high mortality. Clinically, affected patients develop secretory diarrhea in utero resulting in distended bowel loops and polyhydramnios. At birth these infants have profuse watery diarrhea that may be confused with urine. Thus, the correct diagnosis is often missed, and they may be subjected to unnecessary interventions. If diagnosed early, the electrolyte abnormalities are easily corrected and the prognosis is good. We report two patients who were initially evaluated for other conditions but later proved to have congenital chloride-losing diarrhea. The cases emphasize the importance of having a high index of suspicion in patients with a history of polyhydramnios, prematurity, and watery stools.