Abstract
Congenital diarrhea and enteropathies (CoDEs) condition is a rare cause of chronic diarrhea in infants that can be challenging to diagnose. This article discusses key signs to recognize in considering a CoDEs diagnosis and provides an overview of the diagnostic process. We report a late preterm twin infant with intractable watery diarrhea starting shortly after birth. The infant was born from a twin pregnancy to non-consanguineous parents with an unremarkable family history. His twin brother had no complications after birth and continued to thrive. The patient initially presented with bloody stools, leading to a suspected diagnosis of necrotizing enterocolitis or cow's milk protein-induced allergic colitis. However, the emergence of profuse and watery diarrhea, failure to thrive, and hypernatremic dehydration shifted the suspicion toward malabsorptive diarrhea. An extensive workup was significant for hypernatremic metabolic acidosis and positive stool-reducing substances. Several trials of protein-hydrolysate and elemental amino acid-based formulas failed to improve symptoms. However, stool consistency improved with a trial of a carbohydrate-free, hydrolyzed protein-based formula (3232A). As a diagnostic test for specific carbohydrate malabsorption, the infant was challenged with glucose supplementation followed by fructose supplementation; his stool consistency worsened with the glucose challenge but improved with the fructose challenge. His stool pH and reducing substances were abnormal after the glucose challenge and normalized after the fructose challenge, thus indicating a clinical diagnosis of glucose-galactose malabsorption (GGM). At the time of discharge, the infant had documented weight gain and formed stools on carbohydrate-free, hydrolyzed protein-based formula (3232A) supplemented with fructose. At one-year follow-up after discharge, he continued to thrive with normal bowel movements. Outpatient genetic testing confirmed our diagnosis of GGM. GGM should be considered in infants with severe protracted, non-infectious, watery diarrhea lasting longer than two weeks. Early diagnosis and management of infants with GGM with a carbohydrate-free formula with specific carbohydrate supplementation are essential to prevent complications and ensure optimal growth and development.