A low-fat amino acid diet reverses intestinal failure and shows good growth trends in five infants with diacylglycerol transferase 1 (DGAT1) deficiency: a prospective cohort study.

Background: Congenital diarrheas and enteropathies (CODEs) caused by diacylglycerol transferase 1 (DGAT1) mutations often cause disease within 2 weeks after birth. If not treated properly, the disease can be life-threatening; therefore, early diagnosis and rational treatment strategies are essential. This study was conducted to improve the understanding of congenital diarrhea caused by DGAT1 deficiency.

Methods: Clinical data from five congenital diarrhea infant cases caused by DGAT1 deficiency were analyzed. Infants were prospectively provided with a nutritional intervention with a low-fat amino acid formula for special medical purposes (FSMP). Their gastrointestinal symptoms and nutritional complications before and after interventions were compared.

Results: Due to poor weight gain and gastrointestinal symptoms after birth, infants were treated by our clinical nutritionist. Genetic testing confirmed a compound heterozygous mutation in DGAT1. Neither hydrolyzed nor high-medium chain triglyceride (MCT) formula significantly alleviated diarrheal symptoms; however, a low-fat amino acid diet rapidly relieved symptoms and significantly improved nutritional status, with infants showing better tolerance to dietary fat content with age.

Conclusions: Infants with DGAT1 deficiency can be diagnosed by genetic testing. A low-fat amino acid FSMP formula and diet can quickly relieve diarrhea, vomiting, and other symptoms, and also improve infant growth and development.

Trial registration: Ethical approval was obtained from the Medical Ethics Committee of the Children's Hospital of Fudan University (reference code: No.(2022)405).