Novel DGAT1 Mutations Identified in Congenital Diarrheal Disorder 7: A Case Report with Therapeutic Experience

Congenital diarrheal disorders (CDD) are a group of rare inherited intestinal disorders, among which CDD7 was recently identified to be associated with only 24 mutations in gene coding for diacylglycerol-acyltransferase 1 (DGAT1). We report on a female patient who presented with diarrhea, vomiting, hypoalbuminemia, and failure to thrive after birth. Two novel variants of c.1215_1216delAG and c.838C>T were found in the DGAT1 gene by whole exome sequencing, which was confirmed to be compound heterozygous by Sanger sequencing. Her symptoms and nutritional status improved significantly after 1 year of a fat-restricted enteral diet. Weight for age and weight for length increased from -5.0 SDS and -4.0 SDS at 3 months to +0.08 SDS and +1.75 SDS at 15 months, respectively. This report expanded the mutation spectrum of DGAT1-related CDD7 and enriched our knowledge of the clinical features. Moreover, early fat-restricted enteral diet intervention was suggested for the treatment of such patients.