Clinical Characteristics and Genetic Causes of Infantile Exocrine Pancreatic Insufficiency in Chinese Patients: Study From a Tertiary Care Center.

OBJECTIVE: Infantile exocrine pancreatic insufficiency is a rare disease. We examined phenotypes and performed genetic sequencing in children with this disorder.

METHODS: We enrolled 4 infants with exocrine pancreatic insufficiency. Patients were characterized by phenotypes and radiologic findings. Genetic sequencing was performed.

RESULTS: Average age of disease onset was 2 months. Average (standard deviation [SD]) age at diagnosis was 11.9 (7.0) months. Patients presented with chronic steatorrhea and failure to thrive. Two had mild zinc deficiency. Imaging showed pancreatic lipomatosis and metaphyseal dysplasia among all patients. For these patients with similar phenotypes, genetic sequencing revealed that 2 patients had novel UBR1 mutations (c.[3043_3046delAAAG; c.3848 + 6T > C] and c.[1850-2A > T;c.4290T > G], reference sequence NM_174916), and another 2 patients had homozygous SBDS c.258 + 2T > C mutation and SBDS c.[258 + 2T > C;c.428C > T] mutations (reference sequence NM_016038.2). All patients received pancreatic enzyme replacement therapy.

CONCLUSIONS: Here we described 4 patients with infantile exocrine pancreatic insufficiency confirmed by laboratory tests and imaging. Whole-exome sequencing and Sanger sequencing showed that 2 patients had Johanson-Blizzard syndrome and 2 patients had Shwachman-Diamond syndrome. Genetic sequencing should be applied for definite diagnosis among these patients.