Neonatal Diabetes due to a Mutation in the Distal PTF1A Enhancer: A Case Report and Literature Review

Biallelic variants in the pancreas-specific transcription factor 1A (PTF1A) gene are a rare cause of permanent neonatal diabetes. We report a case of neonatal diabetes with unique clinical manifestations. The clinical diagnosis of the affected infant was confirmed by insufficient endocrine and exocrine pancreas activity; however, the pancreas was normal in imaging. Molecular analyses identified a novel homozygous single nucleotide variant (Chr10, g.23508441T > G), affecting a highly conserved nucleotide within a distal enhancer of the PTF1A gene. The literature review showed that most of these patients had IUGR and imaging evidence of pancreatic agenesis or hypoplasia. We suggest that pancreatic imaging and evaluation of exocrine pancreas function can help early confirmation of the diagnosis in patients with permanent neonatal diabetes.