MODY3 and liver adenoma in pregnancy: a case report supporting routine liver ultrasound screening

Maturity-onset diabetes of the young (MODY) is characterised by monogenic, autosomal dominant inheritance. HNF1A-MODY (formerly MODY3) is the most common because of a mutation of hepatocyte nuclear factor 1A (HNF1A). HNF1A is a tumour suppressor gene, and bi-allelic mutations are associated with hepatocellular adenomas (HCAs), liver adenomatosis and liver malignancies. HNF1A-inactivated HCAs are usually sporadic, but one-third have a germline mutation and an underlying diagnosis, such as HNF1A-MODY. Haddouche et al. evaluated 137 patients with HNF1A-MODY; 6.5% were diagnosed with liver adenomatosis and 25% were diagnosed because of haemorrhagic complications. The increasing recognition of HCA and adenomatosis in HNF1A-MODY has led to recommendations for routine screening.