A girl with permanent neonatal diabetes due to KCNJ11 mutation presented with Mauriac syndrome after improper adjustment in sulfonylurea dosage over 6 years.

Mauriac syndrome is characterized by growth impairment, Cushingoid features, and hepatomegaly in patients with poorly controlled type 1 diabetes mellitus (T1DM). We report a novel presentation of Mauriac syndrome in a 9-year-old girl who was diagnosed with neonatal diabetes at 3 months of age due to the p.R201C mutation in KCNJ11. She was initially treated successfully with glipizide at a dose of 0.85 mg/kg/day but after being lost to follow-up and having improper adjustment in dose over many years, the recent dose of 0.6 mg/kg/day appears to have been insufficient for glycemic control but enough to maintain a low level of C-peptide and prevent diabetic ketoacidosis. With proper insulin administration, all presenting clinical characteristics were resolved within 1 month. A review of the literature relating to clinical manifestations of Mauriac syndrome in children with diabetes was performed and included in this report for comparison with our patient. While Mauriac syndrome has been traditionally associated with T1DM, the presence of Mauriac syndrome should not be excluded in other types of diabetes mellitus.