Type la glycogen storage disease complicated with diabetes mellitus: the role of flash continuous glucose monitoring.

A 22-year-old woman with type Ia glycogen storage disease was referred to the endocrinology department with new-onset diabetes mellitus-glycated haemoglobin (HbA1c) of 8.2%. She had suffered from repeated bouts of hypoglycaemia since the first days of her life. The diagnosis was made at 5 months old, after clinical investigations revealed mixed dyslipidaemia, lactic acidosis and hepatomegaly. Compound heterozygosity was documented at the age of 4. The basis of her initial treatment was starch and reinforced soy milk, ingested multiple times a day and night. The patient suffered from obesity since childhood. This case shows a rare association between glycogen storage disease type Ia and diabetes mellitus. A multidisciplinary approach was implemented. Through diet and use of flash continuous glucose monitoring, we were able to improve patient's adherence and metabolic profile. Hypoglycaemia and hyperglycaemia risk significantly decreased; 86% time in range (70-180 mg/dL), 6% hypoglycaemia and 6.3% HbA1c in recent evaluations.