Introduction: Hybrid diabetes is a challenging form od diabetes that need to be more studied. We describe a case of hybrid diabetes with a prolonged honeymoon due to the use of metformin.
Case: Our patient is a 10 year old female patient who was diagnosed as type 2 DM on September 2017 at the age of 8 years. She was obese with BMI = 29.8 Kg/ m^2 with marked acanthosis nigricans. She had a patch of vitiligo on the face. Other systemic examination was unremarkable. Both grandparents had type 2 DM on oral treatment. The initial HbA1c was 8.7%. She was started on insulin basal and bolus with metformin along with behavioral and dietary modifications.
In few weeks, the insulin was stopped completely after a period of titration of the dose due to multiple episodes of hypoglycemia.
2 months later her BMI dropped to 24.5kg/m^2. On metformin 500 mg BID,her A1C dropped to 6.2%. workup showed: fasting insulin level of 45 pmol/l, HOMA-IR was 1.4,positive autoantibodies were detected including anti islet cell antibodies, anti ZnT8 Ab and anti-GAD 65 antibodies . Thyroid profile and celiac screen were all normal. At this point she was counseled about the possibility of honey moon associated with type 1 diabetes and kept on flash continuous glucose monitor to observe her glycaemia. 8 months later; her A1C= 5.7%
One year after diagnosis, her A1C started to increase again (7.1%), her BMI was 22.5kg/m^2. Metformin was increased to 1500mg daily.
When followed again 15 months after diagnosis, the A1C was still increasing to 7.9%, c-peptide was 1.8ng/ml, RBS 10mmol/l. At this stage, she was started on a small dose of glargine insulin (0.12 unit/kg/day)
On subsequent follow up (17 months after diagnosis) she showed evidence of increased insulin demand to 0.2 unit/kg/day of basal insulin with HbA1c od 7.9% and her BMI = 20.5kg/m^2 . Her mother attributed the worsening control to bad dietary habits. The diabetes etiology for her was challenged again especially after the subsequent visit that showed increasing A1C to 8.4%. At this point of her follow up, she was put back to basal bolus regimen.
Discussion & Conclusion: The role of metformin has been described as an adjunctive therapy in overweight young people with T1D. In this case it proved to be effective in hybrid diabetes with prolongation of the period without insulin therapy.
19 - 21 Sep 2019
European Society for Paediatric Endocrinology