Endocrine Abstracts

Background: Type 1 diabetes (T1D) is a metabolic disease of unknown aetiology that results from the autoimmune destruction of the insulin-producing pancreatic β-cells. Exogenous insulin administration is the only treatment for patients. Partial remission or “honeymoon phase” classically occurs a few weeks after insulin therapy has been initiated. During this stage the patient’s need for exogenous insulin can decline by 50%, and near-normal metabolic control is maintained. In a few cases, even temporary insulin independence can be achieved. Several clinical and metabolic factors have been found to influence the frequency and duration of the remission period, which depends partly on the recovery of β-cell function. The duration of this stage can vary from weeks to years. This stage of partial remission has generated much interest for the application of future therapies.

Case Report: 14 year old female presented November 2022 with 6 week history; polyuria, polydipsia and weight loss. Initial presentation consistent with diabetes not in DKA. Blood glucose 23.4 mmol/l, Ketones 0.5 mmol/l. pH 7.4 on admission blood gas. Investigations; Pancreatic Islet Cell Antibodies - weak positive, Anti-GAD Antibodies - 23.4 U/ml (positive>25U/ml), IgG Insulin Antibodies - 2.8 (0.0-5.0), HbA1c - 121 mmol/mol (<48 mmol/mol), ZnT8 sample lost in transit. Commenced on SC insulin 1unit/kg/day combination novorapid and lantus. Achieved good glycaemic control and was followed up in clinic. Subsequently commenced on continuous insulin pump with excellent control. Further admission May 2022. History of deliberate weight loss (91-98th percentile to 50-75th) restrictive diet (100kcal/day) and recurrent hypoglycaemic episodes. During admission insulin cautiously weaned to zero. Post mixed meal identified presence of urinary C-peptide indicating exogenous insulin production. Patient has been off insulin since May 2022. Repeat autoimmune workup awaited. Ongoing Libra monitor - flat-line with occasional peak >10 mmol. 90% in range.

Discussion: Is this a correct diagnosis of T1D? Unaware of antibody status. Could this be a case of prolonged honeymoon period secondary to deliberate weight loss? Could this be sustained honeymoon phase or even total remission? How could we monitor biomarkers in this phase that correlate with β-cell regeneration and immunotolerance induction? Can we predict; short term remission, intermediate remission or long term remission?