SUN-543 Development of Beta-cell Autoimmunity and Type 1 Diabetes Mellitus in an Elderly Patient Following SARS-CoV-2 Infection

Abstract Disclosure: E.B. Layadi: None. B.A. Ilmaguook: None. I. Khan: None. M. Michal: None. D. George: None. A. Khan: None. G. Rodriguez: None. G. Bahtiyar: None. S. Kuperberg: None. Background: The prevalence rate of type 1 diabetes mellitus (T1DM) has increased exponentially for the last 20 years, even in the elderly. T1DM particularly in elderly population poses a diagnostic challenge as it shares overlapping clinical features with T2DM, which could lead to misdiagnosis. History of COVID-19 could be overlooked as one of the predisposing factors of developing new-onset autoimmunity, even though there are growing body of evidence which have linked SARS-CoV-2 infection to the development of islet autoantibodies. Here we report a case of an elderly female with history of COVID-19 infection 8 months prior to presentation, which was followed by conversion of autoantibodies to positive results and worsening glycemic control. Case presentation: A 77-year-old female with a history of Hashimoto’s hypothyroidism, prediabetes, and autoimmune atrophic gastritis (AAP) who presented to the hospital with worsening acute diffuse abdominal pain. She was vitally stable and was noted with pH 7.29, bicarbonate 14 (24-31 mmol/L), AG 29 (5-15), BHB >4.5 (0.02-0.27 mmol/L) indicative of moderate DKA. C-peptide was noted at 0.8 (ref 1.1-4.4 ng/ml), most recent HbA1C 7 months prior to hospitalization was 6.2% and the repeat while admitted was 14.7% (ref 4-5.6%). Glutamic acid decarboxylase autoantibody (GADA) was noted to be positive with level of 50.6 (high, n ≤0.02 nmol/L). Subsequent workups obtained, noted with high titers of Islet Cell Antibody (ICA) 1:128 (normal value <1:4), high Islet Antigen 2 (IA-2) antibody 9.45 (n≤0.02 nmol/L), high Zinc Transporter 8 (ZnT8) antibody 280 U/ml (n<15 U/mL). Previous records obtained and salient lab results were remarkable for negative Islet cell antibody (<5 units/mL) 9 years prior to hospitalization. The patient was initiated on isotonic fluid, insulin drip 3-11 units/hour and close electrolyte monitoring. Closure of anion gap noted on two repeats with treatment indicating resolution DKA. The hospital course was also complicated with acute saddle pulmonary embolism confirmed from CT angiogram of the chest. The patient was discharged on basal bolus insulin regimen. Conclusion: Although uncommon, SARS-CoV-2 infection has been associated with the development of beta-cell autoimmunity, which could be illustrated in this case. Recognizing history of COVID-19 as one of the predisposing factors could elevate the degree of suspicion for T1DM, which could lead to a timely diagnosis. Ultimately, the complexity in the diagnosis and management of T1DM in elderly population poses a need for further research. Presentation: Sunday, July 13, 2025