Post–COVID-19 autoimmune hypoglycemia: A case report

Abstract

ABSTRACT Insulin autoimmune hypoglycemia is characterized by insulin autoantibodies causing initially hyperglycemia followed by hypoglycemia. The authors describe a case of a patient who presented with recurrent episodes of severe hypoglycemia 1 month after COVID-19 infection. Blood glucose monitoring during admission revealed postprandial hyperglycemia ranging from 15 to 18 mmol/L followed by severe hypoglycemic episodes. His insulin at the time of hypoglycemia (blood glucose level 1.5 mmol/L) was 255 mU/L (3–25 mU/L). C-peptide was 3.3 nmol/L (0.3–1.4 nmol/L), and β-hydroxybutyric acid was 0.06 mmol/L (<0.27 mmol/L). The anti-insulin antibodies level elevated at 403 U/mL (<0.5 U/mL). A diagnosis of post–COVID-19 autoimmune hypoglycemia was performed, and the patient was started on high-dose prednisolone 60 mg/day with gradual tapering over 3 months. Metformin and acarbose were also started to treat hyperglycemia. On follow-up after glucocorticoid cessation, blood glucose profile stabilized with no hypoglycemia or hyperglycemia. This is the fourth case report written in the literature.