Glycemic Profile of Intravenous Dexamethasone-Induced Hyperglycemia Using Continuous Glucose Monitoring

BACKGROUND Intravenous (IV) dexamethasone is widely used in critical illness, chemotherapy, or severe COVID-19. Although glucocorticoid-induced hyperglycemia (GCIH) is well-known, there is no report describing the glycemic profile following a single dose of IV dexamethasone as captured on continuous glucose monitoring (CGM) in a patient with diabetes treated with insulin. CASE REPORT A 70-year-old woman with diabetes and pancreatic adenocarcinoma was treated with chemotherapy containing dexamethasone every other week. CGM data of 23 cycles revealed a reproducible triphasic glycemic pattern consisting of a constant hyperglycemia period, followed by a transient improvement, and ending with another hyperglycemic plateau. Given this recurrent pattern, basal insulin and correction insulin were adjusted with subsequent GCIH attenuation. CONCLUSIONS This is the first report of CGM glycemic profile following recurring doses of IV dexamethasone in a patient with diabetes treated with basal-bolus insulin. The understanding of triphasic glycemic pattern allows optimal glycemic management.