SAT-640 Glycemic Profile of Intravenous Glucocorticoid Induced Hyperglycemia Using Continuous Glucose Monitoring

Abstract

Background: Intravenous (IV) steroids are widely used in critically ill patients and with chemotherapy. It is well known that glucocorticoid-induced hyperglycemia (GCIH) occurs within 3 hours following oral administration of steroids with typical postprandial glycemic excursions lasting 24-36 hours. The recent increased availability of Continuous Glucose Monitoring (CGM) has allowed a detailed description of glycemic fluctuations in patients receiving steroids in different settings, however there is no reported observation of CGM findings following a single dose of IV Dexamethasone in a patient with diabetes. We present a case of glycemic pattern documented on CGM of a patient with type 2 diabetes, who had received 11 cycles of a single dose Dexamethasone-containing chemotherapy. Clinical Case: The patent is 70 years old female with history of type 2 DM of 19 years duration and metastatic pancreatic adenocarcinoma, diagnosed in November 2018, and treated with Fluorouracil and Dexamethasone 6mg IV on every other Wednesday since December 2018. Her diabetes was fairly controlled on Metformin, Repaglinide, Pioglitazone and Detemir insulin. Premeal Lispro was added while Metformin and Repaglinide were discontinued with the beginning of chemotherapy. She started using Freestyle Libre CGM in January 2019. During her visit in March 2019, the patient was taking Detemir Insulin 50 units in AM and 30 units at night, and Lispro 15 units before meals, in addition to correction insulin based on an Insulin Sensitivity Factor (ISF) of 1:25 for Blood Glucose (BG) above 200mg/dl. Unlike the reported postprandial hyperglycemic excursions associated with oral steroids, the patient’s CGM data showed a reproducible triphasic glycemic pattern following IV Dexamethasone, consisting of a steady state of hyperglycemia reached within 3 hours and lasting around 18-30 hours, followed by a transient BG improvement for 18-20 hours, and ending with another hyperglycemic plateau of 10-16 hours on day 3 post chemotherapy, with no association to meal intake. Given this recurrent pattern, the patient was advised to increase her bedtime Detemir insulin from 30 to 45 units and her correction ISF from 1:25 to 1:18 on days 1 and 2 after chemotherapy, with subsequent attenuation and shortening of GCIH. Conclusion: Our case report is the first one to describe CGM documented glycemic profile following a single dose of IV Dexamethasone in a patient with type 2 diabetes treated with insulin. The CGM data reveals a consistent steady GCIH, lasting around 48 hours, and reflecting the prolonged action of Dexamethasone. The transient BG improvement seen on day 2 is likely due to the Detemir dose self-increase and the carbohydrates intake decrease in response to day 1 hyperglycemia. A 48 hours modified insulin regimen based on higher dose of long acting and correction insulin improved Dexamethasone induced hyperglycemia.