Continuous glucose monitoring (CGM) systems reduce self-monitoring burden compared with glucose meter use but have limitations when used after total pancreatectomy with islet autotransplantation (TPIAT). An example is false elevation of sensor readings after hydroxyurea (HU) administration, a medication often used after TPIAT. This study compared user experiences of CGM not affected by HU with CGM affected by HU in pediatric patients post-TPIAT.
This was a retrospective study of 20 TPIAT patients. Caregivers were informed of known limitations and chose the CGM system for postoperative use. Ten chose a Dexcom, and 10 chose a FreeStyle Libre CGM system. Demographic data and caregiver-reported CGM concerns were collected up to 16 weeks after discharge.
Half of Dexcom users reported false hypoglycemia alerts that resolved with repositioning, recalibration, or sensor change. False hyperglycemia was an anticipated outcome and therefore not reported as concerning. Eight FreeStyle Libre users reported false hypoglycemia and frequent alarms that persisted despite sensor changes, which limited device supply. These concerns could not be independently resolved, contributed to caregiver distress, and interrupted sleep. More FreeStyle Libre patients switched to Dexcom than Dexcom patients who switched to a FreeStyle Libre system (70 vs. 10%, P = 0.02) by a median of 2.9 weeks after discharge.
Caregivers reported frequent false alarms on both systems. The frequency of false hypoglycemia with FreeStyle Libre was an unexpected limitation with an unclear cause. The inability to calibrate the FreeStyle Libre likely contributed to frequent sensor changes and supply depletion. The ability to recalibrate the Dexcom system may provide an advantage, but not for people taking HU. Knowledge of CGM limitations post-TPIAT can help individuals make informed decisions.