Performance of modified Igls criteria to evaluate islet autograft function after total pancreatectomy with islet autotransplantation – a retrospective study

BACKGROUND: The Igls criteria assess islet function after islet allotransplant, based on C-peptide, insulin use, hemoglobin A1c, and severe hypoglycemia. However, these criteria as currently defined cannot be applied to total pancreatectomy islet autotransplant (TPIAT) patients. METHODS: We tested modified criteria for assessing islet function in a large cohort TPIAT patients (n=379). Metabolic outcomes were assessed. We assigned Auto-Igls class to each patient as able and evaluated the utility, validity, and perioperative risk factors of Auto-Igls at 1 year post-IAT. We tested the association of Auto-Igls with independent measures of islet graft function, specifically continuous glucose monitoring (CGM) data or acute C-peptide response to glucose (ACRglu) from intravenous glucose tolerance tests. RESULTS: An Auto-Igls class was assigned to 264 patients (69%). Among patients who could not be classified, most were missing exact insulin dose. Seventy-three percent of TPIAT recipients were classified as optimal or good at 1 year. The only significant predictor of Auto-Igls class was islet mass transplanted (p