Predicting islet yield in pediatric patients undergoing pancreatectomy and autoislet transplantation for chronic pancreatitis.

BACKGROUND/
OBJECTIVE: Chronic pancreatitis (CP) in children is associated with significant morbidity and can lead to narcotic dependence. Total pancreatectomy (TP) may be indicated in refractory CP to relieve pain; simultaneous islet autotransplant (IAT) may prevent postsurgical diabetes. About half of pediatric patients are insulin independent 1 yr after IAT. Insulin independence correlates best with the number of islets available for transplantation (islet yield). Currently there is no known method to predict islet yield in a given patient. We assessed the ability of preoperative metabolic tests to predict islet yields in 10 children undergoing TP/IAT. DESIGN/
METHODS: Hemoglobin A1c (HbA(1c)) and mixed meal tolerance tests (MMTT) were obtained prior to surgery in 10 patients age <or= 18 yr. Fasting glucose, C-peptide, and creatinine were used to calculate the C-peptide to glucose* creatinine ratio (CPGCR). C-peptide peak and area under the curve (AUC) were determined from 2 h MMTT. Linear regressions were performed to predict islet yield from baseline test results.
RESULTS: Islet yield ranged from 7000 to 434 000 islet equivalents (IE) (mean 222 452 +/- 148 697 IE). Islet yield was well predicted from body weight and fasting plasma glucose (R (2) = 57%, adjusted for overfitting by bootstrap). Islet yield was positively associated with CPGCR, peak C-peptide, and AUC C-peptide and negatively associated with HbA(1c).
CONCLUSIONS: Pilot data from 10 pediatric patients suggest that simple preoperative measurement of fasting plasma glucose may give a useful prediction of islet yield. Islet yield correlates with HbA(1c) and C-peptide levels. This information allows individual candidates to weigh the specific risk of becoming diabetic against the benefit of pain relief should they undergo TP-IAT.