High Rate of Islets Autoimmunity in Pediatric Patients with Index Admission of Acute Pancreatitis

Introduction. The underlying pathophysiology of diabetes mellitus after acute pancreatitis is unknown and overall risk of developing diabetes postacute pancreatitis in children is understudied. The objective of our study was to describe the frequency of islet cell autoimmunity and abnormal glucose testing in pediatric patients in the year following their index case of acute pancreatitis. Materials and Methods. Data were obtained from a single-center observational cohort study of patients with their first episode of acute pancreatitis. Islet cell autoantibody titers were measured on stored plasma collected from acute pancreatitis diagnosis, at 3 months and at 12 months postacute pancreatitis attack. Abnormal glucose testing was defined as the presence of prediabetes or diabetes, as defined by American Diabetes Association criteria. Results. Eighty-four patients with acute pancreatitis and islet cell autoantibody data were included, 71 had available glucose measures. Median age at first acute pancreatitis attack was 14 years (IQR 8.7–16.3) and 45/84 (54%) were females. Twenty-four patients (29%) were positive for at least one of four islet cell autoantibodies (IAA, GADA, IA-2A, and ZnT8A) and 6 (7%) had two or more positive islet cell autoantibodies. Nineteen patients out of 71 (27%) had abnormal glucose testing at or postacute pancreatitis diagnosis. A higher proportion (37%, 7/19) with abnormal glucose testing had severe acute pancreatitis compared to those with normal glucose testing (13%, 7/52) ( $p=0.04$ ). Patients with normal glucose testing were more likely to be positive for one or more islet cell autoantibodies (31%, 16/52) compared to those with abnormal glucose testing (0%, 0/19) ( $p=0.004$ ). Conclusions. Islet cell autoimmunity is more common in children after their index acute pancreatitis attack (29%) than in the general population (7%–8%). While the frequency of prediabetes and diabetes postacute pancreatitis is high, other mechanisms besides islet cell autoimmunity are responsible.