Autoimmunity May Explain Diabetes in a Subset of Patients With Recurrent Acute and Chronic Pancreatitis: A Pilot Study

Risk and factors determining diabetes after mild, nonnecrotizing acute pancreatitis

PURPOSE OF REVIEW

Diabetes mellitus (DM) is relatively common following acute pancreatitis (AP), even after mild acute pancreatitis (MAP), the most frequent AP presentation, in which there is no overt beta cell injury. Post-AP related diabetes is widely misdiagnosed, resulting in potentially inappropriate treatment and worse outcomes than type 2 diabetes (T2D). Thus, it is important to understand risk across the spectrum of AP severity.

RECENT FINDINGS

Biological mechanisms are unclear and may include local and systemic inflammation leading to beta cell dysfunction and insulin resistance, altered gut barrier and/or gut peptides and possibly islet autoimmunity, though no studies have specifically focused on MAP. While studies examining clinical risk factors on MAP exclusively are lacking, there are studies which include MAP. These studies vary in scientific rigor, approaches to rule out preexisting diabetes, variable AP severity, diagnostic testing methods, and duration of follow-up. Overall, disease related factors, including AP severity, as well as established T2D risk factors are reported to contribute to the risk for DM following AP.

SUMMARY

Though numerous studies have explored risk factors for DM after AP, few studies specifically focused on MAP, highlighting a key knowledge gap that is relevant to the majority of patients with AP.

Differences in glucose homeostasis and islet injury among diverse mice strains post acute pancreatitis

Diverse animal models have been used to study postpancreatitis diabetes mellitus (PPDM) development; however, no study has yet conducted a comparative analysis of the specific differences in glucose homeostasis and islet injury between these models. Therefore, we investigated the differences in pancreatic islet injury and glucose homeostasis among diverse strains in a cerulein-induced acute pancreatitis (AP) model to determine the appropriate animal model for PPDM. BALB/cJ, C57BL/6J, C57BL/6 N, and FVB/NJ mice were administered cerulein to induce AP. Serum amylase levels, pancreatic acinar injury, blood glucose homeostasis, islet function, and islet injury were measured and analyzed. All strains exhibited elevated amylase secretion post pancreatitis, and BALB/cJ, C57BL/6J, and C57BL/6 N mice exhibited sex-related differences. All strains exhibited pancreatic acinar injury post pancreatitis but mostly recovered within 15 days. Overall, glucose homeostasis remained balanced post pancreatitis in all strains compared to that in the control groups, except in FVB/NJ male and female mice, which exhibited an imbalance in glucose homeostasis on day 7 post pancreatitis. All the strains, except BALB/cJ mice, exhibited a decline in Homeostasis model assessment-β(HOMA-β) values post pancreatitis, with significant decrease in C57BL/6J females and FVB/NJ males. Islet size decreased post pancreatitis in all strains, except BALB/cJ mice. Pancreatic islet insulin secretion levels significantly decreased in male FVB/NJ mice post pancreatitis onset and did not recover within 15 days. Therefore, FVB/NJ male mice are a useful model for studying PPDM.

The spectrum of diabetes in acute and chronic pancreatitis

PURPOSE OF REVIEW

To discuss the spectrum of diabetes related to acute and chronic pancreatitis (which are types of pancreatogenic diabetes) and its overlapping features with type 1 and type 2 diabetes.

RECENT FINDINGS

Patients with diabetes related to acute and chronic pancreatitis present clinically within a spectrum of overlapping features with other forms of diabetes. In this spectrum, glucose metabolism alterations range from increased insulin resistance following acute pancreatitis (resembling type 2 diabetes) towards a permanent loss of beta-cell function and impaired insulin secretion in end-stage chronic pancreatitis. Overlapping features with type 1 diabetes (beta cell autoantibodies) and type 2 diabetes (obesity, dyslipidemia, and hereditary/genetic factors) contribute to the heterogeneity of this spectrum.

SUMMARY

Pancreatogenic diabetes secondary to acute or chronic pancreatitis is a heterogeneous entity with a variable clinical presentation, including many cases that are misdiagnosed and treated as type 2 diabetes. This is problematic as pancreatogenic diabetes is associated with a poor prognosis and entails special considerations for management. Recent discoveries showing overlapping features with type 1 and type 2 diabetes along with an improved understanding of its pathophysiology are expected to improve the diagnosis and treatment of these and other forms of pancreatogenic diabetes.

Pancreatogenic Diabetes in Children With Recurrent Acute and Chronic Pancreatitis: Risks, Screening, and Treatment (Mini-Review)

Up to 9% of children with acute recurrent pancreatitis (ARP) or chronic pancreatitis have pancreatogenic diabetes mellitus (DM), and this risk likely increases as they age into adulthood. Risk factors for pancreatogenic DM in children vary depending on the clinical cohort but may include pancreatic atrophy, exocrine insufficiency, pancreatic calcifications, obesity/metabolic syndrome features, or autoimmune diseases. Knowledge regarding disease pathology is extrapolated nearly entirely from studies in adults. Insulin deficiency is the primary defect, resulting from islet loss associated with pancreatic fibrosis and cytokine-mediated β-cell dysfunction. Beta cell autoimmunity (type 1 diabetes) should also be considered as markers for this have been identified in a small subset of children with pancreatogenic DM. Hepatic insulin resistance, a deficient pancreatic polypeptide state, and dysfunctional incretin hormone response to a meal are all potential contributors in adults with pancreatogenic DM but their significance in pediatrics is yet unknown. Current guidelines recommend yearly screening for diabetes with fasting glucose and hemoglobin A1c (HbA1c). Insulin in the first-line pharmacologic therapy for treatment of pancreatogenic DM in children. Involvement of a multidisciplinary team including a pediatric endocrinologist, gastroenterologist, and dietitian are important, and nutritional health and exocrine insufficiency must also be addressed for optimal DM management.