Unraveling the relationship between autoimmune pancreatitis type 2 and inflammatory bowel disease: Results from two centers and systematic review of the literature

Pancreas 2000. My journey with the central organ

The European Pancreatic Club Lifetime Achievement Award is a distinction awarded for research on the pancreas and service to European Pancreatology. It comes with the obligation to submit a review article to our society's journal, Pancreatology. It was awarded to me 2023 and I take this opportunity to highlight my journey with the central organ AKA the pancreas, that is inseparatable from "Pancreas 2000" - an educational program for future pancreatologists, inaugurated by Karolinska Institutet.

Can serum immunoglobulin G4 levels and age serve as reliable predictors of relapse in autoimmune pancreatitis?

We are writing in response to the paper published in the World Journal of Gastroenterology by Zhou et al. The authors identified higher serum immunoglobulin (Ig) G4 levels and age over 55 years as independent risk factors for disease relapse. Despite notable strengths, it is crucial to address potential biases. Firstly, the cohort study included 189 patients with autoimmune pancreatitis (AIP) type 1 (with higher IgG4 seropositivity and higher relapse) and 24 with type 2 (with lower IgG4 seropositivity and lower relapse). Consequently, most, if not all, AIP type 2 patients were assigned to the normal group, possibly inflating the association of higher serum IgG4 levels with relapse and potentially exaggerating the association of older age with relapse. Secondly, the authors did not provide sufficient details regarding AIP diagnosis, such as the ratio of definitive vs probable cases and the proportion of biopsies. In cases where histological evidence is unavailable or indeterminate, AIP type 2 may be misdiagnosed as definitive type 1, and type 1 may also be misdiagnosed as probable type 2, particularly in cases with normal or mildly elevated serum IgG4 levels. Lastly, in this retrospective study, approximately one-third of the consecutive patients initially collected were excluded for various reasons. Accordingly, the impact of non-random exclusion on relapse outcomes should be carefully considered. In conclusion, the paper by Zhou et al offers plausible, though not entirely compelling, evidence suggesting a predictive role of elevated serum IgG4 levels and advanced age in AIP relapse. The foundation for future investigations lies in ensuring a reliable diagnosis and accurate disease subtyping, heavily dependent on obtaining histological specimens. In this regard, endoscopic ultrasound-guided fine-needle biopsy emerges as a pivotal component of the diagnostic process, contributing to mitigating biases in future explorations of the disease.

Treatment approaches in autoimmune pancreatitis (Review)

Autoimmune pancreatitis (AIP) is a rare disease. There are two distinct types of AIP: AIP type 1 (AIP-1), a pancreatic manifestation of a multi-organ disease linked to immunoglobulin (Ig)G4, and AIP type 2 (AIP-2), a pancreas-specific disease unrelated to IgG4. The usual course of treatment for AIP is oral corticosteroid medication. Rituximab has also been recommended for recurrent AIP-1 in order to initiate remission and provide ongoing treatment. Immunomodulators such as azathioprine are used to keep certain patients in remission. Evaluation also takes into account a number of pharmacological alternatives, including biologic drugs like anti-tumor necrosis factor therapy, a safe and efficient second-line treatment for AIP-2 relapse or steroid dependence. Corticosteroids and immunosuppressants, which are poorly tolerated due to considerable side effects, are being replaced by other biologic drugs, which may offer a beneficial therapeutic alternative.

Risk factors for diabetes mellitus after acute pancreatitis: a systematic review and meta-analysis

Introduction

Within 5 years of having acute pancreatitis (AP), approximately 20% of patients develop diabetes mellitus (DM), which later increases to approximately 40%. Some studies suggest that the prevalence of prediabetes (PD) and/or DM can grow as high as 59% over time. However, information on risk factors is limited. We aimed to identify risk factors for developing PD or DM following AP.

Methods

We systematically searched three databases up to 4 September 2023 extracting direct, within-study comparisons of risk factors on the rate of new-onset PD and DM in AP patients. When PD and DM event rates could not be separated, we reported results for this composite outcome as PD/DM. Meta-analysis was performed using the random-effects model to calculate pooled odds ratios (OR) with 95% confidence intervals (CI).

Results

Of the 61 studies identified, 50 were included in the meta-analysis, covering 76,797 participants. The studies reported on 79 risk factors, and meta-analysis was feasible for 34 risk factor and outcome pairs. The odds of developing PD/DM was significantly higher after severe and moderately severe AP (OR: 4.32; CI: 1.76-10.60) than mild AP. Hypertriglyceridemic AP etiology (OR: 3.27; CI: 0.17-63.91) and pancreatic necrosis (OR: 5.53; CI: 1.59-19.21) were associated with a higher risk of developing PD/DM. Alcoholic AP etiology (OR: 1.82; CI: 1.09-3.04), organ failure (OR: 3.19; CI: 0.55-18.64), recurrent AP (OR: 1.89; CI: 0.95-3.77), obesity (OR: 1.85; CI: 1.43-2.38), chronic kidney disease (OR: 2.10; CI: 1.85-2.38), liver cirrhosis (OR: 2.48; CI: 0.18-34.25), and dyslipidemia (OR: 1.82; CI: 0.68-4.84) were associated with a higher risk of developing DM.

Discussion

Severe and moderately severe AP, alcoholic and hypertriglyceridemic etiologies, pancreatic necrosis, organ failure, recurrent acute pancreatitis and comorbidities of obesity, chronic kidney disease liver disease, and dyslipidemia are associated with a higher risk of developing PD or DM.

Systematic review registration

https://www.crd.york.ac.uk/prospero/, identifier CRD42021281983.

Autoimmune Pancreatitis in Patients with Inflammatory Bowel Disease: A Real-World Multicentre Collaborative ECCO CONFER Study

BACKGROUND

Autoimmune pancreatitis [AIP] is rarely associated with inflammatory bowel disease [IBD]. The long-term outcomes of AIP and IBD in patients with coexisting AIP-IBD and predictors of complicated AIP course have rarely been reported.

METHODS

An ECCO COllaborative Network For Exceptionally Rare case reports project [ECCO-CONFER] collected cases of AIP diagnosed in patients with IBD. Complicated AIP was defined as a composite of endocrine and/or exocrine pancreatic insufficiency, and/or pancreatic cancer. We explored factors associated with complicated AIP in IBD.

RESULTS

We included 96 patients [53% males, 79% ulcerative colitis, 72% type 2 AIP, age at AIP diagnosis 35 ± 16 years]. The majority of Crohn's disease [CD] cases [78%] had colonic/ileocolonic involvement. In 59%, IBD preceded AIP diagnosis, whereas 18% were diagnosed simultaneously. Advanced therapy to control IBD was used in 61% and 17% underwent IBD-related surgery. In total, 82% of patients were treated with steroids for AIP, the majority of whom [91%] responded to a single course of treatment. During a mean follow-up of 7 years, AIP complications occurred in 25/96 [26%] individuals. In a multivariate model, older age at AIP diagnosis was associated with a complicated AIP course (odds ratio [OR] = 1.05, p = 0.008), whereas family history of IBD [OR = 0.1, p = 0.03], and CD diagnosis [OR = 0.2, p = 0.04] decreased the risk of AIP complications. No IBD- or AIP-related deaths occurred.

CONCLUSIONS

In this large international cohort of patients with concomitant AIP-IBD, most patients have type 2 AIP and colonic IBD. AIP course is relatively benign and long-term outcomes are favourable, but one-quarter develop pancreatic complications. Age, familial history of IBD, and CD may predict uncomplicated AIP course.

Autoimmune pancreatitis type 2 (idiopathic duct-centric pancreatitis): A comprehensive review

Autoimmune pancreatitis (AIP) is an uncommon fibro-inflammatory disorder precipitated by autoimmune/inflammatory reactions. Currently, there are two clinical subtypes of AIP (type 1 [AIP-1] and type 2 [AIP-2]) that correspond to two histologic descriptors (lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric pancreatitis, respectively). While our understanding of AIP-1 has evolved considerably over the years, little is known about AIP-2 due to its rarity, often leading to misdiagnosis, delayed treatment, and even unnecessary surgical resection. Compared to AIP-1, AIP-2 exhibits distinct clinical and histologic features. Because AIP-2 is a pancreas-restricted disease without a specific serum marker, the evaluation of histologic features (e.g., granulocytic epithelial lesions) is essential for an accurate diagnosis. Patients with AIP-2 respond well to glucocorticoids, with anti-tumor necrosis factor-alpha antibodies as a promising alternative therapy. The prognosis of AIP-2 is generally favorable and relapse is uncommon. Here, we provide an overview of our current knowledge on the clinical features, diagnosis, therapeutic regimens, prognosis, and putative mechanisms underlying AIP-2. Notably, the diagnostic differentiation between AIP-2, especially the mass-forming/focal type, and pancreatic cancer is important, but challenging. In this regard, endoscopic ultrasound-guided core biopsy has a key role, but novel diagnostic markers and modalities are clearly needed.

Autoimmune pancreatitis and micronutrients

INTRODUCTION

Nutritional deficiencies, including fat-soluble vitamins and minerals have been detected in many autoimmune diseases, including those involving the digestive system, but have yet to be assessed in autoimmune pancreatitis (AIP). The aim of the present study was to determine the prevalence of micronutrient deficiencies in patients with AIP as well as to investigate their relationship with relapse.

PATIENTS AND METHODS

We retrospectively analysed medical records of patients treated for AIP. Demographic and clinical data were collected.

RESULTS

One hundred patients were included in the final analysis. The male-to-female ratio was 2.5:1; median age at diagnosis was 57 years (range 19-85). Median follow-up was 53 months, and during this time, 38% of patients suffered from at least one micronutrient deficiency. The most prevalent micronutrient deficiencies were vitamin D (16.1%) and zinc (25.5%). Relapse was observed in 37% of the AIP patients. Initial analysis showed that AIP relapse was associated with any micronutrient deficiency as well as zinc and vitamin D deficiency, but after stratifying for AIP type 1 and adjusting for PEI and elevated IgG4 levels, the association ceased to be statistically significant.

CONCLUSION

Zinc and vitamin D deficiencies may be common in patients with AIP, indicating that these micronutrients might play a role in the natural course of AIP. Importantly, any micronutrient deficiency may be prevalent even in the light of treated PEI, which emphasizes the potential of micronutrients as an additional tool in the workup and follow-up of AIP patients.

Autoimmune pancreatitis associated with inflammatory bowel diseases: A retrospectively bidirectional case-control study in China

OBJECTIVES

Autoimmune pancreatitis (AIP) is a rare and enigmatic immune-mediated inflammatory disease. We aimed to investigate the prevalence, characteristics, and associated factors of AIP-inflammatory bowel disease (IBD) in China.

METHODS

A retrospective bidirectional case-control study was performed. The diagnoses of IBD and AIP were made based on the European Crohn's and Colitis Organization guidelines and the International Consensus Diagnostic Criteria. IBD controls were matched by age, sex, and IBD type at a ratio of 1:4, while AIP controls were matched by AIP types.

RESULTS

The age-standardized prevalence of AIP-IBD patients in the IBD and AIP population were 292.0 and 8151.93 per 100 000 population, respectively. IBD patients had a higher risk of AIP compared to non-IBD patients (odds ratio 8.4, 95% confidence interval 4.7-14.9, P < 0.0001), and AIP patients had a higher risk of developing IBD compared to the general population in China. The mean age at diagnosis of IBD and AIP was 34.83 years and 40.42 years. IBD was diagnosed before AIP in seven cases. The median total IBD and AIP duration was 43.5 months and 13.5 months. Use of mesalamine and tuberculosis were associated with AIP in IBD patients (P = 0.031). And fecal occult blood test was associated with IBD in AIP patients (P = 0.008).

CONCLUSIONS

Most AIP-IBD patients had ulcerative colitis and type 2 AIP. IBD patients are more likely to develop AIP compared to the general population, and vice versa. Use of mesalamine and tuberculosis infection were associated with AIP, and fecal occult blood test was associated with IBD.

Case report: Induction and maintenance of steroid-free remission with vedolizumab in a case of steroid-dependent autoimmune pancreatitis

Autoimmune pancreatitis responds well to corticosteroids in most instances. Additional immunosuppression or low-dose maintenance steroids may be necessary upon relapse. There is limited data on alternative strategies when these regiments fail or cause adverse reactions. We report a case of a middle-aged woman with autoimmune pancreatitis in whom tapering of prednisolone below the dose of 25mg per day resulted in relapse of symptoms and long-term steroid use led to development of steroid induced hyperglycaemia. Induction and maintenance of steroid-free remission was ultimately successful under vedolizumab therapy. Remission has been stable for over one year with reduced need for antidiabetic intervention. This is the first reported case of treatment of refractory autoimmune pancreatitis with vedolizumab. It highlights the overlap of immunological mechanisms within inflammatory diseases of the digestive tract and how knowledge of biological data can inform treatment decisions for individual cases. The demonstrated efficacy of vedolizumab and low risk of severe side effects warrant further investigation into its use in autoimmune pancreatitis.

Is Surgery in Autoimmune Pancreatitis Always a Failure?

Autoimmune pancreatitis is a rare form of chronic pancreatitis of presumed autoimmune etiology. Due to significant overlap in clinical and imaging characteristics, misdiagnosis as a pancreatic malignancy is common. As a result, a significant number of patients undergo a major pancreatic resection, associated with considerable morbidity, for a disease process that generally responds well to corticosteroid therapy. In the past ten years, important advances have been made in understanding the disease. Several diagnostic criteria have been developed to aid in diagnosis. Despite this, pancreatic resection may still be required in a subset of patients to reliably exclude pancreatic malignancy and establish a definite diagnosis of autoimmune pancreatitis. This article aimed to define the role of surgery in autoimmune pancreatitis, if any. For this purpose, published case series of patients with a diagnosis of autoimmune pancreatitis, based on the histopathological examination of surgical specimens, were reviewed and patients' clinical, radiological and serological details were assessed. At the end, histopathologic examinations of patients who underwent pancreatic resection at our department in the last 10 years were retrospectively reviewed in order to identify patients with autoimmune pancreatitis and assess their clinical characteristics.