Prediction and Management for Relapse of Type 1 Autoimmune Pancreatitis After Initial Steroid Treatment: A Long-Term Follow-up From China

Clinical features and long-term prognosis of type 1 autoimmune pancreatitis based on the location of bile duct lesions

BACKGROUND/PURPOSE

Type 1 autoimmune pancreatitis (AIP) frequently involves biliary lesions and poses diagnostic and therapeutic challenges. We aimed to evaluate the clinical features and long-term prognosis of type 1 AIP with a focus on the locations of bile duct lesions.

METHODS

In this retrospective study, 159 patients with type 1 AIP were included. Patients were classified on the basis of the location of bile duct strictures, and clinical outcomes, including relapse rates and steroid dependency, were analyzed.

RESULTS

Eighty-nine (56%) patients had bile duct involvement. Forty-nine patients (30.8%) experienced relapse, with a significantly higher cumulative relapse rate in cases of stricture or wall thickening upstream of the intrapancreatic bile duct (3 years: 24% vs. 37.1%, p < .001). These patients also had a significantly higher rate of two or more relapses than did the patients without stricture or wall thickening (5.1% vs. 19.5%, p = .01). Two patients with stricture and dilation up to the intrahepatic bile ducts became steroid-dependent and were treated with azathioprine.

CONCLUSIONS

Patients with type 1 AIP with biliary lesions involving upstream strictures or wall thickening, especially those with stricture and dilation extending into the intrahepatic bile ducts, are at high risk of relapse and may become steroid dependent.

Potential Added Value of 18F-FDG PET Metabolic Parameters in Predicting Disease Relapse in Type 1 Autoimmune Pancreatitis

BACKGROUND

The predictive value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) metabolic parameters for predicting AIP relapse is currently unknown. This study firstly explored the value of 18F-FDG PET/CT parameters as predictors of type 1 AIP relapse.

METHODS

This multicenter retrospective cohort study analyzed 51 patients who received 18F-FDG PET/CT prior to treatment and did not receive maintenance therapy after remission. The study collected baseline characteristics and clinical data and conducted qualitative and semi-quantitative analysis of pancreatic lesions and extrapancreatic organs. The study used three thresholds to select the boundaries of pancreatic lesions to evaluate metabolic parameters, including the maximum standard uptake value (SUVmax), mean standard uptake value (SUVmean), total lesion glycolysis (TLG), metabolic tumor volume (MTV), and tumor-to-normal liver standard uptake value ratio (SUVR). Univariate and multivariate analyses were performed to identify independent predictors and build a recurrence prediction model. The model was internally validated using the bootstrap method and a nomogram was created for clinical application.

RESULTS

In the univariable analysis, the relapsed group showed higher levels of SUVmax (6.0 ± 1.6 vs. 5.2 ± 1.1; P = 0.047), SUVR (2.3 [2.0-3.0] vs. 2.0 [1.6-2.4]; P = 0.026), and TLG2.5 (234.5 ± 149.1 vs. 139.6 ± 102.5; P = 0.020) among the 18F-FDG PET metabolic parameters compared to the non-relapsed group. In the multivariable analysis, serum IgG4 (OR, 1.001; 95% CI, 1.000-1.002; P = 0.014) and TLG2.5 (OR, 1.007; 95% CI, 1.002-1.013; P = 0.012) were independent predictors associated with relapse of type 1 AIP. A receiver-operating characteristic curve of the predictive model with these two predictors demonstrated an area under the curve of 0.806.

CONCLUSION

18F-FDG PET/CT metabolic parameters, particularly TLG2.5, are potential predictors for relapse in patients with type 1 AIP. A multiparameter model that includes IgG4 and TLG2.5 can enhance the ability to predict AIP relapse.

Characteristics of mass-forming autoimmune pancreatitis commonly misdiagnosed as a malignant tumor

Objective

This study aimed to explore the clinical characteristics and differential diagnosis of patients with autoimmune pancreatitis (AIP) and pancreatic cancer to prevent misdiagnosis and mistreatment.

Methods

The clinical data of patients with AIP with suspected pancreatic or bile duct malignancy and pancreatic cancer were retrospectively analyzed. The risk factors and the diagnostic value of IgG4 and Tbil levels before treatment for AIP was investigated. Moreover, the imaging features and response to hormone therapy were analyzed.

Results

AIP was commonly observed in men. Compared to patients with pancreatic cancer, the incidence of poor appetite and weight loss and carbohydrate antigen 19-9 (CA19-9) level was lower in patients with AIP, while the immunoglobulin G4 (IgG4) level was higher (p < 0.05). After treatment, the IgG4 and CA19-9 levels in patients with AIP were decreased (p < 0.001). IgG4 level before treatment (OR = 2.452, 95%CI: 1.180-5.096, P = 0.016) and total bilirubin (Tbil) level before treatment (OR = 0.992, 95%CI: 0.985-0.998, P = 0.013) were independent risk factors of AIP. Furthermore, the diagnostic value of IgG4 level before treatment, Tbil level before treatment, IgG4/Tbil before treatment, and a combination of these indicators was high. Moreover, 15 (68.18%) patients with AIP had space-occupying lesions of the pancreas, and 16 (72.73%) had autoimmune cholangitis. Most patients with AIP were sensitive to hormone therapy.

Conclusions

The Tbil and IgG4 levels, imaging findings, and hormone therapy reactivity could differentiate AIP from pancreatic cancer. A combination of IgG4, Tbil, and IgG4/Tbil before treatment might be a promising diagnostic biomarker for AIP.

The M-ANNHEIM-AiP-Activity-Score is useful for predicting relapse in patients with type 1 autoimmune pancreatitis

BACKGROUND/OBJECTIVES

Proper assessment of disease activity and prediction of relapse are crucial for the management of autoimmune pancreatitis (AIP). The M-ANNHEIM-AiP-Activity-Score (MAAS) has been proposed to determine disease activity and predict relapse in German and Swedish patients with AIP. MAAS is calculated using six categories: pain report, pain control, exocrine insufficiency, endocrine insufficiency, imaging, and complications. This study aimed to clarify the usefulness of MAAS to predict relapse in Japanese patients with type 1 AIP.

METHODS

We retrospectively analyzed 117 patients with type 1 AIP undergoing initial and maintenance steroid treatments at our institute between April 2006 and March 2021. AIP was diagnosed according to the Japanese Diagnostic Criteria for AIP 2018. We examined the association of MAAS with relapse during and after maintenance treatment.

RESULTS

MAAS (median, 8 points) at the start of the initial treatment was reduced after treatment (median, 4 points; P < 0.001). A MAAS ≥11 points at the start of the initial treatment was associated with relapse. The initial treatment-induced reduction of MAAS<60% was more frequent in patients with relapse (75.0%) than in patients without relapse (37.6%; P = 0.007). MAAS at the start of maintenance treatment was higher for patients with relapse (median, 5 points) than that for patients without relapse (median, 4 points; P = 0.007). MAAS ≥4 points at the start of maintenance treatment was associated with subsequent relapse.

CONCLUSIONS

MAAS is useful for predicting relapse in patients with type 1 AIP undergoing maintenance therapy.

Update on classification, diagnosis, and management of immunoglobulin G4-related disease

Immunoglobulin G4-related disease (IgG4-RD) is a newly recognized chronic fibro-inflammatory autoimmune disease, and its recognition has been constantly increasing worldwide over the last few years. A correct and timely recognition, as well as appropriate intervention, is crucial for the treatment of IgG4-RD. For certain subtypes of IgG4-RD, organ-specific criteria are formulated to make the diagnosis more accurate. New biomarkers have emerged in the recent years to aid the disease diagnosis, its prognosis prediction, as well as therapy response monitoring. Although recurrence is very common in IgG4-RD, glucocorticoid is still the first-line treatment for the majority of patients. The factors that affect the likelihood of disease relapse are multifaceted. The selection strategy of various steroid-sparing agents is still being explored. Besides, when patients have special sites involvement leading to severe clinical conditions, surgical operation or interventional therapy should also be considered. An update on classification, diagnosis, and management of IgG4-RD is provided in the current study to fully elucidate the recommended clinical practice of this mysterious disease.

The clinical efficacy of azathioprine as maintenance treatment for autoimmune pancreatitis: a systematic review and meta-analysis

The effectiveness of azathioprine (AZA) in preventing relapse and maintaining autoimmune pancreatitis (AIP) remission has been reported; however, most of these studies are case series with no randomized control trials available in the literature. Therefore, this study performed a systematic review and meta-analysis of the existing literature on this subject to determine the clinical efficacy of AZA as maintenance therapy for AIP patients. A systematic search was performed to identify studies on the clinical efficacy of AZA as maintenance therapy in AIP patients. The crude multiple relapse rate was estimated to assess the ability of AZA to control relapses in AIP. Pooled estimates were obtained using a random-effects model with the DerSimonian-Laird method. We identified AIP patients who did not respond to initial steroid treatment, experienced steroid weaning failure, or those who relapsed during remission as refractory cases. After reviewing the studies, ten articles fulfilled the inclusion criteria and were selected for meta-analysis. Of all 4504 patients, 3534 patients were treated with steroids, and 346 patients were treated with AZA for relapsed AIP. In this meta-analysis, 14/73 (19.2%) patients receiving AZA for refractory AIP relapsed. Meanwhile, 14/47 (29.8%) patients without AZA experienced relapse. The integrated odds ratio for relapse risk in patients receiving AZA was estimated to be 0.52 (p = 0.15). This systematic review and meta-analysis demonstrated the efficacy of AZA in preventing relapse of AIP, which supports the use of AZA as a maintenance treatment in patients with AIP who relapse upon withdrawal of steroid therapy.

Determination of the duration of glucocorticoid therapy in type 1 autoimmune pancreatitis: A systematic review and meta-analysis

BACKGROUND

The indications for maintenance glucocorticoid therapy (MGT) and its duration after initial remission of type 1 autoimmune pancreatitis (AIP) remain controversial. In contrast to the Japanese treatment protocol, the Mayo protocol does not recommend MGT after initial remission. This study aimed to evaluate the relapse rate in patients with type 1 AIP according to the duration of glucocorticoid therapy.

METHODS

We conducted a systematic literature review up until November 30, 2020, and identified 40 studies reporting AIP relapse rates. The pooled relapse rates were compared between groups according to the protocol and duration of glucocorticoids (routine vs. no MGT; glucocorticoids ≤6 months vs. 6-12 months vs. 12-36 months vs. ≥ 36 months). The pooled rates of adverse events related to glucocorticoids were also evaluated.

RESULTS

Meta-analysis indicated calculated pooled relapse rates of 46.6% (95% confidence interval (CI), 38.9-54.3%) with glucocorticoids for ≤ 6 months, 44.3% (95% CI, 38.8-49.8%) for 6-12 months, 34.1% (95% CI, 28.6-39.7%) for 12-36 months, and 27.0% (95% CI, 23.4-30.6%) for ≥ 36 months. The rate of relapse was also significantly lower in patients with routine-use protocol of MGT (31.2%; 95% CI, 27.5-34.8%) than in patients with no MGT protocol (44.1%; 95% CI, 35.8-52.4%). Adverse events were comparable between groups.

CONCLUSIONS

The rate of relapse tended to decrease with extended durations of glucocorticoid therapy up to 36 months. Clinicians may decide the duration of glucocorticoids according to patient condition, including comorbidities and risk of relapse.

Steroid Therapy and Steroid Response in Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP), a unique subtype of pancreatitis, is often accompanied by systemic inflammatory disorders. AIP is classified into two distinct subtypes on the basis of the histological subtype: immunoglobulin G4 (IgG4)-related lymphoplasmacytic sclerosing pancreatitis (type 1) and idiopathic duct-centric pancreatitis (type 2). Type 1 AIP is often accompanied by systemic lesions, biliary strictures, hepatic inflammatory pseudotumors, interstitial pneumonia and nephritis, dacryoadenitis, and sialadenitis. Type 2 AIP is associated with inflammatory bowel diseases in approximately 30% of cases. Standard therapy for AIP is oral corticosteroid administration. Steroid treatment is generally indicated for symptomatic cases and is exceptionally applied for cases with diagnostic difficulty (diagnostic steroid trial) after a negative workup for malignancy. More than 90% of patients respond to steroid treatment within 1 month, and most within 2 weeks. The steroid response can be confirmed on clinical images (computed tomography, ultrasonography, endoscopic ultrasonography, magnetic resonance imaging, and 18F-fluorodeoxyglucose-positron emission tomography). Hence, the steroid response is included as an optional diagnostic item of AIP. Steroid treatment results in normalization of serological markers, including IgG4. Short- and long-term corticosteroid treatment may induce adverse events, including chronic glycometabolism, obesity, an immunocompromised status against infection, cataracts, glaucoma, osteoporosis, and myopathy. AIP is common in old age and is often associated with diabetes mellitus (33-78%). Thus, there is an argument for corticosteroid therapy in diabetes patients with no symptoms. With low-dose steroid treatment or treatment withdrawal, there is a high incidence of AIP recurrence (24-52%). Therefore, there is a need for long-term steroid maintenance therapy and/or steroid-sparing agents (immunomodulators and rituximab). Corticosteroids play a critical role in the diagnosis and treatment of AIP.

Glucocorticoids and steroid sparing medications monotherapies or in combination for IgG4-RD: a systematic review and network meta-analysis

Objective

To assess the safety and efficacy of glucocorticoids (GCs), immunosuppressive agents (IM) and rituximab (RTX), alone or in combination, for the treatment of IgG4-RD.

Methods

Relevant articles published were searched in the databases with relevant key words. Network meta-analysis was conducted, with various outcomes including relapse rate, remission rate and adverse events. Data were calculated with odds ratio (ORs) and 95% CI. P-score was used to rank the treatments.

Results

A total of 15 studies involving 1169 patients were included. Network meta-analysis indicated that RTX maintenance therapy had the lowest relapse rate of all treatments (OR = 0.10, 95% CI [0.01, 1.63]), whereas GCs + IM was associated with a lower relapse rate compared with GCs alone (OR = 0.39, 95% CI [0.20, 0.80]). Further, patients treated with GCs + IM had a higher remission rate than those given GCs (OR= 3.36, 95% CI [1.44, 7.83]), IM (OR= 55.31, 95% CI [13.73, 222.73]) monotherapies or RTX induction therapy only (OR= 7.38, 95% CI [1.56, 34.94]). The rate of adverse events was comparable among the different treatment groups.

Conclusion

Treatment of IgG4-RD patients with GCs and IM was associated with higher remission rates and lower relapse rates, as well as comparable safety profiles compared with GC, IM and RTX induction therapy. RTX maintenance therapy had a larger reduction in the relapse rate compared with GC and IM. The current evidence should be carefully scrutinized as the included studies were observational in design. Larger randomized controlled trials are needed to confirm.