Retrospective Cohort Study
Copyright ©The Author(s) 2023. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Sep 21, 2023; 29(35): 5125-5137
Published online Sep 21, 2023. doi: 10.3748/wjg.v29.i35.5125
Clinical characteristics and outcome of autoimmune pancreatitis based on serum immunoglobulin G4 level: A single-center, retrospective cohort study
Guan-Zhou Zhou, Jia-Qi Zeng, Lei Wang, Miao Liu, Ke Meng, Zi-Kai Wang, Xiu-Li Zhang, Li-Hua Peng, Bin Yan, Fei Pan
Guan-Zhou Zhou, Jia-Qi Zeng, Ke Meng, Zi-Kai Wang, Xiu-Li Zhang, Li-Hua Peng, Bin Yan, Fei Pan, Department of Gastroenterology and Hepatology, The First Medical Center, Chinese PLA General Hospital, Beijing 100853, China
Guan-Zhou Zhou, School of Medicine, Nankai University, Tianjin 300071, China
Jia-Qi Zeng, Chinese PLA Medical School, Beijing 100853, China
Lei Wang, Department of Rheumatology, The First Medical Center, Chinese PLA General Hospital, Beijing 100853, China
Miao Liu, Department of Statistics and Epidemiology, Graduate School, Chinese PLA General Hospital, Beijing 100853, China
Author contributions: Pan F contributed to study conceptualization and reviewed the manuscript; Zhou GZ and Zeng JQ drafted the initial manuscript and reviewed the manuscript; Wang L and Liu M contributed to methodology and formal analysis; Zhou GZ, Yan B and Meng K contributed to data collection; Wang ZK, Zhang XL and Peng LH reviewed the manuscript; All authors approved the final manuscript as submitted, all authors had full access to the data in the present study and accept responsibility to submit for publication.
Supported by Young Scholar Independent Innovation Science Fund of Chinese PLA General Hospital, No. 22QNCZ020; National Key Research and Development Program, No. 2022YFC2504003.
Institutional review board statement: The study was reviewed and approved for publication by our Institutional Reviewer.
Informed consent statement: As the study used anonymous and pre-existing data, the requirement for the informed consent from patients was waived.
Conflict-of-interest statement: All the Authors have no conflict of interest related to the manuscript.
Data sharing statement: The original anonymous dataset is available on request from the corresponding author at panfei@plagh.org.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Open-Access: This article is an open-access article that was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution NonCommercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: https://creativecommons.org/Licenses/by-nc/4.0/
Corresponding author: Fei Pan, MD, PhD, Associate Chief Physician, Associate Professor, Department of Gastroenterology and Hepatology, The First Medical Center, Chinese PLA General Hospital, No. 28 Fuxing Road, Beijing 100853, China. panfei@plagh.org
Received: May 22, 2023
Peer-review started: May 22, 2023
First decision: July 8, 2023
Revised: July 21, 2023
Accepted: September 1, 2023
Article in press: September 1, 2023
Published online: September 21, 2023
Processing time: 115 Days and 6.1 Hours
Abstract
BACKGROUND

Autoimmune pancreatitis (AIP) has been linked with elevated immunoglobulin (Ig) G4 levels. The characteristics and outcomes of AIP based on serum markers have not been fully evaluated.

AIM

To compare clinical features, treatment efficacy, and outcome of AIP based on serum IgG4 levels and analyze predictors of relapse.

METHODS

A total of 213 patients with AIP were consecutively reviewed in our hospital from 2006 to 2021. According to the serum IgG4 level, all patients were divided into two groups, the abnormal group (n = 148) with a high level of IgG4 [> 2 × upper limit of normal (ULN)] and the normal group (n = 65). The t-test or Mann-Whitney U test was used to compare continuous variables. Categorical parameters were compared by the χ2 test or Fisher’s exact test. Kaplan-Meier curves and log-rank tests were established to assess the cumulative relapse rates. Univariate and multivariate analyses were used to investigate potential risk factors of AIP relapse.

RESULTS

Compared with the normal group, the abnormal group had a higher average male age (60.3 ± 10.4 vs 56.5 ± 12.9 years, P = 0.047); higher level of serum total protein (72.5 ± 7.9 g/L vs 67.2 ± 7.5 g/L, P < 0.001), IgG4 (1420.5 ± 1110.9 mg/dL vs 252.7 ± 106.6 mg/dL, P < 0.001), and IgE (635.6 ± 958.1 IU/mL vs 231.7 ± 352.5 IU/mL, P = 0.002); and a lower level of serum complement C3 (100.6 ± 36.2 mg/dL vs 119.0 ± 45.7 mg/dL, P = 0.050). In addition, a lower number of cases with abnormal pancreatic duct and pancreatic atrophy (23.6% vs 37.9%, P = 0.045; 1.6% vs 8.6%, P = 0.020, respectively) and a higher rate of relapse (17.6% vs 6.2%, P = 0.030) were seen in the abnormal group. Multivariate analyses revealed that serum IgG4 [(> 2 × ULN), hazard ratio (HR): 3.583; 95% confidence interval (CI): 1.218–10.545; P = 0.020] and IgA (> 1 × ULN; HR: 5.908; 95%CI: 1.199–29.120; P = 0.029) and age > 55 years (HR: 2.383; 95%CI: 1.056–5.378; P = 0.036) were independent risk factors of relapse.

CONCLUSION

AIP patients with high IgG4 levels have clinical features including a more active immune system and higher relapse rate. Several factors, such as IgG4 and IgA, are associated with relapse.

Keywords: Autoimmune pancreatitis; Immunoglobulin G4; Clinical characteristics; Outcome; Relapse; Cohort study

Core tip: Our findings suggested that patients with a high immunoglobulin (Ig) G4 level had different clinical features including a more active immune system and higher relapse rate. Patients with normal IgG4 level still require attention because they have a high incidence of jaundice and pancreatic atrophy. Some factors were identified as risk factors for relapse, such as age > 55 years [hazard ratio (HR) 2.383; 95% confidence interval (CI) 1.056-5.378; P = 0.036], high IgG4 level [> 2 × upper limit of normal (ULN) (HR 3.583; 95%CI 1.218-10.545; P = 0.020) and high IgA level (> 1 × ULN) (HR 5.908; 95%CI 1.199-29.120; P = 0.029).