Relapse patterns and predictors of IgG4‐related diseases involved with autoimmune pancreatitis: A single‐center retrospective study of 115 patients

Abstract

Objective Autoimmune pancreatitis is an autoimmune disorder accompanied by clinicopathological manifestations that have been established as immunoglobulin (IgG)4‐related diseases (IgG4‐RD). Other IgG4‐RD are often involved with autoimmune pancreatitis. They sometimes relapse despite a favorable response to steroid therapy. This study aimed to clarify the patterns and risk factors for extrapancreatic relapse. Methods We reviewed the data of 115 patients diagnosed with definite autoimmune pancreatitis type 1 and followed up for > 1 year. We analyzed two items: the timing and pattern of extrapancreatic relapse, and risk factors for relapse with three common manifestations: IgG4‐related sclerosing cholangitis (SC), IgG4‐related dacryoadenitis and sialadenitis (DS), and IgG4‐related retroperitoneal fibrosis (RF). Results Remission was achieved in all patients, except one. The extrapancreatic relapse rates were 11.0%, 19.7%, and 40% within 3, 5, and 10 years, respectively. Of 26 patients with extrapancreatic relapse, nine (34.6%) relapsed with a new IgG4‐RD. Based on multivariate analysis, the interval between symptom onset and steroid initiation, and the presence of RF at onset were significant risk factors for relapse with SC and RF, respectively. Conclusions Our results indicate that they may be various extrapancreatic relapse patterns especially in autoimmune pancreatitis with other organ involvement. Patients with a delayed initiation of steroids or RF at onset should be carefully followed up as high‐risk groups for SC and RF relapse.

Steroid Therapy and Steroid Response in Autoimmune Pancreatitis

“…As mentioned above, relapse occurs in 24-52% of type 1 AIP cases [22,29,[72][73][74][79][80][81][136][137][138][139][140][141][142][143][144] and 0-27% of type 2 AIP cases [21,73,78] after cessation of corticosteroid treatment or dose tapering of corticosteroids. Identification of characteristics or risk factors for relapse is critical, as unnecessary steroid treatment in patients in whom recurrence is unlikely should be avoided.…”

“…To date, several factors for predicting AIP relapse have been reported. These include a high level of serum IgG4 [22,79]; extrapancreatic lesions [78,80,136,137], especially proximal bile duct stenosis [73,136,138]; retroperitoneal fibrosis [139]; dacryoadenitis/sialadenitis [140]; jaundice [141]; discontinuation of steroid therapy [138,142,143]; a small reduction in the level of serum sIgG4 3-4 months after steroid initiation [80,81]; and a low level of pancreatic shrinkage following steroid treatment [144]. Maintenance corticosteroid therapy, with or without steroid-sparing agents, is recommended for type 1 AIP patients with factors predictive of relapse, although the therapeutic period is unclear.…”

The Clinical Utility of Soluble Serum Biomarkers in Autoimmune Pancreatitis: A Systematic Review

“…There are a number of extrapancreatic manifestations correlated with IgG4 level [ 39 ]. Additionally, different organs seem to be involved based on the extent of IgG4 elevation [ 44 , 61 ]. The study by Ishikawa et al [ 42 ] revealed that all patients with AIP with kidney involvement displayed elevated IgG4, of whom 81% ( n = 17) had IgG4 higher than twice the ULN.…”

“…The study by Ishikawa et al [ 42 ] revealed that all patients with AIP with kidney involvement displayed elevated IgG4, of whom 81% ( n = 17) had IgG4 higher than twice the ULN. Retroperitoneal fibrosis and lacrimal and salivary gland involvement are also accompanied by high IgG4 levels in patients with AIP [ 32 , 61 , 106 ]. Studies that investigate the relationship between IgG4 and the extension of extrapancreatic lesions in AIP are presented in Supplemental Table S2 .…”

“…There are a number of extrapancreatic manifestations correlated with IgG4 level [39]. Additionally, different organs seem to be involved based on the extent of IgG4 elevation [44,61]. The study by Ishikawa et al [42] revealed that all…”