Allergic manifestations in autoimmune pancreatitis

Retroperitoneal fibrosis

Retroperitoneal fibrosis (RPF) is a condition characterized by the presence of inflammation and fibrosis in the retroperitoneal space, for which no standard diagnostic criteria exist. Historically, treatment has focused on relieving the obstruction with percutaneous or cystoscopic assisted placement of ureteral stents followed by more definitive resolution of ureteric obstruction with open or laparoscopic ureterolysis. However, over the past several years management has shifted from primarily a surgical approach to an immunosuppressive-based therapy aimed at modulation of the immune system. This review focuses on the recent advances in the classification, epidemiology, pathophysiology, pathology, imaging, and treatment of RPF.

Rethinking Ormond's disease: "idiopathic" retroperitoneal fibrosis in the era of IgG4-related disease

Idiopathic retroperitoneal fibrosis (RPF) is a periaortic sclerotic disease that encases adjacent retroperitoneal structures, particularly the ureters. A subset of idiopathic RPF cases can be associated with IgG4-related disease, but the frequency of this association is not clear. We selected 23 cases of idiopathic RPF and identified IgG4-related RPF cases based on the presence of IgG4+ plasma cells in the tissue, using an IgG4/IgG ratio cutoff of >40%. We then compared the IgG4-related RPF patients and the non-IgG4-related RPF patients in terms of both the presence of histopathologic features typical of IgG4-related disease and the simultaneous occurrence (or history) of other organ manifestations typical of IgG4-related disease. The IgG4-related RPF and non-IgG4-related RPF groups were also analyzed in terms of clinical, laboratory, and radiologic features and treatment review. We identified 13 cases of IgG4-related RPF (57% of the total cohort). The distinguishing features of IgG4-related RPF were histopathologic and extra-organ manifestations of IgG4-related disease. The IgG4-related RPF patients were statistically more likely than non-IgG4-related RPF patients to have retroperitoneal biopsies showing lymphoplasmacytic infiltrate (p = 0.006), storiform fibrosis (p = 0.006), or tissue eosinophilia (p = 0.0002). Demographics of the 2 groups, including a middle-aged, male predominance (mean age, 58 yr; 73% male), were similar. IgG4-related disease accounts for a substantial percentage of patients with "idiopathic" RPF. Histopathologic features such as storiform fibrosis, obliterative phlebitis, and tissue eosinophilia are critical to identifying this disease association. Extraretroperitoneal manifestations of IgG4-related disease are also often present among patients with IgG4-related RPF. Elevated IgG4/total IgG ratios in tissue biopsies are more useful than the number of IgG4+ plasma cells per high-power field in cases of RPF that are highly fibrotic.

Clinical features of 10 patients with IgG4-related retroperitoneal fibrosis

OBJECTIVE

To elucidate the clinical characteristics of IgG4-related retroperitoneal fibrosis (RF).

METHODS

IgG4-related RF was diagnosed when all of the following three criteria were fulfilled: retroperitoneal soft tissue masses surrounding the aorta and/or adjacent tissues, elevation of the serum IgG4 levels, and abundant infiltration of IgG4-positive plasma cells in at least one organ or site. Ten patients were diagnosed as having IgG4-related RF.

RESULTS

The mean age at diagnosis was 70.1 years, and the male-to-female ratio was 1:0.6. Only two patients had initial symptoms predominantly related to RF (back pain and edema of the lower extremities), while the remaining eight patients reported initial symptoms due to associated diseases. On laboratory examination, a severe inflammatory reaction was observed in one patient. Elevation of the levels of serum IgG and IgE, eosinophilia and positivity of antinuclear antibodies were detected in seven, five, two and seven patients, respectively. The retroperitoneal masses were detected primarily in the left renal hilus in four patients, in the periaortic region in five patients and in both regions in one patient. Hydronephrosis was present in five patients. The histological diagnosis was confirmed in the retroperitoneal masses (resection, n=1 biopsy, n=2) and extraretroperitoneal lesions (n=7). Twenty-four other IgG4-related diseases were found to be associated with IgG4-related RF in nine patients (autoimmune pancreatitis (n=2), sialadenitis (n=4), dacryoadenitis (n=5), lymphadenopathy (n=9), pulmonary pseudotumor (n=1) and pituitary pseudotumor (n=1)). Seven patients underwent steroid therapy, all of whom responded well and showed no instances relapse.

CONCLUSION

IgG4-related RF has several clinical characteristic features. Our diagnostic criteria may be helpful in obtaining a correct diagnosis.

Rare diagnosis of IgG4-related systemic disease by lip biopsy in an international Sjögren syndrome registry

IgG4-related disease has been recently defined as a distinct clinic-pathologic entity, characterized by dense IgG-4 plasmacytic infiltration of diverse organs, fibrosis, and tumefactive lesions. Salivary and lacrimal glands are a target of this disease and, when affected, may clinically resemble Küttner tumor, Mikulicz disease, or orbital inflammatory pseudotumor. In some patients, the disease is systemic, with metachronous involvement of multiple organs, including the pancreas, aorta, kidneys, and biliary tract. We report a 66-year-old man who presented with salivary gland enlargement and severe salivary hypofunction and was diagnosed with IgG4-related disease on the basis of a labial salivary gland biopsy. Additional features of his illness included a marked peripheral eosinophilia, obstructive pulmonary disease, and lymphoplasmacytic aortitis. He was evaluated in the context of a research registry for Sjögren syndrome and was the only 1 of 2594 registrants with minor salivary gland histopathologic findings supportive of this diagnosis.

Is IgG4-Related Disease a Cause of Xerostomia? A Cohort Study of 60 Patients

Objective. Immunoglobulin-G4-(IgG4-) related disease (IgG4 RD) is a fibrosing process characterized by a significant infiltration of IgG4-secreting plasma cells. IgG4 RD can affect almost all organs including salivary glands. Whether IgG4 RD plays a role in the development of sicca syndrome and particularly dry mouth syndrome remains to be investigated. Methods. We conducted a monocentric cohort study for two years to search for IgG4 RD features in patients with dry mouth syndrome using immunostainings of labial salivary gland specimens with anti-IgG4 antibody. Results. Among 60 patients presenting with dry mouth syndrome who underwent labial salivary gland biopsy, 18 showed positive immunostaining with the anti-IgG4 antibody including 4 patients with typical systemic IgG4 RD. Five also fulfilled criteria for Sjögren's syndrome. Conclusion. These findings suggest that clinical forms of IgG4 RD salivary involvement without salivary swelling may occur. This salivary involvement is probably overlooked in everyday practice and could represent a mild form of IgG4 RD.

IgG4-related disease: can non-classical histopathological features or the examination of clinically uninvolved tissues be helpful in the diagnosis?

IgG4-related disease (IgG4-RD) is an increasingly recognised inflammatory and fibrosing condition that commonly shows multisystem involvement. The disease may mimic malignancy and other inflammatory or immune-mediated disorders, but usually has a good response to corticosteroid therapy, underlining the requirement for recognition of the condition. Accurate diagnosis requires careful interpretation of varying combinations of serum IgG4 levels, radiological features and characteristic histopathological appearances within an appropriate clinical setting. The presence of 'classical' histopathological features together with an elevated tissue IgG4+ plasma cell count and IgG4 to IgG ratio is often diagnostic and at the very least can strongly support a clinicopathological diagnosis of IgG4-RD. The authors describe the most recent diagnostic criteria for IgG4-RD, especially the histopathological features. The authors then discuss the merits of examining tissues that may be more easily obtainable than those that commonly show the 'classical' histopathological features, but within which not all of these 'diagnostic' features may be present. The authors conclude that while a combination of 'classical' histopathological features and an elevated tissue IgG4+ plasma cell count is the gold standard for diagnosis, examination of tissues that show some but not all of these features can, in the appropriate context, provide useful supporting evidence for a clinicopathological diagnosis of IgG4-RD.

Three cases of bronchial asthma preceding IgG4-related autoimmune pancreatitis

BACKGROUND

Autoimmune pancreatitis is characterized by diffuse swelling of the pancreas and a high serum immunoglobulin (Ig) G4 concentration. Histopathologically, dense infiltration of lymphocytes and IgG4-positive plasma cells with fibrosis are seen in the pancreas. Although allergic diseases complicating autoimmune pancreatitis have been reported, the clinical features of bronchial asthma complicated by autoimmune pancreatitis remain unclear.

CASE SUMMARY

We report three cases of bronchial asthma preceding the onset of type 1 autoimmune pancreatitis by 3 months to 30 years. All three cases were males with high serum IgG, IgG4, and IgE concentrations. The radioallergosorbent tests were positive for common allergens such as mites and house dust. One case had a pulmonary manifestation that proved to be an inflammatory pseudotumor of the lung with an accumulation of IgG4-positive plasma cells. The asthma symptom was ameliorated by oral prednisolone therapy for autoimmune pancreatitis, and when the corticosteroid doses were reduced, asthma became worse in all three cases.

DISCUSSION

It is possible that atopy and increased Th2 cell activity are related to a higher coincidence of IgG4-related diseases such as type 1 autoimmune pancreatitis. Because the present cases are few in number, further studies are necessary.

Churg-Strauss syndrome complicated by chronic periaortitis: a case report and review of the literature

We present a case of Churg-Strauss syndrome complicated by chronic periaortitis. A 68-year-old man presented with wheezing, dyspnea, purpurae, and numbness of the extremities. Antineutrophil cytoplasmic antibodies were absent; however, eosinophilia, a pulmonary infiltrative shadow on chest X-ray, eosinophilic vasculitis on histologic examination of skin and kidney, and mononeuritis multiplex were detected. Churg-Strauss syndrome was diagnosed. Contrast-enhanced abdominal computed tomography revealed a periaortic soft tissue mass extending from the subphrenic abdominal aorta to the proximal area of the bilateral iliac arteries. This indicated chronic periaortitis, probably caused by vasculitic activities. Both disorders improved with steroid therapy.

Pathogenesis of IgG4-related disease

PURPOSE OF REVIEW

To review studies that have examined underlying genetic and immunological aspects of IgG4-related disease.

RECENT FINDINGS

Genetic studies have suggested that several human leukocyte antigen (HLA) and non-HLA haplotypes/genotypes are associated with susceptibility to IgG4-related disease or to disease relapse after steroid therapy. Among several autoantibodies identified so far, autoantibodies against lactoferrin and carbonic anhydrase II are most frequently detected in serum of IgG4-disease patients. However, it has not been well clarified whether or not those autoantibodies belong to an IgG4 subclass. Studies that have demonstrated molecular mimicry between Helicobacter pylori and constituents of pancreatic epithelial cells suggest that gastric H. pylori infection triggers autoimmune pancreatitis in genetically predisposed individuals through antibody cross-reactivity. Recently, T-helper 2 immune reaction has been suggested to be predominant in IgG4-related disease. Interestingly, regulatory immune reactions are activated in IgG4-related disease, and regulatory cytokines interleukin-10 and transforming growth factor-b have been suggested, respectively, to play important roles in IgG4 class switch and fibroplasia.

SUMMARY

Autoimmunity has been considered the most probable pathogenesis of IgG4-related disease, but has not been completely proved so far. A breakthrough study to detect a specific autoantigen, autoantibody, or pathogen is necessary.

A clinical overview of IgG4-related systemic disease

PURPOSE OF REVIEW

To summarize the existing knowledge of various clinical presentations of IgG4-related systemic disease (IgG4-RSD) and to review the evolving list of organs affected by IgG4-RSD.

RECENT FINDINGS

The term IgG4-RSD encompasses a variety of clinical entities once regarded as being entirely separate diseases. The list of organs associated with this condition is growing steadily. Tissue biopsies reveal striking histopathological similarity, regardless of which organ is involved, although subtle differences across organs exist. Diffuse lymphoplasmacytic infiltrates, presence of abundant IgG4-positive plasma cells and extensive fibrosis are the hallmark pathology findings. Tumorous swelling, eosinophilia, and obliterative phlebitis are other frequently observed features. Polyclonal elevations of serum IgG4 are found in most but not all patients.

SUMMARY

IgG4-RSD is an underrecognized condition about which knowledge is now growing rapidly. Yet there remain many unknowns with regard to its cause, pathogenesis, various clinical presentations, approach to treatment, disease monitoring, and long-term outcomes. A wide variety of organs can be involved in IgG4-RSD. Clinicians should be aware of this entity and consider the diagnosis in the appropriate settings.

Serial changes of elevated serum IgG4 levels in IgG4-related systemic disease

OBJECTIVE

Autoimmune pancreatitis (AIP) and Mikulicz's disease have recently been recognized as pancreatic or salivary gland lesions of IgG4-related systemic disease. These are frequently associated with elevated serum IgG4 levels. This study aimed to clarify clinical implications of serial changes of elevated serum IgG4 levels in IgG4-related systemic diseases.

METHODS

Serial changes of elevated serum IgG4 levels were examined in patients with IgG4-related systemic diseases. Patients Serial changes of elevated serum IgG4 levels were examined in 44 patients: AIP (n=24), Mikulicz's disease (n=8), pancreatic cancer (n=5), bile duct cancer (n=1), sclerosing cholangitis (n=1), hypereosinophilic syndrome (n=1), chronic thyroiditis (n=1), hypophysitis (n=1), idiopathic pancreatitis (n=1), and Behcet's disease (n=1).

RESULTS

The serum IgG4 levels decreased in all patients with AIP and Mikulicz's disease after steroid therapy. The serum IgG4 levels were normalized in 46% of AIP patients and 38% of Mikulicz's disease patients. The serum IgG4 levels were not normalized at remission in 3 of 4 relapsed AIP patients, and re-elevation of serum IgG4 levels was detected in all relapsed patients. Elevated serum IgG4 levels decreased in 3 patients with pancreatic cancer after resection or chemotherapy, and decreased in patients with hypereosinophilic syndrome, sclerosing cholangitis, and hypophysitis after steroid therapy.

CONCLUSION

Measurement of serial serum IgG4 levels is useful to determine the disease activity of IgG4-related systemic diseases.

Serum IgG4-negative autoimmune pancreatitis

BACKGROUND

Autoimmune pancreatitis (AIP) is considered to be a pancreatic lesion of IgG4-related systemic disease, but about 20% of AIP patients do not have elevated serum IgG4 levels. This study aimed to clarify the pathophysiology of AIP patients without elevated serum IgG4 levels.

METHODS

Fifty-eight AIP patients were divided into 2 groups: those with elevated serum IgG4 levels (>135 mg/dl; SIgG4-positive AIP) and those without (SIgG4-negative AIP). The 2 groups' clinical, serological, radiological, and histological findings, as well as salivary and lacrimal gland function, were compared.

RESULTS

Serum IgG4 levels were elevated in 45 AIP patients and normal in 13 patients. In SIgG4-negative AIP patients, the female ratio tended to be high; obstructive jaundice was less likely; abdominal pain and acute pancreatitis were more likely; segmental swelling of the pancreatic body and/or tail was more common; sclerosing extrapancreatic lesions, salivary and lacrimal gland dysfunction, and abundant infiltration of IgG4-positive plasma cells in the gastric mucosa were less likely; and conservative follow-up was sometimes implemented. Histological examination of the pancreas of SIgG4-negative AIP showed lymphoplasmacytic sclerosing pancreatitis (LPSP) rather confined to the pancreas (n = 4), inadequate material (n = 2), and pancreatic fibrosis showing infiltration of lymphocytes without infiltration of IgG4-positive cells or neutrophils (n = 2).

CONCLUSIONS

Clinicopathological features of SIgG4-negative AIP differed from those of SIgG4-positive AIP. Some SIgG4-negative AIP cases are LPSP rather confined to the pancreas. SIgG4-negative AIP may include idiopathic duct-centric pancreatitis (IDCP) or sclerosing pancreatitis other than LPSP or IDCP, but further studies are needed to clarify this issue.

Clinical analysis of high serum IgE in autoimmune pancreatitis

AIM: To clarify the clinical significance of high serum IgE in autoimmune pancreatitis (AIP).

METHODS: Forty-two AIP patients, whose IgE was measured before steroid treatment, were analyzed. To evaluate the relationship between IgE levels and the disease activity of AIP, we examined (1) Frequency of high IgE (> 170 IU/mL) and concomitant allergic diseases requiring treatment; (2) Correlations between IgG, IgG4, and IgE; (3) Relationship between the presence of extrapancreatic lesions and IgE; (4) Relationship between clinical relapse and IgE in patients treated with steroids, and (5) Transition of IgE before and after steroid treatment.

RESULTS: IgE was elevated in 36/42 (86%) patients. Concomitant allergic disease was observed in seven patients (allergic rhinitis in three, bronchial asthma in three, and urticaria in one). There were no significant correlations between IgG, IgG4, and IgE (r = -0.168 for IgG, and r = -0.188 for IgG4). There was no significant difference in IgE in the patients with and without extrapancreatic lesions (526 ± 531 IU/mL vs 819 ± 768 IU/mL, P = 0.163), with and without clinical relapse (457 ± 346 IU/mL vs 784 ± 786 IU/mL, P = 0.374). There was no significant difference in IgE between before and after steroid treatment (723 ± 744 IU/mL vs 673 ± 660 IU/mL, P = 0.633).

CONCLUSION: Although IgE does not necessarily reflect the disease activity, IgE might be useful for the diagnosis of AIP in an inactive stage.

Eosinophilia and allergic disorders in autoimmune pancreatitis

OBJECTIVES

In autoimmune pancreatitis (AIP), the prevalence, interrelationships, and significance of peripheral eosinophilia, allergic disorders, and eosinophil infiltration in the pancreas remain unclear.

METHODS

From medical records, we obtained data on peripheral eosinophil counts at presentation and follow-up, and clinical diagnoses of allergic disorders in 97 AIP patients (78 type 1 and 19 type 2), which were compared with matched healthy controls. Available pancreatic histologic specimens were graded for eosinophils. Peripheral eosinophilia was defined as counts >0.5×10(9) per liter. We examined nature of and association between these parameters in AIP.

RESULTS

Among 78 type 1 AIP patients (mean age 62±14 years, 77% men), peripheral eosinophilia at presentation was diagnosed in 12% and allergic disorders in 15% (vs. 0 and 4% in controls, P=0.0004 and 0.006, respectively). Allergic disorders were observed in 27 and 11% of type 1 AIP with and without eosinophilia, respectively (P=0.08). Patients with and without peripheral eosinophilia were similar in clinical profile. Moderate-to-severe eosinophil infiltration was present in 67% of pancreas resection specimens and did not correlate with peripheral eosinophilia. Type 2 AIP did not differ from type 1 AIP in any of these parameters.

CONCLUSIONS

Peripheral eosinophilia, allergic disorders, and pancreatic eosinophil infiltration are associated with AIP. Eosinophilia in AIP may not reflect an allergic phenomenon, but appears to be consistent with autoimmune mechanism.

Clinicopathological characteristics of patients with IgG4-related tubulointerstitial nephritis

IgG4-related disease is a recently recognized multi-organ disorder characterized by high levels of serum IgG4 and dense infiltration of IgG4-positive cells into several organs. Although the pancreas was the first organ recognized to be affected by IgG4-related disorder in the syndrome of autoimmune pancreatitis, we present here clinico-pathological features of 23 patients diagnosed as having renal parenchymal lesions. These injuries were associated with a high level of serum IgG4 and abundant IgG4-positive plasma cell infiltration into the renal interstitium with fibrosis. In all patients, tubulointerstitial nephritis was the major finding. Although 14 of the 23 patients did not have any pancreatic lesions, their clinicopathological features were quite uniform and similar to those shown in autoimmune pancreatitis. These included predominance in middle-aged to elderly men, frequent association with IgG4-related conditions in other organs, high levels of serum IgG and IgG4, a high frequency of hypocomplementemia, a high serum IgE level, a patchy and diffuse lesion distribution, a swirling fibrosis in the renal pathology, and a good response to corticosteroids. Thus, we suggest that renal parenchymal lesions actually develop in association with IgG4-related disease, for which we propose the term 'IgG4-related tubulointerstitial nephritis.'

Autoimmune pancreatitis and IgG4-related sclerosing disease

Autoimmune pancreatitis (AIP) is a unique form of pancreatitis in which the pathogenesis is suspected to involve autoimmune mechanisms. AIP sometimes mimics pancreatic cancer in its presentation, but as AIP responds dramatically to steroid therapy, accurate diagnosis is necessary. AIP is currently diagnosed on the basis of a combination of characteristic clinical, serological, morphological and histopathological features. However, its diagnosis remains a clinical challenge and there are no internationally agreed diagnostic criteria. Another type of AIP called 'idiopathic duct-centric chronic pancreatitis' or 'AIP with granulocytic epithelial lesion' has been reported in Western countries. IgG4-related sclerosing disease is a systemic disease in which IgG4-positive plasma cells and T lymphocytes extensively infiltrate various organs. Organs with tissue fibrosis and obliterative phlebitis, such as the pancreas, salivary gland and retroperitoneum, show clinical manifestations; AIP seems to represent one manifestation of IgG4-related sclerosing disease. As a mass is formed in most cases of IgG4-related sclerosing disease, a malignant tumor is frequently suspected on initial presentation. Clinicians should consider IgG4-related sclerosing disease in the differential diagnosis to avoid unnecessary surgery.

Analysis of serum IgG subclasses in Churg-Strauss syndrome--the meaning of elevated serum levels of IgG4

OBJECTIVE

Mikulicz's disease (MD) is characterized by symmetrical and persistent enlargement of the lacrimal and salivary glands. Recently it has been categorized as an 'Ig (immunoglobulin) G4-related disease.' It presents with elevated serum levels of IgG4 and abundant infiltration of IgG4-bearing plasmacytes in involved organs. Allergic symptoms are often observed in patients with IgG4-related disease. On the other hand, allergic diseases are often complicated with Churg-Strauss syndrome (CSS). Here we focused on CSS and analyzed the relation of IgG4 in its pathogenesis.

MATERIALS AND METHODS

We analyzed five patients (2 men and 3 women) with CSS and 51 patients (20 men and 31 women) with MD who presented at Sapporo Medical University Hospital since 2001. We measured the serum concentrations of IgG subclasses in the patients with MD and CSS, and evaluated renal specimens from CSS patients, staining them for anti-IgG4 antibody.

RESULTS

We surprisingly found elevated serum levels of IgG4 not only in MD but also in CSS patients. The renal specimens in CSS patients revealed the infiltration of IgG4-positive plasmacytes.

CONCLUSION

IgG4-bearing plasmacytes may be involved in the pathogenesis of CSS, and it is possible that an allergic reaction plays an important role in the pathogenesis of IgG4-related disease.