Sclerosing sialadenitis of the submandibular gland is rarely an immunoglobulin G4-related disease in the Finnish population.

Chronic sclerosing sialadenitis may represent one of many manifestations of an immunoglobulin G4-related disease. However, existing studies typically consist of small patient cohorts rarely conducted in Western populations. The clinical behavior of chronic sclerosing sialadenitis, including follow-up data, warrants further study. Thus, we aimed to determine whether chronic sclerosing sialadenitis always presents as IgG4-related disease or associates with autoimmune diseases and to determine which additional examinations patients may require. Between 2000 and 2017, 51 patients undergoing submandibular gland resection within the Helsinki University Hospital area were diagnosed with chronic sclerosing sialadenitis. We re-evaluated all specimens and performed immunostaining for IgG4. IgG and CD31 stainings were performed for IgG4-positive specimens. IgG4-related disease diagnosis was defined by the Boston consensus statement criteria. We revised clinical data, distributing a follow-up questionnaire to patients to register symptoms of IgG4-related disease or autoimmune disease during follow-up. The chronic sclerosing sialadenitis criteria were fulfilled in 34 patients, whereby 17 were diagnosed as non-sclerosing chronic sialadenitis. In 19 cases, a sialolith associated with a salivary gland lesion. In total, 12 of 51 cases were recognized as IgG4-positive, while two met the criteria for IgG4-related disease. These two cases belonged to the non-sclerosing chronic sialadenitis group, and both involved other organs. The histopathological features between chronic sclerosing sialadenitis and non-sclerosing chronic sialadenitis overlapped regarding the degree of fibrosis and inflammatory infiltrates. In the Finnish population, chronic sclerosing sialadenitis of the submandibular gland does not appear to present as IgG4-related disease. Non-sclerosing chronic sialadenitis can associate with IgG4-related disease. A histopathological distinction between chronic sclerosing sialadenitis and non-sclerosing chronic sialadenitis is not always unequivocal and the presence of a sialolith does not exclude IgG4-positivity. Therefore, immunostaining for IgG4 should be performed when dense plasma cell infiltration is present in either non-sclerosing chronic sialadenitis or chronic sclerosing sialadenitis.

Inducible nitric oxide synthase-mediated injury in a mouse model of acute salivary gland dysfunction.

AIM: Inducible nitric oxide synthase (iNOS) is a key regulator of the innate immune system. The aim of the current study was to explore whether innate immune-mediated iNOS and reactive nitrogen species acutely perturb acinar cell physiology and calcium homeostasis of exocrine salivary tissues. METHODS: Innate immunity in the submandibular gland of C57BL/6 mice was locally activated via intraductal retrograde infusion of polyinosinic:polycytidylic acid (poly (I:C). Expressions of iNOS and the activity of the reactive nitrogen species peroxynitrite, were evaluated by immunohistochemistry. Mice were pre-treated with the selective iNOS inhibitor aminoguanidine in order to substantiate the injurious effect of the nitrosative signal on the key calcium regulator sarcoplasmic/endoplasmic reticulum calcium ATPase (SERCA2b) and calcium signalling. RESULTS: Challenging salivary gland innate immunity with poly (I:C) prompted upregulated expression of iNOS and the generation of peroxynitrite. Inhibition of iNOS/peroxynitrite revealed the role played by upregulated nitrosative signalling in: dysregulated expression of SERCA2b, perturbed calcium homeostasis and loss of saliva secretion. CONCLUSION: iNOS mediates disruption of exocrine calcium signalling causing secretory dysfunction following activation of innate immunity in a novel salivary gland injury model.

Küttner Tumor: IgG4-Related Disease of the Submandibular Gland.

Küttner tumor/chronic sclerosing sialadenitis is a fibroinflammatory process that characteristically involves the submandibular gland of patients with IgG4-related disease. Histologic examination is often important to make the diagnosis because of its nonspecific clinical and radiologic findings. Microscopically, Küttner tumor should be distinguished from other entities such as extranodal marginal zone lymphoma, Sjögren's syndrome, and lymphoepithelial sialadenitis. The lesion is histologically well-demarcated with lobular architecture, extensive fibrosis, marked lymphoplasmacytic inflammation, formation of lymphoid follicles, acinar atrophy, and obliterative phlebitis, without the presence of lymphoepithelial lesions. The IgG4-to-IgG positive plasma cell ratio of >40 % is also an important feature to support the diagnosis of Küttner tumor. Moreover, flow cytometry is helpful to exclude a lymphoproliferative process. Clinicians and pathologists should consider the diagnosis of Küttner tumor in patients with elevated serum IgG4 level. Timely and accurate diagnosis is important for appropriate management.

Chronic sclerosing sialadenitis of the submandibular gland: an entity of IgG4-related sclerosing disease.

Chronic sclerosing sialadenitis typically involves the submandibular gland. It usually occurs in the middle-aged and elderly adults with a slight male predominance. Recent evidences have suggested that it is an entity of IgG4-related sclerosing disease and has distinct histopathological features, such as a dense lymphoplasmacytic infiltrate, sclerosis and obliterative phlebitis. It is important to discriminate this entity from other diseases, trying to give effective treatment to the patients. In this report, we described a patient having chronic sclerosing sialadenitis in the submandibular gland.

Sonographic evaluation of the treatment response in patients with immunoglobulin G4-related disease of the submandibular glands.

OBJECTIVES: To evaluate the usefulness of sonography for monitoring the response to glucocorticoid treatment in patients with immunoglobulin G4 (IgG4)-related disease. METHODS: We conducted a retrospective study using sonography in 12 patients with bilateral swollen submandibular glands who had a diagnosis of IgG4-related disease based on an elevated serum IgG4 level (>135 mg/dL) and histopathologic findings between January 2010 and December 2012. Among these patients, 6 were treated with prednisolone, and the other 6 were placed under observation. B-mode sonographic examinations of the submandibular glands were performed with or without color Doppler imaging at the initial examination and 6 months later. Findings were compared between the groups (treated and untreated), and their relationship with the treatment response of the primarily involved organs was investigated. RESULTS: In the treated group, the submandibular glands of all 6 patients decreased in both size and volume after treatment (average volume ± SD, 27,449.7 ± 24,227.6 to 4609.7 ± 1911.4 mm(3); P = .004). The internal echo texture, characterized by multiple hypoechoic foci scattered against a heterogeneous hyperechoic background of submandibular tissue with demarcated hyperechoic lines, with or without hypoechoic tumor formation, disappeared or was obscured in all cases. In addition, the blood flow signals were reduced in all 3 patients who underwent color Doppler sonography, and the response observed on sonography was found to correlate with the IgG4 level and recovery of specific organ involvement. In contrast, in the untreated group, the submandibular glands showed a tendency to increase in both size and volume (average volume, 9326.3 ± 3054.8 to 12,217.4 ± 4605.5 mm(3); P= .2) without a decrease in the blood flow signals. CONCLUSIONS: Sonography is considered useful for evaluating the response to glucocorticoid therapy in patients with IgG4-related disease of the submandibular glands.

CT features and pathologic characteristics of IgG4-related systemic disease of submandibular gland.

The submandibular gland is one of the most frequently affected salivary gland in IgG4-related systemic disease, usually demonstrate homogeneous attenuation on CT imaging as reported, but without much pathological comparison of many cases. This article is to investigate and analyze the typical CT findings and pathologic characteristics of IgG4-related systemic disease (IgG4-RSD) of submandibular gland. A retrospective analysis of the preoperative CT findings in patients with IgG4-RSD of submandibular glands who underwent surgical resection between January 2010 and February 2014 was performed. Twenty patients (16 women) were identified, with a mean age of 58.1±10.2 years. All patients presented with painless submandibular gland swelling. Diffuse gland enlargement, with clear margins and homogeneous density, was found on non-enhanced CT scans in all cases. There were no calcifications or stones within the involved glands. Based on contrast-enhanced CT appearance the patients could be divided into two groups: 11 cases showed homogeneous gland enhancement; and multiple hyperenhancing foci, with a crazy-paving pattern, were detected in 9 cases, which were in consistent with the pathologic findings. The maximum submandibular gland diameter on transverse images was significantly larger (P=0.008) in patients with crazy-paving appearance (32±4 mm) compared to patients with homogeneous enhancement (28±3 mm). It is concluded that the submandibular glands with IgG4-RSD can be characterized by either homogenous appearance or crazy-paving pattern on contrast-enhanced CT imaging.

Focal autoimmune pancreatitis and chronic sclerosing sialadenitis mimicking pancreatic cancer and neck metastasis.

Type 1 autoimmune pancreatitis (AIP) or chronic sclerosing sialadenitis (Küttner's tumour) is an uncommon disorder that has recently been confirmed as an IgG4-related disease. Here, we describe a rare case of a 53-year-old male patient who primarily presented with pancreatic body mass, left neck mass and several lumps in his lower lip mimicking pancreatic cancer (PC) and neck metastasis. The patient underwent pancreatic body mass and labial gland lumps resection as well as an ultrasound-guided biopsy of the left neck mass. He was diagnosed with IgG4-related focal type of AIP (f-AIP) and Küttner's tumour by immunohistochemistry. The patient responded well to corticosteroid therapy and remains healthy with no signs of recurrence at one year follow-up. The differentiation of f-AIP from PC is very important to avoid unnecessary pancreatic resection.

[Küttner tumour and IgG4-associated sialadenitis as a benign cause of swelling of the submandibular glands].

This is a case report of a 53-year-old man who had a swelling of both submandibular glands and an elevated serum immunoglobulin G (IgG) level. The histopathology examination was positive for IgG4 plasma cells with an IgG4/IgG ratio of 0.62, which is diagnostic for IgG4-associated sialadenitis. If IgG4-associated sialadenitis is suspected fine needle aspiration, serum IgG/IgG4 and examination of extra salivary disease should be performed to confirm the diagnosis.

Clinical features and treatment outcomes of immunoglobulin g4-related sclerosing sialadenitis.

Idiopathic enlargement of salivary glands used to be confusing in diagnosis until immunoglobulin G4 (IgG4)-related sclerosing sialadenitis was proposed as a possible answer. In this case series, we reported the clinical features and management outcomes in 16 patients with IgG4-related sclerosing sialadenitis. We retrospectively studied 16 patients in clinical examination, serology, pathology, and sonography features. All patients were treated by corticosteroids and followed up for at least 3 months. The results of clinical features showed that all of the patients presented persistent, symmetric bilateral swelling of the salivary glands, elevated levels of serum IgG4, and/or IgG4-positive plasmacytes infiltration and tissue fibrosis. The results of all autoantibody tests were negative. The typical sonographic manifestation revealed multiple hypoechoic foci with an irregular netlike diffuse lesion in salivary glands. Most patients showed excellent response to steroids treatment. We conclude that, for patients who present (1) symmetric swelling of bilateral salivary glands for more than 3 months, (2) elevated serum IgG4 level (>135 mg/dL), and (3) enlargement in bilateral salivary glands with multiple hypoechoic areas (irregular netlike appearance) in the sonography, the diagnosis of IgG4-related sclerosing sialadenitis should be considered. A comprehensive understanding of the medical condition and appropriate pathology examination are the key to diagnose. Steroids treatment is effective, and a treatment plan should be set up and followed in the long-term.

T helper 2 and regulatory T-cell cytokine production by mast cells: a key factor in the pathogenesis of IgG4-related disease.

IgG4-related disease is a systemic disorder with unique clinicopathological features and uncertain etiological features and is frequently related to allergic disease. T helper 2 and regulatory T-cell cytokines have been reported to be upregulated in the affected tissues; thus, the production of these cytokines by T helper 2 and regulatory T cells has been suggested as an important factor in the pathogenesis of IgG4-related disease. However, it is not yet clear which cells produce these cytokines in IgG4-related disease, and some aspects of the disorder cannot be completely explained by T-cell-related processes. To address this, we analyzed paraffin-embedded sections of tissues from nine cases of IgG4-related submandibular gland disease, five cases of submandibular sialolithiasis, and six cases of normal submandibular gland in order to identify potential key players in the pathogenesis of IgG4-related disease. Real-time polymerase chain reaction analysis confirmed the significant upregulation of interleukin (IL)4, IL10, and transforming growth factor beta 1 (TGFß1) in IgG4-related disease. Interestingly, immunohistochemical studies indicated the presence of mast cells expressing these cytokines in diseased tissues. In addition, dual immunofluorescence assays identified cells that were double-positive for each cytokine and for KIT, which is expressed by mast cells. In contrast, the distribution of T cells did not correlate with cytokine distribution in affected tissues. We also found that the mast cells were strongly positive for IgE. This observation supports the hypothesis that mast cells are involved in IgG4-related disease, as mast cells are known to be closely related to allergic reactions and are activated in the presence of elevated non-specific IgE levels. In conclusion, our results indicate that mast cells produce T helper 2 and regulatory T-cell cytokines in tissues affected by IgG4-related disease and possibly have an important role in disease pathogenesis.

Function of blood monocytes among patients with orofacial infections.

Few data are available on the significance of the integrity of the innate immune system among patients with orofacial infections. This was assessed in the present study. Peripheral blood mononuclear cells (PBMCs) were isolated from 23 patients with orofacial infections before surgical debridement and from 12 healthy volunteers. PBMCs were stimulated with bacterial endotoxin (LPS) and with Pam3Cys. Concentrations of interleukin (IL)-1ß, IL-6 and tumor necrosis factor-alpha (TNFα) were estimated in supernatants by an enzyme immunoassay. Concentrations of estimated cytokines released from PBMCs of healthy volunteers and of patients did not differ. Intensity of cytokine release after stimulation was related with the time until complete resolution of the infection (p: 0.046). It is concluded that adequate functions of blood monocytes are associated with favorable outcome after surgery for orofacial abscesses. It seems, however, that impairment of monocyte function predisposes to infection persistence.

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.

Unusual involvement of IgG4-related sclerosing disease in lacrimal and submandibular glands and extraocular muscles.

Chronic sclerosing sialadenitis, also known as Kuttner tumor, is a chronic inflammatory disease of the salivary glands that is reported in a few cases in medical literature. Recent reports suggest that certain aspects of sclerosing diseases, including chronic sclerosing sialadenitis or dacryoadenitis, should be classified under immunoglobulin G4 (IgG4)-related sclerosing disease based on immunohistochemical studies. This study reports an unusual case of IgG4-related sclerosing disease appearing simultaneously in the lacrimal glands, submandibular glands, and extraocular muscles. A 56-year-old male presented with complaints of bilateral eyelid swelling and proptosis that began two years ago. Computed tomography confirmed that bilateral submandibular enlargements also existed five years ago in the subject. Orbital computed tomography and magnetic resonance imaging revealed bilateral lacrimal gland enlargement and thickening of extraocular muscles. Typical findings of chronic sclerosing dacryoadenitis were revealed upon pathologic exam of the right lacrimal gland. Immunostaining revealed numerous IgG4-positive plasma cells. Through these clinical features, we make a diagnosis of IgG4-relataed sclerosing disease in the subject.

Involvement of toll-like receptors in autoimmune sialoadenitis of the non-obese diabetic mouse.

The aim of this study was to characterize the expression of Toll-like receptors (TLRs) during the development of sialoadenitis in the non-obese diabetic mouse. Submandibular glands were dissected from non-obese diabetic mice at 4, 8, 10, 12, and 16 weeks of age. The mRNA expression levels of TLR1, 2, 3, 4, 5, 6, 7, 8, 9, 11, 12, 13, MyD88, and TRIF was quantified using real-time reverse transcription polymerase chain reaction. The mRNA expression levels in 4-week-old non-obese diabetic mice were used as controls. The expression levels of TLR1, 2, 4, and 9 were significantly higher at 8, 10, 12, and 16 weeks than the levels in the controls. The expression level of TLR3 was significantly higher at 16 weeks than in the controls. A group of mice were given drinking water containing 4.75% chloroquine starting at 4 weeks. Chloroquine caused a significant decrease in the expression of TLR1, 2, 3, 4, and 9 at 16 weeks compared with control mice who did not receive chloroquine. The areas of lymphocyte infiltration seen on serial sections of submandibular glands in the mice receiving chloroquine were significantly smaller than the areas of infiltration in control glands. Increased expression of Toll-like receptors may be involved in the development and/or progression of sialoadenitis in the non-obese diabetic mouse. Toll-like receptors may be a therapeutic target for autoimmune sialoadenitis.

Sonographic appearance of the submandibular glands in patients with immunoglobulin G4-related disease.

Swelling of the salivary glands is often an initial sign of immunoglobulin G4 (IgG4)-related disease or IgG4-related sclerosing/autoimmune disease. We encountered 2 patients with IgG4-related disease who showed swollen submandibular glands with a unique characteristic sonographic pattern. Bilateral submandibular glands of both patients were enlarged with a smooth contour. The internal echo texture indicated multiple hypoechoic foci scattered against a heterogeneous background, which characteristically appeared with a mottled or irregular netlike appearance. A histopathologic examination of a resected section showed multiple foci of dense infiltrated lymphoplasmacytic cells and lymph follicles encircled by fibrous bands. A mottled appearance in the sonographic findings of the submandibular glands suggests the characteristic of IgG4-related disease and can be helpful in the differential diagnosis at the initial manifestation.

Activation of innate immunity accelerates sialoadenitis in a mouse model for Sjögren's syndrome-like disease.

OBJECTIVE: Sjögren's syndrome is a chronic autoimmune disorder characterized by progressive lymphocytic infiltration within the salivary and lacrimal glands. This study was undertaken to investigate the effects of innate immunity activation on sialoadenitis in a mouse strain genetically susceptible for development of SS-like disease. METHODS: Female New Zealand Black X New Zealand White F1 mice were repeatedly treated with toll-like 3 receptor agonist poly(I:C). Submandibular glands were investigated at different time points for sialoadenitis by immunohistochemistry and for gene expression of different chemokines by quantitative PCR. Submandibular gland-infiltrating cells were characterized by flow cytometry. RESULTS: Poly(I:C) treatment significantly upregulated the expression of multiple chemokines within the submandibular glands. The severity and incidence of sialoadenitis was considerably higher in poly(I:C)-treated mice. There was a preponderance of dendritic cells and NK cells in the initial inflammatory cell infiltrates, and these were followed by CD4+ T cells. CONCLUSIONS: Our data clearly demonstrate that systemic activation of innate immunity accelerates sialoadenitis in a mouse model for SS-like disease. These findings suggest that chronic activation of innate immunity can influence certain features of SS.

Loss of PKCδ results in characteristics of Sjögren's syndrome including salivary gland dysfunction.

OBJECTIVES: Chronic infiltration of lymphocytes into the salivary and lacrimal glands of patients with Sjögren's syndrome (SS) leads to destruction of acinar cells and loss of exocrine function. Protein kinase C-delta (PKCδ) is known to play a critical role in B-cell maintenance. Mice in which the PKCδ gene has been disrupted have a loss of B-cell tolerance, multiple organ lymphocytic infiltration, and altered apoptosis. To determine whether PKCδ contributes to the pathogenesis of SS, we quantified changes in indicators of SS in PKCδ-/- mice as a function of age. Salivary gland histology, function, the presence of autoantibodies, and cytokine expression were examined. MATERIALS AND METHODS: Submandibular glands were examined for the presence of lymphocytic infiltrates, and the type of infiltrating lymphocyte and cytokine deposition was evaluated by immunohistochemistry. Serum samples were tested by autoantibody screening, which was graded by its staining pattern and intensity. Salivary gland function was determined by saliva collection at various ages. RESULTS: PKCδ-/- mice have reduced salivary gland function, B220+ B-cell infiltration, anti-nuclear antibody production, and elevated IFN-γ in the salivary glands as compared to PKCδ+/+ littermates. CONCLUSIONS: PKCδ-/- mice have exocrine gland tissue damage indicative of a SS-like phenotype.

Chronic sclerosing sialadenitis (Küttner tumor) is an IgG4-associated disease.

BACKGROUND: Chronic sclerosing sialadenitis is a fibroinflammatory disease of the salivary glands, characteristically of the submandibular gland. One prior Asian study proposed that chronic sclerosing sialadenitis is a part of the spectrum of IgG4-associated disease. This association has not been confirmed in Western populations. We therefore, investigated the relationship between IgG4 and chronic sclerosing sialadenitis, and compared the histomorphologic features of this condition with those of chronic sialadenitis-not otherwise specified, Sjögren syndrome, and lymphoepithelial sialadenitis. MATERIALS AND METHODS: We evaluated 13 cases of chronic sclerosing sialadenitis and compared them with 15 cases of chronic sialadenitis-not otherwise specified, 8 lip biopsies from individuals with Sjögren syndrome, and 4 cases of lymphoepithelial sialadenitis. Immunohistochemistry for IgG, and IgG4 was carried out. IgG4-positive plasma cells were quantified and the IgG4/IgG ratio was calculated. RESULTS: Seven patients with chronic sclerosing sialadenitis were female and 6 were male. Their mean age was 61 years (range: 27 to 80). Twelve chronic sclerosing sialadenitis cases involved the submandibular gland (bilaterally in 3) and in 1 there was a parotid lesion. Three of these 12 cases had manifestations of IgG4-associated systemic disease. Morphologically these specimens had preservation of lobular architecture, hypercellular interlobular fibrosis, florid lymphoid hyperplasia, and numerous plasma cells. Obliterative phlebitis was observed in 6 cases. The histologic features of chronic sclerosing sialadenitis were reminiscent of autoimmune pancreatitis, and were either not observed or were present only focally in cases of chronic sialadenitis, Sjögren syndrome, and lymphoepithelial sialadenitis.Eleven of 12 evaluable cases showed an increased number of IgG4 plasma cells with a mean of 229/high-power field (HPF) (range 75 to 608) and an overall IgG4/IgG ratio of 0.86 (range 0.5 to 1). The only patient whose biopsy lacked IgG4-positive plasma cells had pathologic evidence of cytomegalovirus infection. Chronic sclerosing sialadenitis cases, in comparison with the other 3 groups studied, showed a significantly higher number of IgG4 positive plasma cells (P<0.05). Patients with chronic sialadenitis-not otherwise specified had a median number of only 16 IgG4-positive plasma cells/HPF (range 2 to 44), with an IgG4/IgG ratio of 0.14 (range 0.02 to 0.28). The Sjögren syndrome patients had a median of 1 IgG4-positive plasma cell/HPF (range 0 to 3), with an IgG4/IgG ratio of 0.02 (range 0 to 0.07). Patients with lymphoepithelial sialadenitis had a median of 0 IgG4-positive plasma cells per HPF. CONCLUSION: Chronic sclerosing sialadenitis has a characteristic morphologic appearance. This morphologic appearance, in conjunction with the elevated IgG4 expression, distinguishes chronic sclerosing sialadenitis from other inflammatory diseases of the salivary glands. Chronic sclerosing sialadenitis belongs to the spectrum of IgG4-related diseases.