Predicting therapeutic response in IgG4-related disease based on cluster analysis.

To bring the clinical practice of immunoglobulin (Ig)G4-related disease (IgG4-RD) close to personalized medicine, we classified the patient groups and clarified the therapeutic responses of each group. A total of 147 patients enrolled in our registry were classified into four groups by cluster analysis with the software. The therapeutic responses and prognosis of each group were examined. The cluster analysis classified the subjects into four groups: Cluster 1, patients who presented with prominent hypergammaglobulinemia, elevated levels of serum IgG4, and hypocomplementemia; Cluster 2, patients who presented with eosinophilia, elevated concentrations of serum IgG, IgG4, and IgE, and in whom CRP tended to be positive; Cluster 3, patients with younger onset and serum levels of IgG, IgG4, and IgE and peripheral eosinophil counts lower than the other clusters; and Cluster 4, patients with elder onset and low peripheral eosinophil counts. The amounts of glucocorticoid for maintenance treatment were from 5 to 7 mg/d in all groups, but the amounts were significantly greater in Cluster 1 (patients with hypergammaglobulinemia, elevated levels of serum IgG4, and hypocomplementemia) than in Cluster 4 (elder onset patients, relatively low concentrations of peripheral eosinophils). With regard to the use of immunosuppressants and the relapse rate, there were high frequencies in Cluster 1 and Cluster 3 (younger onset patients who presented with mild elevations of serum IgG and IgG4). On the other hand, Cluster 4 showed a low rate of relapse and often could discontinue steroids. The present results suggest that personalized medicine could be provided in IgG4-RD by classifying patients based on their clinical features.

Rare type of pancreatitis as the first presentation of anti-neutrophil cytoplasmic antibody-related vasculitis.

A pancreatic tumor was suspected on the abdominal ultrasound of a 72-year-old man. Abdominal computed tomography showed pancreatic enlargement as well as a diffuse, poorly enhanced area in the pancreas; endoscopic ultrasound-guided fine needle aspiration biopsy and endoscopic retrograde cholangiopancreatography failed to provide a definitive diagnosis. Based on the trend of improvement of the pancreatic enlargement, the treatment plan involved follow-up examinations. Later, he was hospitalized with an alveolar hemorrhage and rapidly progressive glomerulonephritis; he tested positive for myeloperoxidase-anti-neutrophil cytoplasmic antibody (ANCA) and was diagnosed with ANCA-related vasculitis, specifically microscopic polyangiitis. It appears that factors such as thrombus formation caused by the vasculitis in the early stages of ANCA-related vasculitis cause abnormal distribution of the pancreatic blood flow, resulting in non-uniform pancreatitis. Pancreatic lesions in ANCA-related vasculitis are very rare. Only a few cases have been reported previously. Therefore, we report our case and a review of the literature.

A case of angioimmunoblastic T-cell lymphoma with high serum VEGF preceded by RS3PE syndrome.

We report the case of a 76-year-old man diagnosed with angioimmunoblastic T-cell lymphoma (AITL) with high serum vascular endothelial growth factor (VEGF) preceded by Remitting seronegative symmetrical synovitis with pitting edema syndrome. He suffered respiratory discomfort caused by large amounts of pleural effusion. Interestingly, changes in serum VEGF measured over time were similar to changes in pleural effusion. Whether VEGF is related to the pathological condition of AITL is a very important question.

Heat shock protein 90 associates with Toll-like receptors 7/9 and mediates self-nucleic acid recognition in SLE.

Systemic lupus erythematosus (SLE) is a prototype systemic autoimmune disease, and disease activity is associated with serum IFN-α level. Plasmacytoid dendritic cells (pDCs) sense microbial as well as self-nucleic acids by TLRs 7 and 9 and produce a large amount of IFN-α. Here, we show that heat shock protein 90 (Hsp90) associates with and delivers TLR7/9 from the ER to early endosomes for ligand recognition. Inhibition of Hsp90 by various approaches including the use of Hsp90 inhibitor, a geldanamycin derivative, suppressed the Hsp90 association with TLR7/9, which resulted in inhibition of IFN-α production, leading to improvement of SLE symptoms in mice. Notably, we observed that serum Hsp90 is clearly increased in patients with active SLE compared with that in patients with inactive disease. Furthermore, we demonstrated that serum Hsp90 detected in SLE patients binds to self-DNA and/or anti-DNA Ab, thus leading to stimulation of pDCs to produce IFN-α. Our data demonstrate that Hsp90 plays a crucial role in the pathogenesis of SLE and that an Hsp90 inhibitor will therefore provide a new therapeutic approach to SLE and other nucleic acid-related autoimmune diseases.

CCAAT/enhancer binding protein α (C/EBPα)(+) M2 macrophages contribute to fibrosis in IgG4-related disease?

IgG4-related disease (IgG4-RD) is a new disease entity characterized by type 2 helper T (Th2)-dominant inflammation and progressive fibrosis. We found the infiltration of strange cell populations in the fibrotic lesions of submandibular gland specimens obtained from 15 patients with IgG4-RD. These cells expressed CCAAT/enhancer binding protein a (C/EBPα). Many of the cell populations were identified with M2 macrophages. The degrees of infiltration of C/EBPα(+)M2 macrophages and the ratio of fibrotic lesions in the specimens were correlated (r(2) = 0.83, p < 0.01). We also analyzed the expression of C/EBPα in other chronic inflammatory disorders: synovium in rheumatoid arthritis (RA), liver tissue in chronic viral hepatitis, and mucosa in ulcerative colitis. The specimens from RA and chronic viral hepatitis showed infiltration of C/EBPα(+) cells, but there were few C/EBPα-positive cells in ulcerative colitis. Fibrosis is not a major issue in ulcerative colitis. In conclusion, we found the remarkable infiltration of C/EBPα(+)M2 macrophages in cases of chronic inflammation with fibrosis, including IgG4-RD. This primitive study also disclosed that most of C/EBPα(+)M2 macrophages localized in fibrotic lesions, and the degree of the infiltration and the ratio of fibrotic area were correlated.

Identification of relapse predictors in IgG4-related disease using multivariate analysis of clinical data at the first visit and initial treatment.

OBJECTIVES: Inducting clinical remission by glucocorticoid treatment is relatively easy in IgG4-related disease (IgG4-RD), but relapse also occurs easily with tapering of the steroid dose. The present study tried to analyse the cases to extract predictors of relapse present at the diagnosis of IgG4-RD. METHODS: Subjects comprised 79 patients with IgG4-related dacryoadenitis and sialadenitis, known as Mikulicz's disease, who were diagnosed between April 1997 and October 2013 and followed-up for >2 years from the initial induction treatment. They were applied to Cox proportional hazard modelling, based on the outcome of interval to relapse. We performed multivariate analysis for the clinical factors of these cases and identified predictors of relapse. RESULTS: Identified factors were male sex and younger onset in cases without organ involvement at diagnosis and low levels of serum IgG4 in cases with organ dysfunction at diagnosis. Complication with autoimmune pancreatitis and low steroid dose at initial treatment also tended to be associated with recurrence. CONCLUSION: Follow-up is important in cases with recognized risk factors for relapse, including male sex and younger onset in cases without organ damage.

Everyday clinical practice in IgG4-related dacryoadenitis and/or sialadenitis: results from the SMART database.

Abstract Objective. Immunoglobulin (Ig)G4-related disease (IgG4-RD) is a new disease entity that has only been identified this century. Clinical information is thus lacking. We established the Sapporo Medical University and Related Institutes Database for Investigation and Best Treatments of IgG4-related Disease (SMART) to clarify the clinical features of IgG4-RD and provide useful information for clinicians. Methods. Participants comprised 122 patients with IgG4-related dacryoadenitis and/or sialadenitis (IgG4-DS), representing lacrimal and/or salivary lesions of IgG4-RD, followed-up in December 2013. We analyzed the sex ratio, mean age at onset, organ dysfunction, history or complications of malignancy, treatments, rate of clinical remission, and relapse. Results. The sex ratio was roughly equal. Mean age at diagnosis was 59.0 years. Positron emission tomography revealed that the ratio of other organ involvements was 61.4%. Complications of malignancy were observed in 7.4% of cases. Glucocorticoid was used to treat 92.1% of cases, and the mean maintenance dose of prednisolone was 4.8 mg/day. Rituximab was added in three cases, and showed good steroid-sparing effect. The clinical remission rate was 73.8%, and the annual relapse rate was 11.5%. Half of the cases experienced relapses within 7 years of initial treatment. Conclusion. We analyzed the clinical features and treatments of IgG4-DS using SMART, providing useful information for everyday clinical practice.

[Human herpesvirus 6 encephalitis in a patient with glucocorticoid therapy for inflammatory abdominal aortic aneurysm].

A 73-year-old man with inflammatory abdominal aortic aneurysm was admitted with headache and fever. Chest computed tomography (CT) revealed pneumonia and antibiotic therapy was started. Short-term memory impairment was observed and his consciousness had been rapidly deteriorated with seazure. Fluid-attenuated inversion recovery (FLAIR) image and diffusion-weighted magnetic resonance image (DWI) showed high intensity signals around bilateral limbic areas and herpes simplex encephalitis was suspected. After human herpesvirus (HHV)-6 DNA was amplified from cerebrospinal fluid, he was diagnosed with HHV-6 encephalitis and treated with gancyclovir. Clinicians need to be aware that glucocorticoid treatment for elderly can cause HHV-6 encephalitis.

The role of cytotoxic T cells in IgG4-related dacryoadenitis and sialadenitis, the so-called Mikulicz's disease.

OBJECTIVES: Immunoglobulin (Ig) G4-related dacryoadenitis and sialadenitis, the so-called Mikulicz's disease (MD), is a chronic inflammatory disease. However, little is known about its pathogenesis and pathological condition. In the present study, we used immunohistological techniques to compare the roles of cytotoxic T lymphocytes (CTLs) in MD and primary Sjogren's syndrome (SS). We examined the state of CTLs [cytotoxic granule-positive rate and programmed death-1 (PD-1) expression rate] in the salivary glands. METHODS: The study samples comprised 12 submaxillary glands from untreated MD patients and 12 labial glands from SS patients. We performed immunofluorescence and multicolor immunofluorescence to stain CD8, perforin (PRF), granzyme B (GZMB), and PD-1. We measured the total number of CTLs as well as the PRF(+)CTLs, GZMB(+)CTLs, and PD-1(+)CTLs. RESULTS: We found that the degree of infiltration of CTLs was equal in MD and SS, but the rate of CTLs with cytotoxic granules, especially PRF, in MD was less than in SS. In addition, the frequency of PD-1(+)CTLs in MD was higher than that in SS. CONCLUSIONS: Cytotoxic granule-positive CTLs were in the minority in D salivary glands, and this regulation might relate to PD-1 signals like the state of exhaustion and anergy.

Necessity of early intervention for IgG4-related disease--delayed treatment induces fibrosis progression.

OBJECTIVE: Despite ongoing research, the clinical and histopathological natural history of immunoglobulin (Ig) G4-related disease (IgG4-RD) remains unclear and the optimal time to initiate treatment is unknown. A focus on clinical symptoms rather than image finding is recommended for therapeutic initiation in autoimmune pancreatitis, but evidence for this approach is lacking. We aimed to retrospectively analyse disease duration, efficacy of treatment with glucocorticoids and results of histopathological examination of submandibular gland specimens to clarify the necessity for early intervention in IgG4-RD. METHODS: Salivary secretions were assessed before and after treatment in 26 cases of IgG4-related Mikulicz's disease (IgG4-MD). Relationships between disease duration, amount of salivary secretion before treatment, improvement of salivary secretion and ratios of areas of residual acini, fibrosis and lymphoid follicles in the involved submandibular gland specimens were analysed. RESULTS: Salivary secretions were significantly reduced in cases with illness of >2 years (P < 0.05). An inverse correlation was seen between improved amount of salivary secretion and amount of salivary secretion before treatment (r = -0.60). Improved amount of salivary secretion was also associated with each histological factor (acini, r = 0.29; fibrosis, r = -0.23; lymphoid follicles, r = -0.31), which showed interrelationships (acini and lymphoid follicles, r = -0.23; acini and fibrosis, r = 0.42; lymphoid follicles and fibrosis, r = 0.30). CONCLUSION: Salivary secretion can be improved even in cases with lower levels of salivary secretion before treatment in IgG4-RD, but improvements in the amount of salivary secretion decrease with histological changes with delayed therapeutic intervention. These data suggest that early intervention is needed to improve outcomes in patients with IgG4-MD.

Evaluation and Clinical Validity of a New Questionnaire for Mikulicz's Disease.

Objectives. The characteristic features of Mikulicz's disease (MD) are diffuse enlargement of the lacrimal and submandibular glands, elevated levels of serum immunoglobulin (Ig)G4, and abundant infiltration of IgG4-positive plasmacytes into both glands. No disease index is available to properly evaluate MD, so we developed a functional assessment of MD, the Mikulicz's disease activity questionnaire (MAQ), and evaluated its clinical efficacy. Methods. We selected 18 patients who were either being treated for MD or who had presented with recurrence. The patients completed a self-assessment and were scored according to the MAQ sheet during each visit between December 2009 and August 2011. Assessment items were in regard to increases or decreases in lacrimal and salivary gland enlargement and severity of sicca symptoms. Results. On the first visits, MAQ scores were high, but scores decreased rapidly as treatment progressed. When doses of glucocorticoid were reduced, some patients showed increased scores. Dry-symptom scores increased initially. MAQ scores for patients with recurrent MD gradually increased over several months before relapse. However, some patients displayed no elevation in MAQ scores due to relapses at other sites. Conclusion. MAQ score can be used to quantify flares and treatment response and is useful for functional assessment of MD.

[Usefulness of measuring serum IgG4 level as diagnostic and treatment marker in IgG4-related disease].

IgG4-related disease is a chronic disorder, which is characterized with elevated levels of serum immunoglobulin (Ig)G4 and abundant infiltration of IgG4-positive plasmacyte and storiform fibrosis in the enlarged organs. It includes Mikulicz's disease (IgG4-related dacryoadenitis and sialadenitis), autoimmune pancreatitis type I, and so on. In Japan, we have been able to measure the IgG4 levels in our clinic since 2010, and we knew that various diseases except IgG4-related disease, also presented with elevated levels of serum IgG4. Eosinopihic disorders, such as Chrug-Strauss syndrome, a part of rheumatoid arthritis and systemic sclerosis can present with high levels of serum IgG4. So the confusion is seen in some clinicians, but we have to recognize that only serological findings cannot lead to the correct diagnosis in IgG4-related disease. The pathological and image findings also are needed. With regard of the treatments for IgG4-related disease, the levels of serum IgG4 often reflected with the therapeutic response, and were also the markers, which predicted the relapse. We describe herein the significance of measuring serum IgG4 levels in the diagnosis and during the treatment for IgG4-related disease.

Tophaceous gout in the cervical spine.

A 58-year-old woman with a three-year progressive history of chronic arthritis, had become disabled due to general malaise and fever. Her laboratory data revealed hyperuricemia and elevated levels of C-reactive protein. Neither rheumatoid factor nor anti-citrullinated peptide antibodies were present. We diagnosed her with tophaceous gout with uric crystalline revealed by the arthrocentesis of the elbow. (99m)Tc scintigraphy also disclosed a significant uptake in the cervical spine. The CT of the patient's cervical spine revealed significant bone erosion and destruction. We diagnosed the cervical involvement of gout based on the exclusion of infections and sarcoidosis. Rheumatologists should be aware of this rare association.

The immunobiology and clinical characteristics of IgG4 related diseases.

Having the characteristic features of elevated serum IgG4 levels and prominent infiltration of IgG4-positive plasma cells with fibrosis in lesions, Mikulicz's disease (MD) has been recognized as an IgG4-related disease (IgG4-RD). Although incidence of autoimmune pancreatitis (AIP), one of the organ characteristics of IgG4-RD, has been internationally reported, there are only a few such reports of IgG4-related MD. The limited number of reports might be attributable to the low recognition of IgG4-related MD as a clinical entity as well as its misdiagnosis as Sjögren's syndrome (SS). Thus, we compared several clinical features of MD with SS to improve proper clinical diagnosis of MD in the clinical setting. A total of 70 SS and 70 MD cases evaluated at Sapporo Medical University Hospital were retrospectively analyzed. In SS patients, sicca symptoms were the most frequent (87%), followed by articular symptoms (23%), while lacrimal and salivary gland swelling were a rare (10%) and transient manifestation. In contrast, lacrimal or salivary gland swelling was observed in all patients with MD. Although nearly 60% of MD patients complained of sicca syndrome, skin rash and arthralgia were rare symptoms. Hypergammaglobulinemia was recognized in both SS and MD patients, but the occurrence of autoantibodies in patients with IgG4-related MD was low. Extraglandular organ involvement, often involving the retroperitoneum, pancreas, kidney and lung, was often discovered at the time of IgG4-related MD diagnosis. Although corticosteroid therapy tended to delay the hypofunction of salivary gland in SS patients, recovery of decreased function of salivary glands were observed in IgG4-related MD patients. These results suggest the beneficial effect of aggressive corticosteroid intervention in patients with IgG4-related MD. Although SS and MD are both chronic inflammatory diseases affecting the lacrimal and salivary glands, their clinical features and corticosteroid responsiveness are different. Thus, differential diagnosis of these conditions is warranted.

Value of serum IgG4 in the diagnosis of IgG4-related disease and in differentiation from rheumatic diseases and other diseases.

IgG4-related disease (IgG4-RD) is a novel disease entity that includes Mikulicz's disease, autoimmune pancreatitis (AIP), and many other conditions. It is characterized by elevated serum IgG4 levels and abundant IgG4-bearing plasmacyte infiltration of involved organs. We postulated that high levels of serum IgG4 would comprise a useful diagnostic tool, but little information is available about IgG4 in conditions other than IgG4-RD, including rheumatic diseases. Several reports have described cutoff values for serum IgG4 when diagnosing IgG4-RD, but these studies mostly used 135 mg/dL in AIP to differentiate from pancreatic cancer instead of rheumatic and other common diseases. There is no evidence for a cutoff serum IgG4 level of 135 mg/dL for rheumatic diseases and common diseases that are often complicated with rheumatic diseases. The aim of this work was to re-evaluate the usual cutoff serum IgG4 value in AIP (135 mg/dL) that is used to diagnose whole IgG4-RD in the setting of a rheumatic clinic by measuring serum IgG4 levels in IgG4-RD and various disorders. We therefore constructed ROC curves of serum IgG4 levels in 418 patients who attended Sapporo Medical University Hospital due to IgG4-RD and various rheumatic and common disorders. The optimal cut-off value of serum IgG4 for a diagnosis of IgG4-RD was 144 mg/dL, and the sensitivity and specificity were 95.10 and 90.76%, respectively. Levels of serum IgG4 were elevated in IgG4-RD, Churg-Strauss syndrome, multicentric Castleman's disease, eosinophilic disorders, and in some patients with rheumatoid arthritis, systemic sclerosis, chronic hepatitis, and liver cirrhosis. The usual cut-off value of 135 mg/dL in AIP is useful for diagnosing whole IgG4-RD, but high levels of serum IgG4 are sometimes observed in not only IgG4-RD but also other rheumatic and common diseases.

Risk of malignancies in IgG4-related disease.

IgG4-related disease (IgG4-RD) is considered a systemic, chronic, and inflammatory disorder that is characterized by the enlargement of involved organs, elevated levels of IgG4, and abundant infiltration of plasmacytes with IgG4 and fibrosis in involved organs. It is necessary to differentiate IgG4-RD from malignant tumors. Recently we have looked at case reports of IgG4-RD with malignancy that was discovered at systemic screening. In this study, we analyzed the relationship between IgG4-RD and malignancies. The study subjects were 106 patients with IgG4-RD who had been referred to our hospital since April 1997. We analyzed the clinical characteristics of IgG4-RD patients who had cancer that was observed upon the initial diagnosis of IgG4-RD or that occurred during an average follow-up period of 3.1 years. Using data from national cancer registries that monitor cancer incidence in Japan, we evaluated the standardized incidence ratio (SIR) for malignancies in IgG4-RD. Malignancies were observed in 11 of the IgG4-RD patients (10.4%). The malignancies were all different and included lung cancer, colon cancer, and lymphoma. With the exception of the age at which the IgG4-RD diagnosis was made, there were no common features in patients with cancer and those without. The SIR for these malignancies in IgG4-RD was 383.0, which was higher than that for the general population. We should be cognizant of the possible existence of malignancies in patients with IgG4-RD at the time of diagnosis and during follow-up care.