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Kazunori Yamada

Other affiliations: University of Geneva
Bio: Kazunori Yamada is an academic researcher from Kanazawa University. The author has contributed to research in topics: Kidney disease & IgG4-related disease. The author has an hindex of 21, co-authored 77 publications receiving 2277 citations. Previous affiliations of Kazunori Yamada include University of Geneva.


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Journal ArticleDOI
TL;DR: AIPC is a unique inflammatory disorder characterized by an immune reaction predominantly mediated by Th2 cells and Tregs, which could be characterized by the over‐production of T helper (Th) 2 and regulatory cytokines.

591 citations

Journal ArticleDOI
TL;DR: There are considerable clinical and pathological differences between IgG4+MOLPS and SS, and based on the clinical features and good response to glucocorticoids, a new clinical entity is proposed: IgG 4+MolPS.
Abstract: Background: Mikulicz’s disease (MD) has been considered as one manifestation of Sjogren’s syndrome (SS). Recently, it has also been considered as an IgG 4 -related disorder. Objective: To determine the differences between IgG 4 -related disorders including MD and SS. Methods: A study was undertaken to investigate patients with MD and IgG 4 -related disorders registered in Japan and to set up provisional criteria for the new clinical entity IgG 4 -positive multiorgan lymphoproliferative syndrome (IgG 4 +MOLPS). The preliminary diagnostic criteria include raised serum levels of IgG 4 (>135 mg/dl) and infiltration of IgG 4 + plasma cells in the tissue (IgG 4 +/IgG+ plasma cells >50%) with fibrosis or sclerosis. The clinical features, laboratory data and pathologies of 64 patients with IgG 4 +MOLPS and 31 patients with typical SS were compared. Results: The incidence of xerostomia, xerophthalmia and arthralgia, rheumatoid factor and antinuclear, antiSS-A/Ro and antiSS-B/La antibodies was significantly lower in patients with IgG 4 +MOLPS than in those with typical SS. Allergic rhinitis and autoimmune pancreatitis were significantly more frequent and total IgG, IgG 2 , IgG 4 and IgE levels were significantly increased in IgG 4 +MOLPS. Histological specimens from patients with IgG 4 +MOLPS revealed marked IgG 4 + plasma cell infiltration. Many patients with IgG 4 +MOLPS had lymphocytic follicle formation, but lymphoepithelial lesions were rare. Few IgG 4 + cells were seen in the tissue of patients with typical SS. Thirty-eight patients with IgG 4 +MOLPS treated with glucocorticoids showed marked clinical improvement. Conclusion: Despite similarities in the involved organs, there are considerable clinical and pathological differences between IgG 4 +MOLPS and SS. Based on the clinical features and good response to glucocorticoids, we propose a new clinical entity: IgG 4 +MOLPS.

544 citations

Journal ArticleDOI
TL;DR: Although a recent unanimous consensus of all relevant researchers in Japan recently established the diagnostic criteria for IgG4-related disease, findings such as the authors' indicate that further discussion is needed.
Abstract: IgG4-related disease is a new disease classification established in Japan in the 21st century. Patients with IgG4-related disease display hyper-IgG4-gammaglobulinemia, massive infiltration of IgG4

134 citations

Journal ArticleDOI
TL;DR: The serum CRP level is generally low and the serum IgG4 level is elevated in most Japanese IgG 4-RD patients, in contrast to western patients, suggest that these two parameters in IgG3-RD differ in some interesting ways from those hitherto reported in western populations.
Abstract: The aim was to further characterize immunoglobulin G4-related disease (IgG4-RD) by a large-scale multicenter study of its clinical and laboratory features conducted by multidisciplinary physicians of IgG4-RD in Japan. Various specialists retrospectively evaluated IgG4-RD patients diagnosed between 1996 and 2015 in five hospitals by analyzing their baseline clinical features, laboratory, imaging, and pathological test findings, and treatment. Of the 334 patients listed, 205 were male and median age at diagnosis was 65 years. The mean number of organs involved was 3.2 at diagnosis. The most frequently affected organs were the salivary glands, followed by the lacrimal glands, lymph nodes, pancreas, retroperitoneum/periaorta, kidneys, and lungs. The mean serum level of IgG4 was 755 mg/dl, and more than 95% of patients had elevated serum IgG4 levels. The median serum level of C-reactive protein (CRP) was 0.1 mg/dl and the level was less than 1 mg/dl in 90% of patients. A total of 34.7% of patients had low serum levels of C3. Serum levels of C3 and non-IgG4 IgG, calculated as the total IgG minus IgG4, showed an inverse correlation in patients with kidney lesions, while serum IgG4 levels were not correlated with serum C3 levels. Corticosteroid was administered in 78.0% of patients, and was effective in all. The serum CRP level is generally low and the serum IgG4 level is elevated in most Japanese IgG4-RD patients, in contrast to western patients. These original findings suggest that these two parameters in IgG4-RD differ in some interesting ways from those hitherto reported in western populations. Additional studies, especially international comparative ones, are needed to elucidate the extent and significance of these differences between populations. Attention will also have to be paid to whether the existence of such differences requires consideration when devising international classification criteria.

87 citations


Cited by
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Journal ArticleDOI
TL;DR: This statement proposes a terminology scheme for the diagnosis of IgG4-related disease that is based primarily on the morphological appearance on biopsy, and advocates the use of strict criteria for accepting newly proposed entities or sites as components of the IgG 4- related disease spectrum.

2,041 citations

Journal ArticleDOI

1,948 citations

Journal ArticleDOI
TL;DR: The comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists and have increased the sensitivity of diagnosis to 100% for Igg4-related MD, KD, and AIP.
Abstract: IgG4-related disease (IgG4-RD) is a novel clinical disease entity characterized by elevated serum IgG4 concentration and tumefaction or tissue infiltration by IgG4+ plasma cells Although IgG4-RD is not rare and is clinically important, its clinical diagnostic criteria have not been established Comprehensive diagnostic criteria for IgG4-RD, including the involvement of various organs, are intended for the practical use of general physicians and nonspecialists Two IgG4-RD study groups, the Umehara and Okazaki teams, were organized by the Ministry of Health, Labor and Welfare Japan As IgG4-RD comprises a wide variety of diseases, these groups consist of physicians and researchers in various disciplines, including rheumatology, hematology, gastroenterology, nephrology, pulmonology, ophthalmology, odontology, pathology, statistics, and basic and molecular immunology throughout Japan, with 66 and 56 members of the Umehara and Okazaki teams, respectively Collaborations of the two study groups involved detailed analyses of clinical symptoms, laboratory results, and biopsy specimens of patients with IgG4-RD, resulting in the establishment of comprehensive diagnostic criteria for IgG4-RD Although many patients with IgG4-RD have lesions in several organs, either synchronously or metachronously, and the pathological features of each organ differ, consensus has been reached on two diagnostic criteria for IgG4RD: (1) serum IgG4 concentration >135 mg/dl, and (2) >40% of IgG+ plasma cells being IgG4+ and >10 cells/high powered field of biopsy sample Although the comprehensive diagnostic criteria are not sufficiently sensitive for the diagnosis of type 1 IgG4-related autoimmune pancreatitis (IgG4-related AIP), they are adequately sensitive for IgG4-related Mikulicz’s disease (MD) and kidney disease (KD) In addition, the comprehensive diagnostic criteria, combined with organ-specific diagnostic criteria, have increased the sensitivity of diagnosis to 100% for IgG4-related MD, KD, and AIP Our comprehensive diagnostic criteria for IgG4-RD are practically useful for general physicians and nonspecialists

1,417 citations

Journal Article
TL;DR: The clinical care for patients with cholestatic liver diseases has advanced considerably during recent decades thanks to growing insight into pathophysiological mechanisms and remarkable methodological and technical developments in diagnostic procedures as well as therapeutic and preventive approaches.

1,405 citations

Journal ArticleDOI
TL;DR: New classification criteria for Sjögren's syndrome are proposed, which are needed considering the emergence of biologic agents as potential treatments and their associated comorbidity.
Abstract: Objectives We propose new classification criteria for Sjogren’s Syndrome (SS), which are needed considering the emergence of biological agents as potential treatments and their associated co-morbidity. These criteria target individuals with signs/symptoms suggestive of SS.

1,147 citations