title: Comparison of clinical and pathological features of lung lesions of systemic IgG4-related disease and idiopathic multicentric Castleman's disease.
abstract: OBJECTIVE
  The lung lesion [immunoglobulin (Ig)G4-L] of IgG4-related disease (IgG4-RD) is a condition that occurs together with IgG4-RD and often mimics the lung lesion [idiopathic multicentric Castleman's disease (iMCD-L)] of idiopathic multicentric Castleman's disease (iMCD). Because no clinical and pathological studies had previously compared features of these diseases, we undertook this comparison with clinical and histological data.
  
  
  RESULTS
  Nine patients had IgG4-L (high levels of serum IgG4 and of IgG4+cells in lung specimens; typical extrapulmonary manifestations). Fifteen patients had iMCD-L (polyclonal hyperimmunoglobulinaemia, elevated serum interleukin-6 levels and polylymphadenopathy with typical lymphadenopathic lesions). Mean values for age, serum haemoglobin levels and IgG4/IgG ratios were higher in the IgG4-L group and C-reactive protein levels were higher in the iMCD-L group. All IgG4-RD lung lesions showed myxomatous granulation-like fibrosis (active fibrosis), with infiltration of lymphoplasmacytes and scattered eosinophils within the perilymphatic stromal area, such as interlobular septa and pleura with obstructive vasculitis. All 15 lung lesions of iMCD, however, had marked accumulation of polyclonal lymphoplasmacytes in lesions with lymphoid follicles and dense fibrosis, mainly in the alveolar area adjacent to interlobular septa and pleura without obstructive vasculitis.
  
  
  CONCLUSIONS
  Although both lesions had lymphoplasmacytic infiltration, lung lesions of IgG4-RD were characterized by active fibrosis with eosinophilic infiltration within the perilymphatic stromal area with obstructive vasculitis, whereas lung lesions of iMCD had lymphoplasmacyte proliferating lesions mainly in the alveolar area adjacent to the perilymphatic stromal area. These clinicopathological features may help to differentiate the two diseases.
authors.affiliation: Department of Analytic Human Pathology, Nippon Medical School, Tokyo, Japan.
authors.forename: Yasuhiro
authors.identifier: http://orcid.org/0000-0003-4495-7982
authors.initials: Y
authors.lastname: Terasaki
authors.affiliation: Department of Respiratory Medicine, Japanese Red Cross Medical Center, Tokyo, Japan.
authors.forename: Soichiro
authors.initials: S
authors.lastname: Ikushima
authors.affiliation: Health Administration Center, University of Toyama, Toyama, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Matsui
authors.affiliation: Division of Clinical Pathology, NHO Tokyo National Hospital, Tokyo, Japan.
authors.forename: Akira
authors.initials: A
authors.lastname: Hebisawa
authors.affiliation: Department of Respirology, Graduate School of Medicine, Chiba University, Chiba, Japan.
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Ichimura
authors.affiliation: Department of Respiratory Medicine, National Center for Global Health and Medicine, Tokyo, Japan.
authors.forename: Shinyu
authors.initials: S
authors.lastname: Izumi
authors.affiliation: Department of Radiology, Nishigunma National Hospital, Shibukawa, Japan.
authors.forename: Masuo
authors.initials: M
authors.lastname: Ujita
authors.affiliation: Department of Respiratory Medicine, Kurashiki Central Hospital, Kurashiki, Japan.
authors.forename: Machiko
authors.initials: M
authors.lastname: Arita
authors.affiliation: Department of Respiratory Medicine, Kobe City Medical Center General Hospital, Kobe, Japan.
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tomii
authors.affiliation: Department of Respiratory Medicine, St. Marianna University School of Medicine, Yokohama City Seibu Hospital, Yokohama, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Komase
authors.affiliation: Department of Respiratory Medicine, National Hospital Organization Okinawa National Hospital, Ginowan, Okinawa, Japan.
authors.forename: Isoko
authors.initials: I
authors.lastname: Owan
authors.affiliation: Department of Respiratory Medicine, National Hospital Organization Himeji Medical Center, Hyogo, Japan.
authors.forename: Tetsuji
authors.initials: T
authors.lastname: Kawamura
authors.affiliation: Department of Respiratory Medicine, Toho University Medical Center-Sakura Hospital, Chiba, Japan.
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Matsuzawa
authors.affiliation: Department of Molecular Regulation for Intractable Diseases, Institute of Medical Science, Tokyo Medical University, Osaka, Japan.|Osaka Rheumatology Clinic, Osaka, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Murakami
authors.affiliation: Department of Respiratory Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Ishimoto
authors.affiliation: Department of Respiratory Medicine, Nara Medical University, Nara, Japan.
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kimura
authors.affiliation: Department of Respiratory Medicine, Jichi Medical University, Shimotsuke, Tochigi, Japan.
authors.forename: Masashi
authors.initials: M
authors.lastname: Bando
authors.affiliation: Department of Molecular Regulation for Intractable Diseases, Institute of Medical Science, Tokyo Medical University, Osaka, Japan.|Osaka Rheumatology Clinic, Osaka, Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Nishimoto
authors.affiliation: Division of Diagnostic Pathology, Saitama Prefectural Cardiovascular and Respiratory Center, Saitama, Japan.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Kawabata
authors.affiliation: Department of Analytic Human Pathology, Nippon Medical School, Tokyo, Japan.
authors.forename: Yuh
authors.initials: Y
authors.lastname: Fukuda
authors.affiliation: Division of Respiratory Medicine, Kanagawa Cardiovascular and Respiratory Center, Yokohama, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ogura
mesh_terms: D000328:Adult; D000368:Aged; D005871:Castleman Disease / Q000473:pathology*; D005260:Female; D006801:Humans; D007074:Immunoglobulin G; D008171:Lung Diseases / Q000473:pathology*; D008297:Male; D008875:Middle Aged
chemical_list: D007074:Immunoglobulin G
keywords: IgG4-related disease; clinicopathological features; idiopathic multicentric Castleman's disease; lung lesions; lymphoplasmacyte proliferating disease