title: IgG4-related skin disease, a mimic of angiolymphoid hyperplasia with eosinophilia.
abstract: Mikulicz's disease is considered one of the IgG4-related diseases that are characterized by elevated serum IgG4 concentrations and the immunohistochemical finding of IgG4-positive plasma cells. The IgG4-related diseases often exhibit a wide variety of eosinophil infiltration. A 66-year-old male with Mikulicz's disease developed multiple, nonpruritic, red papules on the left opisthotic region 2 years after diagnosis. A biopsy of the skin lesions revealed follicle-like formation in the dermis and subcutaneous tissue containing nodular lymphocytic infiltration with numerous eosinophils and plasma cells, predominately around venules, mimicking angiolymphoid hyperplasia with eosinophilia (ALHE). Immunohistochemically, most IgG-expressing plasma cells were positive for IgG4 (IgG4/IgG ratio = 72%). Our patient appeared to have a condition associated with the IgG4-related diseases. Caution should be exercised in diagnosing skin lesions of the IgG4-related diseases, which are confusingly similar in appearance and histology to ALHE.
authors.affiliation: Department of Dermatology, Kanazawa University Graduate School of Medical Science, Kanazawa, Japan. yasuhito@med.kanazawa-u.ac.jp
authors.forename: Yasuhito
authors.initials: Y
authors.lastname: Hamaguchi
authors.forename: Manabu
authors.initials: M
authors.lastname: Fujimoto
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Matsushita
authors.forename: Seiko
authors.initials: S
authors.lastname: Kitamura-Sawada
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Kawano
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Takehara
mesh_terms: D000368:Aged; D000796:Angiolymphoid Hyperplasia with Eosinophilia / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D001706:Biopsy; D003937:Diagnosis, Differential; D004804:Eosinophils / Q000473:pathology; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis / Q000097:blood*; D007150:Immunohistochemistry; D008297:Male; D008882:Mikulicz' Disease / Q000175:diagnosis / Q000188:drug therapy / Q000473:pathology; D010950:Plasma Cells / Q000473:pathology; D011239:Prednisolone / Q000627:therapeutic use; D012871:Skin Diseases / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology
chemical_list: D005938:Glucocorticoids; D007074:Immunoglobulin G; D011239:Prednisolone