title: Acquired hemophilia A associated with IgG4-related lung disease in a patient with autoimmune pancreatitis.
abstract: Immunoglobulin G4 (IgG4)-related lung diseases can occur in patients with autoimmune pancreatitis (AIP). However, the causal relationship between AIP and acquired hemophilia A (AH) is unknown. We herein report the first case of AH associated with IgG4-related lung disease that developed in a patient with AIP. A 65-year-old asymptomatic man with a history of AIP and sclerosing cholangitis diagnosed at the age of 57 was admitted to our hospital due to an abnormal reticulonodular shadow on chest X-ray. An examination of lung biopsy specimens revealed IgG4-positive plasma cell infiltration in the interstitium. The serum IgG4 level was elevated. One year later, the patient developed a progressive severe hematoma in the left femoral muscle. On admission, laboratory examinations revealed severe anemia with a markedly prolonged activated partial prothrombin time, a decreased level of factor VIII (FVIII) activity, and the existence of anti-FVIII antibodies. These findings were consistent with a diagnosis of AH. No relapse has been observed over the past 25 months, during which time, corticosteroid therapy has been continuously administered.
authors.affiliation: Department of Respiratory Medicine, Toho University Omori Medical Center, Japan. ks142129_ikusou@ybb.ne.jp
authors.forename: Keishi
authors.initials: K
authors.lastname: Sugino
authors.forename: Kyoko
authors.initials: K
authors.lastname: Gocho
authors.forename: Fumiaki
authors.initials: F
authors.lastname: Ishida
authors.forename: Naoshi
authors.initials: N
authors.lastname: Kikuchi
authors.forename: Nao
authors.initials: N
authors.lastname: Hirota
authors.forename: Keita
authors.initials: K
authors.lastname: Sato
authors.forename: Go
authors.initials: G
authors.lastname: Sano
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Isobe
authors.forename: Susumu
authors.initials: S
authors.lastname: Sakamoto
authors.forename: Yujiro
authors.initials: Y
authors.lastname: Takai
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Hata
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Shibuya
authors.forename: Toshimasa
authors.initials: T
authors.lastname: Uekusa
authors.forename: Atsuko
authors.initials: A
authors.lastname: Kurosaki
authors.forename: Sakae
authors.initials: S
authors.lastname: Homma
mesh_terms: D000368:Aged; D001327:Autoimmune Diseases / Q000150:complications* / Q000175:diagnosis / Q000276:immunology*; D006467:Hemophilia A / Q000097:blood / Q000150:complications* / Q000175:diagnosis / Q000276:immunology*; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood / Q000378:metabolism*; D008171:Lung Diseases / Q000150:complications* / Q000175:diagnosis / Q000276:immunology*; D008297:Male; D010195:Pancreatitis / Q000150:complications* / Q000276:immunology*; D010314:Partial Thromboplastin Time
chemical_list: D007074:Immunoglobulin G