title: IgG4-related disease: a case report with duration of more than 16 years and review of literature.
abstract: BACKGROUND
  IgG4-related disease was first reported in 2001 and was officially named in 2010. It is now considered as a systemic disease that might affect any organ system. The characteristic pathological changes of IgG4-related disease are extensive infiltration of IgG4-positive plasma cells. IgG4-related disease is a kind of benign lesions, but there has not been well-defined standard treatment so far. Patients usually respond well to corticosteroids. The prognosis of IgG4-related disease is perhaps good as long as early detection and treatment.
  
  
  METHODS
  We report one case of IgG4-related disease with a 16-years anamnesis with multi-pseudotumor masses. He was diagnosed with chronic kidney disease with wide interstitial renal fibrosis. And he received glucocorticoids therapy. After 2 month therapy, the serum creatinine, erythrocyte sedimentation rate, and serum IgG4 decreased significantly. The discussion includes presentation, clinical course, diagnosis, and prognosis of IgG4-related disease. The case and discussion highlight the importance of diagnosis and the good prognosis of IgG4-related diseases.
  
  
  RESULTS
  Our case highlights the importance of diagnosis and the good prognosis of IgG4-related diseases. IgG4-related disease is a systemic fibro-inflammatory immune-mediated disorder and now recognized in almost every major organs. Characteristics of the disease is multiple lymph nodes and the response to glucocorticoids therapy is well. In such case, he had a history of 16 years with multi-pseudotumor masses and misdiagnosed for 16 years, if the doctors were not awareness of higher serum immunoglobulin G4 (IgG4) than normal, the correct diagnosis may be missed or delayed. Consequently, appropriate treatment for IgG4-related disease would also be delayed or not provided and likely result in increased morbidity and mortality.
  
  
  CONCLUSIONS
  IgG4-related disease is a systemic fibro-inflammatory immune-mediated disorder and progresses slowly. In the present patient the course of IgG4-related disease appears to be benign. The prognosis of IgG4-related disease depend on early diagnosis and treatment.
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Tao
authors.initials: T
authors.lastname: Peng
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Hu
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Xie
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Baodong
authors.initials: B
authors.lastname: Jiang
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Junhui
authors.initials: J
authors.lastname: Zhen
authors.affiliation: Department of Nephrology, Shandong University Qilu Hospital, Jinan, 250012 China.
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Yang
keywords: Chronic kidney disease; Glucocorticoids; IgG4-related disease; Misdiagnosis; Prognosis; Pseudotumor