title: IgG4-related disease in Italy: clinical features and outcomes of a large cohort of patients.
abstract: OBJECTIVE
  To describe the clinical features, treatment response, and follow-up of a large cohort of Italian patients with immunoglobulin (Ig)G4-related disease (IgG4-RD) referred to a single tertiary care centre.
  
  
  METHODS
  Clinical, laboratory, histological, and imaging features were retrospectively reviewed. IgG4-RD was classified as 'definite' or 'possible' according to international consensus guidelines and comprehensive diagnostic criteria for IgG4-RD. Disease activity was assessed by means of the IgG4-RD Responder Index (IgG4-RD RI).
  
  
  RESULTS
  Forty-one patients (15 females, 26 males) were included in this study: 26 with 'definite' IgG4-RD and 15 with 'possible' IgG4-RD. The median age at diagnosis was 62 years. The median follow-up was 36 months (IQR 24-51). A history of atopy was present in 30% of patients. The pancreas, retroperitoneum, and major salivary glands were the most frequently involved organs. Serum IgG4 levels were elevated in 68% of cases. Thirty-six patients were initially treated with glucocorticoids (GCs) to induce remission. IgG4-RD RI decreased from a median of 7.8 at baseline to 2.9 after 1 month of therapy. Relapse occurred in 19/41 patients (46%) and required additional immunosuppressive drugs to maintain long-term remission. Multiple flares occurred in a minority of patients. A single case of orbital pseudotumour did not respond to medical therapy and underwent surgical debulking.
  
  
  CONCLUSIONS
  IgG4-RD is an elusive inflammatory disease to be considered in the differential diagnosis of isolated or multiple tumefactive lesions. Long-term disease control can be achieved with corticosteroids and immunosuppressive drugs in the majority of cases.
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: C
authors.initials: C
authors.lastname: Campochiaro
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: G A
authors.initials: GA
authors.lastname: Ramirez
authors.affiliation: b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: E P
authors.initials: EP
authors.lastname: Bozzolo
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: M
authors.initials: M
authors.lastname: Lanzillotta
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: A
authors.initials: A
authors.lastname: Berti
authors.affiliation: b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: E
authors.initials: E
authors.lastname: Baldissera
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: L
authors.initials: L
authors.lastname: Dagna
authors.affiliation: b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: L
authors.initials: L
authors.lastname: Praderio
authors.affiliation: b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: R
authors.initials: R
authors.lastname: Scotti
authors.affiliation: b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: M
authors.initials: M
authors.lastname: Tresoldi
authors.affiliation: c Division of Gastroenterology and Gastrointestinal Endoscopy , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: L
authors.initials: L
authors.lastname: Roveri
authors.affiliation: d Pancreas Unit, Department of Surgery , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: A
authors.initials: A
authors.lastname: Mariani
authors.affiliation: e Pathology Unit , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: G
authors.initials: G
authors.lastname: Balzano
authors.affiliation: e Pathology Unit , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: R
authors.initials: R
authors.lastname: Castoldi
authors.affiliation: e Pathology Unit , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: C
authors.initials: C
authors.lastname: Doglioni
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: M G
authors.initials: MG
authors.lastname: Sabbadini
authors.affiliation: a Unit of Medicine and Clinical Immunology , IRCCS San Raffaele Scientific Institute , Milan , Italy.|b Department of Neurology , IRCCS San Raffaele Scientific Institute , Milan , Italy.
authors.forename: E
authors.initials: E
authors.lastname: Della-Torre
mesh_terms: D000368:Aged; D001327:Autoimmune Diseases / Q000150:complications / Q000188:drug therapy / Q000276:immunology*; D015331:Cohort Studies; D065426:Cytoreduction Surgical Procedures; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use*; D006801:Humans; D007074:Immunoglobulin G / Q000276:immunology*; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007558:Italy; D008297:Male; D008875:Middle Aged; D016727:Orbital Pseudotumor / Q000209:etiology / Q000276:immunology / Q000601:surgery; D010195:Pancreatitis / Q000188:drug therapy / Q000209:etiology / Q000276:immunology*; D012008:Recurrence; D012074:Remission Induction; D012187:Retroperitoneal Space; D012189:Retrospective Studies; D012793:Sialadenitis / Q000188:drug therapy / Q000209:etiology / Q000276:immunology*
chemical_list: D005938:Glucocorticoids; D007074:Immunoglobulin G; D007166:Immunosuppressive Agents