T Flament1, S Marchand-Adam2, P Gatault3, C Dupin1, P Diot2, L Guilleminault4. 1. CHRU Tours, Service de Pneumologie, F-37044 Tours, France. 2. CHRU Tours, Service de Pneumologie, F-37044 Tours, France; Université François Rabelais, UMR 1100, F-37032 Tours, France; INSERM, Centre d'Etude des Pathologies Respiratoires, UMR 1100/EA6305, F-37032 Tours, France. 3. CHRU Tours, Service de néphrologie, F-37044 Tours, France. 4. CHRU Tours, Service de Pneumologie, F-37044 Tours, France; Université François Rabelais, UMR 1100, F-37032 Tours, France; INSERM, Centre d'Etude des Pathologies Respiratoires, UMR 1100/EA6305, F-37032 Tours, France. Electronic address: laurent.guilleminault@univ-tours.fr.
Abstract
INTRODUCTION: IgG4 has recently been a subject of great interest in human pathology. No data are available about the characteristics of asthma patients with elevated IgG4 levels. POPULATION AND METHODS: An observational study was conducted from January 2006 to March 2015 in a difficult-to-treat population of asthma patients. Twenty-six difficult-to-treat asthma patients with elevated serum IgG4 levels (IgG4/IgG ratio up to 10%) were compared with a control population of 98 difficult-to-treat asthma patients with normal serum IgG4. Blood eosinophilia, total IgE and FeNO were compared between groups to better characterize asthma patients with elevated serum IgG4 levels. RESULTS: Median IgG4 concentrations were 1.72 g/l [1.19-2.36] and 0.22 g/l [0.10-0.49] in the elevated IgG4 group and normal Ig4 group, respectively. Median blood eosinophilia was more than three times higher in patients with elevated serum IgG4 levels than in controls (0.75 10(9)/L [IQR 0.54-1.78] vs 0.22 10(9)/L [IQR 0.09-0.54] respectively, p < 0.0001). Total IgE was twice as high (264.5 kUI/l [IQR 166.3-779] vs 126 kUI/l [IQR 26-350] respectively; p < 0.05) and FeNO was nearly twice as high (61 [IQR 41-111] ppb vs 35 [IQR 23-51] ppb, p < 0.001). Allergic broncho-pulmonary aspergillosis (ABPA) and eosinophilic granulomatosis with polyangiitis (EGPA) were observed in the asthma patients with elevated serum IgG4. Ten patients had unexplained increased blood eosinophilia. CONCLUSION: Asthma patients with elevated IgG4 levels have significantly higher blood eosinophilia, total IgE and FeNO. ABPA and EGPA are observed in patients with elevated serum IgG4.
INTRODUCTION: IgG4 has recently been a subject of great interest in human pathology. No data are available about the characteristics of asthmapatients with elevated IgG4 levels. POPULATION AND METHODS: An observational study was conducted from January 2006 to March 2015 in a difficult-to-treat population of asthmapatients. Twenty-six difficult-to-treat asthmapatients with elevated serum IgG4 levels (IgG4/IgG ratio up to 10%) were compared with a control population of 98 difficult-to-treat asthmapatients with normal serum IgG4. Blood eosinophilia, total IgE and FeNO were compared between groups to better characterize asthmapatients with elevated serum IgG4 levels. RESULTS: Median IgG4 concentrations were 1.72 g/l [1.19-2.36] and 0.22 g/l [0.10-0.49] in the elevated IgG4 group and normal Ig4 group, respectively. Median blood eosinophilia was more than three times higher in patients with elevated serum IgG4 levels than in controls (0.75 10(9)/L [IQR 0.54-1.78] vs 0.22 10(9)/L [IQR 0.09-0.54] respectively, p < 0.0001). Total IgE was twice as high (264.5 kUI/l [IQR 166.3-779] vs 126 kUI/l [IQR 26-350] respectively; p < 0.05) and FeNO was nearly twice as high (61 [IQR 41-111] ppb vs 35 [IQR 23-51] ppb, p < 0.001). Allergic broncho-pulmonary aspergillosis (ABPA) and eosinophilic granulomatosis with polyangiitis (EGPA) were observed in the asthmapatients with elevated serum IgG4. Ten patients had unexplained increased blood eosinophilia. CONCLUSION:Asthmapatients with elevated IgG4 levels have significantly higher blood eosinophilia, total IgE and FeNO. ABPA and EGPA are observed in patients with elevated serum IgG4.
Authors: Stephen M Christensen; Ashton T Belew; Najib M El-Sayed; Wagner L Tafuri; Fernando T Silveira; David M Mosser Journal: PLoS Negl Trop Dis Date: 2019-03-07