Hypersensitivity Pneumonitis

Establish a interstitial lung disease (ILD) registry and biorepository to lead towards a further understanding of the disease.

The central hypothesis is that a peer coach-delivered intervention that includes cognitive behavioral principles combined with theory-driven patient education will improve health-related quality of life (HRQOL) of patients with hypersensitivity pneumonitis (HP). The goal of this behavioral and educational intervention, RISE-HP, is to improve health-related quality of life in people who have hypersensitivity pneumonitis and assess feasibility and accessibility of this intervention. Patients with hypersensitivity pneumonitis (HP) experience uncertainty, feelings of anxiety and depression, and marked disruption to their lifestyle and home environment. Poor health-related quality of life (HRQOL) in HP is also driven in part by patients' profound lack of knowledge about the disease. Existing interventions for patients with HP do not target improvement in quality of life. Participants will complete either RISE-HP, a 10-session peer coach delivered behavioral and educational intervention to improve HRQOL in HP, or Staying Well, a 10-session general health education program.

Dyspnea (i.e. breathlessness) and exercise intolerance are common symptoms for patients with interstitial lung disease (ILD), yet it is not known why. It has been suggested that muscle dysfunction may contribute to dyspnea and exercise intolerance in ILD. Our study aims to: i) examine differences in the structure and function of the leg muscles in ILD patients, ii) determine if leg muscle fatigue contributes to dyspnea and exercise limitation in patients with ILD, and iii) determine the effects of breathing extra oxygen on leg muscle fatigue, as well as ability to exercise in ILD patients.

Hypersensitivity Pneumonitis (HP) is an immune-mediated disease that manifests as interstitial lung disease after exposure to an inhaled antigen, often unidentified. HP can be classified as non-fibrotic or fibrotic HP. Fibrotic HP is associated with impaired quality of life (QoL) and reduced survival. The value and decline of forced vital capacity (FVC) are predictive factors of mortality in fibrotic HP. In most expert centres worldwide, corticosteroids are chosen as the first-line drug to treat fibrotic HP in clinical practice. However, this strategy has not been validated in a randomized controlled trial and it remains controversial, Moreover, corticosteroids are responsible for potentially serious adverse events. The hypothesis is that prednisolone, as a first-line treatment in fibrotic hypersensitivity pneumonitis (HP), slows down FVC decline compared to placebo. The main objective is to assess the efficacy of first-line treatment with prednisolone against placebo, on the 6-month change in FVC in percent of predicted value (% pred).The primary endpoint will be the absolute change in FVC (% pred) from baseline (inclusion visit,M0) to 6 months (M6) will be compared between the placebo arm and the prednisolone arm.

Sub-study of the main Pulmonary Fibrosis Biomarker (PFBIO) cohort (NCT02755441), recruiting patients with an MDT-diagnosis of hypersensitivity pneumonitis (HP). Patients are included for the collection of blood samples and regular clinical data. The database and biobank will be available for studies of HP, and can be directly compared to the main PFBIO cohort, which has recruited patients with Idiopathic pulmonary Fibrosis (IPF) since 2016. Biomarkers will be assessed as diagnostic and prognostic. Further subtyping of HP, based on blood markers (including precipitins) will also be possible with the PFBIO-HP project.

Hypersensitivity pneumonitis (HP) is a diffuse infiltrative pneumonitis (DIP) of immuno-allergic origin, caused by exposure to one or more antigenic substances of organic origin, in genetically predisposed individuals. It can take a fibrosing form, eventually leading to chronic respiratory failure. Diagnosis is based on a combination of clinical, biological, CT scan and histological evidence, and is made during multidisciplinary discussions (MDD) of diffuse interstitial lung disease. The antigens responsible, of domestic or professional origin, may be micro-organisms, animal proteins or chemical agents. However, the antigen remains unknown in almost 50% of cases. Lack of antigen identification is an independent risk factor for death in patients with fibrosing HP. In fibrosing forms, corticosteroid therapy does not appear to improve functional prognosis, and ninedanib, an antifibrosing treatment offered in progressive forms, only slows functional decline. Identifying the causative antigen is therefore an essential element in the overall management of these patients, with the aim of implementing avoidance measures. A medical exposure questionnaire has been translated into French to help physicians identify the antigen. The serum precipitin assay is a tool developed to help identify sensitization to an antigen. It is all the more useful when investigations are targeted at the patient's suspected exposure. However, their sensitivity and specificity are variable. The activity of the indoor environment medical advisor (CMEI) has developed in the care of patients with chronic respiratory or allergic pathologies. Their role is to carry out an audit of the dwelling, take environmental measurements to assess the health risk, inform patients about appropriate eviction measures and, in some cases, refer patients to organizations specializing in home improvement. The CMEI visits the patient's home. The environmental audit includes a rigorous macroscopic examination and microbiological swabs of visible anomalies. The CMEI can also supplement its analysis with electrostatic dust collectors, which are left in the home for 4 weeks, enabling both qualitative and quantitative characterization of antigens. To date, no study has prospectively evaluated the contribution of CMEI to antigen identification in patients with fibrosing HP. At the Nantes University Hospital and Angers University Hospital, the environmental audit carried out by the CMEI is an integral part of routine patient management in the event of a HP diagnosis. The main objective of this study is to measure the diagnostic contribution of the indoor environment medical advisor in the identification of antigens responsible for respiratory pathology in patients with fibrosing HP.