Retrospective evaluation of our cohort of patients with chronic estrinsic allergic alveolitis

Hypersensitivity pneumonitis (HP) is an interstitial lung disease caused by exposure to organic antigens that cause an immune response mediated by T lymphocytes in susceptible subjects. There is an acute/subacute variant and a chronic variant characterized by fibrotic evolution (cHP). We evaluated functional progression in cHP patients, with a monocentric retrospective observational study. We enrolled 66 patients (14 woman) with an average age at diagnosis of 69 years with a median follow up of 56 months. Diagnosis has been made through multidisciplinary evaluation. Hospitalizations for respiratory causes was 1.6 times per patient. Of the 66 patients, 16 died, 4.2 years after diagnosis. Bronchoscopy: on average, BAL at Neutrophils 8.01%, Lymphocytes 22.02%, Macrophages 64.39%, Eosinophils 2.05%, Basophils 0.00%, and a CD4 / CD8 ratio of 1.53. Chest CT scan: the prevalent lesion in patients was honeycombing (59/66), followed by micronodules (45/66), air trapping (44/66) and traction bronchiectasis (34/66). cHP represents a severe disease, with poor prognosis that can worse in the short/medium term from diagnosis.