Hypersensitivity pneumonitis (HP) is a complex immune mediated disorders caused by repeated inhalation of and sensitization to wide range of antigens including organic particles and chemical compounds, leading to exaggerated immuneresponse. Hypersenstivity pneumonitis is a common form of diffuse parenchymal lung diseases in Egypt .Pulmonary hypertension has been found as a complication of a number of diseases affecting the lung interstitium, including hypersensitivity pneumonitis, with subsequent affection of the life expectancy Rationale of the study: to find predictors for the development of pulmonary hypertension in patients with hypersensitivity pneumonitis

Cross sectional study included 60 patients with established diagnosis of HP , work up includes history of exposure, clinical examination, HRCT chest, ABGs,6MWD, desaturation degree , spirometry, echocardiography and right heart catheter in patients with high echo probability of PH.

Inclusion Criteria:

• All patients with confirmed diagnosis of Hypersensitivity pneumonitis

Exclusion Criteria:

• Other interstitial lung diseases