Extrinsic allergic alveolitis

Key Features of Extrinsic Allergic Alveolitis (EAA):

Occupational Exposure: Inhalation of organic particles, such as avian proteins, fungal spores, and thermophilic actinomycetes.

1. Farmer’s lung: Spores of Saccharopolyspora rectivirgula.

Symptoms:

. Acute: Shortness of breath, dry cough, and sometimes fever, occurring 4-8 hours after exposure.

. Chronic: Persistent cough and progressive dyspnoea.

Physical Examination:

Diffuse fine crackles on auscultation.

Imaging:

. Chest X-ray: Diffuse micronodular interstitial shadowing, particularly in the upper and mid-zones.

Laboratory Tests:

i. Bronchoalveolar lavage: Lymphocytosis.

ii. Blood tests: Typically, no eosinophilia.