Extrinsic allergic alveolitis

Bronchial casts attributed to the use of pegylated interferon and ribavirin

We report the case of a 50-year-old male patient with a rare profile: bronchial casts associated with the use of pegylated interferon and ribavirin. The patient sought treatment in a pulmonology clinic with a history of progressive dyspnea for four months that had evolved to progressive cough followed by frequent and abundant elimination of bronchial casts. The patient was initially treated with bronchodilators, as well as with oral and inhaled corticosteroids. Fiberoptic bronchoscopy, bronchoalveolar lavage and sputum analysis were carried out but did not contribute to the elucidation of the diagnosis. The symptoms developed while the patient was receiving pegylated interferon and ribavirin for the treatment of hepatitis C. The symptoms resolved 30 days after the discontinuation of the treatment. To our knowledge, this is the first report of bronchial casts caused by the use of pegylated interferon and ribavirin.

Extrinsic allergic alveolitis: problems in diagnosis and a potential use for computed tomography

Bird fancier's lung, the most common form of extrinsic allergic alveolitis in Britain, can be a difficult diagnostic problem. The symptoms are non-specific, often insidious in onset and frequently misdiagnosed as influenza or a viral or bacterial pneumonia. Frequently there is a delay in eliciting the history of exposure to the antigen. The chest radiograph is often less impressive than the clinical presentation and may be normal despite severe symptoms, impaired respiratory function and florid pathological changes. We present three cases demonstrating these diagnostic problem. In two cases, high resolution computed tomography demonstrated the typical 'ground glass' opacification seen in active alveolitis. This allowed targeting of transbronchial biopsies which revealed an inflammatory infiltrate of the interstitium with granuloma formation and inflammatory cells in some alveoli. The problems in diagnosis and the potential role of high resolution computed tomography are discussed.