Algorithm for diagnosing pulmonary fibrosis in tropical countries.

An algorithm for diagnosis of pulmonary fibrosis in the tropical countries has been developed on the basis of the common causes of fibrosis, and the availability and feasibility of different diagnostic techniques in those countries. First, it is important to exclude common diseases such as the atypical or occult forms of bronchiectasis, pulmonary tuberculosis, and chronic bronchitis, which often overshadow interstitial pulmonary fibrosis. A good history and physical examination supplemented with chest radiography and simple lung function tests are generally enough to narrow down the list of causes of diffuse lung disease to interstitial pulmonary fibrosis. The real difficulty lies in identifying the idiopathic or "lone" forms from the secondary forms of pulmonary fibrosis. High-resolution CT is helpful in a large number of patients. Transbronchial lung biopsy is performed in a select population of patients. Open surgical or thoracoscopy guided biopsy is the gold standard, but is rarely required.