For example, there are particular clinical, physiologic, radiographic, and broncho-scopic features that when present provide a confident diagnosis of IPF without performing a surgical lung biopsy. However, up to 10% of patients with ILD may have normal CXR findings; therefore, a normal CXR finding cannot rule out clinically significant disease. In contrast, with the technical resolution of the current generations of HRCT scans, it is unlikely that a patient with a truly normal scan finding will have clinically significant ILD. The greater problem is whether the radiographic abnormalities identified define a characteristic enough pattern to provide a diagnosis. canadian health & care mall
As most patterns are not diagnostic, a significant number of patients will require bronchoscopy (with endobronchial/transbronchial biopsy and/or BAL) and/or surgical lung biopsy for a definitive diagnosis. Also, as the common causes of cough occur commonly, explanations other than the diagnosis of ILD should always be considered before ascribing a specific cause for the cough. A recent review of the causes of chronic cough in patients with ILD at a center with a validated systematic diagnostic protocol has suggested that the cause of cough may be due to a diagnosis other than ILD at least 50% of the time. Also as part of their clinical syndrome, some cases of ILD may be specifically associated with one or more of the common causes such as chronic sinus disease and other upper airway abnormalities (eg, Wegener granulomatosis), gastroesophageal reflux (eg, scleroderma), or reactive airways disease (eg, chronic eosinophilic pneumonia). Therefore, a diagnosis of ILD as the sole cause of cough should be considered a diagnosis of exclusion.
No formal treatment trial in IPF has used reduction in cough as an end point. However, one small prospective controlled study in nonsmoking IPF patients without reversible airflow limitation, chronic rhinitis, or gastroesophageal reflux disease (GERD) showed that treatment with oral corticosteroids decreased cough severity and sensitivity to capsaicin and substance P in all patients.