Acquired tracheomegaly in adults as a complication of diffuse pulmonary fibrosis

We studied the chest radiographs of 34 consecutive patients with diffuse pulmonary fibrosis to determine the presence of tracheomegaly and to follow its progression with time. Patients had been identified by a computer search of medical records. We measured the internal transverse diameter of the trachea 2 cm above the top of the aortic arch on erect posteroanterior chest radiographs. Transverse diameters greater than 25 mm in men and 21 mm in women were considered indicative of tracheomegaly. Pulmonary-function tests, available in 30 of the 34 patients, showed restrictive lung disease. The transverse tracheal measurements were compared with the cause of fibrosis, severity of restriction, duration of illness, and other clinical variables. Tracheomegaly was present in 10 (29%) of the patients, including four with fibrosing alveolitis, four with sarcoidosis, and two with chronic progressive histoplasmosis. In seven of these patients, serial radiographs showed that the tracheal dilatation had progressed with time. Nine of 24 patients without tracheomegaly also had progressive increase in transverse tracheal diameter over time. Of the 10 patients with tracheomegaly, pulmonary-function tests were available in eight and showed moderate restrictive lung disease in six and severe restrictive lung disease in two. The duration of illness was 3-6 months in two patients, 10-22 years in five patients, and not recorded in three patients. Chronic cough and repeated respiratory infections were slightly more common in those patients with tracheomegaly than in those without. These data suggest that tracheomegaly develops as a complication of diffuse pulmonary fibrosis in patients who have at least moderate restrictive lung disease and prolonged illness, and it may have some association with chronic cough and repeated respiratory infection.