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Idiopathic pulmonary fibrosis in patients younger than 50 years.

OBJECTIVE
To assess clinical, radiological, histopathologic, and prognostic differences in younger patients with idiopathic pulmonary fibrosis (IPF).


PATIENTS AND METHODS
This study consisted of patients younger than 50 years with IPF who were seen at the Mayo Clinic in Rochester, Minn, from January 1, 1994, to December 31, 2000. Clinical, radiological, and histopathologic data were abstracted from clinical records. Total lung capacity using plethysmography, vital capacity, diffusing capacity for carbon monoxide using the single-breath method, and alveolar volume using single-breath neon wash-in were measured.


RESULTS
Our study population was composed of 16 men and 6 women with a median age of 45 years (range, 28-49 years). Median survival was 2.1 years, with 1- and 2-year survival rates of 68% and 53%, respectively. Of the 22 patients, 2 were current smokers, 14 were former smokers, and 6 had never smoked. Three patients had familial pulmonary fibrosis, 21 had bibasilar inspiratory crackles, and 10 had digital clubbing. Median total lung capacity was 56.2%, vital capacity was 51.0%, diffusing capacity was 45.5%, and alveolar volume was 65.0%.


CONCLUSION
Although previous studies have suggested that younger age is a favorable prognostic factor in patients with IPF, we found that younger patients have the same poor prognosis as do older patients with this disorder. We observed no distinguishing differences in the clinical, radiological, and histopathologic features compared with those in older patients in whom the disorder is more common. Lung transplantation should be considered early in the treatment of younger patients with IPF.