Olson D S, Kumar U N, Funahashi A
Postgrad Med. 1978 Jul;64(1):173-5. doi: 10.1080/00325481.1978.11714885.
Pulmonary involvement usually is a late manifestation of progressive systemic sclerosis. In the case reported here, dyspnea and pulmonary interstitial fibrosis developed more than a year prior to onset of skin and vascular changes. Open-lung biopsy performed early in the course of the disease failed to yield a definitive diagnosis.