Systemic sclerosis sine scleroderma can present in some patients as pulmonary interstitial fibrosis. Until now ten cases with this particular clinical variant, all men, have been reported in the literature. The knowledge of systemic sclerosis sine scleroderma presenting as lung interstitial involvement is important in clinical practice for an early diagnosis and correct therapeutic strategy. This work reports the clinico-serological features of two further cases, one a woman, of systemic sclerosis sine scleroderma with prevalent lung involvement, and describes the effects of therapeutic plasma exchange.