Objective: Juvenile systemic sclerosis (JSSc) is a rare condition in childhood and its variety with no skin involvement, sine scleroderma (ssJSSc), is anecdotal. We report the first case series of patients with ssJSSc. Methods: Demographic, clinical and laboratory data of patients with JSSc followed at our centre were retrospectively collected. Patients with no skin involvement but with all of the features RP, positive ANA, intestinal dysmotility and/or interstitial lung disease (ILD) or pulmonary arterial hypertension (PAH) and/or cardiac or renal involvement typical of scleroderma were defined as having ssJSSc and compared with those with classic JSSc (cJSSc). Results: Among 52 JSSc patients seen in 20 years, five (9.6%) presented with ssJSSc. Their clinical features and those of the only two patients reported in the literature so far were compared with classic JSSc with available complete data. Six patients had cardiac involvement as presenting feature, three primary cardiomyopathy, three secondary to PAH. Two patients died after a brief disease course and one rapidly underwent heart transplantation. In comparison with cJSSc, ssJSSc showed a significantly longer diagnostic delay (20.1 vs 8.3 months, P = 0.017), higher frequency of cardiac involvement (85.7 vs 15.6%, P = 0.001) and worse outcome, intended as mortality or end-stage organ failure rates (42.9% vs 6.2%, P < 0.001). Conclusion: Cardiac involvement represents the most important characteristic of ssJSSc and carries a high morbidity and mortality rate. The longer delay in diagnosis underlines the need for a comprehensive rheumatological work-up in patients with isolated cardiomyopathy or PAH/ILD.
