Extensive calcinosis universalis in systemic sclerosis with overlap autoantibodies and severe left ventricular systolic dysfunction: a case report

Systemic sclerosis (SSc) is a chronic autoimmune connective tissue disease characterized by vasculopathy, immune dysregulation, and fibrosis. Calcinosis is recognized in SSc, but extensive calcinosis universalis involving multiple subcutaneous and intramuscular compartments is uncommon. We report a young woman with a systemic sclerosis-predominant phenotype, broad overlap autoantibodies, interstitial lung involvement, and newly diagnosed severe left ventricular systolic dysfunction, emphasizing the distinctive calcinosis phenotype and the diagnostic uncertainty surrounding the cardiac abnormality. A 31-year-old woman presented with acute pulmonary oedema and newly diagnosed heart failure with reduced ejection fraction. Transthoracic echocardiography showed left ventricular dilatation, regional anteroseptal hypokinesia, an LVEF of 30–35%, elevated filling pressures, and a small pericardial effusion. Further history revealed approximately 10 years of progressive skin sclerosis and widespread hard calcified masses. Radiographs and computed tomography demonstrated extensive, widespread calcification involving subcutaneous, periarticular, and intramuscular soft tissues of the thoracoabdominal, pelvic, hip, and knee regions, compatible with calcinosis universalis. Chest CT also showed interstitial lung involvement. Serology showed strong U1-RNP/Sm, anti-Scl-70, anti-Ku, and anti-SSA positivity, with additional anti-dsDNA, anti-Ro52, anti-Sm, and anti-nucleosome reactivity. The phenotype was considered most consistent with systemic sclerosis with overlap serological features; definite MCTD, SLE, and active inflammatory myopathy were not established. The cause of the left ventricular dysfunction remained uncertain. The distinctive feature of this case is the unusually extensive, widespread calcinosis universalis in a young patient with a systemic sclerosis-predominant phenotype and complex overlap serology, occurring alongside newly diagnosed severe left ventricular systolic dysfunction. The cardiac abnormality should not be assumed to be caused by SSc because definitive myocardial characterization and a complete etiological evaluation were unavailable. This case underscores the need to distinguish a serological overlap profile from a clinically established overlap syndrome and to separate unusual phenotype description from unproven causal associations.