Algorithm for the Diagnosis of Scleroderma. Early Systemic Sclerosis: Definitions and diagnostic criteria

Introduction: The term scleroderma derives from the Greek words skleros, which means hard, and derma, which means skin. It refers to an acquired systemic inflammatory disease of the connective tissue -also known as systemic sclerosis (SSc)- characterized by excessive collagen deposition in the skin and the internal organs that results in fibrosis. The typical vascular lesion in SSc leads to narrowing of the vessel lumen, intimal thickening, medial hypotrophy, and adventitial fibrosis of small muscular vessels, collagen deposition in the other matrix components of interstice, and the Raynaud phenomenon secondary to these widespread microvascular abnormalities. All these characteristics lead to a connective tissue re-modeling.
Discussion: Several clinical studies utilize the American Rheumatology Association's 1980 classification. However, these diagnostic criteria are unsatisfactory because they fail to take into consideration part of the disease spectrum. Early-phase SSc is characterized by the Raynaud phenomenon (in 90% of all patients), sclerodactyly, and positivity for SSc-specific autoantibodies (antinuclear antibodies, anti-topoisomerase I antibodies, anti-RNA polymerase I and III antibodies, anti-centromere antibodies, anti-fibrillarin antibodies, anti-PM-SCL antibodies).. It is necessary to reduce delays in the diagnosis of SSc.
Conclusions: Patients with red-flag positivity (Raynaud phenomenon and digital edema) require Phase I SSc screening, which consists in capillaroscopic assessment of possible microvascular abnormalities. The work-up will then focus on inflammatory indices, renal function tests, and internal organ involvement (echocardiography, high-resolution computed tomography of the chest, diffusing capacity of the lungs for carbon monoxide).