Long-term therapy with plasma exchange in systemic sclerosis: effects on laboratory markers reflecting disease activity

Plasma exchange (PEX) is a technique that has been applied to the treatment of many immunological disorders, including connective tissue diseases. The crucial role of some humoral factors in the pathogenesis of systemic scler osis (SSc) could explain the good clinical results obtained in terms of slo wing down the disease progression, but the efficacy of PEX in the treatment of SSc is not yet well defined, owing to the lack of controlled studies an d validated parameters of disease activity. To demonstrate the long-term efficacy of PEX in the treatment of SSc we tre ated a group of 28 SSc patients affected with recent onset and/or rapidly p rogressive disease. Most of these had a diffuse form of SSc, with anti-Sc17 0 antibody as a disease marker. Before and after long-term PEX treatment we evaluated disease activity para meters including the serum levels of interleukin 2 soluble receptor (sIL-2R ) and aminoterminal type III procollagen peptide (PIIINP), plus the percent age of DR+ T cells in the peripheral blood. We also assessed clinical param eters of total skin score and total visceral score. The same parameters wer e evaluated in 25 SSc patients who did not satisfy the admission criteria f or PEX, treated longterm with drugs only. At baseline, serum PIIINP and sIL-2R levels and the percentage of DR+ T cel ls were significantly increased in PEX patients as compared to others. Foll owing long-term PEX treatment, all the laboratory parameters significantly decreased and the clinical scores showed a slight but not significant impro vement. Conversely, in the other group of SSC patients treated for the same period with drugs only, no significant change of laboratory parameters was detected and the clinical scores slightly worsened. Our data suggest that long-term PEX therapy seems to be effective in slowin g down the clinical course of patients with severe and rapidly progressive SSc. (C) 2001 Elsevier Science Ltd. All rights reserved.