Anti-PM-Scl antibody in patients with systemic sclerosis

Clin Exp Rheumatol. Mar-Apr 2012;30(2 Suppl 71):S12-6. Epub 2012 May 29.

Abstract

Objectives: To compare systemic sclerosis (SSc) patients with and without anti-PM-Scl antibody.

Methods: We reviewed the medical records of 76 anti-PM-Scl antibody positive SSc patients and 2349 anti-PMScl negative SSc patients first evaluated during 1980-2004. Patients were included if they had a clinical diagnosis of SSc either alone or in overlap with another connective tissue disease. Anti-PM-Scl antibody was screened for by indirect immunofluorescence and tested by Ouchterlony double immunodiffusion.

Results: Anti-PM-Scl antibody positive patients had a significantly higher frequency of a positive ANA with nucleolar staining (87% vs. 32%, p<0.0001) and were younger at both symptom onset (p=0.004) and first physician diagnosis of SSc (p<0.001). They were classified more often as having overlap with another connective tissue disease, particularly polymyositis-dermatomyositis, and more frequently had limited cutaneous involvement (72% vs. 52%, p=0.001). Maximal skin thickening was less in anti-PM-Scl antibody patients (mean modified Rodnan total skin score 6.0±6.3 vs. 15.9±14.2, p<0.001). Anti-PM-Scl antibody positive patients less frequently had peripheral vascular (91% vs. 98%, p=0.0002) and gastrointestinal (52% vs. 79%, p=0.0001) disease. Lung involvement overall had a similar distribution between both groups. However, radiographic evidence of pulmonary fibrosis was more frequent in anti-PM-Scl antibody positive patients (50% vs. 37%, p=0.05) and pulmonary arterial hypertension was less often detected (5% vs. 15%, p<0.04). Skeletal muscle involvement (51% vs. 14%, p<0.0001) and subcutaneous calcinosis (p<0.003) were both significantly more often observed in anti-PM-Scl antibody positive patients. Joint, heart, and kidney involvement were similar in both groups. Overall survival was significantly better for anti-PM-Scl antibody positive patients (10 year cumulative survival rate 91% vs. 65%, p=0.0002). After adjustment for age, sex and limited vs. diffuse cutaneous involvement, patients with anti-PM-Scl antibody were significantly less likely to die (HR=0.32, 95% CI, [0.14, 0.72] p=0.006).

Conclusions: SSc patients with anti-PM-Scl antibody are younger and significantly more often have limited cutaneous involvement, skeletal muscle disease, pulmonary fibrosis and calcinosis compared to anti-PM-Scl antibody negative SSc patients. Ten-year cumulative survival is significantly better in anti-PM-Scl antibody positive SSc patients.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Age Factors
  • Autoantibodies / blood*
  • Disease Progression
  • Exoribonucleases / immunology*
  • Exosome Multienzyme Ribonuclease Complex
  • Female
  • Fluorescent Antibody Technique
  • Humans
  • Immunodiffusion
  • Kaplan-Meier Estimate
  • Male
  • Middle Aged
  • Nuclear Proteins / immunology*
  • Pennsylvania
  • Prognosis
  • Proportional Hazards Models
  • Risk Assessment
  • Risk Factors
  • Scleroderma, Systemic / blood
  • Scleroderma, Systemic / complications
  • Scleroderma, Systemic / diagnosis
  • Scleroderma, Systemic / immunology*
  • Scleroderma, Systemic / mortality
  • Severity of Illness Index
  • Time Factors
  • Young Adult

Substances

  • Autoantibodies
  • Nuclear Proteins
  • Exoribonucleases
  • Exosome Multienzyme Ribonuclease Complex
  • EXOSC10 protein, human