{
  "abstract": "Introduction Background/Purpose: RNA polymerase III (RNAP3) antibodies are highly associated with systemic sclerosis (SSc), with an increased risk of severe skin involvement and renal crisis. Some patients who have antibodies against RNAP3, have concomitant antibodies against RNA polymerase I (RNAP1) and RNA polymerase II (RNAP2). RNAP2 antibodies have been associated with SSc, while RNAP1 have been found in patients with SSc, lupus and Sjogren’s (PMID 8390487). A 1999 study of 34 RNAP3+ patients reported 40% of those simultaneously positive for all three antibodies developed high rates of renal crisis (40%)(PMID 10444276).The objective of our study was to evaluate if there was an identifiable clinical phenotype or difference in outcomes or survival in patients who were RNAP3+ alone, versus in combination with either RNAP2 or RNAP1.Material and Methods We identified SSc patients seen for an initial visit between 1980 and 2015 at the University of Pittsburgh. All SSc patients who entered our prospective SSc observational cohort study had serum that underwent ANA by immunofluorescence, immunodiffusion and immunoprecipitation. We identified patients who were RNAP3 positive. We evaluated if the presence of simultaneous antibodies to RNAP2 and/or RNAP1 was associated with increased risks of SSc complications, cancer or mortality. We utilized descriptive statistics, combined with Cox proportional hazards and Kaplan-Meier curve analysis.Results We identified 751 SSc patients who were RNAP3+; 517 were also positive for RNAP1, and 237 for RNAP2 antibodies. Of these, 197 were positive for all three antibodies. Table 1 shows the baseline characteristics of these patients by autoantibody combination group. There were no demographic differences between groups. Organ involvement differences at baseline were significant only for percentage of patients with fibrosis by imaging (p < 0.001) and prior/coexistent cancer (p=0.01), shown in table 1. As of last follow-up, the significant difference between groups remained cancer (p=0.009) incidence (table 2). Long-term survival was not different amongst the antibody groups (p=0.21). Regression analysis, after adjustment for age/gender, did not show an independent significant relationship for either rnap1 or rnap2 antibody for the outcome of cancer; similar results were found for pulmonary fibrosis (table 3).Conclusions Antibodies to RNAP1 and RNAP2 were described in the 1990s, but little was known of their clinical significance with respect to prognosis in SSc patients. In this large study of 751 patients, it does not appear that the co-existence of RNAP1 or RNAP2 with RNAP3 antibody positivity provides any prognostic information with respect to clinical phenotype or survival.Abstract P.055 Table 1Baseline characteristics at the 1st scleroderma center visitAbstract P.055 Table 2SSc features and complications as of last follow-up visitAbstract P.055 Table 3Odds ratios for development of pulmonary fibrosis and cancer as of last follow-up",
  "authors": [
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Maureen Laffoon"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Leah Wunsch"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Namitha Nair"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Kwonho Jeoung"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Lan Yu"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Robert Lafyatis"
    },
    {
      "affiliations": [
        "University of Pittsburgh, Department of Medicine, Pittsburgh, USA"
      ],
      "name": "Robyn Domsic"
    }
  ],
  "title": "P.055 Clinical manifestations and long-term outcomes of systemic sclerosis patients with various combinations of RNA polymerase I, II and III antibodies",
  "uid": "a9c1781e-5e3a-542a-9dbc-f4c3209c8332"
}