title: False positive seroreactivity to Borrelia burgdorferi in systemic lupus erythematosus: the value of immunoblot analysis.
abstract: The object of this study was to determine the incidence of seropositivity to B. burgdorferi by the commonly available enzyme-linked immunosorbent assay (ELISA) in patients with SLE and other rheumatic diseases and to evaluate immunoblot analysis as a tool to differentiate true from false positive ELISA. Sera were obtained from patients with SLE (n = 35), rheumatoid arthritis (n = 26), seronegative arthritis (n = 28) and Lyme disease (n = 18). Reactivity to B. burgdorferi antigens was analysed by two available diagnostic techniques: ELISA and immunoblot. Correlations were made between seroreactivity to B. burgdorferi and standard serological tests of autoimmunity: antibodies to nuclear antigens, dsDNA, cardiolipin, SSA and SSB. Seroreactivity to B. burgdorferi antigens by the ELISA system was detected in 40% of patients with SLE, 8% of patients with rheumatoid arthritis and 4% with seronegative arthritis. Among patients seropositive by ELISA, immunoblots were negative in all cases. However, eight of 14 patients with rheumatoid arthritis (57%) showed cross-reactivity to multiple borreli antigens. No significant correlations were found between Lyme seropositivity by ELISA and other autoantibodies except IgM rheumatoid factor (r = 0.61, P < 0.01) in patients with rheumatoid arthritis.
  
  
  CONCLUSIONS
  a positive ELISA for Lyme disease was found in up to 40% of patients with established SLE and also in other rheumatic diseases. However, specific serum antibodies to Borrelia were not confirmed by the more specific immunoblot technique.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Rheumatology, Hospital for Joint Diseases Orthopaedic Institute, New York, USA.
authors.forename: N L
authors.initials: NL
authors.lastname: Weiss
authors.forename: V A
authors.initials: VA
authors.lastname: Sadock
authors.forename: L H
authors.initials: LH
authors.lastname: Sigal
authors.forename: M
authors.initials: M
authors.lastname: Phillips
authors.forename: P F
authors.initials: PF
authors.lastname: Merryman
authors.forename: S B
authors.initials: SB
authors.lastname: Abramson
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood*; D015748:Borrelia burgdorferi Group / Q000276:immunology*; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D006801:Humans; D015151:Immunoblotting; D008180:Lupus Erythematosus, Systemic / Q000276:immunology*; D008193:Lyme Disease / Q000175:diagnosis
chemical_list: D000907:Antibodies, Bacterial