Table 2

Percentage positive among SLE and FM by ANA status

 SLEFM
ANA−ANA+AllANA−ANA+All
Low complement C3/C47% (0% to 19%)27% (15% to 38%)23% (13% to 32%)2% (0% to 6%)0% (NA)1% (0% to 4%)
High CB-CAPs13% (0% to 31%)51% (38% to 64%)43% (32% to 54%)4% (0% to 9%)4% (0% to 12%)4% (0% to 8%)
Anti-dsDNA confirmed by IIF7% (0% to 19%)20% (10% to 30%)17% (9% to 26%)0% (NA)0% (NA)0% (NA)
CB-CAPs in MAAA14% (0% to 33%)73% (60% to 85%)60% (48% to 72%)0% (NA)0% (NA)0% (NA)
  • ANA was determined using IIF and the cut-off for a positive test result was set as ≥1:40. CIs (95%) are provided. Low complement was defined as C3<81 mg/dL or C4<12.9 mg/dL; high CB-CAPs were defined as EC4d≥14 net MFI or BC4d≥60 net MFI.

  • ANA, antinuclear antibodies; CB-CAP, cell-bound complement activation product; dsDNA, double-stranded DNA; FM, fibromyalgia; IIF, indirect immunofluorescence; MAAA, multi-analyte assay with algorithm; MFI, mean fluorescence intensity; NA: not applicable; SLE, systemic lupus erythematosus.