Antibodies to RNP occur in approximately 50% of patients with lupus erythematosus (LE) and in patients with other connective tissue diseases, notably mixed connective tissue disease (MCTD).
Immediately following collection, thoroughly mix sample by gently inverting 5 times
Gold serum separator (SST) tube
Refrigerated (preferred) - 7 days
Ambient - 24 hours
Chemiluminescent Immunoassay (CIA)
Negative: < 20 CU
Strong positive: ≥ 20 CU