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).

Gold serum separator (SST) tube

Immediately following collection, thoroughly mix sample by gently inverting 5 times

1. Allow sample to clot for a minimum of 30 minutes
2. Spin within two (2) hours of sample collection

Gold serum separator (SST) tube

Red serum vial/tube - 5 mL

Red/grey serum separator (SST) vial/tube, 10 mL

1. Allow sample to clot
2. Spin
3. Transfer serum to a False bottom plasma/serum transport vial/tube (AHL), labelled as serum, within two (2) hours of sample collection

False bottom plasma/serum transport vial/tube (AHL)

Red/grey serum separator (SST) vial/tube, 10 mL

Refrigerated (preferred) - 7 days

Frozen (OK)

Ambient - 24 hours

• Improper labels (unlabeled or mislabeled)
• Hemolysis (some procedures)
• Improper anticoagulant or ratio
• Delay in transport
• Improper storage temperature affecting results
• Improper container
• Leaking container resulting in compromised specimen
• Quantity not sufficient (QNS)

Chemiluminescent Immunoassay (CIA)

Negative: < 20 CU

Strong positive: ≥ 20 CU