ARUP's Laboratory Test Directory

Rubella Antibody, IgM : 0050551

Mnemonic: RUBEIGM

Methodology: Chemiluminescent Immunoassay
Performed: Sun-Sat
Reported: Within 24 hours
Specimen Required: Collect: Serum separator tube.

Specimen Preparation: Allow specimen to clot completely at room temperature. Separate serum from cells ASAP or within 2 hours of collection. Transfer 1 mL serum to an ARUP Standard Transport Tube. (Min: 0.5 mL) Parallel testing is preferred and convalescent specimens must be received within 30 days from receipt of acute specimens. Mark specimens plainly as "acute" or "convalescent."

Storage/Transport Temperature: Refrigerated.

Unacceptable Conditions: Urine. Contaminated, heat-inactivated, or hemolyzed specimens.

Stability (collection to initiation of testing): After separation from cells: Ambient: 48 hours; Refrigerated: 2 weeks; Frozen: 1 year (avoid repeated freeze/thaw cycles)
Reference Interval:
 
19.9 AU/mL or less: Not Detected.
20.0 - 24.9 AU/mL: Indeterminate - Repeat testing in 10-14 days may be helpful.
25.0 AU/mL or greater: Detected - IgM antibody to rubella detected, which may indicate a current or recent infection or immunization.

Interpretive Data: Testing immediately post-exposure is of no value without a later convalescent specimen. While the presence of IgM antibodies suggests current or recent infection, low levels of IgM antibodies may occasionally persist for more than 12 months post-infection or immunization.
CPT Code(s): 86762