Rubella Antibody (IgM)

Message
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Test Code
RUBELM


CPT Codes
86762

Preferred Specimen
1 mL serum


Minimum Volume
0.6 mL


Transport Temperature
Room temperature


Specimen Stability
Room temperature: 4 days
Refrigerated: 7 days
Frozen: 30 days


Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)
Gross hemolysis • Grossly lipemic


Methodology
Immunoassay (IA)

Setup Schedule
Set up: Tues-Sat; Report available: 1-3 days


Reference Range
AU/mL Interpretation
<20.00 Negative
20.00-24.99 Equivocal
≥25.00 Positive


Clinical Significance
Rubella is an acute exanthematous viral infection of children and adults. Rash, fever and lymphadenopathy characterize the illness. While many infections are subclinical, this virus has the potential to cause fetal infection with resultant birth defects. In the absence of a current or recent infection, a demonstration of specific IgG on a serum sample is evidence of immunity to rubella. A positive rubella IgM result does not necessarily indicate current or recent infection. Without a history of exposure to rubella or symptoms consistent with rubella, the IgM result may be difficult to interpret. Rubella IgM can be false positive due to other causes (e.g., parvovirus, rheumatoid factor, cytomegalovirus). Rubella IgM may also persist for more than 12 months after vaccination or natural infection. For a serologic diagnosis of congenital rubella in the neonatal period, antibody to rubella virus should be measured in both infant and maternal sera. If IgM is detected in a newborn infants serum, it is probable that transplacental rubella infection has occurred.


Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153


Last Updated: December 6, 2021


The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.