CMV IgM Antibody Detection
|Plasma Separator Tube 4.5 mL
Call laboratory for additional acceptable specimen collection containers.
3.0 mL whole blood from light green top tube or TWO Microtainer® devices.
24 hrs/day, 7 days a week, including holidays.
3 hours (upon receipt in laboratory)
Reference range and methodology changed effective 12/11/2012.
0.8 AI or less: Negative - No significant level of detectable CMV IgM
0.9-1.0 AI: Equivocal - Repeat testing in 10-14 days may be
1.1 AI or greater: Positive - IgM antibody to CMV detected, which may
indicate a current or past CMV infection.
Low levels of CMV IgM antibodies may occasionally persist for more than
12 months post-infection.
In immunocompromised patients, CMV serology (IgG or IgM antibody
titers) may not be reliable and may be misleading in the diagnosis of
acute or reactivation CMV disease. Positive test results may not be
valid in persons who have received blood transfusions or other blood
products within the past several months. A negative result in the CMV
IgM assay does not preclude the possibility of recent primary CMV
infection. Use of the CMV IgM assay in cord blood or neonatal samples
has not been validated.
Multiplex Flow Immunoassay