CMV IgM Antibody Detection
Label Mnemonic: CMVM
Epic Lab Code: LAB938
Downtime Form: A-1a General Laboratory Requisition
Chemistry
6240 RCP
356-3527
Specimen(s):
Plasma
Collection Medium:
Plasma Separator Tube 4.5 mL
Alternate Collection Media:
Call laboratory for additional acceptable specimen collection containers.
Minimum:
3.0 mL whole blood from light green top tube or TWO Microtainer® devices.
Testing Schedule:
24 hrs/day, 7 days a week, including holidays.
Turn Around Time:
3 hours (upon receipt in laboratory)
Reference Range:
Reference range and methodology changed effective 12/11/2012.

0.8 AI or less: Negative - No significant level of detectable CMV IgM antibody.

0.9-1.0 AI: Equivocal - Repeat testing in 10-14 days may be helpful.

1.1 AI or greater: Positive - IgM antibody to CMV detected, which may indicate a current or past CMV infection.
Comments:
Low levels of CMV IgM antibodies may occasionally persist for more than 12 months post-infection.
Test Limitations:
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.
Methodology:
Multiplex Flow Immunoassay
CPT Code:
86645