Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1344 page)

   
Normal values:
Not detected when the result is below the level of detection of the assay.

   Use

   Management of CMV-infected individuals undergoing antiviral therapy

   Individuals at risk of severe CMV infection

   Confirmation of the presence CMV infection

   Limitations

   Caution should be taken when interpreting results obtained by different laboratories or assay methodologies. Use of IU/mL units is intended to make comparison possible. PCR inhibitors in the patient specimen may lead to underestimation of viral quantitation or in rare cases, false-negative results.

CYTOMEGALOVIRUS (CMV) SEROLOGY IGG AND IGM

   Definition

   Human CMV is a herpes virus. It is ubiquitous, species specific, and spread by close human contact. Primary infection may be acquired through different transmission routes and in different periods of life (e.g., congenital, perinatal and postnatal infections). Serologic diagnosis of CMV infection relies on the detection of IgG and IgM antibodies. CMV IgM appears within 2–4 weeks and persists for several weeks. In addition, CMV IGM may reappear during secondary CMV infection. CMV IgG can be detected typically after 4 weeks and persists for years to life. Unequivocal diagnosis of CMV primary infection is achieved by documenting a CMV IgG seroconversion on acute convalescent pair of serum samples.

   Use

   Aids in the diagnosis of mononucleosis-like illness in immunocompetent patients

   Discriminates between current (IgM) and prior infections (IgG). Suspected CMV infection based on presentation in immunocompromised patients. Congenital syndrome that presents with symptoms of CMV

   Interpretation