Cytomegalovirus (CMV) Antibodies, IgM, Serum
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Diagnosis of primary, acute phase infection with cytomegalovirus (CMV), especially in patients with infectious mononucleosis and pregnant women who, based on clinical signs or exposure, may have primary CMV infection
Multiplex Flow Immunoassay (MFI)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
Cytomegalovirus Ab, IgM, S
Cytomegalovirus, IgM (Immunoglobulin M)
Cytomegalovirus, IgM (Immunoglobulin M)
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Preferred: Red top
Acceptable: Serum gel
Specimen Volume: 0.5 mL
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Mild OK; Gross reject
Mild OK; Gross reject
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Serum||Refrigerated (preferred)||14 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Cytomegalovirus (CMV) is a member of the Herpesviridae family of viruses and usually causes asymptomatic infection after which it remains latent in patients, primarily within bone marrow derived cells.(1) Primary CMV infection in immunocompetent individuals may also manifest as a mononucleosis-type syndrome, similar to primary Epstein-Barr virus infection, with fever, malaise, and lymphadenopathy.
CMV is a significant cause of morbidity and mortality among bone marrow or solid organ transplant recipients, individuals with AIDS and other immunosuppressed patients due to virus reactivation or from a newly acquired infection.(2,3) Infection in these patient populations can affect almost any organ and lead to multiorgan failure. CMV is also responsible for congenital disease among newborns and is 1 of the TORCH infections (toxoplasmosis, other infections including syphilis, rubella, CMV, and herpes simplex virus).
CMV seroprevalence increases with age. In the United States the prevalence of CMV specific antibodies increases from approximately 36% to over 91% in adolescents between the ages of 6 to 11 and adults over 80 years old, respectively.(4)
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Negative (Reported as positive, negative, or equivocal)
A negative cytomegalovirus (CMV) IgM results suggest that the patient is not experiencing a recent infection. However, a negative result does not rule-out primary CMV infection.
It has been reported that CMV-specific IgM antibodies were not detectable in 10% to 30% of cord blood sera from infants demonstrating infection in the first week of life. In addition, up to 23% (3/13) of pregnant women with primary CMV infection did not demonstrate detectable CMV IgM responses within 8 weeks postinfection. In cases of primary infection where the time of seroconversion is not well defined as high as 28% (10/36) of pregnant women did not demonstrate CMV-IgM antibody.
Positive CMV IgM results indicate a recent infection (primary, reactivation, or reinfection).
IgM antibody responses in secondary (reactivation) CMV infections have been demonstrated in some CMV mononucleosis patients, in a few pregnant women, and in renal and cardiac transplant patients. Levels of antibody may be lower in transplant patients with secondary, rather than primary, infections.
Equivocal CMV IgM results may occur during acute infection or may be due to nonspecific binding reactions. Submit an additional sample for testing if clinically indicated.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Sera drawn very early during the acute stage of infection may have undetectable levels of cytomegalovirus (CMV) IgM.
Immunocompromised patients may have impaired immune responses and nonreactive IgM results may be due to delayed seroconversion and do not rule-out current infection.
CMV IgM results should not be used alone to diagnose CMV infection. Results should be considered in conjunction with clinical presentation, patient history, and other laboratory findings. In cases of suspected disease, submit a second sample for testing in 10 to 14 days.
The performance characteristics of these assays have not been evaluated in immunosuppressed or organ transplant recipients and have not been established for cord blood or for testing of neonates. These assays should not be used for screening blood or plasma donors.
Immune complexes or other immunoglobulin aggregates present in patient samples may cause increased nonspecific binding and produce false-positive results.
Potential cross-reactivity for CMV IgM may occur with specimens positive for Epstein-Barr virus VCA IgM and parvovirus B19 IgM.
To evaluate the accuracy of the BioPlex cytomegalovirus (CMV) IgM multiplex flow immunoassay, 600 prospective serum specimens submitted for routine CMV IgM testing by the VIDAS enzyme-linked fluorescence immunoassay (ELFA; bioMerieux, Durham, NC) were also analyzed in a blinded fashion by the BioPlex assay within a 24-hour period. Specimens with discordant results after initial testing were repeated by both assays during the same freeze/thaw cycle. Further resolution of discrepant results was performed by using the DiaMedix (Miami, FL) EIA CMV IgM EIA. The resolved results are summarized below:
CMV IgM (VIDAS ELFA)
BioPlex CMV IgM
(a) These 15 specimens tested negative by the DiaMedix EIA.
Sensitivity: 93.7% (15/16); 95% Confidence Interval (95% CI): 69.7%-100%
Specificity: 96.7% (556/574); 95% CI: 95.1%-98.0%
Overall Percent Agreement: 95.7% (574/600); 95% CI: 93.7%-97.4%
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
1. Soderberg-Naucler C, Khanna R, et al: Reactivation of latent human cytomegalovirus by allogeneic stimulation of blood cells from healthy donors. Cell 1997;91:119
2. Kusne S, Shapiro R, Fung J: Prevention and treatment of cytomegalovirus infection in organ transplant recipients. Transpl Infect Dis 1999;1(3):187-203
3. Rubin RH: Importance of CMV in the transplant population. Transpl Infect Dis 1999;1(1):3-7
4. Staras SA, Dollard SC, Radford KW, et al: Seroprevalence of cytomegalovirus infection in the United States, 1998-1994. Clin Infect Dis 2006;43(9):1143
Method Description Describes how the test is performed and provides a method-specific reference
The BioPlex 2200 cytomegalovirus (CMV) IgM assays uses multiplex flow immunoassay technology. Briefly, CMV antigen coated fluorescent beads are mixed with an aliquot of patient sample and sample diluted and incubated at 37 degrees C. During this time IgM anti-CMV antibodies in the specimen will bind to the CMV antigen on the beads. After a wash cycle, a fluorescently labeled antihuman-IgM antibody conjugate is added to the mixture and incubated at 37 degrees C. Following a wash step to remove unbound conjugate, the bead mixture is passed through a detector that identifies the bead based on dye fluorescence and determines the amount of antibody captured by the antigen based on fluorescence of the antihuman-IgM conjugate. Raw data is calculated in relative fluorescence intensity and is converted to an antibody index for interpretation.
Three additional dyed beads, an internal standard bead, a serum verification bead, and a reagent black bead are present in each reaction mixture to verify detector response, the addition of serum to the reaction vessel and the absence of significant nonspecific binding in serum, respectively.(Package insert: BioPlex 2200 System, ToRC IgG, Bio-Rad Laboratories, Clinical Diagnostics Group, Hercules, CA)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Monday through Saturday; 9 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Same day/1 day
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test has been cleared or approved by the U.S. Food and Drug Administration and is used per manufacturer's instructions. Performance characteristics were verified by Mayo Clinic in a manner consistent with CLIA requirements.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|CMVM||Cytomegalovirus Ab, IgM, S||In Process|