Evaluation of four methods for cytomegalovirus antibody detection for use by a bone marrow transplantation service

Maternal IgM antibody status in confirmed fetal cytomegalovirus infection detected by sonographic signs

OBJECTIVE

To evaluate the value of maternal IgM to cytomegalovirus (CMV) as a predictive factor of fetal infection in fetuses with sonographic markers.

METHODS

Observational study (2006-2011) including a consecutive series of 19 fetuses with sonographic markers of fetal infection and confirmed infection by positive CMV-DNA in amniotic fluid or fetal blood. We evaluated the status of maternal CMV IgM at the time of sonographic suspicion.

RESULTS

During this 6-year study period, CMV infection was diagnosed in 19 fetuses from 18 pregnancies, including 16 singletons, both twins of a monochorionic diamniotic pregnancy and one twin of a dichorionic pregnancy. Sonographic suspicion was established on the basis of one or more of the following: brain abnormalities (14), fetal hydrops (4), hyperechogenic bowel (4), pericardial effusion (1), cardiomegaly (1), oligoanhydramnios (4), and placentomegaly (2). Maternal IgG antibodies were positive in all cases but maternal IgM antibodies were negative in 56% of pregnancies. Five of the 10 pregnancies with negative maternal IgM were diagnosed in the second trimester and five in the third trimester.

CONCLUSION

In around half of fetuses with confirmed CMV infection ascertained by sonographic markers, maternal IgM antibodies are negative and should therefore not be used as a diagnostic parameter.

Results of a quality assurance program for detection of cytomegalovirus infection in the pediatric pulmonary and cardiovascular complications of vertically transmitted human immunodeficiency virus infection study

A quality assurance program was established by the Pediatric Pulmonary and Cardiovascular Complications of Vertically Transmitted Human Immunodeficiency Virus Type 1 Infection Study Group for monitoring cytomegalovirus (CMV) antibody and culture results obtained from nine different participating laboratories. Over a 3-year period, every 6 months, each laboratory was sent by the designated reference laboratory six coded samples: three urine samples for CMV detection and three serum samples for CMV immunoglobulin G (IgG) and IgM antibody determination. Overall, the participating laboratories exhibited the following composite performance statistics, relative to the reference laboratory (sensitivity and specificity, respectively): 100 and 97.4% for CMV cultures, 95.5 and 94.4% for CMV IgG antibody assays, and 92.6 and 90.2% for CMV IgM assays. The practice of having individual laboratories use different commercial methods and reagents for CMV detection and antibody determination was successfully monitored and provided useful information on the comparable performance of different assays.

Comparison of two enzyme immunoassays and two latex agglutination assays for detection of cytomegalovirus antibody

Two commercially available enzyme immunoassays for cytomegalovirus (CMV) immunoglobulin G (IgG), Vidas and Diamedix, and two latex agglutination tests that detect both CMV IgG and IgM, CMV-Scan and CMV-Gen, were evaluated using 165 human serum specimens. Among these, 46.7% contained CMV-reactive antibody. The first three assays had sensitivities of 100%; the sensitivity of the CMV-Gen procedure was 98.7%. The specificities of the four tests were 100, 97.7, 97.3, and 93.2%, respectively.

Comparison of four enzyme immunoassays for the detection of cytomegalovirus IgG antibodies

Four commercial enzyme immunoassays (EIA), namely the Behring Enzygnost EIA (BE-EIA), Abbott IMx, Whittaker CMV STAT Test Kit and Diamedix assay, were evaluated for the detection of CMV IgG. The methods were compared as to sensitivity, specificity, positive and negative predictive values, global agreement, ease of performance and, for a small number of specimens, reproducibility. Discordant results were resolved by using the Gull CMV indirect fluorescent antibody (IFA) method. Our data suggest that all four assays were valuable screening tools for the detection of CMV IgG based on their high sensitivity and high negative predictive value. However, differences were noted in the reproducibility level and in the incidence of false-positive, equivocal and nonspecific results regarding certain tests in particular. In our hands, the Abbott IMx and the BE-EIA ranked high in the performance characteristics for a good screening test, yet the Abbott IMx offers the added advantages of being the easiest to perform and having the most rapid turnaround time.

Evaluation of latex agglutination and dot immunobinding assay for the detection of cytomegalovirus antibody

The Virogen CMV Antibody Test and Difco CMV-Cube were compared with three other available methods, enzyme immunoassay, immunofluorescence and latex agglutination, for the detection of cytomegalovirus (CMV) antibody in 126 random sera submitted to the clinical laboratory. Based on concordance of three or more methods, 72% of the samples were positive for CMV antibody. The sensitivities and specificities of the assays were Virogen, 98% and 97%, and CMV-Cube 97% and 97%, respectively.

Evaluation of the CMV-CUBE assay for detection of cytomegalovirus serologic status in marrow transplant patients and marrow donors

We evaluated a new membrane dot immunobinding assay (CMV-CUBE; Difco Laboratories) for the detection of cytomegalovirus (CMV) antibody in marrow transplant patients and donors. The CMV-CUBE assay was compared with a commercially available enzyme immunoassay (EIA; CMV STAT) and a latex agglutination (LA; CMVScan) test. Serum samples were collected from 311 transplant patients and donors prior to transplantation. A total of 164 serum specimens were positive for CMV antibody by one or more of the three assays, with 153 of 164 samples (93.3%) positive by all three tests. A total of 147 serum specimens were CMV antibody negative. CMV-CUBE detected 154 of 164 (94%) of the positive samples, EIA detected 160 of 164 (97.5%), and LA detected 157 of 164 (95.7%) CMV-positive samples. Compared with EIA, CMV-CUBE had a sensitivity of 95.6% and a specificity of 99.3%. Compared with LA, CMV-CUBE had a sensitivity of 97.5% and a specificity of 99.4%. CMV-CUBE is a simple and rapid visual assay which can be used for the qualitative detection of antibody to CMV in patient serum.

Evaluation of a latex particle agglutination assay for the detection of cytomegalovirus antibody in patient serum

The Virogen CMV Antibody Test is a simple and rapid latex agglutination assay for the detection of cytomegalovirus antibody in human serum and plasma. Evaluation of this assay with respect to enzyme immunoassay yielded a sensitivity of 98% with a specificity of 100%. In comparison to CMVScan, the Virogen CMV Antibody Test had a sensitivity of 98.4% and a specificity of 100%.