Table 3.

Summary of molecular quantitative CMV assays

AssayTurnaround time (h)Sample processing (blood)Reporting of resultsBatch testingLower limit of detectionDynamic range for quantitationReproducibility (coefficient of variation)Equipment and facilities neededAdvantagesDisadvantages
bDNA assay24Recovery of ≥2 × 106 PMNNo. of CMV copies per ml≤41 specimens (+3 controls) (plate format)4 × 103 copies/106leukocytes (version 1); 9 × 102 copies/106leukocytes (version 2)3 log10 (36)Intra- and interassay variabilities of 5.9 and 9.7% (high copy number) and 24.9 and 26.2% (low copy number) (121)Quantiplex bDNA SystemHigh reproducibilityRequires large number of PMNs; long initial incubation period (16–18 h)
Hybrid capture DNA assay6Whole blood (3.5 ml); delayed processing possiblepg of CMV DNA or no. of CMV copies per ml≤48 specimens (+12 controls) per quantitative run (tube format)5 × 103 copies/ml of whole blood (version 1); 7 × 102 copies/ml of whole blood (version 2)2 log10 (16.6–1,660 pg of DNA [version 1]; 2.1–830 pg of DNA [version 2])Intra- and interassay variabilities of 17.8 and 16.3%, respectively (115)LuminometerRapidity of procedure (6 h); simple sample processingMany controls required for quantitative testing
PCR assays24–48aVariable (PMN or plasma); delayed processing possibleNo. of CMV copies per μl of plasma, per 105 PMN, or per μg of DNAVariable (e.g., ≤21 samples and 3 controls per run in plate format for AMPLICOR MONITOR CMV test)Variable (e.g., 5 × 102[qualitative], 2.5 × 103 [quantitative] per ml of plasma [162]; 1 × 103 [qualitative], 4 × 102 [quantitative] per ml of plasma [AMPLICOR CMV test] [167])2–3 log10(23)No data; higher if competitive assay usedThermal cycler; detection devices (spectrophotometer, phosphorimager, etc.)High sensitivityAmplicon contamination; not well standardized; time-consuming
  • a Amplification and detection.