Cost minimization analysis of an in-house molecular test for cytomegalovirus in relation to a commercial molecular system

ABSTRACT Introduction: Cytomegalovirus may cause severe disease in immunocompromised patients. Nowadays, quantitative polymerase chain reaction is the gold-standard for both diagnosis and monitoring of cytomegalovirus infection. Most of these assays use cytomegalovirus automated molecular kits which are expensive and therefore not an option for small laboratories, particularly in the developing world. Objective: This study aimed to optimize and validate an in-house cytomegalovirus quantitative polymerase chain reaction test calibrated using the World Health Organization Standards, and to perform a cost-minimization analysis, in comparison to a commercial cytomegalovirus quantitative polymerase chain reaction test. Study design: The methodology consisted of determining: optimization, analytical sensitivity, analytical specificity, precision, curve variability analysis, and inter-laboratorial reproducibility. Patients (n = 30) with known results for cytomegalovirus tested with m2000 RealTime System (Abbott Laboratories, BR) were tested with the in-house assay, as well as patients infected with other human herpes virus, in addition to BK virus. A cost-minimization analysis was performed, from a perspective of the laboratory, assuming diagnostic equivalence of the methodologies applied in the study. Results: The in-house assay had a limit of detection and quantification of 60.3 IU/mL, with no cross-reactivity with the other viral agents tested. Moreover, the test was precise and had a R 2 of 0.954 when compared with the m2000 equipment. The cost analysis showed that the assay was economically advantageous costing a median value of 37.8% and 82.2% in comparison to the molecular test in use at the hospital and the m2000 equipment, respectively. Conclusions: These results demonstrated that in-house quantitative polymerase chain reaction testing is an attractive alternative in comparison to automated molecular platforms, being considerably less expensive and as efficacious as the commercial methods.

Performance Evaluation of the Real-Q Cytomegalovirus (CMV) Quantification Kit Using Two Real-Time PCR Systems for Quantifying CMV DNA in Whole Blood

Standardized cytomegalovirus (CMV) DNA quantification is important for managing CMV disease. We evaluated the performance of the Real-Q CMV Quantification Kit (Real-Q assay; BioSewoom, Korea) using whole blood (WB), with nucleic acid extraction using MagNA Pure 96 (Roche Diagnostics, Germany). Real-time PCR was performed on two platforms: the 7500 Fast real-time PCR (7500 Fast; Applied Biosystems, USA) and CFX96 real-time PCR detection (CFX96; Bio-Rad, USA) systems. The WHO international standard, diluted with CMV-negative WB, was used to validate the analytical performance. We used 90 WB clinical samples for comparison with the artus CMV RG PCR kit (artus assay; Qiagen, Germany). Limits of detections (LODs) in 7500 Fast and CFX96 were 367 and 479 IU/mL, respectively. The assay was linear from the LOD to 10(6) IU/mL (R2 ≥0.9886). The conversion factors from copies to IU in 7500 Fast and CFX96 were 0.95 and 1.06, respectively. Compared with the artus assay, for values 1,000 copies/mL, 73.3% and 80.6% of samples in 7500 Fast and CFX96, respectively, had <0.5 log10 copies/mL. The Real-Q assay is useful for quantifying CMV in WB with the two real-time PCR platforms.