Korean J Lab Med.  2007 Aug;27(4):298-304. 10.3343/kjlm.2007.27.4.298.

Evaluation of BiosewoomTM Real-Q Cytomegalovirus Quantification kit for Cytomegalovirus Viral Load Measure

• Heo WB
• Won DI
• Kim YL
• Kim MH
• Oh HB
• Suh JS

• KMID: 1781500
• DOI: http://doi.org/10.3343/kjlm.2007.27.4.298

Abstract

BACKGROUND: Rapid and accurate laboratory tests are essential to detect cytomegalovirus (CMV) infections in solid organs and haematopoietic stem cell transplant recipients. We assessed the realtime quantitative PCR (RQ-PCR) technology for its usefulness in detecting CMV DNA. METHODS: We evaluated the analytical performance of CMV RQ-PCR using Real-Q Cytomegalovirus Quantification kit (BioSewoom Inc., Korea). To evaluate its clinical utility, we also compared it to pp65 antigenemia test, an immunostaining method, on 343 samples of total 84 patients, including 63 transplant recipients. RESULTS: The detection limit of RQ-PCR was 63 copies/mL and none of hepatitis B virus, hepatitis C virus, or human immunodeficiency virus showed a cross-reactivity with CMV. Total coefficient of variation (CV) was 10.4-19.5%. It detected CMV DNA in a linear range from 1 x 10(2) to 5 x 10(11) copies/mL (P<10(-13), R2=0.9994). The qualitative positive rates of pp65 antigenemia test and RQ-PCR were 4.7%, 16.3%, respectively and concordance rate between the two tests was 84.8% (K=0.221, P<10(-6)). In comparison of quantitative results, the correlation between two tests was significant (r=0.45, P<10(-17)). In comparison among three groups by pp65 antigen level, CMV DNA level obtained with RQ-PCR increased significantly (P<10(-3) and P<10(-7), respectively). CONCLUSIONS: The RQ-PCR is easier to perform than the immunostaining method, has good analytical performance and reflects the blood level of viral DNA well. It may be a new method substituting the pp65 antigenemia test. Further studies determining RQ-PCR value starting pre-emptive therapy will be required.

Keyword

RQ-PCR; pp65 antigenemia test; CMV DNA

MeSH Terms

Adolescent
Adult
Aged
Child
Child, Preschool
Cytomegalovirus/genetics/*isolation & purification
Cytomegalovirus Infections/*diagnosis/virology
DNA, Viral/blood
Female
Humans
Infant
Infant, Newborn
Male
Middle Aged
Phosphoproteins/analysis
Polymerase Chain Reaction/*methods
Reagent Kits, Diagnostic
Reproducibility of Results
Sensitivity and Specificity
Viral Load/*methods
Viral Matrix Proteins/analysis/blood

Figure

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  Fig. 1. Linearity range of Real-Q CMV Quantification kit.

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  Fig. 2. Quantitative comparison of pp65 antigen values and CMV DNA levels obtained by RQ-PCR (r=0.45, P<10-17).

Reference

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