Analytical and clinical performance of a novel DiaRD CMV qPCR assay for cytomegalovirus DNA quantification: a comparative study with the artus CMV RG PCR kit.

Abstract

Background: Cytomegalovirus (CMV) remains a major cause of morbidity in transplant recipients and patients with hematological malignancies, requiring accurate viral load monitoring for clinical management. This study evaluated the performance of the novel DiaRD CMV qPCR assay compared with the reference artus CMV RG PCR Kit.

Research design and methods: A total of 180 anonymized plasma samples, including 47 CMV-positive and 133 CMV-negative specimens, were retrospectively analyzed. Diagnostic accuracy, quantitative agreement, analytical specificity, and precision were assessed.

Results: The DiaRD assay correctly identified 45 of 47 positive samples, yielding a sensitivity of 95.7% and specificity of 96.2%, with an overall accuracy of 96.1%. Positive and negative predictive values were 90.0% and 98.5%, respectively. Quantitative analysis demonstrated strong correlation between assays (R² = 0.880, r = 0.938, p < 0.0001). Bland-Altman analysis showed good agreement, with a mean difference of -0.009 log₁₀ IU/mL (SD: 0.272). Among concordant positive samples, 40 showed differences of <0.5 log₁₀ IU/mL. No cross-reactivity was detected with other tested pathogens. Precision studies demonstrated coefficients of variation below 2% for Ct values and ≤6.81% for viral loads.

Conclusion: Overall, the DiaRD CMV qPCR assay demonstrated reliable analytical and diagnostic performance, supporting its suitability for routine CMV DNA quantification in clinical laboratories.