Evaluation of real-time RT-PCR Rhino&EV/Cc r-gene® (bioMérieux) kit versions 1 and 2 for rhinovirus detection

Abstract Background Human rhinoviruses (HRVs) are frequent etiologic agents of tract infections, ranging from benign upper to potentially life-threatening lower respiratory tract infections. Diagnosis is based on molecular methods. 169 HRV types, belonging to species A, B and C, have been identified. This high genetic diversity makes it difficult to accurately detect circulating HRVs and to diagnose severe infection. Objectives To comparatively assess the ability to detect HRV clinical isolates of the first version (V1) of the commercial real-time RT-PCR Rhino&EV/Cc r-gene ® (bioMerieux) kit, of an in-house RT-PCR followed by genotyping, considered as the reference method, and of the second version of this commercial test (V2). Study design From September 2011 to April 2013, HRVs were prospectively detected in 2525 respiratory specimens, using V1 in combination with the in-house reference RT-PCR. In November 2013, 85 specimens that had given initially false negative results with V1 were retested simultaneously with V1 and V2 and the in-house RT-PCR. In addition, 421 negative specimens with the in-house assay were prospectively tested with V2. Results Among the 2525 specimens, V1 detected 80.7% (502/622) of in-house RT-PCR positive isolates: 85.3% (220/258) of HRV-A, 84.4% (27/32) of HRV-B and 74.9% (176/235) of HRV-C. Among the 85 respiratory samples tested with V1, V2 and the in-house RT-PCR, V2 was more efficient than V1 in detecting 16 HRV isolates: 11/33 (33.3%) of HRV-A and 5/47 (10.6%) of HRV-C tested. The analytical sensitivity of V2 was greater for 8/18 HRV-A genotypes and 2/22 HRV-C genotypes. Relative to the in-house assay, the specificity of V2 was 100% (421/421). Conclusions This study showed a slightly higher sensitivity of V2. However, diverse genotypes, especially HRV-C, were undetected.