Clinical evaluation of NucliSENS magnetic extraction and NucliSENS analytical specific reagents for the real-time detection of respiratory syncytial virus (RSV) in paediatric respiratory specimens.

AIMS

To evaluate the combination of NucliSENS magnetic extraction and NucliSENS analytical specific reagents (bioMérieux, Marcy L'Etoile, France) for the detection of respiratory syncytial virus (RSV) from a variety of respiratory samples.

METHODS

Nucleic acids (NA) from paediatric samples (n = 603) and an RSV-specific inhibition control (R-IC) were coextracted using the miniMAG and/or the easyMAG. Nucleic-acid-sequence-based amplification (NASBA) and molecular beacon detection of RSV and R-IC were performed using NucliSENS analyte-specific reagents (NRSVA) and the NucliSENS EasyQ Analyzer. NRSVA results were compared with R-Mix culture and direct fluorescent antibody detection (DFA).

RESULTS

The NRSVA analytical specificity was 100%, and the NRSVA limit of detection was 5-20 RNA copies/reaction. The prediscordant analysis, sensitivity, specificity, PPV and NPV were, respectively, for R-Mix (64.7%, 100%, 100%, 94.5%); DFA (98.8%, 99.0%, 94.4%, 99.8%); NRSVA (94.1%, 95%, 75.5%, 99%). After discordant analysis, sensitivity, specificity, PPV and NPV were, respectively, for R-Mix (56.7%, 100%, 100%, 92.3%); DFA (87.6%, 99.2%, 95.5%, 97.7%); NRSVA (93.8%, 97%, 85.9%, 99%). RSV was detected in 17.8% of the samples and in seven coinfections. Children with proven RSV infection, compared with children without a pathogen identified, had shorter median hospitalisation stays (2 days vs 3 days, p = 0.035), used fewer antibiotics (54% vs 69%) and had shorter durations of antibiotic therapy (6.2 days vs 9.3 days, p = 0.021), respectively.

CONCLUSIONS

NRSVA is sensitive and specific for RSV detection in respiratory samples. The R-IC monitored the test process, including NA extraction, target amplification and detection. The rapid detection of respiratory pathogens can foster appropriate patient management.