Testing implications of varying targets for Bordetella pertussis: comparison of the FilmArray Respiratory Panel and the Focus B. pertussis PCR assay

BACKGROUND: The FilmArray Respiratory Panel (RP) detects multiple pathogens, including Bordetella pertussis. The multiplex PCR system is appropriate for a core laboratory or point of care due to ease of use. The purpose of this study is to compare the analytical sensitivity of the FilmArray RP, which targets the promoter region of the B. pertussis toxin gene, with the Focus real-time PCR assay, which targets the insertion sequence IS481. METHODS: Seventy-one specimens from patients aged 1 month to 18 years, which had tested positive for B. pertussis using the Focus assay, were analysed using the FilmArray RP. RESULTS: Forty-six specimens were positive for B. pertussis by both the Focus and the FilmArray RP assays. Twenty-five specimens were negative for B. pertussis using the FilmArray RP assay, but positive using the Focus assay. CONCLUSIONS: The FilmArray RP assays will detect approximately 1/3 less cases of B. pertussis than the Focus assay.