Evaluation of a Real-Time Reverse Transcription-PCR Assay for Detection of Enterovirus D68 in Clinical Samples from an Outbreak in New York State in 2014

Abstract

Cystic fibrosis (CF) is the most frequent genetic lethal disease in Caucasian population. Lung destruction is the principal cause of death by chronic P. aeruginosa colonization. There is a high prevalence of oropharyngeal anaerobic bacteria in sputum of CF patients. This study was carried out due to the lack of results comparing subgingival periodontal pathogenic bacteria between CF oral cavity and lungs in relation with P. aeruginosa presence. Our first goal was to detect P. aeruginosa in oral and sputum samples by culture and molecular methods, and to determine clonality of isolates. In addition, subgingival periodontal anaerobic bacteria were searched for in sputum. A cross sectional pilot case-control study was conducted in the CF Reference Center in Roscoff, France. Ten ΔF508 homozygous CF patients were enrolled (5 chronically colonized (CC) and 5 not colonized (NC)). P.aeruginosa was detected in saliva, sputum and subgingival plaque samples by real-time PCR (qPCR). Subsequently, periodontal bacteria were also detected and quantified in subgingival plaque and sputum samples by qPCR. In CC patients P. aeruginosa was recovered in saliva and subgingival plaque samples. Sixteen P. aeruginosa strains were isolated in saliva and sputum in this group and compared by Pulsed Field Gel Electrophoresis (PFGE). Subgingival periodontal anaerobic bacteria were found in sputum samples. A lower diversity of these species was recovered in the CC patients compared to NC patients. Presence of the same P.aeruginosa clonal types in saliva and sputum samples underlines that the oral cavity is a possible reservoir for lung infection.