title: Complementarity between targeted real-time specific PCR and conventional broad-range 16S rDNA PCR in the syndrome-driven diagnosis of infectious diseases.
abstract: Molecular tools have shown an added value in the diagnosis of infectious diseases, in particular for those caused by fastidious intracellular microorganisms, or in patients receiving antibiotics before sampling. If 16S rDNA amplification had been gradually implemented in microbiology laboratories, specific real-time polymerase chain reaction (PCR) would have permitted an increase in the sensitivity of molecular methods and a reduction of contamination. Herein, we report our experience in the diagnosis of infectious diseases over two years, during which 32,948 clinical samples from 18,056 patients were received from France and abroad. Among these samples, 81,476 PCRs were performed, of which 1,192 were positive. Molecular techniques detected intracellular microorganisms in 31.3 % of respiratory samples, 27.8 % of endocarditis samples and 51.9 % of adenitis samples. Excluding intracellular bacteria, 25 % of the positive samples in this series were sterile in culture. Conventional broad-range PCR permitted the identification of fastidious and anaerobic microorganisms, but specific real-time PCR showed a significant superiority in the diagnosis of osteoarticular infections, in particular for those caused by Kingella kingae and Staphylococcus aureus, and for endocarditis diagnosis, specifically when Streptococcus gallolyticus and Staphylococcus aureus were involved. The sensitivity of conventional broad-range PCR was 62.9 % concerning overall diagnoses for which both techniques had been performed. These findings should lead microbiologists to focus on targeted specific real-time PCR regarding the clinical syndrome. Finally, syndrome-driven diagnosis, which consists of testing a panel of microorganisms commonly involved for each syndrome, permitted the establishment of 31 incidental diagnoses.
authors.affiliation: Pôle des Maladies Infectieuses et Tropicales Clinique et Biologique, Fédération de Bactériologie-Hygiène-Virologie, University Hospital Centre Timone, Institut Hospitalo-Universitaire (IHU) Méditerranée Infection, Assistance Publique-Hôpitaux de Marseille, Marseille, France.
authors.forename: A-S
authors.initials: AS
authors.lastname: Morel
authors.forename: G
authors.initials: G
authors.lastname: Dubourg
authors.forename: E
authors.initials: E
authors.lastname: Prudent
authors.forename: S
authors.initials: S
authors.lastname: Edouard
authors.forename: F
authors.initials: F
authors.lastname: Gouriet
authors.forename: J-P
authors.initials: JP
authors.lastname: Casalta
authors.forename: F
authors.initials: F
authors.lastname: Fenollar
authors.forename: P E
authors.initials: PE
authors.lastname: Fournier
authors.forename: M
authors.initials: M
authors.lastname: Drancourt
authors.forename: D
authors.initials: D
authors.lastname: Raoult
mesh_terms: D001424:Bacterial Infections / Q000175:diagnosis* / Q000382:microbiology; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics*; D005602:France; D006801:Humans; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012189:Retrospective Studies; D012680:Sensitivity and Specificity
chemical_list: D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S