title: A Chlorhexidine- Agar Plate Culture Medium Protocol to Complement Standard Broth Culture of Mycobacterium tuberculosis.
abstract: The culture of Mycobacterium tuberculosis using parallel inoculation of a solid culture medium and a liquid broth provides the gold standard for the diagnosis of tuberculosis. Here, we evaluated a chlorhexidine decontamination-MOD9 solid medium protocol versus the standard NALC-NaOH-Bactec 960 MGIT protocol for the diagnosis of pulmonary tuberculosis by culture. Three-hundred clinical specimens comprising 193 sputa, 30 bronchial aspirates, 10 broncho-alveolar lavages, 47 stools, and 20 urines were prospectively submitted for the routine diagnosis of tuberculosis. The contamination rates were 5/300 (1.7%) using the MOD9 protocol and 17/300 (5.7%) with the Bactec protocol, respectively (P < 0.05, Fisher exact test). Of a total of 50 Mycobacterium isolates (48 M. tuberculosis and two Mycobacterium abscessus) were cultured. Out of these 50, 48 (96%) isolates were found using the MOD9 protocol versus 35 (70%) when using the Bactec protocol (P < 0.05, Fisher exact test). The time to positivity was 10.1 ± 3.9 days versus 14.7 ± 7.3 days, respectively, (P < 0.05, Student's t-test). These data confirmed the usefulness of parallel inoculation of a solid culture medium with broth for the recovery of M. tuberculosis in agreement with current recommendations. More specifically, chlorhexidine decontamination and inoculation of the MOD9 solid medium could be proposed to complement the standard Bactec 960 MGIT broth protocol.
authors.affiliation: URMITE, UMR CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université Marseille, France.
authors.forename: Shady
authors.initials: S
authors.lastname: Asmar
authors.affiliation: Innovation Unit, BioMérieux SA La Balme Les Grottes, France.
authors.forename: Sonia
authors.initials: S
authors.lastname: Chatellier
authors.affiliation: Innovation Unit, BioMérieux SA La Balme Les Grottes, France.
authors.forename: Caroline
authors.initials: C
authors.lastname: Mirande
authors.affiliation: R&D Microbiology, BioMérieux SA La Balme Les Grottes, France.
authors.forename: Alex
authors.initials: A
authors.lastname: van Belkum
authors.affiliation: Innovation Unit, BioMérieux SA La Balme Les Grottes, France.
authors.forename: Isabelle
authors.initials: I
authors.lastname: Canard
authors.affiliation: URMITE, UMR CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université Marseille, France.
authors.forename: Didier
authors.initials: D
authors.lastname: Raoult
authors.affiliation: URMITE, UMR CNRS 7278, IRD 198, INSERM 1095, Aix Marseille Université Marseille, France.
authors.forename: Michel
authors.initials: M
authors.lastname: Drancourt
keywords: Bactec 960 MGIT; MOD9; Mycobacterium tuberculosis; N-acetyl-cysteine-sodium chloride; chlorhexidine; decontamination; diagnosis
references.citation: J Clin Microbiol. 2006 Jun;44(6):2237-9
references.pmid: 16757627
references.citation: Sci Rep. 2014 Feb 28;4:4236
references.pmid: 24577292
references.citation: J Clin Microbiol. 2015 Aug;53(8):2566-9
references.pmid: 26041897
references.citation: BMC Microbiol. 2015 Aug 05;15:155
references.pmid: 26238865