Association between sequevar and antibiotic treatment outcome in patients with Mycobacterium abscessus complex infections in Japan.

Purpose: Macrolide susceptibility differs between subspecies in the Mycobacterium abscessus complex, likely due to differences in erm(41) sequevars. Patients with M. abscessus complex infection generally show poor clinical outcomes in response to antibiotic treatment.

[Genetic analysis reveals misidentification of Mycobacterium lentiflavum as Mycobacterium intracellulare by the COBAS TaqMan MAI test].

Objective: To evaluate COBAS TaqMan MAI test misidentification of Mycobacterium lentiflavum as Mycobacterium intracellulare.

Materials And Methods: Preliminary comparative analysis identified 13 clinical isolates used in this study as COBAS Amplicor MAV and MIN-negative but COBAS TaqMan MAI-positive. The COBAS TaqMan MAI test limit of detection and reproducibility were evaluated by tenfold dilution series from 3 x 10(8) CFU/mL.

Rapid identification of strains belonging to the Mycobacterium abscessus group through erm(41) gene pyrosequencing.

Mycobacterium abscessus and Mycobacterium massiliense lung infections have different clarithromycin susceptibilities, making proper identification important; however, standard multi-gene sequencing in clinical laboratories is laborious and time consuming. We developed a pyrosequencing-based method for rapid identification of strains belonging to the M. abscessus group by targeting erm(41).

[Comparative evaluation of acid-fast staining for the detection of Mycobacterium fortuitum--clinical performance of fluorescent and Ziehl-Neelsen staining].

Objective: Fluorescent staining is of paramount importance, not only for confirming the presence of mycobacteria in a given specimen but also for providing an estimated growth quantification. In this study, for rapidly growing Mycobacterium fortuitum, we evaluated the effectiveness of a rapid fluorescent staining method employing auramine-rhodamine (AR) fluorescent stain and acridine-orange (AO) fluorescent stain compared to that of the standard Ziehl-Neelsen (ZN) stain currently in use in our laboratory.

Method: We evaluated the acid-fast nature of M.

Further isolation of Mycobacterium abscessus subsp. abscessus and subsp. bolletii in different regions of Japan and susceptibility of these isolates to antimicrobial agents.

The aim of this study was to genetically analyse Mycobacterium abscessus subsp. abscessus (hereafter M. abscessus) and M.

[Rapid mycobacterium identification and rapid susceptibility testing by the nucleic amplification method].

This review was designed to review mycobacterial infections from the viewpoint of clinical practices. We showed the usefulness of the rapid mycobacterium identification system for the detection of various genes by the nucleic amplification method. However, most PCR-based identifications required NALC-NaOH preprocessing, a special technique, or lengthy, hard work.

[Analysis of the clinical features of pulmonary disease caused by Mycobacterium szulgai].

Subjects & Methods: We reviewed the patient characteristics, radiological findings, treatments, and clinical outcomes in 12 cases of pulmonary Mycobacterium szulgai disease diagnosed at our hospital from April 1998 to March 2008. In addition, drug susceptibility testing of the causative isolates was performed with several antibiotics, including clarithromycin (CAM) and rifampicin (RFP), using BrothMIC NTM.

Results: The patients included 10 men and 2 women, with a mean age of 57.

[Molecular epidemiology of rifampicin mono-resistant Mycobacterium tuberculosis].

Purpose: We aimed to investigate the prevalence and possible transmission routes of rifampicin (RFP) mono-resistant Mycobacterium tuberculosis strains.

Methods: Drug susceptibility testing was used to identify 15 RFP-resistant strains out of 4633 M. tuberculosis isolates.

[Detection of molecular epidemiology of Mycobacterium gordonae isolates].

Objects: To analyze the molecular epidemiology of Mycobacterium gordonae strains from patients and environments in the hospital.

Subjects: A total of 46 clinical strains were obtained from patients registered at the NHO Kinki-chuo Chest Medical Center and 3 strains from hospital environments.

Methods: By using genetic data from the 16S rRNA gene and hsp65PRA, pulsed-field gel electrophoresis (PFGE) assessment of their intraspecies variability and epidemiology was carried out.

Comparison of rifabutin susceptibility and rpoB mutations in multi-drug-resistant Mycobacterium tuberculosis strains by DNA sequencing and the line probe assay.

We compared rifabutin susceptibility and rpoB mutations in 98 multi-drug-resistant strains of Mycobacterium tuberculosis (MDR-TB) by DNA sequencing and with a line probe assay using the commercially available INNO-LiPA Rif. TB kit (the LiPA). Our results indicated that rifabutin continues to remain active against MDR-TB strains harboring certain genetic alterations and also that the LiPA might be useful in identifying MDR-TB strains susceptible to rifabutin.

[Evaluation of the INNO-LiPA MYCOBACTERIA v2 for mycobacterial identification].

Purpose: Evaluation of the INNO-LiPA MYCOBACTERIA v2 (the INNO-LiPA assay) for mycobacterial identification.

Materials And Methods: The laboratory identifications consisting of Cobas Amplicor systems, AccuProbe, and DDH, are commonly used to identify mycobacterial isolates in Japan. We compared the results between the INNO-LiPA assay and the common methods.

[Evaluation of the discrepant Mycobacterium tuberculosis strains between any ordinary susceptibility testing and rpoB gene analysis by the line probe assay].

Purpose: Evaluation of rifampicin-resistance by the line probe assay, for rifampicin-susceptible Mycobacterium tuberculosis strains which were classified as rifampicin-resistant by the phenotypic drug susceptibility testings.

Materials And Methods: A total of 15 clinical isolates from NHO Kinki-chuo Chest Medical Center consisting of 6 rifampicin-resistant strains by the line probe assay despite susceptible result by the drug susceptibility testings, and 9 clinical isolates which showed the fluctuating results on repeated drug susceptibility testings. After we conducted 3 drug susceptibility testings and the line probe assay, we have examined the sequence analysis for confirming mutations in the rpoB gene.

[Comparison of BBL Mycoprep and 2%NaOH decontamination procedures for MGIT].

Objectives: We compared the BBL Mycoprep (Becton Dickinson Japan) and home-made 2%NaOH decontamination procedures by using an equal amount of expectorated sputum in the aerosol-free 30 ml KT centrifuge tube with the rugged inner surface.

Method: A total of 113 sputum specimens obtained in NHO Kinki-Chuo Chest Medical Center in November 2004 were subjected to two decontamination methods. All specimens were divided into two equal portions after concentrating the sediments processed by semi-kaline protease (SAP), then decontaminated, and inoculated into MGIT.

Hypervariable loci that enhance the discriminatory ability of newly proposed 15-loci and 24-loci variable-number tandem repeat typing method on Mycobacterium tuberculosis strains predominated by the Beijing family.

The newly proposed 15- and 24-loci mycobacterial interspersed repetitive unit (MIRU)-variable-number tandem repeat (VNTR) typing method was evaluated for its ability to differentiate 181 Mycobacterium tuberculosis Beijing family strains. Compared with the original 12-loci MIRU-VNTR typing method, the 15-loci system dramatically improved the discriminatory power for Beijing strains; however, large clusters that could be further differentiated by IS6110 restriction fragment length polymorphism (RFLP) were still obtained. The clonal stability and allelic diversity of a total of 31 VNTR loci were evaluated.

[Detection of rpoB mutations in rifampicin-resistant Mycobacterium kansasii].

Purpose: To detect rifampicin-resistant mutations in Mycobacterium kansasii (M. kansasii).

Methods: We examined the M.

Rapid detection of Mycobacterium tuberculosis in respiratory samples by transcription-reverse transcription concerted reaction with an automated system.

The aim of this study was to evaluate the performance of the transcription-reverse transcription concerted (TRC) method for the detection of Mycobacterium tuberculosis complex (MTC) 16S rRNA in clinical respiratory samples for the diagnosis of pulmonary tuberculosis. TRC is a novel method that enables the rapid and the completely homogeneous real-time monitoring of isothermal sequence RNA amplification without any postamplification procedure. The detection limit of the TRC method for MTC was one organism per 100 mul of sputum.

[A study on inoculum density and reproducibility of drug susceptibility testing by BACTEC MGIT 960].

Objective: The BACTEC MGIT 960 drug susceptibility system (MGIT AST) has been recently introduced in Japan. The issue of discordant MGIT results compared with the conventionally used Ogawa method has been raised. It has been speculated that discordant results might be due to MGIT inoculum density since there is no standardization step other than dilution of growth for tubes beyond 2 days after MGIT turns out to be positive.

[Present trends of drug-resistant tuberculosis and how to manage it by mycobacterial laboratories].

Global, domestic, and local trends of drug-resistant tuberculosis and how to manage increase in the resistance by mycobacterial laboratories were discussed based on literatures and our own data. At first, how to make drug-resistant tuberculosis was explained. Genetic drug-resistant bacteria were emerged spontaneously by mutation of the genome and were selected by inadequate treatment(mono-therapy or functional mono-therapy): acquired drug resistance(single, and then multi-drug resistance).