Whole-Genome Sequence of Mycobacterium tuberculosis Korean Strain KIT87190.

Mycobacterium tuberculosis is a contagious agent that causes tuberculosis. A specific type (called the K cluster) of M. tuberculosis with 10 copies of IS6110 in restriction fragment length polymorphism (RFLP) has been found in about 4% of M.

Detection and assessment of clarithromycin inducible resistant strains among Korean Mycobacterium abscessus clinical strains: PCR methods.

Background: Mycobacterium abscessus group belongs to a group of rapidly growing mycobacteria (RGM) and, following Mycobacterium avium complex, is the second most common pathogen responsible for lung disease caused by nontuberculous mycobacteria (NTM). Clarithromycin is known to be the key drug in the treatment of M. abscessus group disease, but a high failure rate of treatment response is reported due to clarithromycin inducible resistance.

Optimal Combination of VNTR Typing for Discrimination of Isolated Mycobacterium tuberculosis in Korea.

Background: Variable-number tandem repeat (VNTR) typing is a promising method to discriminate the Mycobacterium tuberculosis isolates in molecular epidemiology. The purpose of this study is to determine the optimal VNTR combinations for discriminating isolated M. tuberculosis strains in Korea.

The drug resistance profile of Mycobacterium abscessus group strains from Korea.

Background: Bacteria of the Mycobacterium abscessus group are the second most common pathogens responsible for lung disease caused by nontuberculous mycobacteria in Korea. There is still a lack of studies investigating the genetic mechanisms involved in M. abscessus resistance to antibiotics other than clarithromycin.

Use of the VNTR typing technique to determine the origin of Mycobacterium tuberculosis strains isolated from Filipino patients in Korea.

With increasing international interchange of personnel, international monitoring is necessary to decrease tuberculosis incidence in the world. This study aims to develop a new tool to determine origin of Mycobacterium tuberculosis strains isolated from Filipino patients living in Korea. Thirty-two variable number tandem repeat (VNTR) loci were used for discrimination of 50 Filipino M.

Mycobacterium massiliense induces inflammatory responses in macrophages through Toll-like receptor 2 and c-Jun N-terminal kinase.

Mycobacterium massiliense (Mmass) is an emerging, rapidly growing mycobacterium (RGM) that belongs to the M. abscessus (Mabc) group, albeit clearly differentiated from Mabc. Compared with M.

Intra-subspecies sequence variability of the MACPPE12 gene in Mycobacterium avium subsp. hominissuis.

The PE (Pro-Glu) and PPE (Pro-Pro-Glu) multigene families are unique to mycobacteria, and are highly expanded in the pathogenic members of this genus. We determined the intra-subspecies genetic variability of the MACPPE12 gene, which is a specific PPE gene in Mycobacterium avium subsp. hominissuis (MAH), using 334 MAH isolates obtained from different isolation sources (222 human isolates, 145 Japanese and 77 Korean; 37 bathroom isolates; and 75 pig isolates).

Evaluation of MGIT 960 System for the Second-Line Drugs Susceptibility Testing of Mycobacterium tuberculosis.

Many laboratories validate DST of the second-line drugs by BACTEC MGIT 960 system. The objective of this study is to evaluate the critical concentration and perform DST for the 2nd line drugs. We evaluated 193 clinical strains of M.

Increased tuberculosis burden due to demographic transition in Korea from 2001 to 2010.

Background: Notified tuberculosis (TB) cases in Korea have not decreased over the last decade (2001-2010).

Methods: To clarify the reasons, we analyzed an annual report on notified tuberculosis patients and age-specific population drift in Korea.

Results: Compared to the age-specific notified TB cases between 2001 and 2010, distinctive features in notified TB cases and new cases increased markedly in people aged 45-54 years and in patients over 65 years old, whereas those between 15-34 years in 2010 decreased drastically.

Characterization of mutations in multi- and extensive drug resistance among strains of Mycobacterium tuberculosis clinical isolates in Republic of Korea.

In order to characterize molecular mechanisms of first- and second-line drug resistance in Mycobacterium tuberculosis and to evaluate the use of molecular markers of resistance, we analyzed 62 multidrug-resistant, 100 extensively drug-resistant, and 30 pan-susceptible isolates from Korean tuberculosis patients. Twelve genome regions associated with drug resistance, including katG, ahpC, and inhA promoter for isoniazid (INH); embB for ethambutol (EMB), rpoB for rifampin (RIF), pncA for pyrazinamide (PZA), gyrA for fluoroquinolones; rpsL, gidB, and rrs for streptomycin; rrs and eis for kanamycin (KM); rrs and tylA for capreomycin (CAP); and rrs for amikacin (AMK) were amplified simultaneously by polymerase chain reaction, and the DNA sequences were determined. We found mutations in 140 of 160 INH-resistant isolates (87.

Molecular genetics of Mycobacterium tuberculosis resistant to aminoglycosides and cyclic peptide capreomycin antibiotics in Korea.

Aminoglycosides are key drugs for the treatment of multidrug-resistant tuberculosis. A total of 97 extensively drug-resistant (XDR) and 29 pan-susceptible Mycobacterium tuberculosis isolates from Korean tuberculosis patients were analyzed to characterize mutations within the rrs, rpsL, gidB, eis and tlyA genes. Thirty (56.

Mycobacterium wolinskyi infection confirmed by rpoB gene sequencing.

Identification of rapidly growing mycobacteria (RGM) is problematic because there are many taxonomic changes. 16S rRNA gene is commonly used to identify Mycobacterium species, but alternative gene targets have been introduced for more accurate identification. We report a rare case of a prosthetic knee infection due to Mycobacterium wolinskyi.

Host cell autophagy activated by antibiotics is required for their effective antimycobacterial drug action.

The current standard of treatment against tuberculosis consists of a cocktail of first-line drugs, including isoniazid and pyrazinamide. Although these drugs are known to be bactericidal, contribution of host cell responses in the context of antimycobacterial chemotherapy, if any, remains unknown. We demonstrate that isoniazid and pyrazinamide promote autophagy activation and phagosomal maturation in Mycobacterium tuberculosis (Mtb)-infected host cells.

Correlation of the phenotypic ethambutol susceptibility of Mycobacterium tuberculosis with embB gene mutations in Korea.

The phenotypic resistance to ethambutol (EMB) in Mycobacterium tuberculosis with embB gene mutations is still unclear. This study was designed to better understand EMB resistance due to embB gene mutation. Sequencing analysis of the embB gene was performed for 124 EMB-susceptible and 93 EMB-resistant M.

Clustering of Mycobacterium tuberculosis strains from foreign-born patients in Korea.

Information on drug resistance and transmission patterns of tuberculosis (TB) in foreign-born patients is lacking in Asia where immigration is increasing. We examined the drug-resistance profiles of 288 Mycobacterium tuberculosis isolates from foreign-born patients in South Korea, and assessed for potential transmission in the host country by analysing their IS6110 genotypes, as well as those of 4780 strains from native Korean TB patients. The prevalence of multidrug-resistant (MDR) TB was 9.

First case of Segniliparus rotundus pneumonia in a patient with bronchiectasis.

We report the first case of Segniliparus rotundus pneumonia in an adult with non-cystic fibrosis bronchiectasis. All isolates were identified as S. rotundus by 16S rRNA gene sequencing and rpoB PCR-restriction analysis.

Polymerase chain reaction-restriction fragment length polymorphism of the rpoB gene for identification of Mycobacterium avium subsp. paratuberculosis and differentiation of Mycobacterium avium subspecies.

Mycobacterial speciation by polymerase chain reaction (PCR)-restriction fragment length polymorphism analysis (PRA) of the rpoB gene was evaluated for identification of Mycobacterium avium subsp. paratuberculosis (MAP) and other Mycobacterium avium complex (MAC) members to the species or subspecies level by comparison with conventional methods including hsp65 sequencing, high-performance liquid chromatography, and PCR for accepted species- or subspecies-specific genomic targets. A total of 185 type and clinical mycobacterial strains from humans, animals, and environments were tested.

Isolation and characterizations of clarithromycin-resistant Mycobacterium avium clinical isolates.

Mycobacterium avium is an important intracellular pathogen, particularly in AIDS patients. It also shows the second frequency among nontuberculous mycobacteria infections in Korea. Point mutations of domain V region of the 23S rRNA gene has been known to confer clarithromycin resistance to M.

Clinical significance of differentiation of Mycobacterium massiliense from Mycobacterium abscessus.

Rationale: Mycobacterium massiliense has been recognized as a separate species from Mycobacterium abscessus; however, little is known regarding the clinical impact of this differentiation.

Objectives: To compare clinical features and treatment outcomes between patients with M. abscessus lung disease and those with M.

Phylogeographical particularity of the Mycobacterium tuberculosis Beijing family in South Korea based on international comparison with surrounding countries.

To understand the domestic population structure of Mycobacterium tuberculosis clinical isolates in the Republic of Korea, we genotypically analysed 80 isolates obtained from various geographical origins in the country. Of these, 64 (80.0 %) isolates were identified as Beijing family strains.

Antibiotic treatment of Mycobacterium abscessus lung disease: a retrospective analysis of 65 patients.

Rationale: The optimal therapeutic regimen and duration of treatment for Mycobacterium abscessus lung disease is not well established.

Objectives: To assess the efficacy of a standardized combination antibiotic therapy for the treatment of M. abscessus lung disease.

Clarithromycin susceptibility testing of Mycobacterium avium complex using 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride microplate assay with Middlebrook 7H9 broth.

A series of 119 Mycobacterium avium complex isolates were subjected to clarithromycin susceptibility testing using microplates containing 2,3-diphenyl-5-thienyl-(2)-tetrazolium chloride (STC). Among 119 isolates, 114 (95.8%) were susceptible to clarithromycin and 5 were resistant according to the new and the standard method.

Spread of nontuberculous mycobacteria from 1993 to 2006 in Koreans.

In Korea, the prevalence of nontuberculous mycobacterial (NTM) pulmonary disease has risen, observed primarily in immunocompetent patients with or without preexisting lung disease. The purpose of this study was to determine the frequency of various species of NTM isolates from respiratory specimens in a single institution over a 14-year period in Korea. All samples referred to our reference laboratory over a 14-year period in Korea were analyzed.

In vitro antimicrobial susceptibility of Mycobacterium abscessus in Korea.

Mycobacterium abscessus is the second most common etiology of pulmonary disease caused by nontuberculous mycobacteria in Korea. Although antimicrobial susceptibility tests are important for appropriate patient management in M. abscessus lung disease, the tests have never been investigated in Korea.