Association between Mycobacterium tuberculosis Beijing/W Lineage Strain Infection and Extrathoracic Tuberculosis: Insights from Epidemiologic and Clinical Characterization of the Three Principal Genetic Groups of M. tuberculosis Clinical Isolates

• Published in: Journal of Clinical Microbiology Vol. 45; no. 2; pp. 409 - 414
• Main Authors: Kong, Y, Cave, M.D, Zhang, L, Foxman, B, Marrs, C.F, Bates, J.H, Yang, Z.H
• Format: Journal Article
• Language: English
• Published: Washington, DC American Society for Microbiology 01-02-2007
• Subjects: Adolescent; Adult; Aged; Arkansas - epidemiology; Bacterial diseases; Bacterial Proteins - genetics; Biological and medical sciences; Child; Child, Preschool; China; DNA Transposable Elements; Fundamental and applied biological sciences. Psychology; Genotype; Human bacterial diseases; Human immunodeficiency virus; Humans; Infant; Infant, Newborn; Infectious diseases; Medical sciences; Microbiology; Middle Aged; Mycobacteriology and Aerobic Actinomycetes; Mycobacterium; Mycobacterium tuberculosis; Mycobacterium tuberculosis - classification; Mycobacterium tuberculosis - genetics; Mycobacterium tuberculosis - isolation & purification; Mycobacterium tuberculosis - pathogenicity; Polymorphism, Genetic; Sequence Analysis, DNA; Tuberculosis - epidemiology; Tuberculosis - microbiology; Tuberculosis - physiopathology; Tuberculosis and atypical mycobacterial infections; Type C Phospholipases - genetics; Virulence; Arkansas; China; Microbiology; Mycobacterial infection; Strain; Infection; Tuberculosis; Mycobacterium tuberculosis; Mycobacteriales; Bacteriosis; Mycobacteriaceae; Bacteria; Genetics; Actinomycetes; Clinical isolate
• ISSN: 0095-1137; 1098-660X; 1098-5530
• DOI: 10.1128/JCM.01459-06

Clinical strains of Mycobacterium tuberculosis can be divided into three principal genetic groups based on the single-nucleotide polymorphisms at the katG gene codon 463 and the gyrA gene codon 95. One subgroup of genetic group 1, the Beijing/W lineage, has been widely studied because of its worldwide distribution and association with outbreaks. In order to increase our understanding of the clinical and epidemiological relevance of the genetic grouping of M. tuberculosis clinical strains and the Beijing/W lineage, we investigated the genetic grouping of 679 clinical isolates of M. tuberculosis, representing 96.3% of culture-confirmed tuberculosis cases diagnosed in Arkansas between January 1996 and December 2000 using PCR and DNA sequencing. We assessed the associations of infections by different genetic groups of M. tuberculosis strains and infection by the Beijing/W lineage strains with the clinical and epidemiological characteristics of the patients using chi-square tests and multivariate logistic regression analysis. Of the 679 study isolates, 676 fell into one of the three principal genetic groups, with 63 (9.3%) in group 1, 438 (64.8%) in group 2, and 175 (25.9%) in group 3. After adjusting for potential confounding of age, gender, race/ethnicity, human immunodeficiency virus serostatus, and plcD genotype in a multivariate logistic regression model, patients infected by the Beijing/W lineage isolates were nearly three times as likely as patients infected with the non-Beijing/W lineage isolates to have an extrathoracic involvement (odds ratio [95% confidence interval], 2.85 [1.33, 6.12]). Thus, the Beijing/W lineage strains may have some special biological features that facilitate the development of extrathoracic tuberculosis.