A country-wide study of spoligotype and drug resistance characteristics of Mycobacterium tuberculosis isolates from children in China

PLoS One. 2013 Dec 30;8(12):e84315. doi: 10.1371/journal.pone.0084315. eCollection 2013.

Abstract

Background: Tuberculosis (TB) is still a big threat to human health, especially in children. However, an isolation of Mycobacterium tuberculosis culture from pediatric cases remains a challenge. In order to provide some scientific basis for children TB control, we investigated the genotyping and drug resistance characteristics of M. tuberculosis isolates from pediatric cases in China.

Methodology/principal findings: In this study, a total of 440 strains including 90 from children (<15 years), 159 from adolescents (15-18 years) and 191 from adults (>18 years) isolated in 25 provinces across China were subjected to spoligotyping and drug susceptibility testing. As a result, Beijing family strains were shown to remain predominant in China (85.6%, 81.1% and 75.4% in three above groups, respectively), especially among new children cases (91.0% vs. 69.6% in previously treated cases, P=0.03). The prevalence of the Beijing genotype isolates was higher in northern and central China in the total collection (85.1% in northern and 83.9% in central vs. 61.6% in southern China, P<0.001) and a similar trend was seen in all three age groups (P=0.708, <0.001 and 0.025, respectively). In adolescents, the frequencies of isoniazid (INH)-resistant and ethambutol (EMB)-resistant isolates were significantly higher among Beijing strains compared to non-Beijing genotype strains (P=0.028 for INH and P=0.027 for EMB). Furthermore, strong association was observed between resistance to rifampicine (RIF), streptomycin (STR) and multidrug resistance (MDR) among Beijing compared to non-Beijing strains in previously treated cases of children (P=0.01, 0.01 and 0.025, respectively).

Conclusion/significance: Beijing family was more prevalent in northern and central China compared to southern China and these strains were predominant in all age groups. The genetic diversity of M. tuberculosis isolates from children was similar to that found in adolescents and adults. Beijing genotype was associated with RIF, STR and MDR resistance in previously treated children.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Antitubercular Agents / pharmacology*
  • Child
  • China / epidemiology
  • Female
  • Genotype
  • Geography
  • Humans
  • Male
  • Molecular Typing*
  • Mycobacterium tuberculosis / drug effects
  • Mycobacterium tuberculosis / genetics*
  • Mycobacterium tuberculosis / isolation & purification*
  • Mycobacterium tuberculosis / physiology

Substances

  • Antitubercular Agents

Grants and funding

This study was supported by the Capital Health Research and Development of Special Grant (No. 2011-1007-01, No. 2011-2009-05), National Science and Technology Major Project of China (2013ZX10003003), Open Project of Beijing Key Laboratory of Capital Medical University (2013NYJH02) and National Natural Science Foundation of China (No. 81271889). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.