Genetic variation of Mycobacterium tuberculosis circulating in Kharkiv Oblast, Ukraine

<p>Abstract</p> <p>Background</p> <p>A persistent increase of tuberculosis cases has recently been noted in the Ukraine. The reported incidence of drug-resistant isolates of <it>M. tuberculosis </it>is growing steadily; however, data on the genetic variation of isolates of <it>M. tuberculosis </it>circulating in northern Ukraine and on the spectrum and frequency of occurrence of mutations determining resistance to the principal anti-tuberculosis drugs isoniazid and rifampicin have not yet been reported.</p> <p>Methods</p> <p>Isolates of <it>M. tuberculosis </it>from 98 tuberculosis patients living in Kharkiv Oblast (Ukraine) were analyzed using VNTR- and RFLP-IS6110-typing methods. Mutations associated with resistance to rifampicin and isoniazid were detected by RFLP-PCR methods, and also confirmed by sequencing.</p> <p>Results</p> <p>We identified 75 different genetic profiles. Thirty four (34%) isolates belonged to the Beijing genotype and 23 (23%) isolates belonged to the LAM family. A cluster of isolates belonging to the LAM family had significant genetic heterogeneity, indicating that this family had an ancient distribution and circulation in this geographical region. Moreover, we found a significant percentage of the isolates (36%) belonged to as yet unidentified families of <it>M. tuberculosis </it>or had individual non-clustering genotypes. Mutations conferring rifampicin and isoniazid resistance were detected in 49% and 54% isolates, respectively. Mutations in codon 531 of the <it>rpoB </it>gene and codon 315 of the <it>katG </it>gene were predominant among drug-resistant isolates. An association was found for belonging to the LAM strain family and having multiple drug resistance (R = 0.27, p = 0.0059) and also for the presence of a mutation in codon 531 of the <it>rpoB </it>gene and belonging to the Beijing strain family (R = 0.2, p = 0.04).</p> <p>Conclusions</p> <p>Transmission of drug-resistant isolates seems to contribute to the spread of resistant TB in this oblast. The Beijing genotype and LAM genotype should be seen as a major cause of drug resistant TB in this region.</p

Molecular characterization of AmpC β-lactamases among Klebsiella pneumoniae isolated from Ilam and Tehran hospitals, from Iran

The common use of beta lactam antibiotics for tratment of bacteria infections leads to increase the world wide microbial resistance by producing beta lactamase enzyme among clinical isolates. In recent years, the production of broad-spectrum beta-lactamase enzymes in clinical isolates, especially E.coli and Klebsiella bacteria are common. Typical Ampc enzymes (class C- ESBLs) confirm resistance to most oxyimino cephalosporins. The aim of this study is to determine the prevalence of AmpC type extended spectrum beta lactamases genes in clinical isolates of Klebsiella pneumoniae. 108 clinical sample of K.pneumoniae, isolated from hospitalized patients procured from two hospitals in Ilam and Tehran. To identify Ampc genes, PCR method was used. 95/3 percent of isolates were resistant to Cefoxitin, 49 isolates were positive for FOXM cluster genes, 35 were positive for DHAM cluster genes and 6 were positive for CITM cluster genes. Our results showed that among of clinical isolates of Klebsiella pneumoniae, prevalence broad-spectrum beta-lactamase enzymes and Ampc genes are relatively high

Comparison between molecular epidemiology, geographical regions and drug resistance in Mycobacterium tuberculosis strains isolated from Iranian and Afghan patients

The aim of this study was to determine the prevalence of drug-resistant tuberculosis (TB) and its associated risk factors. The susceptibilities of Mycobacterium tuberculosis isolates were tested against four first-line antituberculous drugs and were typed by spoligotyping. Spoligotyping of M. tuberculosis strains resulted in 95 different patterns that were divided into three evolutionary groups (1-3). Eighty-six (90) of the isolates had unique patterns that were reported for the first time. Interestingly, 9.4 of the strains belonged to the Beijing family. Multidrug resistance (MDR) was seen in group 1 of the evolutionary scenario. All M. tuberculosis isolates belonging to the Beijing family were associated with a resistance pattern. MDR was much higher in bacteria isolated from Afghan TB patients residing in Iran. Copyright © 2006 S. Karger AG