Distribution of Spoligotyping Defined Genotypic Lineages among Drug-Resistant Mycobacterium tuberculosis Complex Clinical Isolates in Ankara, Turkey

Background: Investigation of genetic heterogeneity and spoligotype-defined lineages of drug-resistant Mycobacterium tuberculosis clinical isolates collected during a three-year period in two university hospitals and National Tuberculosis Reference and Research Laboratory in Ankara, Turkey. Methods and Findings: A total of 95 drug-resistant M. tuberculosis isolates collected from three different centers were included in this study. Susceptibility testing of the isolates to four major antituberculous drugs was performed using proportion method on Löwenstein–Jensen medium and BACTEC 460-TB system. All clinical isolates were typed by using spoligotyping and IS6110-restriction fragment length polymorphism (RFLP) methods. Seventy-three of the 95 (76.8%) drug resistant M. tuberculosis isolates were isoniazid-resistant, 45 (47.4%) were rifampicin-resistant, 32 (33.7%) were streptomycinresistant and 31 (32.6%) were ethambutol-resistant. The proportion of multidrug-resistant isolates (MDR) was 42.1%. By using spoligotyping, 35 distinct patterns were observed; 75 clinical isolates were grouped in 15 clusters (clustering rate of 79%) and 20 isolates displayed unique patterns. Five of these 20 unique patterns corresponded to orphan patterns in th

Comparison and Evaluation of Lowenstein-Jensen Medium and 2% Ogawa Medium for the Diagnosis of Tuberculosis

WOS: 000300746300005PubMed ID: 22399169Accurate diagnosis of tuberculosis is based on the detection of the bacilli in the clinical specimen. The growth of mycobacteria in laboratory media is regarded as the gold standard for diagnosis and use of two different cultivation media, one of them being a liquid one, is recommended. In this study, the diagnostic values of egg-based Lowenstein-Jensen (11) medium used extensively all over the world and Ogawa (2%) medium were compared. A total of 7912 pulmonary and extrapulmonary clinical samples which belonged to 3311 patients with suspected tuberculosis, were enrolled in the National Tuberculosis Reference Laboratory in Refik Saydam National Public Health Agency during 2.5 years (January 2006-June 2008). The samples were processed by modified Petroff method (4% NaOH) for homogenization-decontamination-concentration on the same day and inoculated on two Ogawa and two LJ media. The cultures were incubated at 35-37 degrees C for eight weeks and were controlled on the third day of incubation in terms of contamination. If no contamination were detected, the cultures were incubated for a total of eight weeks with regular weekly controls. The colonies detected in culture media were identified by biochemical tests, including paranitrobenzoic acid (PNB), niacin accumulation and nitrate reduction tests. Those indentified as Mycobacterium tuberculosis complex were reported as positive. The rates of contamination was 3.1% for Ogawa medium and 4% for 11 medium. Culture results were found positive for 248 patients (7.5%). While 210 of these were positive by both of the media, 20(8.1%) patients were detected positive only by LJ and 18 (7.3%) only by Ogawa medium. The sensitivity of LJ medium was 92.7% (230/248) and of Ogawa medium was 91.9% (228/248). When LJ medium was taken as the reference method, the sensitivity, specificity, positive and negative predictive values of Ogawa medium were 91.3%, 99.4%, 92.1% and 99.4%, respectively. It was concluded that, when low price and low contamination rates were taken into consideration, Ogawa medium, used together with a liquid medium + LJ medium, would increase the yield of mycobacteria from single samples (cerebrospinal fluid, biopsy, pus, etc.) sent to the laboratories

Description of 30 shared types containing 90 isolates that matched a preexisting shared type in the SITVIT2 proprietary database of the Pasteur Institute of Guadeloupe.

a<p>The percentage in this study as compared to the SITVIT2 database was calculated by dividing the number of strains with a given pattern in the present study by the total number of strains with the same pattern in the database, and then multiplying the figure by 100 to get the percentage with respect to the total amount. Note that SITVIT2 is an updated version of the previously released SpolDB4 database <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0030331#pone.0030331-Brudey1" target="_blank">[27]</a>. At the time of the present analysis, it contained genotyping information on 67,000 <i>M. tuberculosis</i> clinical isolates from 160 countries of patient origin.</p>b<p>Lineage designation, LAM: Latin-American and Mediterranean; Unk: Unknown patterns within any of the major lineage described in database.</p>c<p>For newly created SITs, match with an orphan isolate is shown in the database.</p

Drug resistance patterns of the 95 drug-resistant <i>M. tuberculosis</i> isolates from Ankara, Turkey.

<p>Drug resistance patterns of the 95 drug-resistant <i>M. tuberculosis</i> isolates from Ankara, Turkey.</p

Statistical comparison of Beijing isolates in this study and in the previously published studies from Turkey.

<p>Statistical comparison of Beijing isolates in this study and in the previously published studies from Turkey.</p

Description of the orphan isolates (n = 5) after comparison of the spoligotype patterns of the drug-resistant <i>M. tuberculosis</i> isolates from Ankara with the SITVIT2 database.

<p>Description of the orphan isolates (n = 5) after comparison of the spoligotype patterns of the drug-resistant <i>M. tuberculosis</i> isolates from Ankara with the SITVIT2 database.</p