Browsing by Author "Çavusoglu, C"

Now showing 1 - 8 of 8
  • No Thumbnail Available
    Item
    Antimicrobial Resistance Patterns of Mycobacterium abscessus Complex Clinical Isolates
    Sürücüoglu, S; Özkütük, N; Gazi, H; Çavusoglu, C
    Objective:This study aimed to identify subspecies of Mycobacterium abscessus complex (MABC) isolates from clinical samples by a molecular technique and to determine mutations responsible for macrolide and aminoglycoside resistance. We also aimed to investigate the correlation of phenotypic and molecular test results by examining the resistance to antimicrobial agents according to CLSI standard using the liquid microdilution test. Methods: 27 MABC isolates from clinical samples were examined. Molecular subspecies identification and mutations responsible for aminoglycoside (rrs mutation) and macrolide resistance (rrl mutation) were determined using the GenoType NTM-DR test. The resistance phenotypes of the strains to various antimicrobial agents were investigated by the Sensititre (TM) RAPMYCOI AST microdilution test. Results: Of the 27 isolates tested, 21 were M. abscessus subsp. abscessus, three were M. abscessus subsp. bolletii, and three were M. abscessus subsp. massiliense; rrs and rrl mutations were not observed in any strains. Except for one isolate, all M. abscessus subsp. abscessus strains showed the erm(41) T28 genotype, which indicates inducible macrolide resistance. The correlation between the GenoType NTM-DR and phenotypic susceptibility test results was 81% (k=0.5, p=0.02) for inducible macrolide resistance and 89% for acquired macrolide resistance. The most effective antimicrobial agents were amikacin, cefoxitin, imipenem, linezolid, and tigecycline. Conclusion: Although the GenoType NTM-DR test is reliable in identifying and detecting molecular macrolide and aminoglycoside resistance, there were discrepancies in the results. We recommend confirming the results with the phenotypic susceptibility method after growth on culture. Although the M. abscessus complex is resistant to many antimicrobial agents, it has shown high sensitivity to amikacin, cefoxitin, imipenem, linezolid, and tigecycline. High levels of inducible macrolide resistance in isolates indicate the importance of subtyping and sensitivity testing of iso-lates in patients where culture conversion has not been achieved.
  • No Thumbnail Available
    Item
    First isolation of Mycobacterium bovis SIT 482 BOV from beef cattle in Turkey
    Avsever, ML; Çavusoglu, C; Çamkerten, I
    Bovine tuberculosis is a zoonotic disease which should be emphasized in our country as in many countries. A large number of genotypes have been revealed by spoligotyping method of M . bovis in the world. M bovis SIT 482. BOV is one of these genotypes and it is also M. bovis genotype in which BCG vaccine is administered in humans. The BCG vaccine is obtained through multiple passages of this genotype. However, this genotype, like other genotypes, can cause serious infections in humans and animals. There are data on the isolation of M. bovis SIT 482 BOV from animal and human tuberculosis cases in the world. In our country, the isolation of this genotype has been reported only in humans and no data have been found in the animals. In this study, M. bovis SIT 482. BOV was isolated from the samples of six cattle with internal organ samples obtained from licensed slaughterhouses in Aksaray. While isolation is carried out with BACTEC MGIT 960 liquid media, spoligotyping was carried out according to the manufacturer's with kit (Isogen LifeScience, The Netherlands). This study aims to report M. bovis SIT 482 BOV from cattle in Turkey for the first time, to draw attention a very limited number reported in M. bovis cases in Turkey, highlight the importance of genotyping of tuberculosis factors and contribute to epidemiological studies. These and similar studies will contribute to the creation of genetic maps for eradication of M. bovis from cattle in our country. The study was also conducted to investigate whether M bovis SIT 482. BOV isolated from cattle in Aksaray province is BCG strain or another strain giving the same pattern.
  • No Thumbnail Available
    Item
    Chronic subcutaneous nodules, plaques and ulcers of the hand
    Ermertcan, AT; Özkütük, N; Temiz, P; Çavusoglu, C; Sürücüoglu, S
  • No Thumbnail Available
    Item
    In vitro Activity of Rifabutin and Clofazimine to Macrolide- Resistant Mycobacterium abscessus Complex Clinical Isolates
    Sürücüoglu, S; Özkütük, N; Gazi, H; Çavusoglu, C
    Mycobacterium abscessus complex (MABSC) is one of the most resistant bacteria against antimicrobial agents. The number of agents that can be used by oral route, such as macrolides, is limited in antimicro- bial therapy. In recent years, rifabutin and clofazimine have gained importance as they can be admin- istered by oral route and have shown synergistic effects with macrolides and aminoglycosides. The aim of this study was to determine the in vitro activity of rifabutin and clofazimine against clinical isolates of MABSC resistant to macrolides. A total of 48 MABSC isolates obtained from respiratory tract and other clinical samples in the Tuberculosis Laboratories of the Faculty of Medicine of Manisa Celal Bayar and Ege Universities were included in the study. Subspecies differentiation and aminoglycoside and macrolide resistance of the isolates were determined by GenoType NTM-DR test. Rifabutin and clofazimine sus- ceptibilities were determined by standard broth microdilution method. Of the MABSC isolates 42 were identified as M.abscessus subsp. abscessus, three as M.abscessus subsp. bolletii and three as M.abscessus subsp. massiliense. None of the isolates exhibited rrs and rrl mutations indicating acquired macrolide resistance and aminoglycoside resistance. However, the erm(41) T28 genotype which is associated with inducible macrolide resistance was detected in 41 (85%) of the strains. All M.abscessus subsp. massiliense isolates were found to be genotypically susceptible to macrolides. The minimum inhibitory concentration (MIC) range values for rifabutin were 0.0625 to 32 mu g/mL, while for clofazimine, the range was 0.0625 to 1 mu g/mL. Rifabutin MIC values were significantly higher (mean 5.98 mu g/mL vs 0.5 mu g/mL, p= 0.026) in the isolates with macrolide resistance. There was no correlation between macrolide resistance and clofazimine MIC values (mean 0.25 mu g/mL vs. 0.214 mu g/mL, p= 0.758). The MIC50 and MIC90 values for rifabutin were 1 and 8 mu g/mL, respectively, while for clofazimine they were 0.25 and 0.5 mu g/mL. Macrolide resistance was found to be higher in isolates with rifabutin MIC values above the MIC50 value (p= 0.045). In conclusion, the determination of higher rifabutin MIC values in isolates resistant to macrolides suggested that susceptibility testing should be performed before adding rifabutin to the treatment regimen. The low MIC values of clofazimine in all strains indicated that it may be used as a first choice in the combination therapy. However, further studies using a larger number of clinical isolates and applying genotypic and phenotypic susceptibility tests are needed to determine threshold MIC values to assist clinicians in treatment decisions.
  • No Thumbnail Available
    Item
    Development of a database for tracking HIV positive/aids patients
    Altuglu, I; Çavusoglu, C; Çiçek, C; Tünger, O
    The collection of reliable data is the first step to assess the status of HIV/AIDS in a community. HIV recording systems are necessary for organizing and analyzing the patients' data. The aim of the study was to develop a database to be used to track HIV positive/AIDS patients. The database includes general demographic fields as well as specific fields such as health history, laboratory and other clinical history, current and past drug regimens (both antiretroviral and non-antiretroviral drugs). It is also possible to organize and maintain a patient database according to specific diseases, laboratory tests and/or medication treatments.
  • No Thumbnail Available
    Item
    Evaluation of the performance of MALDI-TOF MS and DNA sequence analysis in the identification of mycobacteria species
    Akyar, I; Çavusoglu, C; Ayas, M; Sürücüoglu, S; Ilki, A; Kaya, DE; Besli, Y
    Background/aim: Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is an alternative way of identifying mycobacteria via the analysis of biomolecules. It is being increasingly used in routine microbiology practice since it permits early, rapid, and cost-effective identification of pathogens of clinical importance. In this study, we aimed to evaluate the efficacy of phenotypic identification of mycobacteria by the MALDI-TOF MS MBT Mycobacteria Library (ML) 4.0 (Bruker, Daltonics) compared to standard sequence analysis. Materials and methods: A total of 155 Mycobacterium clinical and external quality control isolates, comprising nontuberculous mycobacteria (NTM) (n = 95) and the Mycobacterium tuberculosis complex (MTC) (n = 60), were included in the study. Results: Identification by MBT ML4.0 was correctly performed in 100% of MTC and in 91% of NTM isolates. All of the MTC isolates were correctly differentiated from NTM isolates. Conclusion: Based on our results, MBT ML4.0 may be used reliably to identify both NTM and MTC.
  • No Thumbnail Available
    Item
    Investigation of Extensive Drug Resistance in Multidrug Resistance Tuberculosis Isolates
    Bektöre, B; Haznedaroglu, T; Baylan, O; Özyurt, M; Özkütük, N; Satana, D; Çavusoglu, C; Seber, E
    Increasing number of drug resistant tuberculosis (TB) cases, observed in recent years, is an important public health problem. Extensively drug resistant TB (XDR-TB) is the development of resistance against any fluoroquinolones and at least one of the injectable second line anti-TB drugs in addition to resistance against isoniazide and rifampicin which are the first line anti-TB drugs [definition of multidrug resistant TB (MDR-TB)]. Anti-TB therapy failed with first-line anti-TB drugs due to MDR-TB cases is being planned according to second-line anti-TB drug susceptibility test results if available and if not, standart treatment protocols are used. Although it is recommended that individual anti-TB therapy should be designed according to the isolate's susceptibility test results, standart therapeutic protocols are always needed since second-line anti-TB drug susceptibility testing generally could not be performed in developing countries like Turkey. For this reason, nationwide and regional surveillance studies to determine the resistance patterns are always needed to make decisions about the standard therapy algorithms. In this study, it was aimed to investigate the presence of extensive drug resistance among 81 MDR-TB isolates obtained from various health care facilities from Istanbul, Izmir and Manisa and to determine the XDR-TB incidence in Marmara and Aegean regions. Furthermore, we aimed to provide epidemiological data to clinicians to support their choice of second-line anti-TB drugs for MDR-TB infections. Susceptibility testing of isolates for the first and the second-line anti-TB drugs were performed by using modified Middlebrook 7H9 broth in fluorometric BACTEC MGIT 960 system (Becton Dickinson, USA). Eighty-one MDR-TB isolates included in this study were isolated from 43 (53.1%) patients residing in Istanbul, 26 (32.1%) in Izmir and 12 (14.8%) in Manisa provinces. We could not find any isolate consistent with XDR-TB definition in this study. Second-line drug resistance rates of MDR-TB isolates to amikacin and kanamycin were 1.2%, ofloxacin and levofloxacin were 2.5%, capreomycin was 14.8%, ethionamide was 37% whereas linezolid resistance was not detected. Statistically significant correlation was detected between resistance rates of these antibiotic pairs; levofloxacin-ofloxacin (p< 0.01), amikacin-kanamycin (p= 0.01) and streptomycin-ethionamide (p= 0.04). In our study, extensive drug resistance was not encountered in any MDR-TB isolates while high resistance rates was observed against ethionamide and capreomycin. It can be concluded that parenteral aminoglycosides amikasin and kanamycin, fluoroquinolones and linezolid seemed to be reliable anti-TB agents in MDR-TB treatment, however, further larger scale studies are needed.
  • No Thumbnail Available
    Item
    Distribution of Nontuberculous Mycobacteria Isolated from Clinical Specimens and Identified with DNA Sequence Analysis
    Özçolpan, OO; Sürücüoglu, S; Özkütük, N; Çavusoglu, C
    The aims of the study were to perform the identification of nontuberculous mycobacteria (NTM) isolated from different clinical specimens in the Mycobacteriology Laboratory of Celal Bayar University, Manisa (located at Aegean region of Turkey), by DNA sequence analysis, and to discuss the epidemiological aspects of the data obtained. Out of 5122 clinical specimens sent to the laboratory with the initial diagnosis of tuberculosis in the period April 2007 to July 2011, M.tuberculosis complex and NTM were identified in 225 (4.39%) and 126 (2.46%) samples, respectively. DNA sequence analysis by targeting hsp65 and 16S rDNA gene regions was performed on 101 of the NTM strains in Mycobacteriology Laboratory of Ege University, Izmir. DNA sequence analysis data was evaluated using RIDOM and GenBLAST data bases. NTM strains were identified as 40 M.porcinum (39.60%), 36 M.lentiflavum (35.65%), six M.abscessus (5.64%), five M.peregrinum (4.95%), four M.gordonae (3.96%), three M.fortuitum (2.97%), two M.chelonae (1.98%), and one for each M.alvei (0.99%), M.scrofulaceum (0.99%), M.kansasii (0.99%) species. Two strains which were both 95-98% compatible with other mycobacteria in the data bases could not be identified with certainty. Seventy-two (94.73%) strains of M.lentiflavum and M.porcinum, which were the most frequent (75.24%) species in the study, were isolated from bronchoalveolar lavage (BAL) specimens. The remaining 99 strains examined could not be proven as the cause of the disease due to absence of patients' clinical data, whereas two M.abscessus strains isolated from the sputum were considered as the cause of the disease according to the ATS/IDSA criteria. The isolation rate of NTM in 2010 was found significantly higher (5.33%) than previous years. Review of the 2010 data showed that all strains of M.porcinum and M.lentiflavum, which were the most frequently identified strains were isolated from BAL specimens. This situation is in line with the start of using of an automatic bronchoscope washing machine in our hospital in the same year. In conclusion, NTM were isolated in 2.46% of the clinical specimens of the patients with the initial diagnosis of tuberculosis and these strains belonged to 10 different NTM species. The two NTM species most frequently isolated in our study were M.lentiflavum and M.porcinum which are known for their potential to cause human infections and antibiotic resistance. As these strains were mostly isolated in BAL specimens, it is concluded that automatic bronchoscope washing machines and water delivery system in the hospitals should be examined in terms of contamination by NTM. The isolated NTM strains could not be distinguished as the cause of the disease or a contaminant, which is the limiting factor in this study. However, knowing that the environmental mycobacteria can cause hospital infections, the data obtained in this study can contribute to epidemiology of NTM infections in Turkey.