Mikrobiyol Bul
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Infections caused by extended-spectrum beta-lactamase (ESBL) producing Escherichia coli and Klebsiella spp. constitute severe problems. Carbapenems are commonly used to treat these infections. However, infections caused by carbapenem-resistant gram-negative bacteria show an increasing trend recently. ⋯ While two Klebsiella spp. İsolates were resistant to all of the tested carbapenems (MIC > 32 µg/ml), two E.coli isolates were resistant to ertapenem (MIC > 32 µg/ml) but susceptible to imipenem (MIC= 0.25 µg/ml) and meropenem (MIC= 0.5 µg/ml). Carbapenemase production was demonstrated by modified Hodge test in all of the carbapenem-resistant isolates. In conclusion, ESBL-producing gram-negative isolates should be routinely tested with a screening method for carbapenemase activity and confirmation tests should be performed in suspected cases.
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Tuberculosis is still a major global health problem. Nowadays nucleic acid amplification tests which are recommended by the World Health Organization (WHO) become popular methods for the rapid detection of Mycobacterium tuberculosis complex (MTC). Recently introduced commercial Xpert MTB/RIF (Cepheid, USA) system is also a molecular method based on real-time polymerase chain reaction for simultaneous detection of both MTC and rifampicin resistance in the clinical sample. ⋯ No resistance were detected for the tested isolates. This study suggested that the sensitivity of Xpert MTB/RIF system in direct detection of M.tuberculosis in smear positive and smear negative samples was consistent with the reference methods. Moreover, the MTB/RIF test provided sensitive detection of tuberculosis in less than two hours.
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The majority of catheter-related bloodstream infections (CR-BSI) are associated with central venous catheters (CVCs) and most of them develop in patients staying at intensive care units (ICUs). The aim of this study was to assess the performance of different methods for the diagnosis of CR-BSI in neurology and neurosurgery ICUs of our hospital. This prospective study was carried out between January 2007 and January 2008 and all of the patients were followed daily for CR-BSI after the insertion of CVCs. ⋯ Sensitivity and NPV of the isolation method of the same microorganism from blood culture drawn through the catheter and drawn from the peripheral vein were 100%, specificity was 85% and PPV was 88% for the diagnosis of CR-BSI. Sensitivity, specificity, PPV and NPVs of Gram and drawn simultaneously from the peripheral vein and quantitative and semiquantitative cultures of the catheter tip in patients with removed catheter, were important factors in terms of diagnosis of CR-BSI. It was also concluded that AO staining could provide additional benefit in the diagnosis of CR-BSI since it has higher sensitivity, specificity, PPV and NPVs for peripheral blood cultures and catheter tip cultures compared to Gram staining.
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Toxigenic Clostridium difficile strains cause a spectrum of antibiotic-associated diseases ranging from self-limited diarrhea to severe life-threatening colitis. Pathogenesis primarily involves the action of two important cytotoxins, namely toxin A and toxin B. However, epidemics of C.difficile-associated disease due to the novel, highly virulent strains of C.difficile (binary toxin positive and toxin A variant) have been recognised in hospitals of some countries. ⋯ Our results have also indicated that 77.8% (28/36) of patients who harbored toxigenic C.difficile strains have the history of beta-lactam antibiotic (penicillin, cephalosporin and imipenem) use. It was thought that the data of this study would constitute a database on the toxin gene profiles of C.difficile in hospitalized patients with diarrhea both in our hospital and Turkey. The current data have indicated that for the time being there were no risk for isolates producing new toxin variants or binary toxin, however, continuous monitorization of such C.difficile strains is of crucial importance in order to detect the emergence of those strains and establish necessary control and preventive measures.
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Tularemia which is a zoonotic infection, caused by Francisella tularensis, has become a re-emerging disease in Turkey. Infection is often transmitted to human by handling animal tissues and products, but it is also possible to acquire the disease from contaminated water or food. Recently several cases and epidemics of tularemia have been reported in the northwest areas of Turkey, particularly in Marmara and West Black Sea regions. ⋯ All of the seropositive subjects were dealing with raising livestock and two were also farming. No history of contact with rat and wild animals or tick bite were detected, however it was noted that non-chlorinated fountain water has been used in both of these villages. In conclusion, our data emphasized that, populations inhabiting especially in rural area and dealing with farming and stock raising in our region are at risk for tularemia.