Antimicrobial susceptibility profile of ceftolozane/tazobactam, ceftazidime/avibactam and cefiderocol against carbapenem-resistant Pseudomonas aeruginosa clinical isolates from Türkiye.

PURPOSE: Carbapenem resistant Pseudomonas aeruginosa (CR-PA) is escalating worldwide and leaves clinicians few therapeutic options in recent years, ß-lactam/ß-lactamase inhibitor combinations (ceftolozane-tazobactam, ceftazidime-avibactam) and a new siderophore cephalosporin (cefiderocol) have been approved for the treatment of P. aeruginosa infection and have shown potent activity against isolates defined as carbapenem resistant. The aim of this study was to determine the phenotypic profile of these agents against CR-PA in the emerging setting of carbapenemases. METHODS: CR-PA clinical isolates were collected from three teaching hospitals in different geographical regions between January 2017-December 2021. All isolates were subjected to phenotypic carbapenemase testing using modified carbapenem inactivation method. MICs were determined by reference broth microdilution and evaluated according to EUCAST standards, while genotypic profiling was determined using PCR methods. RESULTS: 244 CR-PA sourced most frequently from the respiratory tract (32.2%), blood (20.4%) and urine (17.5%) were evaluated. Of all isolates, 32 (13.1%) were phenotypically and 38 (15.6%) were genotypically defined as carbapenemase-positive. The most common carbapenemase was GES (63.1%), followed by VIM (15.8%). The MIC50/90(S%) of ceftazidime/avibactam, ceftolozane/tazobactam and cefiderocol in all CR-PA isolates were 4 and 32 (80%), 1 and > 64 (69%) and 0.25 and 1 mg/L (96%), respectively. Cefiderocol was also the most active agent in carbapenemase-positive isolates (90%). CONSLUSION: While ceftolozane/tazobactam and ceftazidime/avibactam remained highly active against CR-PA devoid of carbapenemases, cefiderocol provided potent in vitro activity irrespective of carbapenemase production. When considering the potential clinical utility of newer agents against CR-PA, regional variations in carbapenemase prevalence must be considered.

Molecular characterization and antibiotic resistance of clinical Bacteroides and related genera from a tertiary care center in Türkiye.

OBJECTIVES: This study was conducted to measure the prevalence of antibiotic resistance, and corresponding resistance genes among Bacteroides and related genera in a tertiary hospital. METHODS: We examined 138 clinical strains of Bacteroides, Phocaeicola and Parabacteroides species isolated between July 2018 and June 2022. Antibiotic susceptibility tests were conducted using agar dilution. The bft gene and antibiotic resistance genes were targeted by real-time PCR. RESULTS: Resistance rates of all strains against ampicillin, cefoxitin, piperacillin-tazobactam, meropenem, imipenem, clindamycin, metronidazole, and tigecycline were 97.8 %, 28.3 %, 11.6 %, 7.9 %, 5.1 %, 47.8 %, 0 % and 4.3 %, respectively. Non-fragilis Bacteroidales spp. (NFB) exhibited lower susceptibility rates compared to B. fragilis for cefoxitin, clindamycin, and piperacillin-tazobactam. The prevalence of meropenem resistance was higher in B. fragilis (15.5 %) than in NFB (0 %). Among all strains, the rates of cepA, cfxA, cfiA, ermF, ermG, ermB, nim, linA, mefA, msrSA, tetQ, tetX, tetX1 and bft genes were 42.8 %, 44.9 %, 8.7 %, 44.2 %, 10.9 %, 2.2 %, 0.7 %, 29.0 %, 17.4 %, 7.2 %, 76.1 %, 8.0 %, 37.7 % and 16.7 %, respectively. In five B. fragilis strains, insertion sequences [IS1187(n = 3), ISBf6(n = 1), IS612B(n = 1)] were detected in the upstream region of cfiA. NimE with ISBf6 on plasmid pBFM29b was detected in one B. fragilis strain, intermediate to metronidazole (MIC = 16 µg/mL). ErmF was the most abundant gene responsible for clindamycin resistance. TetQ and tetX1 genes exhibited a higher frequency in strains that were not susceptible to tigecycline (MIC ≥8 µg/ml). CONCLUSIONS: Monitoring the resistance trends of Bacteroides and related genera is crucial given the observed resistance to all classes of antibiotics and the presence of various resistance mechanisms.

Determination of safety status and probiotic properties of Enterococcus strains isolated from traditional cheeses in Turkey.

AIMS: This study aimed to evaluate the probiotic properties of Enterococcus strains isolated from Turkish traditional cheeses. METHODS AND RESULTS: Fifty-two Enterococcus spp. were taxonomically determined as follows: Enterococcus faecium (26), Enterococcus faecalis (18), Enterococcus durans (6), and Enterococcus italicus (2). The ability of isolates/strains to survive the harsh conditions (acidity and in-vitro gastric solution) of the gastrointestinal tract was established. They also showed auto-aggregation, hydrophobicity, and co-aggregation ability. Hydrophobicities of the strains were found between 0.8%-21%, 0.7%-56%, and 2%-63% for xylene, chloroform, and ethyl acetate, respectively. Autoaggregation values of the Enterococcus strains were 4%-20%, 7%-30%, and 36%-98% after 2, 4, and 24-h incubation, respectively. In this study, the Enterococcus strains tested showed co-aggregation ability with the Escherichia coli ATCC 25922, Salmonella Typhimurium ATCC 14028, and Staphylococcus aureus ATCC 25923. The results of PCR amplification revealed that only five strains possess virulence factor genes (gelE,asa1,cyl A,esp). We determined antibiotic resistance, biofilm forming abilities, and hemolytic activity for safety evaluation of strains. CONCLUSIONS: In this large and comprehensive study, we found that only few of Enterococcus strains have promising probiotic potential, among which E. faecalis ES1 and E. faecium EM1 showed the best probiotic properties (are the most promising probiotic candidates).

[The Importance of Gram-stained Smears in the Diagnosis of Nocardia Infections]. / Nocardia Enfeksiyonlarinin Tanisinda Gram Boyanmis Yaymalarin Önemi.

Nocardia species are low virulence bacteria found in nature. They can be an infectious agent, especially in patients with risk factors such as underlying immunosuppression, chronic lung disease, and malignancy. They can be easily overlooked because they are not seen frequently and has no pathognomonic symptoms. With this study, it was aimed to draw attention to the importance of microscopic examination of Gram-stained smears in the diagnosis of Nocardia infections in routine microbiology laboratories. Cases in which Nocardia spp. were detected in their clinical samples between November 2014-December 2015 in Hacettepe University Medical Faculty Hospital were included in the study. In the direct microscopic examination of Gram-stained smears of the samples arriving to the laboratory, the incubation periods of the cultures of the samples compatible with Nocardia spp. were extended. Then relevant colonies were identified by conventional microbiological methods and also by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS, bioMerieux, France) automated system. Species-level identification of Nocardia isolates was performed by 16S rRNA gene sequence analysis. To demonstrate the genetic relationship between Nocardia isolates, pulsed-field gel electrophoresis (PFGE) was performed. In vitro susceptibility of the isolates against amoxicillin-clavulanate (AMC), linezolid, moxifloxacin, trimethoprim-sulfamethoxazole (TMP-SXT), amikacin, imipenem, clarithromycin, cefepime, cefotaxime, ceftriaxone, and ciprofloxacin was determined using the gradient strip method (E-test). A total of 19 Nocardia spp. strains were isolated from eight patients. Four cases exhibited repeated growth of Nocardia spp. up to a period of nine months. The most frequently isolated species was N.cyriacigeorgica, which was identified in four cases. Other species isolated from patients were N.asteroides, N.transvalensis, N.farcinicia, and N.asiatica/arthritidis. When the results obtained with DNA sequence analysis and MALDI-TOF MS were compared, 16 (84.2%) of 19 isolates were correctly identified to the genus level and 9 (47.4%) to the species level with MALDI-TOF MS, while three (15.8%) isolates could not be identified, and seven (36.8%) isolates were misidentified. According to the PFGE results, it was determined that the strains isolated from the same patient were genetically identical. All isolates were susceptible to amikacin, cefepime, cefotaxime, ceftriaxone, imipenem, linezolid, and except one isolate to TMP-SXT. Among the study isolates, the most common resistance was against ciprofloxacin (62.5%), followed by clarithromycin (37.5%). N.cyriacigeorgica was determined as the most frequently detected and the most resistant species to antibiotics in the study population. Direct microscopic examination of clinical specimens is one of the most valuable methods for the identification of Nocardia-type bacteria, which is difficult to isolate in microbiology laboratories. With this study, the importance of examining Gram-stained clinical samples was emphasized in the identification of Nocardia species, which can emerge with a wide variety of clinical forms and can be easily overlooked. In addition, antibiotic susceptibility profiles of the isolated bacteria were determinedto contribute to species-specific susceptibility profiles. Accurate identification of Nocardia species will contribute to clinical and epidemiological studies.

An Outbreak of Vancomycin-Resistant Enterococci in a City Hospital Intensive Care Unit: Molecular Characterization of Resistance.

Background and Objectives: Vancomisin-resistant Enterococci (VRE), is a resistant microorganism that colonizes and causes infections in hospitalized patients. The aim of this study was to show the spread of vancomycin-resistant Enterococcus faecium (VREfm) step-by-step in all intensive care units, which started with the growth of VREfm on 2 December 2021 in the blood culture of a patient hospitalized in the anesthesia intensive care unit of our hospital and was found to have reached epidemic size in the surveys. Materials and Methods: Rectal swab samples were taken from all patients hospitalized in intensive care units, VRE colonization was determined, the VanA and VanB resistance genes associated with the vancomycin resistance of VREfm isolates were determined by PCR method, and clonal association analysis was performed by Arbitrarily Primed-PCR (AP-PCR) and PFGE (pulsed-field gel electrophoresis). Results: In our study, VRE were detected in 61 of 2601 rectal swab samples. In total, fifty-four (85.52%) of the VRE isolates were Enterococcus faecium, three (4.91%) was Enterococcus faecalis, three (4.91%) was Enterococcus gallinorum, and one (1.63%) was Enterococcus casseliflavus. It was determined that all of the 54 VREfm isolates, which were the most detected among all VRE isolates, carried the vanA gene. In the clonal association analysis of the isolates by AP-PCR and PFGE methods, it was found that they had 12 different genotypes, 48 of them were included in any cluster, the clustering rate was 88.8%, and the largest cluster was the genotype 1 cluster, with 36 isolates. Of the 54 patients with VREfm isolated recently, 18.51 percent of the clinical samples were isolated before the survey, and 9.25% were isolated after the survey. It was determined that 100% of VREfm isolates were resistant to ampicillin, levofloxacin, ciprofloxacin, high-level gentamicin, trimethoprimsulfamethoxazole, and teicoplanin, 7.4% to tigecycline, and 1.85% to linezolid. Conclusions: In our study, in the clonal association analysis performed by isolating VREfm in rectal swab samples, it was found that 88.8% of the samples were indistinguishably similar, and that the increase in the number of VREfm infections after the index case in our hospital was associated with the epidemic. VREfm infections cause long-term hospitalization, costs and also deaths, which shows the seriousness of the event, and the importance of the combination of epidemiological and molecular analysis in epidemic research.

Molecular Epidemiological Analysis of Bacillus Pseudo-Outbreak due to Contaminated Culture Tubes Containing Stuart Medium.

BACKGROUND: It is challenging to determine whether Bacillus species other than Bacillus anthracis cause infections. Pseudo and true outbreaks of Bacillus spp. have been noted. Here, we present a molecular analysis of a Bacillus spp. pseudo-outbreak caused by contaminated culture tubes containing Stuart medium. METHODS: Between January and March 2015, a high percentage of Bacillus spp. was isolated from the wound samples of inpatients at the Karabuk University Hospital, and an outbreak was suspected. Environmental and staff nasal samples were cultured aerobically, and Bacillus spp. were isolated from some of them. However, the isolation of Bacillus spp. in throat cultures of outpatients suggested contamination caused by culture tubes containing Stuart medium. We examined two lots of culture tubes used in the hospital. Although the culture tubes' expiry date and storage conditions were suitable, Bacillus spp. grew in one of these lots. A total of 47 Bacillus spp. isolated during this period were identified, and the clonal relationship among the isolates was investigated by arbitrarily primed polymerase chain reaction. RESULTS: Twenty-seven strains were identified as Bacillus megaterium and 20 as Bacillus firmus. Of the four strains isolated from the Stuart medium, two were identified as B. firmus and the other two were B. megaterium. Two B. firmus strains isolated from the Stuart medium and two B. firmus strains obtained from the coronary intensive care environmental samples were matched and clustered within the same genotype. We recalled all culture tubes containing Stuart medium. After another brand's culture tubes were distributed, no growth was observed. It was then understood that the pseudo-outbreak source was contaminated culture tubes containing Stuart medium. CONCLUSIONS: Microbiological controls of medical materials and equipment should be regularly checked to prevent outbreaks (true or pseudo).

[Investigation of the VISA and hVISA Presence in Methicillin-Resistant Staphylococcus aureus Isolates by Various Methods]. / Metisiline Dirençli Staphylococcus aureus Izolatlarinda Çesitli Yöntemlerle VISA ve hVISA Varliginin Arastirilmasi.

Staphylococcus aureus is an important human pathogen that causes community and hospital-acquired infections. The role of vancomycin in the treatment of methicillin-resistant S.aureus infections is indisputable. However, vancomycin intermediate susceptible S.aureus (VISA) and heterogeneously VISA (hVISA) isolates, that cause treatment failures during the use of vancomycin, cannot be detected by routine laboratory methods. The gold standard method for the detection of these isolates is the population profile analysis-area under the curve (PAP-AUC) method. In this study, it was aimed to determine the presence of mecA and mecC gene regions that cause methicillin resistance, the clonal relationship between isolates, and the presence of VISA and hVISA. A total 68 methicillin-resistant S.aureus (MRSA) strains were included in this study which were isolated in the microbiology laboratory of the hospital between 2015- 2020. Identification of the isolates were determined by matrix assisted laser desorption ionization-time of flight mass spectrophotometry (VITEK MS, BioMérieux, France). Methicillin resistance was investigated by disk diffusion method using cefoxitin (30 µg, Bioanalyse, Türkiye) disk and vancomycin MIC values were determined by broth microdilution method. mecA and mecC gene regions were investigated by polymerase chain reaction (PCR) method. The presence of VISA and hVISA were investigated by modified agar screening, macro gradient diffusion test and confirmated by PAP-AUC methods, and the clonal relationship between isolates were investigated by pulsed field gel electrophoresis method. The mecA gene region was determined in all isolates, but the mecC gene region was not found in any of the isolates. The MIC50 value of the isolates was determined as 1 µg/mL and the MIC90 value was determined as 2 µg/mL by broth microdilution method. Six VISA and four hVISA suspected strains were detected by a modified agar screening method. Among the isolates identified as suspicious by the modified agar screening method, one isolate was evaluated as VISA and one isolate was evaluated as hVISA by the gold standard PAP-AUC method. No dominant epidemic isolate has been identified by PFGE. As a result, VISA and hVISA were determined in the hospital. The increase in these isolates is a serious concern. For this reason, it is believed that it would be beneficial to investigate the VISA/hVISA ratios in MRSA isolates at certain periods, and to take necessary infection control measures to implement measures and practices to prevent the spread of these isolates in the community and hospital environment.

[Clinical Properties of COVID-19 Developed in the Patients with Tuberculosis]. / Tüberküloz Hastalarinda Gelisen COVID-19'un Klinik Özellikleri.

There are limited publications about the Coronavirus disease 19 (COVID-19) clinic developing in the patients with active tuberculosis (TB). In this study, it was aimed to determine some clinical features of patients diagnosed with TB who also had COVID-19. In this retrospective cross-sectional study, 71 patients with COVID-19 were evaluated out of a total of 595 patients diagnosed with TB in our province between 2015 and 2021. After contracting COVID-19, a total of nine (12.6%) TB patients were hospitalized, five (7%) patients were admitted to the intensive care unit, three (4.2%) were intubated, and one (1.4%) died due to severe COVID-19. The frequency of such health problems was found to be higher than the normal population living in the same province. None of these complications were observed in a total of 40 female TB patients, and the hospital and intensive care unit admission rates for men were significantly higher than for women. The results of this study showed that men with active TB had more health problems due to COVID-19 than the normal population. Comprehensive studies are needed to detail the resilience of female TB patients against COVID-19.

[A Case of Intra-abdominal Tuberculosis Due to Mycobacterium bovis Mimicking Ovarian Cancer: Importance of Microbiological Diagnosis]. / Over Kanserini Taklit Eden Mycobacterium bovis Kaynakli Intra-abdominal Tüberküloz Olgusu: Mikrobiyolojik Taninin Önemi.

Mycobacterium bovis causes gastrointestinal tuberculosis by being transmitted through consumption of infected milk and dairy products, mostly in developing countries, and can spread to the other neighbourhood intra-abdominal tissues and organs. In addition to the symptoms such as weight loss, weakness, abdominal pain, and chronic diarrhea in female patients with abdominal tuberculosis, findings such as pelvic mass, ascites and CA-125 elevation may be encountered. Patients with these symptoms usually preliminary diagnosed as having ovarian cancer. It is very important to distinguish between these two diseases quickly, which have different treatment protocols. In this case report, a case of intra-abdominal tuberculosis caused by M.bovis, whose diagnosis was confirmed by microbiological methods with the findings mimicking ovarian cancer such as weight loss, ascites, pelvic mass and increased CA-125 was presented. Tuberculosis was considered in the differential diagnosis of a 23-yearold female patient with abdominal pain, weight loss, ascites, pelvic mass, and elevated CA-125 (643.9 U/ml) findings and a mass in the left tubaovarian region on abdominal CT. The ileum biopsy sample taken during colonoscopy and ascitic fluid sample taken with paracentesis were sent to our laboratory for acid-fast bacilli (AFB) staining and tuberculosis culture. In our laboratory, samples were incubated in both liquid culture system [BACTEC MGIT 320 Mycobacteria Culture System (Becton Dickinson,USA)] and solid culture medium [Lowenstein-Jensen Medium (Becton Dickinson,USA)] and AFB smears were performed. While AFB smears were negative, ileum biopsy material showed growth on day 14 and ascitic fluid sample on day 11 in liquid culture medium. AFB smear was prepared from broth and red bacilli were seen on a blue background that formed cord factor. The bacillus was identified as Mycobacterium tuberculosis complex by the immunochromatographic rapid test [BD MGIT TBc Identification Test (BD,USA)]. The anti-tuberculosis drug treatment was initiated with the diagnosis of intra-abdominal tuberculosis. The isolated bacillus was found to be sensitive to isoniazid, rifampicin, ethambutol and resistant to streptomycin, according the drug susceptibility test results. Subspecies identification of M.tuberculosis complex was investigated by matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) but could not be determined by this method. Genotyping was performed with the GenoType MTBC VER 1.X (Hain Lifescience, HardwiesenstraBe, Germany) kit. The isolate was identified as M.bovis. In the follow-up of the patient three months later, it was determined that tumor markers, ascitic fluid and intra-abdominal lymph nodes regressed significantly and the mass in the left ovary completely disappeared. In this report, we presented a case with intra-abdominal tuberculosis whose clinical, radiological and laboratory findings mimic ovarian cancer to imply the importance of microbiological diagnosis.

An evaluation of patients with a previous endemic coronavirus infection during the COVID-19 pandemic.

Few studies exist on the clinical manifestation of coronavirus disease 2019 (COVID-19) in patients who previously had a common cold due to an endemic coronavirus (eCoV). In a retrospective scan of the data obtained in our microbiology laboratory, 64 patients who were diagnosed with an eCoV infection between 2016 and 2020 were identified. National COVID-19 surveillance data showed that four (6.2%) of 64 patients were infected with severe acute respiratory syndrome coronavirus 2 by the end of 2020, while, simultaneously, the COVID-19 prevalence in the city of Malatya ranged from 7.8% (polymerase chain reaction-based diagnosis) to 9.2% (total diagnosis). The differences were found statistically significant (6.2% vs. 7.8%, p < .01; 6.2% vs. 9.2%, p < .001). Patient interviews and evaluation of medical records revealed that these four patients did not manifest any severe COVID-19 symptoms despite their substantial comorbidities, and they did not require hospitalization. Consequently, despite a low number of samples, we determined a lower frequency of COVID-19 among the patients who had a prior eCoV infection, and the results of this study support the previous findings that people with a prior eCoV infection develop a milder case of COVID-19. Our results may provide some insights for future studies aiming at vaccine development, but detailed investigations are still required.

Short-term experiences of a liver transplant centre before and after the COVID-19 pandemic.

BACKGROUND/AIM: With the COVID-19 pandemic, managing the process of solid organ transplantation has become a significant matter for transplant centres. In this study, we report our experiences on evaluating the effects of COVID-19 in patients with recent liver transplants. MATERIALS AND METHODS: We evaluated patients who received liver transplants during three close consecutive periods of time. For transplants conducted between October 1 and December 31, 2019, January 1 and March 10, 2020 and March 11 and June 22, 2020, the lung tomographies of patients were inspected for radiological signs of viral pneumonia. For patients after March 11, 2020, the hospital's electronic database system was scanned for preoperative and postoperative SARS-CoV-2 testing from Real-time Polymerase Chain Reaction (RT-PCR) of the respiratory tract samples. RESULTS: A total of 149 patients over the age of 18 who received liver transplants at our centre between October 1, 2019 and June 22, 2020 were evaluated. During this time span, our centre conducted liver transplants on patients from 34 different provinces and also abroad. Within this time period, a total of nine patients had respiratory samples with a positive SARS-CoV-2 RT-PCR test. PCR of respiratory tract samples was performed in 21 (14%) patients to identify the other potential infective agents in the respiratory tracts; Rhinovirus and Influenza A were detected in two and respiratory syncytial virus (RSV) was detected in one patient. During the transplant periods, 99 (67.1%) patients were evaluated with computed tomography (CT). The CT findings of 18 (12%) patients were consistent with viral pneumonia. There was a statistically significant difference between the groups only in terms of air bronchogram findings (P = .012). CONCLUSION: The clinical status of our short-term liver transplant patients was far better than we originally anticipated, but it remains obvious that the necessary precautions should continue to be taken.

[The Microbiological Analysis of a Rhizobium radiobacter Outbreak After Intravitreal Injection]. / Intravitreal Enjeksiyon Sonrasi Ortaya Çikan Rhizobium radiobacter Salgininin Mikrobiyolojik Analizi.

Rhizobium radiobacter, which is found in nature and causes tumorigenic plant diseases can lead to opportunistic infections, especially in people with underlying diseases. In our study, endophthalmitis that observed in ten patients caused by R.radiobacter bacteria after intravitreal ranibizumab injection in Ophthalmology Clinic were examined microbiologically. Vitreous fluid samples of 13 patients who received intravitreal ranibizumab injection were sent to the Microbiology Laboratory from Van Yuzuncu Yil University Faculty of Medicine's Ophthalmology Clinic for microbiological examination in December 21, 2016. Samples were examined under microscope after staining with Gram and cultured with 5% sheep blood agar and Eosin Methylene Blue (EMB) agar. The culture plates were incubated for 18-24 hours at 37°C in 5% CO2. At the end of this period, catalase, oxidase, and urease tests were performed on the colonies. The identification and antibiotic susceptibility tests of microorganisms growing in vitreous fluid samples were performed using BD Phoenix (Becton Dickinson, USA), Vitek 2 Compact (BioMerieux, France), and Vitek MS (BioMerieux, France) systems. In addition, 16S rDNA sequence analysis was performed and the pulsed field gel electrophoresis (PFGE) method was used to determine the clonal relationship between the isolates. After growing in cultures (one day after the procedure), culture samples were collected from the objects, medical tools and equipment, hands of healthcare staff and a new injection solution in the area where the procedure was performed. R.radiobacter was isolated in 10 of the vitreous fluid samples of 13 patients, and no bacterial growth was detected in 3. The microorganisms were found to be gram-negative bacilli, non-fermenter, motile, catalase/oxidase/urease positive, in compliance with R.radiobacter. All isolates were identified as R.radiobacter by BD Phoenix (Becton Dickinson, USA), Vitek 2 Compact (BioMerieux, France), and Vitek MS (BioMerieux, France) (database v2.0) systems. R.radiobacter isolates were found to be resistant to ampicillin, amoxicillin/clavulanate, trimethoprim/ sulfamethoxazole, cefotaxime and ceftazidime; susceptible to cefuroxime, cefepime, amikacin, gentamicin, imipenem, meropenem, ciprofloxacin, levofloxacin and piperacillin/tazobactam. The isolates were identified as R.radiobacter by 16S rDNA sequence analysis. PFGE showed that all isolates had the same band profile. R.radiobacter isolates with the same band profile likely revealed that the contamination was from the same source. However, the growth of R.radiobacter was not detected in the cultures made from the objects, medical instruments and supplies, the hands of healthcare professionals and the new injection solution in the area where the procedure was performed, and the source of the agent could not be determined. The results have shown that intravitreal injection procedure carries a risk for R.radiobacter infection. Disinfection and antisepsis conditions, before and during the procedure, is important for the prevention of such infections. This study is the first epidemic outbreak report of endophthalmitis caused by the same strain of R.radiobacter and the second article in which R.radiobacter was reported as the cause of endophthalmitis after intravitreal injection.

[Employee Safety and Biosafety Applications in Microbiology Laboratories; A Multicenter Evaluation in Turkey]. / Mikrobiyoloji Laboratuvarlarinda Çalisan Güvenligi ve Biyogüvenlik Uygulamalari Açisindan Türkiye'de Çok Merkezli Bir Degerlendirme.

Medical laboratory personnel may be exposed to various hazards, especially biological and chemical, during their routine activities. In this multicenter study, which could reflect the nation wide results, it was aimed to determine the safety and biosecurity practices of the employee working in medical microbiology laboratories and to reveal the current situation. A total of 1072 personnel working in the Medical Microbiology Laboratory of 23 hospitals (14 medical faculty hospitals, seven ministry of health training and research hospitals and two state hospitals) from different provinces were provided with a questionnaire consisting of 33 questions inquiring about the rules, opinions, attitudes and behaviors regarding safety and biosafety practices. Statistical analyses were made with institutions, age groups, gender, educational background, working time and occupational groups in terms of exposure to biological and chemical hazards. It was determined that approximately 50% personnel of the university/ training and research hospitals and 2/3 of the state hospitals personnel consumed food and beverages in the laboratories (p<0.05). Compared with other hospitals, it was determined that in state hospitals; the absence of separate resting room (35%), the personnel finding their own knowledge and practices inadequate (28.9%), laboratory coats washed at home (95%), educational organization and participation rates (90%) and medical waste information levels of the personnel were higher (p< 0.05). It was determined that as the age progresses, the rate of education, food and beverage consumption in the laboratory, not being outside the laboratory with protective equipment (gloves, masks and laboratory coats) and the history of laboratory acquired infections were increased (p< 0.05). It was observed that washing the laboratory coats at home was higher in the younger age group and hospital washing was higher in the elderly group (p< 0.05). There was no significant difference between the genders in terms of food and beverage consumption in the laboratory (p= 0.09). It was determined that periodic health checks were not performed in 1/3 of both sexes, but the use of gloves and compliance with medical waste rules was lower in men. Female employees find themselves inefficient in terms of knowledge and practices (p< 0.05). The rate of those who did not have their periodic checkups at regular intervals was higher in the high school and master of science education groups; While non-compliance with medical waste rules, food and beverage consumption in the laboratory was highest in the primary and high school graduates, the lowest rates were found in the master and doctorate groups (p< 0.05). The rate of those who had regular health checkups was higher in the group of specialist physicians and technicians (p< 0.05). It was observed that the rule of not going out of the laboratory with protective equipment was fully observed in the 35+ years working group, while compliance was 70-85% in other groups (p< 0.05), hepatitis B vaccination rate was highest in specialist doctors and lowest in cleaning and other personnel group (p< 0.05). Highest non-compliance rate with medical waste rules was observed in the cleaning personnel group (p< 0.05). As a result, although advances have been made in employee safety practices in medical microbiology laboratories in our country in recent years, it has been found that it is not yet sufficient. The results indirectly reflected the profile of medical laboratories in our country. In the laboratories, physical space and equipment deficiencies should be eliminated, periodic health checkups and vaccination should be provided, non-staff entrance to the laboratory and food, beverage and cigarette consumption should be prevented, laboratory coats should be washed in the hospital, in-service trainings, including medical waste training, should be conducted and these trainings should be developed through mechanisms that will change the behavior.

HEV seroprevalence in blood donors in Turkey by two commercial total anti-HEV Ab ELISA kits.

Previous hepatitis E virus (HEV) seroprevalence studies in Turkey have shown high variabilities, leading to conflicting results. We aimed to re-evaluate HEV seroprevalence among blood donors in Turkey using the Wantai (Beijing, China) and the Dia.Pro (Milan, Italy) total anti-HEV antibody (Ab) enzyme-linked immunosorbent assay (ELISA) kits and compare their performances and to investigate the presence of HEV RNA in blood donors. Serum total anti-HEV antibodies were determined in a total of 2011 volunteer blood donor samples collected from different regions of Turkey (807 from Ankara, 243 from Kayseri, 284 from Izmir, 200 from Malatya, 200 from Kahramanmaras, and 277 from Van). HEV RNA was evaluated by a real-time polymerase chain reaction in a total of 272 anti-HEV seropositive samples. The country-wide HEV seroprevalence was calculated as 11.5% (Dia.Pro) and 12.2% (Wantai) with seropositivity rates of 12.0%-12.5% in Ankara, 7.4%-8.2% in Kayseri, 14.5%-15.5% in Malatya, 8.1%-8.8% in Izmir, 15.0%-16.0% in Kahramanmaras, and 12.6%-13.4% in Van by Dia.Pro and Wantai kits, respectively. The lowest detectable Ab concentrations were 0.16 and 0.14 units/mL WHO, for the Dia.Pro and the Wantai assays, respectively, showing no significant difference between assays. HEV RNA was not detected in any of the anti-HEV seropositive samples. Compared with previous studies, HEV was shown to have a higher overall seroprevalence in Turkey. Despite its limitation, the current study represents the most comprehensive HEV seroprevalence study in Turkey performed with two different commercial ELISA assays with high sensitivities so far. Further investigation is required to determine HEV genotypes in Turkey.

Case report: systemic tuberculosis caused by Mycobacterium bovis in a cat.

BACKGROUND: The diagnosis of previous cases of feline tuberculosis in Turkey has been made based solely on pathological changes without isolation of the causative agent. This case report details the first case of feline tuberculosis in Turkey for which the causative agent (Mycobacterium bovis) was confirmed with microbiological isolation, morphological evaluation, molecular (PCR) characterization and antibiotic sensitivity. CASE PRESENTATION: Systemic tuberculosis was diagnosed via postmortem examination of a 5-year-old stray male cat. Mycobacterium bovis was isolated from the lungs, bronchial and gastrointestinal lymph nodes, kidney and liver. The isolate was defined as M. bovis using the Genotype MTBC assay (Hain Lifescience, Germany), which allows differentiation of species within the Mycobacterium tuberculosis complex with an easy-to-perform reverse hybridization assay. Pathological changes were characterized by multifocal to coalescing granulomatous inflammation in the lungs, liver, lymph nodes and kidneys. Further pathological changes included severe, diffuse, hepatocytic atrophy, periportal fibrosis with lymphohistiocytic infiltration, multifocal lymphohistiocytic interstitial nephritis, mild focal pulmonary anthracosis and mild renal and hepatic amyloidosis. Infection by immunosuppressive viral pathogens including feline herpes virus-1, feline immunodeficiency virus and feline parvovirus virus were ruled out by polymerase chain reaction assay (PCR). The isolated mycobacteria were susceptible to isoniazid, ethambutol, rifampicin or streptomycin. CONCLUSION: Disseminated M. bovis is a rare infection in cats. Involvement of submandibular lymph nodes suggested that primary transmission might have been the oral route in the present case.

[Performance of MALDI-TOF MS for the identification of gram-negative bacteria grown on eosin methylene blue (EMB) agar: A simple method for improving the effectiveness of identification]. / MALDI-TOF MS'nin EMB agarda üreyen gram-negatif bakterileri tanimlama performansi: Tani etkinligini arttiran basit bir yöntem.

Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) is a new method that is increasingly used in microbiology laboratories due to its ability of reliable and rapid identification (ID) of bacteria and fungi. However, some problems emerge in the routine clinical diagnosis since only one gram-negative selective medium has been suggested up to date. Though EMB agar is one of the traditional gram-negative selective media, there is no data in the scientific literature, about the ID performance of MALDI TOF MS with the gram-negative bacteria grown on this medium. In this study, we tested the ID performance of MALDI-TOF MS for gram-negative isolates on EMB agar and aimed to develop a rapid and easy sample preparation method for improving this performance. A total of 468 clinical isolates of gram-negative bacteria, consisting of 37 different species from 20 genera, were included in this study. The isolates were identified using the Vitek MS MALDI-TOF MS (Bio Mérieux, France) both directly from EMB agar, and also through a two-step colony washing (once with physiologic saline, and three times with 70% ethanol) method. The performances of these two IDs were compared. In the direct reading from EMB medium, 382 (81.6%) of 468 studied isolates were correctly identified at species level; no ID was detected for 80 (17%) isolates, and 6 (1.2%) isolates (four at the genus level) were misidentified Performance of MALDI-TOF MS directly from EMB agar was excellent (100%) for 14 species including Stenotrophomonas maltophilia, Klebsiella oxytoca, Salmonella spp., and Proteus mirabilis; and lowest for Providencia spp. (62.5%), Escherichia coli (70.5%) and Acinetobacter spp. (70.7%). Following the washing procedure which was performed about 20 min with simple laboratory equipment, 434 (92.7%) isolates were correctly identified at species level; 30 (6.4%) strains could not be identified, and four (0.85%) isolates (two at the genus level) were misidentified. Statistical analyses indicated that the washing procedure defined here significantly increased the overall ID performance of MALDI-TOF MS with EMB agar (p= 0.001), particularly with improving the IDs of those markedly dye-absorbing genera, such as E.coli and A.baumannii. In this study, EMB agar which has no data until today on its suitability for mass spectrometric identification has been shown to be useful for bacterial identification with MALDI-TOF MS. In addition, the unidentified gram-negative bacteria in the direct reading from the EMB medium have been shown to be identified after the colony washing method as described here. Determination of the different medium alternatives will contribute to effective usage of MALDI-TOF MS in microbiology laboratories.

[Investigation of blaOXA-48-like genes in carbapenemase producing Klebsiella spp. isolates]. / Karbapenemaz üreten Klebsiella pneumoniae suslarinda blaoxa-48-benzeri genlerin arastirilmasi.

The emergence and spread of multi-drug-resistant (MDR), extended-spectrum beta-lactamase (ESBL) producing carbapenem-resistant members of Enterobacteriaceae family has become a worldwide health problem. Carbapenem resistance caused by blaKPC, blaNDM gene regions are sporadic and blaOXA-48 gene region is endemic in our country. The aim of this study was to determine the presence of blaOXA-232, blaOXA-181, blaOXA-162, blaOXA-204, blaOXA-244, blaOXA-163, blaOXA-245 genes in OXA-48 like carbapenemase producing Klebsiella pneumoniae isolates. The isolates used in this study were provided from the Medical Microbiology Laboratory collection of Sakarya University Sakarya Training and Research Hospital. Identification and antibiotic susceptibility tests were determined by the VITEK 2® automated system (biomerieux, France) and the carbapenemase production of isolates was determined by the modified Hodge test. Minimal inhibitor concentration (MIC) values were determined with broth microdilution method. The isolates containing the blaOXA-48-like gene region were identified by real-time polymerase chain reaction (Rt-PCR) method using consensus primers. In "High Resolution Melting Analysis (HRMA)" method carried out by using "Type-it HRM PCR" (Qiagen, Hilden, Germany) kit, isolates which showed a deviation in melting temperatures (Tm) were selected with the suspicion of OXA-48 variant. The sequence analysis (ABI 3500, Applied Biosystems, USA) was carried out to determine which variants were present in these isolates. Compatibility of MIC values was determined between VITEK 2® and the microdilution method with the rate of 82% for imipenem, 77% for meropenem and 90% for ertapenem in carbapenemase-producing K.pneumoniae isolates. In 45 of 100 K.pneumoniae isolates, the blaOXA-48-like gene region was found to be positive by the Rt-PCR method. For the determination of OXA-48 variants, these 45 isolates were evaluated by HRMA method. The sequence analysis revealed that 41 (91.2%) isolates contained blaOXA-48/blaOXA-245 gene regions, while 2 (4.4%) isolates were found to contain blaOXA-181 gene regions and 2 (4.4%) isolates were found to contain blaOXA-244 gene regions. This is the first study to determine OXA-48 and OXA-244 positivity in blaOXA-48-like gene regions in Turkey. As a result of this study, the OXA-48-like gene region was found to be 45%, of which 4.4% had blaOXA-181 and 4.4% had blaOXA-244 gene regions. The detection of blaOXA-48-like gene regions will guide for the selection of antibiotics in critical patient groups.

[Investigation of high-risk ST131 clone in ESBL-producing Escherichia coli isolates isolated from urine and non-urinary clinical specimens with MALDI-TOF MS and real time PCR]. / Idrar ve idrar disi klinik örneklerden izole edilen GSBL üreten Escherichia coli izolatlarinda yüksek riskli ST131 klonunun MALDI-TOF MS ve gerçek zamanli PCR ile arastirilmasi.

In recent years, the ST131 clone was identified as a high risk pandemic clone among Escherichia coli isolates by multilocus sequence typing (MLST) studies and has been associated with extended spectrum beta-lactamase (ESBL) production (often with CTX-M-15) and antibiotic resistance especially against fluoroquinolones. The aim of this study was to determine the rate of high risk ST131 clone in ESBL producing E.coli isolates in our region, to investigate the sensitivity of MALDI-TOF MS in the detection of ST131 clone, and to compare the frequency of antimicrobial resistance among ST131 and non-ST131 isolates. A total of 251 urinary and 50 non-urinary E.coli isolates identified in our hospital central laboratory between February 2016-February 2017 were included in the study. Real-time PCR and MALDI-TOF MS methods were used for the detection of E.coli ST131 clone. For the statistical evaluation of the rate of antibiotic resistance among isolates of ST131 and non-ST131 clones, chi-square test was used. p value under 0.05 was considered as significant. Of the 301 isolates, 110 (36.6%) and 92 (30.6%) isolates were identified as ST131 clone by real-time PCR and MALDI-TOF MS, respectively. According to real-time PCR results, 91 (36.3%) of 251 urinary isolates and 19 (38%) of 50 non-urinary isolates were found as ST131 clone; there was no statistically significant difference between the groups. Ciprofloxacin resistance was found to be significantly higher in ST131 isolates than the non-ST131 isolates (78.2%, n= 86 vs. 53.4%, n= 102). No statistically significant difference was determined for the other antibiotics tested. For the detection of E.coli ST131 clone; sensitivity of MALDI-TOF MS was 84%, specificity was 100% while positive predictive value was 100% and negative predictive value was 92%. In conclusion, further investigation of the high risk E.coli ST131 clone in our country, in which ESBL ratios and antibiotic resistance rates, especially in fluoroquinolones, are high, is important for the development of new strategies to control antibiotic resistance. MALDI-TOF MS method is particularly useful for easy and fast detection of the high risk E.coli ST131 clone.

[Co-production of OXA-48 and NDM-1 Carbapenemases in Providencia rettgeri: the first report]. / Providencia rettgeri'de OXA-48 ve NDM-1 karbapenemaz genlerinin birlikte üretimi: ilk bildirim.

Our country is the epicenter of the OXA-48-like carbapenemase-producing Klebsiella and Escherichia coli; and in the recent years, the concern has been increasing due to both spreading of this resistance to other members of Enterobacteriaceae family and acquiring other carbapenemases by the OXA-48-producing strains. In this study, OXA-48 and NDM-1 co-production was presented in Providencia rettgeri. Two P.rettgeri strains that were resistant to all antimicrobials except colistin and tigecyclin, were isolated from two patients in the burn unit of our hospital, including one from the urine sample of a 68 years female in April 2017, and the other from a burn wound swab of a 35 years old male, in November 2017. Minimal inhibitory concentrations (MICs) of the isolates for imipenem and meropenem were measured as ≥ 32 µg/ml; and for colistin and tigecyclin were 1 ve 0.5 µg/ml, respectively. Multiplex PCR analysis showed that both strains were carrying blaOXA-48 and blaNDM-1 carbapenemases, and blaTEM extended spectrum beta-lactamase genes. By using DNA sequence analysis, the TEM gene was typed as blaTEM-1. The Pulsed Field Gel Electrophoresis (PFGE) analysis indicated that these two strains which were consecutively isolated from two different patients in a single unit within about seven months were genetically indistinguishable. No significant data that could explain the spread of these isolates was obtained from our retrospective analysis of the medical records including the results of environmental surveillance cultures, and patients' history. Nevertheless, hospital infection control committee enforced the infection control measures in that unit, and no further isolation was observed within three months period following the last isolation, neither from environmental nor from clinical samples. With this study, it was emphasized that the co-production of OXA-48 and NDM-1 carbapenemases which was reported from only three Enterobacteriaceae species up to date was ongoing for spreading to other species by using horizontal route, and also showing a potential to be a growing problem in the hospitals, by clonal expansion (vertical route). Effectively using of the molecular epidemiological methods will provide useful data to better understand the transmission dynamics of such rare, but problematic species in hospitals.

High Genetic Diversity among Stenotrophomonas maltophilia Isolates from Single Hospital: Nosocomial Outbreaks or Genotypic Profile Changes during Subcultures.

BACKGROUND: Stenotrophomonas maltophilia is a non-fermentative gram-negative bacillus which is widely recognised as an important nosocomial pathogen causing pneumonia, blood-stream, wound and urinary tract infections, particularly in immunosuppressed patients. The aim of this study was to evaluate a nosocomial outbreak of by S. maltophilia in an intensive care unit of a tertiary hospital and evaluate unexpected multiclonality. METHODS: A total of 11 isolates from respiratory cultures in intensive care unit of a 24 bed tertiary hospital obtained over a one months period and one isolate obtained from the nebuliser during environmental screening were investigated. The bacteria were identified by Phoenix 100 system. The clonal relatedness was evaluated by PFGE and semi-automated repetitive sequence-based PCR. Genotyping tests were repeated for 10 serial subcultures. RESULTS: PFGE and DiversiLab yielded 10 genotypic profiles for 12 isolates. Four to eight different genotypes were observed from 10 subcultures of the same isolate. CONCLUSION: We conclude that, high genetic diversity and supposed multiclonal appearance of the outbreak isolates may be due to changing profiles during subcultures most probably depending on hypermutation.