Ceftazidime-avibactam resistance determination in carbapenem-resistant Klebsiella pneumoniae infections before its use in practice.

INTRODUCTION: To ensure the appropriate usage of ceftazidime-avibactam (CAZ-AVI), recently introduced in our hospital, we aimed to determine susceptibility rates, enzyme analysis, and clonal relationship among strains, together with clinical data. METHODOLOGY: Between June 1 and September 30, 2021, demographic and microbiological data of the patients were recorded. In the obtained samples, meropenem and colistin minimal inhibitory concentration (MIC) levels, carbapenem resistance genes, and the clonal relationship were studied by molecular methods. CAZ-AVI was not used in any of the patients. RESULTS: 140 carbapenem-resistant Klebsiella pneumoniae were isolated from 57 patients. Resistance to CAZ-AVI was found in 76 (54.3%) strains. Out of 57 patients, 31 (54.4%) isolates could be reached. Meropenem MIC level was ≥ 32 µg/mL in 26 (83.9%), and colistin MIC level was ≥ 4 µg/mL in 17 (54.8%) isolates. Enzyme analysis revealed NDM in 20 (64.5%), OXA-48 in 17 (54.8%), and KPC in seven (22.6%). NDM + OXA-48 was determined in 10 (32.2%) strains. NDM was determined in all CAZ-AVI resistant strains, OXA-48 in 16.1% (2/5) strains. Seven genotypes were detected. The largest cluster was genotype 3 clusters (11 isolates). Of 31 patients, 22 (71.0%) died. CAZ-AVI was susceptible in one of the patients who survived and four who died. CONCLUSIONS: Before using a new antibiotic, each center should determine the basal data and phenotypic/genotypic resistance ratios specific to that antibiotic. While a high NDM rate and low CAZ-AVI sensitivity limit the use of the drug in our center, it is clear that CAZ-AVI use in sensitive strains will decrease mortality.

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.

High Carbohydrate, Fat, and Protein Diets Have a Critical Role in Folliculogenesis and Oocyte Development in Rats.

To date, there is no comparative data on the effects of carbohydrates, fat, and proteins, which are macronutrients, on female reproductive functions. Therefore, in this study, we investigated the effects of diets enriched with carbohydrates, fats, and proteins on folliculogenesis and oocyte development in female rats. 21-day-old rats that were just weaned were divided into 4 groups: control, carbohydrate, fat, and protein. The control group was fed with standard chow and the carbohydrate, fat, and protein groups were fed diets enriched with 75% carbohydrate, 60% fat, and 50% protein for 11 weeks, respectively. It was found that high-fat and high-protein diets caused an increase in the estrous cycle length compared to carbohydrate group (p < 0.05). Graafian follicle number decreased in the protein group compared to the control (p < 0.05). However, the atretic follicle number was higher in the fat group compared to the control group (p < 0.05). In the carbohydrate group, Zp1 was found to be lower than the control and protein groups, Zp2 was found to be lower than the control, and Zp3 was found to be lower than the fat group (p < 0.05). While BMP15 was similar between groups (p > 0.05), GDF9 was lower in all diet groups compared to the control (p < 0.05). Foxo3a was lower in the protein group compared to carbohydrate and control (p < 0.05). GAS2 was found to be higher in the control group than the fat group, and higher in the carbohydrate group than the fat and protein groups (p < 0.05). FSH, LH, Progesterone, and E2 levels were higher in all three diet groups than in the control (p < 0.05). Also, significant differences were observed between the groups regarding adiponectin, resistin, and leptin levels. Taken together, high carbohydrate, fat, and protein intake are associated with impairment of the menstrual cycle, depletion of the developing follicle types, and altered expression of folliculogenesis-specific genes and hormones. Therefore, long-term macronutrient diets may result in shortened reproductive periods and reduced fertilization potential in females in the long run.

Comparison of Six Aptamer-Aptamer Pairs on Rapid Detection of SARS-CoV-2 by Lateral Flow Assay.

BACKGROUND: SARS-CoV-2 is a threat to humanity. Both the spike (S) protein and its receptor binding domain (sRBD) are extensively used for rapid detection. Although real-time reverse transcription polymerase chain reaction (rRT-PCR) is mostly used method for the molecular detection of SARS-CoV-2, rapid assays for antigenic detection are always needed. Lateral flow assays (LFAs) are the most commonly used tests for this purpose, and aptamers having stability and long shelf life are used as capture reagents. OBJECTIVE: This study aimed to develop the LFAs based on the aptamer pairs for the antigenic detection of SARS-CoV-2 with the naked eye. METHOD: Gold nanoparticles (AuNPs) were used as labels, and six sandwich models by three different aptamers were prepared using 4 µM and 8 µM probes and two kinds of membranes for developing the LFAs. RESULTS: The 8 µM probe concentration and M2 membrane showed the best recognition of both the synthetic sRBD and SARS-CoV-2 coming from the naso/oropharingeal swabs by designed LFAs as 100% sensitivity and 93.3% specificity compared to the antibody-detecting LFAs. CONCLUSIONS: Our developed strip assays based on aptamer pairs recognized the target directly in 5-6 min with the naked eye. It was also concluded that aptamer pairs, membrane types, assay buffers, and probe concentrations have a significant role in the detection of SARS-CoV-2 by LFAs. HIGHLIGHTS: The detection of SARS-CoV-2 in clinical samples was demonstrated with the best aptamer pairs, sensitively and selectively among the designed six aptamer pairs for LFAs. Developed LFAs can be an alternative method to the conventional antibody-based LFAs for SARS-CoV-2 detection.

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.

Carbapenem-resistant Klebsiella pneumoniae outbreak with monoclonal spread: Evaluation of resistance genes and ceftazidime-avibactam susceptibility.

PURPOSE: The aim of this study was to investigate ceftazidime-avibactam (CAZ-AVI) susceptibility, carbapenemase genes, and clonal relationship in carbapenem-resistant Klebsiella pneumoniae (CrKp) isolates. METHODS: A total of 28 non-repetitive CrKp isolates with positive carbapenemase production determined by the modified carbapenem inactivation method (mCIM), were included in the study. Identification of the isolates was performed with MALDI-TOF MS (VITEK-MS, bioMerieux, France). The automated system (VITEK-2, bioMerieux) and gradient diffusion test (Etest, bioMerieux) were used to determine antibiotic susceptibility. The mCIM was performed according to CLSI (2021) recommendations. CAZ-AVI susceptibility was carried out using the standard disc diffusion method. Results were evaluated according to EUCAST 2022 criteria. The blaOXA-48, blaNDM, blaKPC, blaIMP and blaVIM genes were investigated by multiplex PCR. The clonal relationship between isolates was determined by both AP-PCR and PFGE methods. RESULTS: Of the total 28 isolates, 89.3% were susceptible to CAZ-AVI. blaOXA-48 gene was found in 85.7% of the isolates, blaOXA-48+blaNDM gene in 10.7%, and blaNDM gene in 3.6%. blaKPC, blaIMP and blaVIM genes were not detected. Three clusters with three different genotypes were determined by the PFGE method. The largest cluster was Genotype A (n:24), followed by Genotype B (n:3), and Genotype C (n:1). AP-PCR was highly compatible with PFGE. The isolates of Genotype A, mostly from the intensive care unit (ICU), were evaluated as outbreak strains with monoclonal dissemination. CONCLUSIONS: OXA-48 remains the most frequently detected enzyme in CrKp strains in our country. The ceftazidime-avibactam susceptibility rate of 89.3% indicates that this antibiotic is still effective against CrKp isolates. The unnoticed outbreak detected in our study revealed the severity of intra-hospital cross-contamination affecting different wards, including the ICU. Therefore, in order to limit the spread of CrKp isolates, it is of great importance to implement strict infection control measures, and molecular surveillance programs, especially in the ICU.

Cessation of Rectal Screening for Vancomycin-Resistant Enterococci: Experience from a Tertiary Care Hospital from Türkiye.

OBJECTIVE: Here, we compared the impact of different polices on the epidemiology of Vancomycin-resistant Enterococcus faecium bloodstream infections (VRE-BSIs) in a tertiary care hospital including two hospital buildings (oncology and adult hospitals) in the same campus. MATERIAL AND METHODS: All patients who were hospitalized in high-risk units were screened weekly for VRE colonization via rectal swab between January 2006 and January 2013. After January 2013, VRE screening was only performed in cases of suspicion of VRE outbreak and during point prevalence studies to evaluate the epidemiology of VRE colonization. Contact precautions were in place for all VRE-positive patients. The incidence density rates of hospital-acquired (HA)-VRE-BSIs were compared between two periods. RESULTS: While the rate of VRE colonization was higher in the second period (5% vs. 9.5% (p < 0.01) for the adult hospital, and 6.4% vs. 12% (p = 0.02 for the oncology hospital), there was no increase in the incidence rate HA-VRE BSIs after the cessation of routine rectal screening in either of the hospitals. CONCLUSION: Screening policies should be dynamic and individualized according to the epidemiology of VRE as well as the workforce and cost. Periodical rectal screening of VRE can be discontinued if suspicion of an outbreak can be carefully monitored.

Designing of rapid assay for the detection of RdRp/Orf1ab specific to SARS-CoV-2.

SARS-CoV-2 is still threat and mostly used detection method is real time reverse transcriptase polymerase chain reaction (rRT-PCR) for the open reading frame (Orf1ab), RNA-dependent RNA polymerase (RdRp), nucleocapsid (N) and envelope (E) genes of virus. However, rRT-PCR may have false negative rate for the nucleic acid detection. Since the RdRp/Orf1ab has high sensitivity for the molecular detection, two sandwich models, Model 1A-Model 1B, based on hybridization on lateral flow assay (LFA) were designed here and applied with the synthetic and clinical samples of RdRp/Orf1ab. In this purpose colloidal gold nanoparticles (AuNPs) were used as label. Membranes having different flow rate, three oligonucleotide probe concentrations and running buffers were used. Although synthetic target sequence was recognized by all the LFAs, PCR products obtained from either the synthetic plasmid DNA or oro/nasopharyngeal swabs were detected by Model 1 A using W12 membrane. Designed strip assays detected the RdRp/Orf1ab of the clinical samples as 100% sensitivity and specifity. It means that they might be used for the detection of virus and can be modified for the recognition of mutant genes of virus. These findings also demonstrated the importance of membranes, sandwich models, probe concentrations and sample contents for developing LFAs for viral detection.

Investigation for the presence of bacteria and antimicrobial resistance genes in sea snails (Rapana venosa).

INTRODUCTION AND OBJECTIVE: The aims of this study were to search for the presence of bacteria in sea snails (Rapana venosa) by using culturomics and Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and the antibiotic resistance/susceptibility of the sea snails. MATERIAL AND METHODS: The anti-microbial susceptibilities of Gram-negative bacteriawas assessed by the Kirby-Bauer disk diffusion method, the presence of the mcr genes (mcr-1 to -5), the major carbapenemase and ß-lactamase resistant genes in Gram-negative bacteria, using mPCR method and 16S rRNA sequence analysis of A. hydrophila isolates. RESULTS: Bacterial growth accounted for 100% and 94.2% in the samples of intestine and meat, respectively, in the snails. The main organisms identified by MALDI-TOF MS were A. salmonicida subsp. salmonicida at 33.7%, followed by Raoultella ornithinolytica at 9.6% (10/104) and Staphylococcus warneri at 7.7% in meat and intestine samples. Aeromonas hydrophila/punctata (caviae), Aeromonas sobria, Klebsiella aerogenes, Klebsiella oxytoca, Raoultella planticola, Shewanella putrefaciens and Vibrio vulnificus are intrinsic or chromosomally-mediated resistant against ampicillin. No mcr genes (mcr-1 to -5), the major carbapenemase and ß-lactamase resistant genes were found. Aeromonas salmonicida subsp. salmonicida showed very low levofloxacin and meropenem resistance levels at 2.9%. When the sequence was searched in the Blast database, the genome of A. hydrophila/punctata (caviae) isolate showed high similarity with the A. hydrophila sequences. CONCLUSIONS: Conclusions. The findings obtained not only provide data about the proportion of bacteria in the gut and meat of the sea snails and their antibiotic resistance/susceptibility, but also show the absence of carbapenemase, colistin, and ß-lactamase resistant genes among bacterial isolates from sea snail gut microbes.

Comparative humoral response of mRNA and inactivated vaccines against COVID-19 in healthy adults aged 60 years and older.

INTRODUCTION: A vaccine against coronavirus disease 2019 (COVID-19) is critically needed for older adults because of the increased morbidity and mortality rates. METHODOLOGY: In this prospective study, we analysed the titre magnitude of the IgG antibodies directed against the SARS-CoV-2 Spike Protein S1 (S1-RBD) antigen in both CoronaVac and Pfizer-BioNTech groups. The samples were tested to detect antibodies that bind to the receptor-binding domain of the spike protein of SARS-CoV-2 using the Enzyme-Linked Immunosorbent Assay (ELISA) technique with SARS-CoV-2 IgG II Quant. The cut-off value was > 50 AU/mL. GraphPad Prism software was used. Statistical significance was defined at p < 0.05. RESULTS: The CoronaVac group (12 females, 13 males) had a mean age of 69.64 ± 1.38 years. The Pfizer-BioNTech group (13 males, 12 females) had a mean age of 72.36 ± 1.44 years. The anti- S1-RBD titre decrease rate from the 1st to the 3rd month for CoronaVac and Pfizer-BioNTech groups was 74.31% and 86.48%, respectively. There was no statistically significant difference in the antibody titre between the 1st month and 3rd month for the CoronaVac group. However, there was a significant difference between the 1st and 3rd month in the Pfizer-BioNTech group. In addition, there was no statistically significant difference in the genders between the 1st and 3rd month of the antibody titres for both the CoronaVac Pfizer-BioNTech group. CONCLUSIONS: The levels of anti-S1-RBD, the preliminary outcome data of our study, represents one piece of the puzzle of humoral response and duration of vaccination protection.

Does marking as sterile mean really sterile? Stenotrophomonas maltophilia outbreak caused by a blood-gas injector containing liquid heparin.

An outbreak investigation was initiated after detecting an increase in the number of patients with Stenotrophomonas maltophilia bloodstream infections (SM-BSIs) througout the hospital. S. maltophilia was isolated from the cultures of blood-gas injectors containing liquid heparin. The incidence density of SM-BSIs decreased significantly after prohibiting the use of those injectors.

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.

A long-lasting Sphingomonas paucimobilis outbreak: A potential for pathogens to persist on environmental devices despite disinfection measures.

BACKGROUND: Sphingomonas paucimobilis, an aerobic, non-fermentative, Gram-negative opportunistic bacillus, can colonize everywhere in hospital settings where water is used. We reported a hospital S paucimobilis outbreak that persisted for nearly 2 years despite all necessary preventive measures. METHODS: Over a period from February 13, 2020 to December 3, 2021, 67 patients were identified to have S paucimobilis as documented by positive cultures from clinical samples, along with 19 positive environmental samples. RESULTS: Bacterial regrowth for molecular analysis could be obtained in 49 isolates (39 clinical, 4 extracorporeal membrane oxygenation (ECMO) water heater devices, 1 unused mouthwash solution, 5 water samples from thoracic drainage aspirators). Two distinct clonally indistinguishable genotypes were detected in AP-PCR and PFGE analyses, with 100% consistency. The main cluster was obtained consistently throughout the outbreak from 30 samples (61.2%: 24 clinical, 4 ECMO, 1 unused mouthwash solution, 1 water sample from the thoracic drainage aspirator). The other cluster involved 15 clinical samples and 4 water samples from the thoracic drainage aspirators. CONCLUSIONS: Given that waterborne pathogens can spread to a wide range of equipment used in healthcare environments, the pathogens can persist on the surfaces of environmental devices even after recommended disinfection measures have been applied. Therefore, individual tracking of all devices used in critical care settings, such as thoracic drainage aspirators and ECMO water heater devices, with records of pre- and post-disinfection procedures is of paramount importance for complete elimination of the source of infection.

Stenotrophomonas maltophilia outbreak with a commercial blood gas injector as the culprit and interventions for source and prevention: A possible passage between patient and ECMO water heater device.

BACKGROUND: Despite low virulence of Stenotrophomonas maltophilia, it represents one of the leading drug-resistant bacteria. We report a large outbreak of S. maltophilia infection associated with an unexpected source, which turned out to be a commercial needleless blood gas injector. METHODS: Over a period from January 1 to December10, 2021, 113 patients were identified to have S. maltophilia infection as documented by positive cultures from the clinical samples, extracorporeal membrane oxygenation (ECMO) water heater devices and commercial needleless blood gas injectors. RESULTS: Sixty-seven isolates (59 clinical, 4 ECMO, 4 blood gas injectors) were sent for molecular analysis. Both arbitrarily primed polymerase chain reaction and pulsed-field gel electrophoresis analyses showed 12 distinct genotypes. Of 67 isolates, 58 were clonally related (86.6%), with 52 indistinguishable strains from 4 blood gas needleless injectors, 46 patients' samples (78%), and 2 ECMO samples (50%). Two ECMO samples and 1 clinical sample were clonally identical. CONCLUSIONS: In the event that eradication of infections would not be possible despite taking all environmental disinfection measures including the ECMO devices, unexpected sources, such as a commercial needleless blood gas injector, should not be omitted from the list for surveillance. In addition, obtaining surveillance cultures of ECMO water reservoirs should be placed in the routine clinical practice.

Moelerella wisconsensis: first isolation from lungs and spleen of a horse infected with Streptococcus dysgalactia subsp. equisimilis.

Moellerella wisconsensis is a Gram-negative, facultative anaerobic bacillus of Entero-bacteriaceae family, and it is an uncommon pathogen in domestic animals. To date, five cases were reported including two dogs, two cattle, and a goat. Streptococcus equisimilis is the second common bacterial agent after the S. equi subsp. zooepidemicus in equine pneumonia cases. The present report describes the isolation of M. wisconses from lungs and spleen of a 10-year-old Arabian horse (May 08, 2022) at post-mortem examination being co-infected with S. equisimilis. Clinical and pathological findings included bilateral nasal discharge, conjunctivitis, sternal recumbency, severe diffuse necrosuppurative rhinitis, multi-focal fibrinopurulent pneumonia and purulent lymphadenitis. Polymerase chain reaction assays showed no viral nucleic acids of equid alphaherpesvirus (EHV) 1, EHV-4, equine arteritis virus and equine papilloma virus. The antibiogram test revealed that the isolate was sensitive to several antibiotics except colistin. Taken together, the present report documents the first isolation of M. wisconsensis from lungs and spleen of a horse; hence, experimental studies are needed to clarify the pathogenity and pathogenesis of M. wisconsensis.

[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.

Diagnostic and treatment outcomes of patients with pulmonary tuberculosis in the first year of COVID-19 pandemic.

Background: The COVID-19 pandemic has put a significant strain on human life and health care systems, however, little is known about its impact on tuberculosis (TB) patients. Aims: To assess the impact of COVID-19 pandemic on pulmonary tuberculosis (PTB) diagnosis, treatment and patient outcomes, using the WHO definitions. Methods: A cross-sectional study was conducted in Malatya region, Turkey (population 800 000). Data on regional PTB test numbers, case notification rates and PTB patients' clinical characteristics and treatment outcomes were collected. Data from the first pandemic year (2020) were compared to data from the previous 3 years (2017-2019). The attitudes and experiences of patients were analysed. Results: Despite a non-significant 22% decrease in annual PTB case notifications (P = 0.317), the number of TB tests performed (P = 0.001) and PTB patients evaluated (P = 0.001) decreased significantly during the pandemic year compared with the previous 3 years. The proportion of patients with high (3/4+) sputum acid-fast bacilli grades (P = 0.001), TB relapse (P = 0.022) and treatment failure (P = 0.018) increased significantly. The median 64.5-day treatment delay detected in 2017-2019 increased significantly to 113.5 days in 2020 (P = 0.001), due primarily to patients' reluctance to visit a health care facility. Conclusion: In addition to the problems with case detection, this study shows notable deterioration in several indicators related to the severity, contagiousness and poor outcomes of TB, which had already been suppressed for decades.

The impact of COVID-19 pandemic on nosocomial multidrug-resistant bacterial bloodstream infections and antibiotic consumption in a tertiary care hospital.

We investigated the change in the epidemiology of nosocomial bloodstream infections (BSIs) caused by multidrug-resistant bacteria during Coronavirus Disease (COVID-19) and antibiotic consumption rates at a pandemic hospital and at the Oncology Hospital which operated as COVID-19-free on the same university campus. Significant increases in the infection density rate (IDRs) of BSIs caused by carbapenem-resistant Acinetobacter baumannii (CRAB) and ampicillin-resistant Enterococcus faecium (ARE) were detected at the pandemic hospital, whereas carbapenem-resistant Klebsiella pneumoniae BSIs were increased at the non-pandemic Oncology Hospital. Pulsed field gel electrophoresis showed a polyclonal outbreak of CRAB in COVID-19 intensive care units. Antibiotic consumption rates were increased for almost all antibiotics, and was most significant for meropenem at both of the hospitals. Increased IDRs of CRAB and ARE BSIs as well as an increased consumption rate of broad-spectrum antibiotics emphasize the importance of a multimodal infection prevention strategy combined with an active antibiotic stewardship program.