Flow Cytometry as a Rapid and Valuable Method in Investigation of Colistin Resistance in Carbapenem-Resistant Klebsiella pneumoniae Isolates.

Rapid detection of antimicrobial resistance is crucial for early initiation of appropriate therapy. The aim of this study was to investigate whether resistance to colistin, the last-resort antibiotic, in carbapenem-resistant Klebsiella pneumoniae (CRKP) isolates can be detected accurately and rapidly by flow cytometry (FCM). The VITEK 2 automated system was used to identify 85 K. pneumoniae strains and to determine their resistance to carbapenems. The minimum inhibitory concentration (MIC) values for colistin in 85 CRKP strains were determined by broth microdilution (BMD), which is the reference method. In addition, FCM was used, combined with DiBAC4(3) fluorescent stain, to determine colistin susceptibility. The MIC50 value of the strains, 80% of which were resistant to colistin by the BMD method, was 16 mg/L, and the MIC90 value was 32 mg/L. When FCM was compared with the reference method, it was determined that the specificity was 94.1%, sensitivity was 100% of FCM, and Cohen's kappa value was 0.96. Colistin susceptibility results with FCM were obtained within an average of 2 h. These findings suggest that FCM holds great promise as a rapid and reliable alternative method for detecting colistin resistance in CRKP strains.

Emerging importance of multidrug-resistant Stenotrophomonas maltophilia infections in neonatal intensive care unit in a tertiary center in Turkey.

OBJECTIVE: Stenotrophomonas maltophilia is an emerging multi-drug resistant, opportunistic pathogen in the neonatal intensive care unit (NICU). In this study, we aimed to assess the incidence, clinical features, antibiotic susceptibility, and treatment options of S. maltophilia infection among the healthcare-associated infections (HAIs) in the neonatal unit. METHODS: In this study, the patients who were hospitalized in the NICU between January 2020 and December 2021 with S. maltophilia isolated from clinical samples were included. Demographic, clinic features, and microbiological findings of the patients were retrospectively evaluated by using the medical records. The samples (lower respiratory tract, urine, peritoneal fluid) were first examined microscopically by gram preparation and cultured. Antibiotic susceptibility tests were performed according to the recommendations of The European Committee on Antimicrobial Susceptibility Testing (EUCAST) for TMP-SMX. RESULTS: S. maltophilia was isolated in 38 clinical samples of the 20 patients who were hospitalized at the NICU between January 2020 and December 2021. A total of 40 % (n = 8) of samples from different patients were accepted as colonization. Ventilator-associated pneumonia was determined in 55 % (n = 11), and urinary tract infection in 5 % (n = 1). S. maltophilia-associated bacteremia was not detected in any of the cases. The TMP-SMX susceptibilities of the strains were as it follows: 3 (15 %) were resistant (R), 7 (28 %) were susceptible (S), and 10 (47 %) were susceptible-increased exposure (I). Three of these patients were given dual antibiotics therapy (levofloxacin plus TMP-SMX) and nine of them were given only TMP-SMX. The most common hospital-acquired infectious agents are Gram negative microorganisms (51 %), followed by coagulase negative staphylococci (CNS), Staphylococcus aureus (24 %) and S. maltophilia (24 %). CONCLUSION: Increasing TMP-SMX resistance and specific drug and dosage-related problems in the neonatal unit are important problems in treatment management.

Recurrent Campylobacter jejuni Enteritis in a Patient with Common Variable Immunodeficiency Over an Eight Year Period.

BACKGROUND: In this case, we report multiple isolations of C. jejuni in a patient with common variable immunodeficiency between 2010 and 2018. METHODS: C. jejuni was investigated in the stool samples of the patient by classical culture method using selective media under microaerophilic atmosphere. Antibiotic susceptibilities of the strains were determined by disk diffusion method. RESULTS: Eight C. jejuni strains were isolated from the patient. All strains were resistant to ciprofloxacin. An erythromycin susceptible isolate was replaced by a resistant strain within a one- and four-month period. An erythromycin resistant isolate was replaced by a susceptible one within a year. The patient recovered all episodes by intravenous immunoglobulin replacement and antibiotherapy. CONCLUSIONS: Prolonged or recurrent C. jejuni infections should not be overlooked in immunosuppressed patients. The fact that antibiotic susceptibility may change should also be kept in mind.

Investigating the Significance of Non-jejuni/coli Campylobacter Strains in Patients with Diarrhea.

Campylobacter is one of the most commonly reported foodborne bacteria worldwide. Although Campylobacter jejuni and Campylobacter coli have been reported to be responsible for the great majority of campylobacteriosis, the burden of infections by species other than C. jejuni and C. coli have been increasing as a result of a transition to diagnostic test methods that enable the isolation of emerging species. The aim of the present study was to recover C. jejuni, C. coli, and emerging species from the stool samples of 500 patients with gastroenteritis and 100 healthy subjects via the use of a filtration method and culture techniques using Butzler agar and mCCDA under a microaerobic or hydrogen-enriched atmosphere, identify the species by multiplex PCR methods and assess the significance of emerging species in enteric diseases. Thirty-one (6.2%) Campylobacter spp. were isolated from the stool samples of diarrheic patients but none from healthy individuals. Of 31 isolates, 21 (67.8%), nine (29%), and one (3.2%) were identified as C. jejuni, C. coli, and Campylobacter concisus by multiplex PCR, respectively. The filtration method was superior to the culture technique using mCCDA under a microaerobic atmosphere. C. concisus was evaluated as the etiology of gastroenteritis as a result of laboratory and clinical evaluations. The present study was the first to indicate that emerging Campylobacter species are rarely detected and C. concisus is linked to acute gastroenteritis in Turkey where additional studies are warranted to clarify the significance of emerging species in gastroenteritis.

Evaluation of Blood Cultures from SARS-CoV-2-Positive and Negative Adult Patients.

Bacteremia and fungemia are significant causes of morbidity and mortality that frequently occur as co-infections with viral respiratory infections, including SARS-CoV-2. The aim of this study was to evaluate the microorganisms that were isolated from the blood cultures of SARS-CoV-2-positive and negative patients and investigate their antimicrobial resistance patterns. A retrospective analysis was performed of 22,944 blood cultures sent to the laboratory between November 2020 and December 2021. Blood culture analyses were performed using the BD Bactec FX automated system. Identification was carried out using conventional methods, namely, VITEK-2 and MALDI-TOF MS. Antibacterial/antifungal susceptibility tests were performed according to EUCAST/CLSI recommendations. SARS-CoV-2 tests were performed with RT-PCR. Culture positivity was detected in 1630 samples from 652 patients. Of these 652 patients, 633 were tested for SARS-CoV-2; 118 (18.6%) were positive and 515 (81.3%) were negative. The bacteria and fungi that were isolated at the highest rate in SARS-CoV-2-positive patients were methicillin-resistant coagulase-negative staphylococci (MR-CoNS) (21.5%), Escherichia coli (12.4%), Klebsiella pneumoniae (12.4%), Candida albicans (1.65%), and Candida glabrata complex (1.65%), while in the negative patients, the highest rates were for E. coli (21.3%), MR-CoNS (13.5%), K. pneumoniae (12.05%), C. albicans (2.1%), Candida parapsilosis (1.1%), and Candida tropicalis (0.9%). No statistically significant difference was determined between COVID-19-positive and negative patients in terms of detection, such as with the Pseudomonas spp., Enterococcus spp., and methicillin-resistant Staphylococcus aureus isolated from the blood cultures (p > 0.05). The most common isolate was MR-CoNS in SARS-CoV-2-positive patients (p = 0.028). Acinetobacter baumannii was more frequent (p = 0.004) and carbapenem-resistant K. pneumoniae was isolated at a higher rate (60% vs. 43%) in SARS-CoV-2-positive patients compared to SARS-CoV-2-negative patients (p > 0.05). These findings highlight the fact that isolation procedures should not be disregarded and the distribution of bacterial/fungal agents of bloodstream infections and their antibiotic resistance should be followed up during a pandemic, such as in the case of COVID-19.

Prevalence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium among Patients with Urogenital Symptoms in Istanbul.

Chlamydia trachomatis, Neisseria gonorrhoeae, and Mycoplasma genitalium are the three most commonly reported sexually transmitted bacteria. The present study aimed to investigate the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium in urogenital samples collected from 18-68-year-old Turkish patients who were admitted to the hospital with various urogenital symptoms. A total of 360 patients with symptoms of STD were included in the study. Following DNA extraction by QIAamp Mini Kit, the presence of C. trachomatis, N. gonorrhoeae, and M. genitalium were investigated using multiplex real-time PCR. Causative organisms were identified in 68 (18.9%) of 360 patients. C. trachomatis, N. gonorrhoeae, and M. genitalium were detected in 40 (11.1%), 14 (3.9%), and 28 (7.8%) of the patients, respectively. Patients 21-30 years of age represented more than one-third (37.8%) of positive patients. Of all patients, dual infections of C. trachomatis-M. genitalium, N. gonorrhoeae-C. trachomatis, N. gonorrhoeae-M. genitalium, and triple infection of C. trachomatis-N. gonorrhoeae-M. genitalium were determined in 1.6% (6/360), 1.3% (5/360), 0.2% (1/360), and 0.2% (1/360) of the patients, respectively. In CT-, NG-, and MG-positive patients, different STI agents were also found such as HIV, HBV, HPV, HSV2, T. pallidum, and T. vaginalis. In conclusion, among C. trachomatis, N. gonorrhoeae, and M. genitalium, CT was the most frequently detected bacterial cause of STDs in our hospital at Istanbul. Co-infections, which comprise more than one-fifth of the cases, should not be underestimated. Regular screening and following up of STD agents using multiplex real-time PCR-based diagnostic methods enabling the immediate detection of co-infections are essential for the treatment and primary prevention of STDs.

[Determining the Prevalence of Norovirus Infection in Diarrheal Patients and Evaluation of Different Diagnostic Methods]. / Ishalli Hastalarda Norovirüs Sikliginin ve Farkli Tani Yöntemlerinin Duyarliliklarinin Belirlenmesi.

Norovirus is one of the viruses that cause gastroenteritis in humans, characterized by symptoms of vomiting and diarrhea. The prevalence of norovirus, known as the leading cause of epidemic gastroenteritis, is remarkable in sporadic cases. Easy-to-apply diagnostic methods based on antigen detection such as enzyme immunoassay (EIA) and immunochromatography (ICG) used to diagnose norovirus infections generally have high specificity rates but lower sensitivity rates that can change according to the conditions. In this study it was aimed to determine the prevalence of norovirus and other gastroenteritis causative viruses in diarrheal patients and determine the sensitivity and specificity rates of EIA and ICG methods in sporadic cases by the chosen gold standard molecular reference method real-time reverse transcriptase polymerase chain reaction (rRT-PCR). In this study, 184 stool samples that met the study criteria and sent to Istanbul University Istanbul Faculty of Medicine Medical Microbiology Laboratory for routine bacteriological culture between January-July 2018 were included. All samples were evaluated with diagnostic kits BD MAX Enteric Viral Panel (Becton Dickinson, Canada) for rRT-PCR, RIDASCREEN Norovirus 3rd Generation (C1401) (R-Biopharm, Germany) for EIA, RIDAQUICK Norovirus Test (N1402) (R-Biopharm, Germany) for ICG, according to the manufacturer instructions. In terms of the presence of norovirus in 184 stool samples, 7 (3.8%) positive results were obtained by EIA method, 8 (4.3%) by ICG method, and 14 (7.6%) by rRT-PCR method. By accepting the rRT-PCR as a reference method, the sensitivity and specificity of the EIA method were determined as 50% and 100% and of the ICG method as 57% and 100%, respectively. The numbers and percentages of positivity for rotavirus, sapovirus, astrovirus and adenovirus, including coinfections were 30 (16.3%), 5 (2.7%), 2 (1%), 1 (0.5%), respectively. In this study, it was determined that norovirus, alone or together with other viral agents is frequently detected in patients with diarrhea and there was no difference in the frequency between age groups and genders. This causative agent which is not routinely investigated in our country should be considered when evaluating patients with diarrhea and/or vomiting. It seems that EIA and ICG methods are easy to apply, have high specificity but have limited sensitivity in sporadic cases in the diagnosis of norovirus. It is thought that the detection of the true frequency of norovirus and high sensitivity rates can only be achieved by preferring rRT-PCR in the diagnosis. It would be useful for the laboratories to choose the method to be used in the diagnosis of norovirus according to the characteristics of the cases and diagnostic methods.

[First Case of COVID-19 Positive Candida auris Fungemia in Turkey]. / Türkiye'de Ilk COVID-19 Pozitif Candida auris Fungemi Olgusu.

Candida auris is a species of fungus that has gained importance in recent years owing to its ability to cause hospital infections and epidemics, resistant to antifungal agents and disinfection processes and frequently misidentified by commercial systems. Hospital outbreaks caused by C.auris have been reported from some countries. It has been determined that C.auris has lower virulence than Candida albicans; however, it is associated with high mortality rates in immunocompromised individuals. An increase in the incidence of invasive fungal infections which can lead to serious complications and death, has been identified in severe coronavirus-2019 (COVID-19) patients or immunocompromised individuals with underlying disease. Studies demonstrated an increase in the frequency of C.auris isolation in COVID-19 patients with candidemia. In this report, the first case of COVID-19 positive C.auris fungemia detected in Turkey was presented. A 71-year-old male patient with a history of myocardial infarction, diabetes mellitus, donation of a single kidney and lobectomy surgery due to lung cancer was hospitalized in the pandemic thoracic surgery service due to the findings consistent with viral pneumonia on thoracic computed tomography. Favipiravir 2 x 600 mg and intravenous dexamethasone 1 x 6 mg therapy was administered. The patient tested positive for SARS-CoV-2 polymerase chain reaction, and severe involvement of the left lung was detected in the following days. Antibiotics were administered, followed by insertion of a right jugular vein catheter and initation of tocilizumab. The patient was transferred to the intensive care unit due to increased respiratory distress. Yeast growth was detected in the patient's hemoculture. The yeast strain could not be identified using API ID 32C (bioMerieux, France) (Sacchromyces kluyveri, Candida sake, unacceptable profile), but was identified as C.auris using the VITEK MALDI TOF MS (bioMerieux, France) (99.9%) system and confirmed by sequencing. The minimum inhibitor concentration values were detected as 3 µg/ml for amphotericin B; > 256 µg/ml for fluconazole; 0.19 µg/ml for voriconazole; 0.19 µg/ml for itraconazole; 0.016 µg/ml for posaconazole; 1 µg/ml for caspofungin and 0.094 µg/ml for anidulafungin by using the antibiotic gradient method. The patient's initial treatment comprised meropenem 3 x 1 g, vancomycin 2 x 1 g, caspofungin 1 x 70 mg, and continued as caspofungine 1 x 50 mg after the loading dose, and vancomycin 1 x 1 g/48 hours from the third day of treatment. The patient died on the ninth day after developing candidemia. The present case is the first case of fungemia caused by C.auris in a COVID-19 positive patient in Turkey, and it emphasizes the need of caution for fungemia due to C.auris in intensive care units in our country which has a high COVID-19 incidence.

Molecular Typing of Campylobacter jejuni and Campylobacter coli of Human Strains Isolated in Turkey Over an Eight-Year Period.

BACKGROUND: Campylobacter spp. is one of the leading causes of bacterial foodborne infections worldwide. In this study, we aimed to investigate the genetic diversity of 341 Campylobacter strains isolated in Turkey. METHODS: Campylobacter spp. was identified by phenotypical methods and PCR. Species level identification was carried out by the hippurate hydrolysis test and PCR. C. jejuni and C. coli strains were typed by using flaA-RFLP and PFGE. RESULTS: Of 341 strains, 300 (88%), 37 (10.8%), and four were identified as C. jejuni, C. coli, and non-jejuni/non-coli, respectively. The hippurate hydrolysis test misidentified 12% of 341 strains. The typeabilities of flaA-RFLP and PFGE were 100% for C. coli, whereas those of flaA-RFLP and PFGE for C. jejuni were 99.3% and 99%, respectively. The discriminatory power of the combination of PFGE and flaA-RFLP was determined to be higher than either method alone for both C. jejuni and C. coli. Both of the strains were so diverse that 80% and 64% of C. jejuni and C. coli genotypes included only one strain, respectively. In two patients, Campylobacter strains that were isolated from the first stool samples were C. jejuni where as those isolated from the second samples, collected eight and 20 days after the collection of the first samples, were C. coli. C. jejuni strains that were recovered from two different stool samples of two patients, collected 1 - 2 days apart, were found to be genetically different. CONCLUSIONS: Species identification of Campylobacter strains should be done using molecular methods. Combination of two methods is prerequisite for increasing the accuracy of molecular typing. Mixed or subsequent infection by different Campylobacter species and C. jejuni of different genotypes should not be underestimated.

Molecular and phenotypical investigation of ciprofloxacin resistance among Campylobacter jejuni strains of human origin: high prevalence of resistance in Turkey.

Campylobacteriosis is one of the most frequently reported zoonoses worldwide. The well-documented increase in the ciprofloxacin resistance has increased the importance of rapid detection of the resistance. The incidence of ciprofloxacin resistance was investigated using real-time PCR. Identification of one hundred and fifty-eight strains was performed by PCR. Minimum inhibitory concentration (MIC) of ciprofloxacin was determined by Epsilometer test. Following the confirmation of the efficiencies of singleplex real-time PCR methods using two different probes, a cytosine to thymine point mutation at codon 86 was detected by allelic discrimination. Of the 158 strains, 114 (72.2%) were determined to be resistant to ciprofloxacin. The MIC50 and the MIC90 of ciprofloxacin were found to be 8 and ≥32 mg/L, respectively. By real-time PCR, the presence of the mutation was confirmed in all, but one, resistant strains and the absence of the mutation was demonstrated in all, but one, susceptible strains. The rate of resistance is high among C. jejuni strains and ciprofloxacin should not be used in the treatment of such infections in Turkey. A cytosine to thymine mutation is the most frequently detected mechanism for the resistance. Real-time PCR can be used for the quick screening of the resistance.

PREVALENCE, ANTIBIOTIC AND PULSED-FIELD GEL ELECTROPHORESIS PATTERNS OF STAPHYLOCOCCUS AUREUS SMALL-COLONY VARIANTS IN CYSTIC FIBROSIS PATIENTS.

Staphylococcus aureus is the most common pathogen isolated from respiratory tract samples in cystic fibrosis (CF) cases. Rate of infection with S. aureus small-colony variants (SCVs) also is increasing in CF patients. In this study, we aimed to determine the prevalence, antibiotic susceptibility and genotypic property of S. aureus SCVs in respiratory tract samples of CF patients admitted to Istanbul Faculty of Medicine Hospital, Turkey. Among 305 respiratory tract samples from 84 CF patients, normal S. aureus isolates were present in 71% of the CF patients and S. aureus SCVs in 21%. The highest antibiotic resistance was against penicillin (82%) followed by clarithromycin (21%) in S. aureus SCVs, while resistance to levofloxacin was low (2%) in normal S. aureus isolates but was 16% in S. aureus SCVs. No mecA and mecC were detected. The S. aureus strains constituted 24 different genotypes based on pulsed field gel-electrophoresis assay. The possible existence of S. aureus SCVs that are more resistant to antibiotis than normal S. aureus should be taken into considerstion when treating CF patients for this pernicious bacterial infection.

TEM-1 AND ROB-1 PRESENCE AND ANTIMICROBIAL RESISTANCE IN HAEMOPHILUS INFLUENZAE STRAINS, ISTANBUL, TURKEY.

Resistance of 235 Haemophilus influenzae clinical isolates from Istanbul Medical Faculty Hospital, Turkey were determined against 19 antibiotics by disc diffusion method, and minimum inhibitory concentrations (MICs) of those found resistant to ampicillin, cefuroxim, chloramphenicol and meropenem were measured using E-test. Ampicillin-resistant isolates producing beta-lactamase as demonstrated by a nitrocefin assay were analyzed for the presence of TEM-1 and ROB-1 genes by PCR. Eleven percent of the isolates were resistant to ampicillin (10 µg/ml), of which 73% were beta-lactamase positive and carried TEM-1 gene, but none were positive for ROB-1 gene. All isolates susceptible to amoxicillin-clavulanate (20/10 µg/ml), azithromycin (15 µg/ml), aztreonam (30 µg/ml), cefotaxime (30 µg/ml), ceftriaxone (30 µg/ml), ciprofloxacin (5 µg/ml), levofloxacin (5 µg/ml), and telithromycin (15 µg/ml) but 24%, 15%, 4%, 4%, 2%, 1%, 1%, 0.5%, 0.5% and 0.5% were resistant to trimethoprim-sulfamethoxazole (1.25/23.75 µg/ml), tetracycline (30 µg/ml), cefaclor (30 µg/ml), clarithromycin (15 µg/ml), cefuroxime (30 µg/ml), meropenem (10 µg/ml), chloramphenicol (30 µg/ml), ampicillin-sulbactam (10/10 µg/ml), nalidixic acid (30 µg/ml), and fosfomycin (30 µg/ml), respectively. MIC values of three cefuroxime-resistant isolates was 24, 48 and > 256 µg/ml, respectively; of two meropenem-resistant strains > 256 µg/ml; and of two chloramphenicol-susceptible isolates (by disc diffusion method) 6 µg/ml (considered as intermediate susceptible). Multiple- antibiotics resistance was detected in 15% of the strains, with resistance to 2, 3, 4, 5 and 6 antibiotics in 8.5%, 4%, 2%, 0.5% and 0.5% of the isolates, respectively. By identifying beta-lactamase-negative ampicillin-resistant H. influenzae, empirical therapy with beta-lactam/beta-lactamase inhibitor combinations and second generation cephalosporins would be inappropriate for such patients (approximately 3%). Our findings will contribute to the epidemiological and clinical data regarding H. influenzae infection in Turkey.

Detection and spread of oxa-48-producing Klebsiella oxytoca isolates in Istanbul, Turkey.

Five OXA-48 producing Klebsiella oxytoca strains isolated in April-July 2010 were analyzed. Antibiotic susceptibility tests were performed using disc diffusion method and VITEK 2 system. Carbapenemase activity was investigated using the Modified Hodge test. Beta-lactamase genes were detected by PCR and blaOXA-48 was sequenced. Genetic relatedness between K. oxytoca isolates was investigated by pulse-field gel electrophoresis (PFGE). Carbapenemase activity was detected in 5 isolates by Modified Hodge test. Although all strains were resistant to ertapenem and imipenem, only one strain was also resistant to meropenem. BlaOXA-48 in 4 isolates harbored 2 or 3 other ESBL types, namely, blaTEM, blaSHV, blaCTX-M, or blaVEB. PFGE revealed 3 different pulso-types among the K. oxytoca isolates. The presence of OXA-48 carbapenemase in other species of clinical isolates should also be considered.

[Salmonella serovars isolated in Turkey up to the end of year 2011]. / Türkiye'de 2011 yili sonuna kadar izolasyonu bildirilen Salmonella serovarlari

Bacteria in Salmonella genus are separated into more than 2600 serovars. It is important that the isolated serovars and their sources are known in a certain country. This will help the identification of new Salmonella serovars that will be isolated later on. Since there is no Salmonella reference center in Turkey, Salmonella serovars isolated in Turkey were mainly reported by the articles of Aksoycan's manuscripts in various years, and in the list of Töreci and Ang in 1991. The aim of this meta-analysis was to detect and prepare a list for all the Salmonella serovars isolated from human and non-human samples in Turkey up to the end of 2011. In creating this serovar list, libraries, personal and institutional archives, theses, publication lists, books published after scientific meetings and congresses, and international and local periodicals have been explored, and members of Turkish Microbiology Society are communicated via the web site of the society and personal e-mail addresses, and their publications regarding Salmonella serovars were requested. The list also includes the modifications on the names and antigenic formulae of the serovars that were carried out in recent years. The number of serovars isolated in Turkey up to the end of 2011 is 129. Fifty three of them were isolated from humans, 38 from humans and non-human samples, and 38 from non-human samples. The total number of serovars isolated from humans is 91. Twenty seven serovars from serogrup 0:4 (B); 23 serovars from serogrup 0:7 (C1); 25 serovars from serogrup 0:8 (C2-C3); 16 serovars from serogrup 0:9 (D1); 8 serovars from serogrup 0:3,10 (E1) and 5 serovars from serogrup 0:28 (M) have been reported. Only two of the more than 2600 serovars known were isolated firstly in Turkey: S. Istanbul (8:z10: e,n,x) in 1969 and S. Adana (43:z10:1,5) in 1977. Previously, serovars containing 1 and 25 O antigen of S. Boecker ([1],6,14,[25]) were isolated in 1967 and 1971 for the first time in Turkey. In 1967, a serovar containing T1 antigen that appears during S-R alteration in Salmonella, with (T1: b: e,n,x) antigen formula has been isolated from non-human samples and was reported to be a probable S-R alteration of Salmonella Benfica. Furthermore, non-motile isolates of Salmonella enterica subsp enterica serogrup 0:7 (C1) and serogrup 0:9 (D) were reported as well. While reporting a new Salmonella isolation in a country one should not be content with only giving the name of the serovar, but also emphasize the antigenic structure and the identification method clearly.

Carbapenem resistance due to Bla(OXA-48) among ESBL-producing Escherichia coli and Klebsiella pneumoniae isolates in a univesity hospital, Turkey.

Bacterial isolates producing Class D OXA-48 carbapenemase may be missed in routine laboratory testing, allowing them to spread undetected. The purpose of the present study was to detect bla(OXA-48) among ESBL-producing Klebsiella pneumoniae and Escherichia coli isolates collected from a university hospital, Turkey. Ninety-two ESBL-producing isolates (66 E. coli, 26 K. pneumoniae) were obtained in 2010. Antibiotic susceptibility tests were performed using the disc diffusion method and VITEK 2 system. Carbapenemase activity was screened using modified Hodge test. Beta-lactamase genes were detected by PCR and bla(OXA-48)-positive amplicons were sequenced. Genetic relatedness among K. pneumoniae isolates was investigated by pulsed-field gel-electrophoresis (PFGE). Carbapenemase activity was detected in 1 E. coli and 9 K. pneumoniae isolates and 8 of the K. pneumoniae plus the E. coli isolates were resistant to ertapenem. Three K. pneumoniae and 1 E. coli isolates were resistant to imipenem. All 10 isolates were susceptible to meropenem. bla(OXA-48) was present in all 10 isolates. Additionally, 9 isolates contained at least one beta-lactamase gene, including bla(SHV') bla(CTX-M) and bla(VEB) type. PFGE revealed different karyotypes among 9 K. pneumoniae isolates suggesting that the dissemination of bla(OXA-48) gene was not spread by a single K. pneumoniae clone. Thus OXA-48-producing isolates found in carbapenem-susceptible strains according to CLSI guidelines.

[The relationship between antibiotic resistance and virulence factors in urinary Enterococcus isolates]. / Üriner Enterokok Izolatlarinin Antibiyotik Direnci ile Virülans Faktörleri Arasindaki Iliski.

Increasing multidrug resistance in nosocomial Enterococcus strains from all over the world recently enhances the need for further investigation of enterococci, especially their virulence factors. There are still many lacking parts about virulence factors of clinical enterococcus isolates. In this study, it was aimed to investigate the antibiotic resistance and the presence of potential virulence factors of 91 Enterococcus strains (59 E.faecalis, 31 E.faecium and 1 E.gallinarum) isolated from urine cultures of inpatients between January 2008-June 2010 in our hospital and also to evaluate whether a correlation existed between antibiotic resistance and potential virulence factors. The genes which encoded virulence factors of enterococci; aggregation substance (AS), enterococcal surface protein (ESP) and hyaluronidase (HYL) (asa1, esp, hyl respectively) were studied by molecular methods and haemolysin production and gelatinase activity were studied by phenotypic methods. Vancomycin resistant strains were checked for the presence of vanA and vanB genes. Eight (25.8%) E.faecium isolates were found glycopeptide resistant. In seven of these isolates resistance type was vanA and in one it was neither vanA nor vanB. High-level gentamicin and high-level streptomycin resistance rates were 74.2% and 61.3% in E.faecium strains and were 22% ve 27.1% in E.faecalis strains, respectively. Beta-lactamase production and linezolid resistance were not detected in any of the strains. E.faecium isolates were more resistant (p< 0.001-0.013) than E.faecalis isolates to all tested antibiotics except tetracycline, minocycline, doxycycline and streptogramin (p< 0.001). hyl gene positivity (p< 0.001) was found higher in E.faecium isolates whereas esp (p= 0.003) and asa1 (p< 0.001) gene positivity, haemolysin production (p=0.014) and gelatinase activity (p= 0.029) were higher in E.faecalis isolates. AS and ESP were the most frequent virulence factors, with the rates of 26.7% and 25.6%, respectively. There were 32 (35.6%) strains without any of the investigated virulence factors. We have also detected that asa1 gene positive E.faecalis isolates were more resistant to ciprofloxacin (p= 0.001), norfloxacin (p= 0.006) and levofloxacin (p= 0.001) than asa1 gene negative isolates; esp gene positive E.faecalis isolates were more resistant to doxycycline (p= 0.043) than esp gene negative isolates and hyl gene positive E.faecium isolates were more resistant to nitrofurantoine (p= 0.011) than hyl gene negative isolates. This was the first clinical sample originated study, investigating the corelation between antibiotic resistance and virulence factors in urinary Enterococcus isolates in Turkey.

Co-expression of plasmid-mediated quinolone resistance-qnrA1 and blaVEB-1 gene in a Providencia stuartii strain.

An extended-spectrum B-lactamase (ESBL)-producing Providencia stuartii isolate was studied. A qnrA1 gene co-expressing blaVEB-1 gene was detected. Both genes were transferred to the recipient strain. The ciprofloxacin MIC of recipient strain increased tenfold. The blaVEB-1 gene persisted in microorganisms in Turkey but it also spread with PMQR genes to other species. The combination of PMQR with multidrug resistant isolates producing ESBLs may compromise the use of valuable antibiotics. Serious efforts are necessary to detect PMQR determinants not only with common B-lactamases in widespread pathogens but also with uncommon forms that are encountered infrequently.

Investigation of plasmid-mediated quinolone resistance among isolates obtained in a Turkish intensive care unit.

The aim of this study was to search for three plasmid-encoded, quinolone-resistant determinants: qnrA, qnrB, and qnrS. Thus, 460 Gram-negative strains belonging to 11 different genera (clinical, 347; non-clinical, i.e., from a rectal swab, 113), of which 40% were ciprofloxacin-resistant, were recovered from patients in an intensive care unit at the Istanbul Medical Faculty, Turkey, in the years 2000 and 2006. PCR with primers specific for qnrA, qnrB, and qnrS genes and primers specific for a series of ESBL genes were used. One qnrB1 and two qnrS1 genes were identified in three ESBL-positive isolates, whereas no qnrA-positive strain was found. The qnrB1 determinant was identified in a ciprofloxacin-susceptible Enterobacter cloacae isolate that expressed CTX-M-15 beta-lactamase. Two qnrS1-determinants were found in two ciprofloxacin-susceptible E. cloacae isolates that were clonally related, but that had been isolated from different patients; both of these isolates expressed the same ESBL, CTX-M-3. This study detected the first plasmid-mediated quinolone-resistance determinants qnrB1 and qnrS1, among clinical strains obtained from patients in Turkey.

Genotype and antibiotic susceptibility patterns of Pseudomonas aeruginosa and Stenotrophomonas maltophilia isolated from cystic fibrosis patients.

The purpose of this study was to type the Pseudomonas aeruginosa and Stenotrophomonas maltophilia isolates recovered from cystic fibrosis (CF) patients by random amplified polymorphic DNA (RAPD)-PCR and to determine the antibiotic susceptibility of these strains. P. aeruginosa (n=49), and S. maltophilia (n=11) isolates which had been recovered from 16 and 8 patients, respectively, during a 1-year period were investigated. Three primers were used for RAPD-PCR typing. Antibiotic susceptibility testing of all isolates was performed by the disc diffusion method. RAPD-PCR analysis revealed 21 (P. aeruginosa) and 9 (S. maltophilia) different genotypes. According to the antimicrobial susceptibility results, the P. aeruginosa and S. maltophilia strains were cumulated into 24 and 11 groups, respectively. The CF patients were colonized or infected with P. aeruginosa strains of single or sometimes multiple genotypes which remained stable over several months. Our results also revealed that cross-colonization might be possible among the patients who are followed up at the same center. Piperacillin-tazobactam for P. aeruginosa and trimethoprim-sulfamethoxazole for S. maltophilia were found to be the most active antibiotics according to our results.

Group A beta hemolytic streptococcal infections and obsessive-compulsive symptoms in a Turkish pediatric population.

The purpose of the present study was to evaluate obsessive-compulsive disease (OCD) in Turkish Children who had group A beta hemolytic streptococcal (GABHS) infections and those who had not. Thirty-one children and adolescents (the study group) were compared with 28 children and adolescents. The Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) scores were rated between study group and control group. The mean score, obsession and compulsion scores of CY-BOCS in the study group were significantly higher than they were in the control group (P < 0.05). The GABHS infections should be assessed in the etiology of OCD in children. Considering GABHS infections may help the treatment of OCD.