Introduction: In this study, we retrospectively evaluated the annual distribution, antimicrobial resistance profiles, and specimen type distribution of Corynebacterium striatum isolates obtained from clinical specimens over an eight-year period in a university hospital. Materials and Methods: The study was conducted on C. striatum isolates obtained from clinical specimens submitted to our microbiology laboratory between 2016 and 2024. All isolates were recovered from patients and identified using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing was performed using the Kirby-Bauer disk diffusion method and interpreted according to the guidelines of the European Committee on Antimicrobial Susceptibility Testing. Data were analyzed using Statistical Package for the Social Sciences Statistics (version 20.0, IBM, Chicago, IL, USA). Results: A total of 786 C. striatum isolates were evaluated. A statistically significant increase in isolate numbers was observed over the years (slope= 25.100; p= 0.001). The most common specimen types were wound (44.4%), blood (24.5%), and sputum (21.0%) cultures. The highest resistance rates were observed for penicillin (97.9%), ciprofloxacin (95.9%), clindamycin (95.9%), rifampin (95.0%), and tetracycline (90.7%). Linezolid resistance was low (1.3%), and no vancomycin-resistant strains were detected. Additionally, a significant increasing trend was observed in Corynebacterium amycolatum and Corynebacterium coyleae isolates as well (p< 0.05). Conclusion: C. striatum has emerged as a multidrug-resistant nosocomial pathogen, increasingly isolated from clinical specimens, particularly in centers with a high population of immunosuppressed patients. These findings highlight the need for careful planning of empirical treatment strategies and the routine implementation of antimicrobial susceptibility testing.
Introduction: Measles is a highly contagious, vaccine-preventable disease and remains a major public health concern worldwide. Maintaining herd immunity plays a critical role in preventing outbreaks and achieving elimination targets. This study aimed to evaluate the relationship between serological immunity to measles and age, sex, and nationality among individuals admitted to Ondokuz May & imath;s University Medical Faculty Hospital, and to investigate changes in immunity status over the years. Materials and Methods: Data from a total of 9817 patients, including measles serology results, age, sex, nationality, and test year, were retrospectively recorded. Statistical analyses were performed using Statistical Package for the Social Sciences for Windows, v22.0 (SPSS Inc., Chicago, IL, USA). Results: Overall, 60.9% of patients were found to be immune to measles. The mean age of immune individuals was significantly higher compared to non-immune individuals (p< 0.05). Immunity rates by age group were as follows: 0-5 years 61.6%, 6-18 years 46.0%, 19-35 years 60.7%, 36-55 years 88.5%, and >= 56 years 89.0%. Immunity was higher in males compared to females, and also significantly higher in foreign nationals (p< 0.05). Conclusion: Our study revealed low measles seropositivity, particularly among young adults and women of childbearing age. These findings indicate that these groups pose a critical risk to the maintenance of herd immunity. Therefore, identifying at-risk groups and implementing targeted vaccination strategies are essential.
Introduction: The worldwide spread of multidrug-resistant bacteria is one of the greatest threats to global health. In recent years, it has become necessary to determine carbapenemase types in selected patient groups, as the activity of new antibiotics developed against these multidrug-resistant bacteria varies by carbapenemase type. In our study, we aimed to evaluate the performance of the CPO Emerge Panel (CRE panel) in determining the carbapenemase type of carbapenem-susceptible Klebsiella pneumoniae (non-CRKP) and carbapenem-resistant K. pneumoniae (CRKP) isolates, to assess its added value in routine diagnostic workflows, and to examine its agreement with polymerase chain reaction (PCR). Materials and Methods: K. pneumoniae isolates grown in blood cultures were selected retrospectively from the last isolate. Carbapenemase activity of the isolates was investigated by mCIM test and carbapenemase genes of the isolates (blaOXA-48-like, blaNDM-like, blaKPC, blaVIM and blaIMP) were investigated by PCR method. In our study, identification of all isolates at species level, determination of carbapenemase activities and Ambler classification were performed by CRE panel. Results: A total of 134 clinical K. pneumoniae isolates (106 carbapenem resistant, 28 carbapenem susceptible) were included in the study. According to the results of the conventional PCR study performed to determine the carbapenem resistance genes of 106 isolates with positive carbapenemase activity; 46 isolates were found to be positive for bla OXA-48 alone, 19 isolates were positive for bla KPC alone, 15 isolates were positive for bla NDM alone. Combined positivity was observed in the remaining 25 isolates. Among the 97 isolates classified according to the CRE panel results, carbapenemase classes of 72 (74.22%) isolates were in parallel with the PCR results (45 isolates were classified as group D, 11 isolates as group B and 16 isolates as group A). The kit correctly identified 72 (90%) of 80 isolates carrying a single type of carbapenemase. The CRE panel showed excellent sensitivity and specificity (100%) in detecting the presence of carbapenemases compared to PCR, with the highest sensitivity for carbapenemase classification observed in the detection of isolates producing class D OXA-48-like carbapenemases (kappa= 0.97: excellent agreement) and the lowest sensitivity in the detection of isolates producing class B NDM carbapenemases (kappa= 0.75: good agreement). Conclusion: In conclusion, we believe that the application of the CRE panel in selected patient groups and within established algorithms will have a positive impact on laboratory workflows as well as therapeutic and infection control decisions.
Introduction: This study aimed to evaluate the demographic and seasonal distribution of tick species isolated from individuals who sought medical attention due to tick bites in Ankara and its surrounding regions between 2017 and 2024. The goal was to identify risk groups, reveal annual and seasonal variations, and contribute to the development of targeted public health strategies. Material and Methods: This retrospective study evaluated tick samples removed from individuals who sought medical attention at healthcare facilities in Ankara and its surrounding areas due to tick bites between 2017 and 2024. The data obtained were analyzed in terms of demographic characteristics, seasonal distribution, and changes over the years. Results: A total of 419 ticks were removed from 410 patients. Among the 386 identified samples, Hyalomma spp. was the most common genus (60.9%), followed by Haemaphysalis spp. (17.1%), Rhipicephalus spp. (10.9%), Ixodes spp. (8.5%), and Dermacentor spp. (2.6%). Tick contact peaked during the summer (65.2%) and was lowest in winter (2.9%) (p< 0.05). The 26-40 age group had the highest incidence (19.8%), while 25% of all cases occurred in children. Haemaphysalis spp. were predominantly found in the 0-6 age group. A significant decline in cases was observed during the coronavirus diseases-2019 pandemic (2020-2021), with a rebound in 2023-2024. Conclusion: Tick exposure in Central Anatolia demonstrates clear seasonal and age-related patterns. The widespread detection of Hyalomma spp. across all age groups underlines the vector potential of this genus. These findings highlight the need for regional awareness programs and preventive strategies, particularly for children and rural populations.
Introduction: Vaccination holds great importance in the fight against diseases caused by the human papillomavirus (HPV). In this study, the knowledge levels, attitudes, and behaviors of physicians and nurses from various specialties and positions regarding HPV-related diseases and the HPV vaccine were evaluated. Materials and Methods: A total of 204 volunteers, including faculty members, specialist physicians, research assistants, and nurses, participated in the study. Participants were asked to complete an online survey form consisting of 13 questions, including demographic data and 12 questions that measured their knowledge about HPV and its vaccine. Data were analyzed using Statistical Package for the Social Sciences for Windows (v20.0; IBM Corp., Armonk, NY, USA). Results: Of the participants, 54.9% recommended the HPV vaccine to their patients and relatives. While 45.6% of nurses stated that they recommended the vaccine, 58.5% of physicians reported doing so. Among physicians, the rate of recommending the vaccine was higher among research assistants. When the evaluation was conducted across specialties, gynecologists and obstetricians had the highest rate of recommending the vaccine. Among those who did not recommend the vaccine, the majority stated, "I do not have enough knowledge or experience regarding the HPV vaccine."Among the participants, 10.8% believed that HPV does not cause disease in men, 7.8% thought the vaccine could not be administered to men, 12.7% believed there is an effective antiviral treatment for HPV, and 21.6% thought the vaccine also protects against other sexually transmitted diseases. in 17 patients (1.41%), with confirmed HIV-HCV coinfection in six of them. All coinfected patients received appropriate treatment. Conclusion: The HPV vaccine has been emphasized for years in our country. For society to become informed and conscious about this issue, healthcare professionals must first have accurate knowledge and apply it in practice. Greater importance should be placed on this topic; gaps in knowledge must be identified, and targeted training programs should be organized.
Introduction: Enterococci are gram-positive, opportunistic pathogens that can be found in a wide variety of environmental settings. They cause many infections, such as sepsis, urinary tract infections, and endocarditis, in immunocompromised individuals and have developed resistance to currently used antibiotics. One alternative treatment method is bacteriophage (phage) therapy. The aim of our study is to isolate a new lytic phage against Enterococcus faecalis strains and determine its genomic characteristics. Materials and Methods: In this study, the E. faecalis phage CTF3 isolated from wastewater against the E. faecalis ATCC 29212 strain was obtained using the double-layer agar method; its whole genome was sequenced, and it was compared with other Enterococcus phages. Results: The E. faecalis CTF3 phage isolated in this study was identified as 40.215 base pairs in length and circular in structure. A total of 63 structural proteins were identified in the phage genome. Considering the phylogenetic placement and taxonomic classification of the E. faecalis CTF3 phage, it is concluded that the isolated phage may be a novel Enterococcus phage belonging to the class Caudoviricetes and the genus Efquatrovirus. Conclusion: A new lytic phage effective against E. faecalis, a nosocomial infection agent, has been isolated from wastewater and its whole genome characteristics have been characterized. It is thought that the data obtained from this study could guide clinicians in creating a phage library for future phage therapy applications and clinical use.
Introduction: This study investigated the prevalence and antimicrobial resistance profiles of Acinetobacter baumannii strains isolated from a tertiary intensive care unit between 2023 and 2025. Materials and Methods: Between January 2023 and August 2025, A. baumannii strains isolated from various clinical specimens in a tertiary intensive care unit were retrospectively analyzed. Identification and antibiotic susceptibility testing of the isolates were performed using the BD Phoenix 100 M50 (Becton Dickinson Company, USA) automated system, and the results were interpreted according to the standards of the European Committee on Antimicrobial Susceptibility Testing. Only one isolate per patient was included in the study. Results: A total of 566 A. baumannii isolates were evaluated. The annual isolation rates were 13.7% in 2023, 12.5% in 2024, and 17.5% in 2025, with an overall three-year average of 14.7%. Of these isolates, 77.4% were obtained from tracheal aspirates and 16.6% from blood cultures. The lowest resistance rates were observed for colistin (10.2%) and tigecycline (11.4%), while resistance rates exceeded 90% for carbapenems, aminoglycosides, and fluoroquinolones. Trend analysis revealed a significant decrease in tigecycline resistance (p< 0.001), whereas significant increasing trends were observed for cefoperazone-sulbactam, gentamicin, fluoroquinolones, cephalosporins, and carbapenems. Conclusion: A. baumannii remains a clinically significant pathogen in intensive care units and exhibits high resistance rates, particularly against broad-spectrum antibiotics. In our study, colistin and tigecycline were observed to retain relative activity. Regular surveillance of resistance patterns and the revision of empirical treatment protocols in light of these data may contribute to reducing mortality and morbidity rates.
Hand-foot-mouth disease (HFMD), one of the most common childhood diseases, is characterized by rashes on the hands and feet and lesions in the mouth and is rarely seen in adults. In this case, it was aimed to emphasize that HFMD can be reported in adults, and its clinical course can be severe. A 39-year-old male patient presented to the hospital emergency department with complaints of fever, myalgia, arthralgia, fatigue, headache, and sore throat. During the initial clinical examination, vesicular lesions were observed around the mouth, on the soft palate and oropharynx, on the palms of the hands, and on the feet. According to the laboratory findings, an increase in C-reactive protein was detected, while the white blood cell count and aspartate aminotransferase/alanine aminotransferase levels were normal. Real-time polymerase chain reaction detected coxsackievirus A16. The fever was controlled with paracetamol without any specific treatment. The case demonstrated that HFMD, a childhood infection, can be observed symptomatically in adults. Hand-foot-mouth disease should not be overlooked when considering similar rashes in diagnosis.
Introduction: Certain inflammatory, hematological, immunological, and virological conditions contribute to chronic inflammation and have been associated with depression and anxiety in people living with human immunodeficiency virus (HIV) (PLWH). This study aimed to investigate the relationships between interleukin-6 (IL-6), cystatin C (Cys C) and D-dimer levels and the presence of depression or anxiety in PLWH. Material and Methods: People living with human immunodeficiency virus who had an HIV RNA level of <50 copies/mL and a creatinine clearance (CrCl) >= 60 mL/min, estimated using the Cockcroft-Gault equation over the past year, and who were not using any psychiatric medications were included in this descriptive, cross-sectional study. The Beck Depression Inventory and Beck Anxiety Inventory were administered to assess symptoms of depression and anxiety. Blood samples for the analysis of biological parameters were collected concurrently. Results: The average age of the 147 patients included in the study was 41.9 +/- 10.2 years (range= 21-70), and 92.5% (n= 136) were male. Depression was identified in 53.7% (n= 79) of the participants. In multivariate analysis, an HIV-RNA level >500.000 copies/ mL at the time of diagnosis was found to be a significant predictive risk factor for future depression (p= 0.024; Odds ratio= 2.324; 95% CI= 1.116-4.839). However, no significant associations were observed between IL-6, Cys C, D-dimer and other inflammatory parameters and the presence of depression or anxiety. Conclusion: PLWH who present with high viremia at the time of diagnosis should be closely monitored for the development of depression. However, among PLWH who achieve virological success, inflammatory markers do not appear to be associated with depression or anxiety.
Introduction: Staphylococcus aureus is a microorganism of increasing importance among community-and hospital-acquired pathogens. This study aimed to identify factors affecting prognosis by examining the epidemiological, clinical, and laboratory characteristics of patients with S. aureus bacteremia. Materials and Methods: This is a descriptive study that included 170 patients diagnosed with S. aureus bacteremia at a tertiary hospital between January 1, 2015, and January 1, 2020. Patients under 18 years of age and those with non-S. aureus growth in their cultures were excluded. Logistic regression analysis was used to determine factors associated with mortality. Results: Ninety-four (55.3%) of the patients were male. The mean age was 66.7 +/- 12.8 (18-95) years. Blood cultures revealed methicillin-susceptible S. aureus in 126 patients (74%), and methicillin-resistant S. aureus in 44 patients (26%). At least one complication developed in 33 patients (19%). The mortality rate in patients with complications (36.5%) was higher than in those without complications (12.1%). Appropriate antibiotic treatment was initiated within 24 hours in 114 patients (67.1%), between 24 and 48 hours in 18 patients (10.6%), and later than 48 hours in 19 patients (11.2%). Antibiotic treatment was changed after diagnosis in 61 patients (35.9%). Persistent bacteremia (lasting longer than seven days) was detected in 21 patients (21.4%). The mean duration of treatment was 12.4 +/- 7.8 days. One hundred twenty-six patients (68%) survived, while 54 (32%) died. Mortality was found to be higher in patients with fever and hospital-acquired bacteremia at the time of diagnosis, and lower in patients with confusion and invasive mechanical ventilation. Conclusion: S. aureus bacteremia is a significant problem due to its complications and treatment challenges. The study found that high fever and hospital-acquired bacteremia are factors associated with mortality. Close monitoring of patients with fever and hospital-acquired S. aureus bacteremia is recommended in terms of mortality.
Drug-induced liver injury (DILI) is a serious and commonly encountered clinical complication, the diagnosis of which is usually established by exclusion. Antibiotics, particularly beta-lactam agents, are among the leading causes of DILI. Meropenem is a widely used broad-spectrum carbapenem antibiotic. This report presents a case of acute hepatocellular liver injury that developed within 24 hours after initiation of meropenem for the treatment of pneumonia in an 85-year-old patient. Viral hepatitis, autoimmune diseases, and other potential causes of liver injury were comprehensively excluded. In the presence of marked elevations in liver enzymes, meropenem was discontinued, after which the biochemical abnormalities were observed to resolve spontaneously without any specific treatment. Reports of meropenem-induced liver injury are rare in the literature; the rapid onset and reversibility observed in this case underscore the importance of drug discontinuation in management. In clinical practice, awareness of the risk of hepatotoxicity associated with meropenem use and adoption of a multidisciplinary approach in similar cases are of great importance.
Introduction: Serratia marcescens is a gram-negative bacterium that causes severe infections and contributes to increased morbidity and mortality due to rising antimicrobial resistance. This study evaluated the prevalence of extended-spectrum beta-lactamase (ESBL) and plasmid-mediated quinolone resistance (PMQR) genes. Materials and Methods: A total of 640 S. marcescens strains isolated from various clinical samples over five years were included in this study. The strains were identified by mass spectrometry, and their antimicrobial susceptibility was determined using an automated system (Becton, Dickinson and Company, Franklin Lake, USA) and the Kirby-Bauer disk diffusion method, with evaluation based on The European Committee on Antimicrobial Susceptibility Testing 2022 criteria. Seventy strains that exhibited intermediate (I) or resistant (R) profiles to third-generation cephalosporins or quinolones were further screened by in-house polymerase chain reaction for beta-lactamase genes (blaTEM, blaSHV, blaCTX-M, blaOXA), and PMQR genes (qnrA, qnrB, qnrS, aac(6')-Ib-cr, and qepA), as well as for integron content. The blaCTX-M gene and the variable region of class 1 integrons were analyzed by Sanger sequencing. Results: The detected resistance genes included 5.7% (n= 4) blaTEM, 2.9% (n= 2) blaSHV, 1.4% (n= 1) blaCTX-M-15, 4.3% (n= 3) qnrS, 2.9% (n= 2) aac(6')-Ib-cr, and 4.3% (n= 3) intI1. The blaOXA, qnrA, qnrB, qepA, and intI2 genes were not detected. Two strains harboring class 1 integrons contained gene cassettes including aadA2, dfrA12, and ANT(2")-Ia. Conclusion: This study provides valuable epidemiological data on ESBL production and quinolone resistance genes among S. marcescens strains in our region, indicating an overall low level of resistance to carbapenems and aminoglycosides, but a noticeable increase in resistance to third-generation cephalosporins and quinolones over the years. Further studies and surveillance are needed to better guide the use of antibiotics in S. marcescens infections.
Introduction: The present in vitro study was conducted to evaluate the effects of different orthodontic wire materials and cross-sectional geometries on Streptococcus mutans biofilm formation and bacterial viability. Materials and Methods: The study examined three distinct wire materials: Stainless steel (SS), nickel-titanium (NiTi), and copper containing nickel-titanium (Cu-NiTi). Each material was prepared in two cross-sectional forms: round (0.016 '') and rectangular (0.016 '' & times; 0.022 ''). Twelve samples from each group were incubated with S. mutans ATCC 25175 strain at 37 degrees C and 5% CO2 for 24 hours. The measurement of biofilm biomass was conducted by means of crystal violet staining at OD570. The assessment of bacterial viability was conducted through the quantification of colony-forming units (CFU/mL) following a process of vortex-ultrasonication separation. The subsequent analysis of the data was conducted using two-way analysis of variance (Robust analysis of variance) and Holm-corrected post-hoc tests. The level of statistical significance was set at p< 0.05. Results: The composition of the wire material and the cross-sectional shape of the wire exhibited a significant impact on the accumulation of biofilm and bacterial adhesion (p< 0.001). Rectangular cross-section NiTi wires demonstrated the highest OD570 and CFU values, while Cu-NiTi (both cross-sections) and round cross-section SS wires exhibited the lowest bacterial loads (p< 0.001). A higher degree of biofilm accumulation was observed in rectangular cross-section wires compared to round cross-section wires (p< 0.001). Conclusion: The composition and geometry of the wire material jointly affect bacterial adhesion on orthodontic arch wires. In addition, Cu-NiTi wires demonstrated a reduced tendency for biofilm accumulation, an outcome that can be attributed to the inherent antimicrobial properties of copper. The findings emphasize the significance of material selection and wire design in minimizing microbial colonization during orthodontic treatment.
Introduction: Candida (Candidozyma) auris is a fungal pathogen that has drawn attention due to its high antifungal resistance rates, ability to persist on abiotic surfaces, and potential to cause healthcare-associated outbreaks. In addition to clade I, II, III, and IV reported from South Asia, East Asia, Africa, and South America, respectively, clade V has been confirmed in patients in Iran and clade VI in Singapore. The variabilities in antifungal efficacy and clinical presentation across different clades of C. auris underscore the importance of clade identification. Whole genome sequencing (WGS) is the gold standard for determining which clade C. auris isolates belong to. However, WGS is expensive and requires bioinformatics expertise. Cost-effective clade identification may be performed using the polymerase chain reaction (PCR)-based clade identification (ClaID) method. The aim of this study is to determine the clade of the clinical C. auris strains isolated at our center using the ClaID method and to determine the in vitro antifungal susceptibility profiles of the isolates. Materials and Methods: In this study, the ClaID method was applied to detect the clades of 28 C. auris isolates which were collected at Ankara Bilkent City Hospital between October 2021 and March 2023. The minimum inhibitory concentration (MIC, mg/L) values of the isolates for fluconazole, amphotericin B, anidulafungin, micafungin, itraconazole, voriconazole, posaconazole, and flucytosine were determined using the European Committee on Antimicrobial Susceptibility Testing (EUCAST) microdilution method. The MIC values obtained were interpreted according to the breakpoints and epidemiological cut off values documented by EUCAST or the Centers for Disease Control and Prevention tentative breakpoints. Results: The ClaID method identified all isolates as belonging to clade I. All isolates were resistant to fluconazole and susceptible-increased exposure to amphotericin B. One isolate was assessed as resistant to echinocandins (anidulafungin and micafungin). Conclusion: The C. auris isolates in this study were determined to belong to Clade I and our susceptibility results were consistent with the expected high fluconazole resistance for this clade. In one C. auris isolate, echinocandin resistance confirmed with a reference method was detected for the first time in our country. The results obtained in this study regarding clade analysis and in vitro antifungal susceptibility profiles are of particular significance as a remarkable contribution to the limited reported data in T & uuml;rkiye.
