Antibiotic Susceptibility Test Results Research Articles

Rapid immunochromatographic detection of carbapenemases directly from positive blood cultures in patients colonized by carbapenemase-producing bacteria

ObjectivesCarbapenem resistance is increasing worldwide. Earlier detection of this resistance, combined with appropriate treatment, could improve the prognosis of bloodstream infection. This study aims to evaluate the detection of carbapenemase producing gram-negative bacteria directly from positive blood cultures to quickly adapt antibiotic therapy before the results of antibiotic susceptibility testing are available. MethodA prospective single-center study was conducted over a five-month period at Lille University Hospital. Carbapenemase detection by immunochromatographic testing was performed directly from positive blood cultures with gram-negative rods of thirty-five patients previously colonized with carbapenemase-producing bacteria. ResultsAmong these thirty-five positive blood cultures, 15 carbapenemase-producing strains were directly detected, mainly OXA-48 and NDM. This rapid procedure provided results in less than one hour, compared to several hours for conventional methods. Of the patients with infections caused by carbapenemase-producing isolates, 67% (10 patients) received inappropriate empiric treatment, highlighting the potential of the rapid test to adjust antibiotic therapy sooner. ConclusionsCarbapenemase detection by immunochromatographic testing directly on blood culture pellets is reliable and can lead to early adaptation of antibiotic therapy in these severe infections.

Detection, isolation and virulence characterization of Helicobacter suis from pork products aimed to human consumption

Helicobacter suis is the most common non-H. pylori gastric Helicobacter species found in humans. Infection is associated with gastritis, peptic ulcer, gastric MALT lymphoma and neurodegenerative disorders, particularly Parkinson's disease. However, the pathogenicity of this species is still a matter of research, and results of virulence studies and antibiotic susceptibility tests tend to vary between strains. Cholesterol α-glucosyltransferase (αCgT), a known H. pylori virulence factor, appears to be present in most clinical H. suis isolates. The ability to form biofilms also plays a crucial role in the pathogenesis of H. pylori. However, no reports have been published on this ability in H. suis.H. suis is considered an emerging zoonotic pathogen, with pigs being the main source of human infection. However, there is very little information on its presence in pork, mainly due to the difficulties of its culture. Therefore, our aim was to determine the prevalence of H. suis in pork products from our geographical area by PCR and fluorescence in situ hybridisation (FISH), as well as to isolate the bacteria and determine the antibiotic susceptibility patterns, the presence of the αCGT gene and the ability of the isolates to form biofilms.Overall, H. suis was detected in 20 of the 70 (28.6 %) samples analyzed. In 3 of them, H. suis was isolated. The αCGT gene was detected in all isolates and two of them showed a multiresistance pattern. The H. suis reference strain and two of the isolates showed “strong” to “moderate” in vitro biofilm formation ability under optimal growth conditions.Our results seem to indicate that H. suis is significantly prevalent in pork products. The combination of culture with FISH and/or mPCR proved to be a rapid and specific method for the detection, identification and direct visualization of cultivable H. suis cells from pork food products.

MOLECULAR ANALYSIS OF THE MCR-1 GENE IN PSEUDOMONAS AERUGINOSA AND ACINETOBACTER BAUMANII STRAINS

Objective: The emergence of antibiotic resistance in Pseudomonas aeruginosa and Acinetobacter baumanii isolates poses serious risks to public health. Our study aimed to investigate the presence of colistin resistance and mcr-1 gene positivity in these isolates. Material and Method: Culture, biochemical tests, antibiotic susceptibility tests, and molecular tests were used to isolate and identify P. aeruginosa and A. baumanii strains. Result and Discussion: A sum of 156 clinical isolates of Pseudomonas aeruginosa (n = 89) and Acinetobacter baumannii (n = 67) were obtained using the 550 clinical samples collected in one year from the largest hospital in Van, Turkey. The results of antibiotic susceptibility tests showed that approximately 82.8% of P. aeruginosa and 94.6% of A. baumannii strains were multidrug-resistant (MDR). Colistin resistance was detected in 11.23% (10/89) of P. aeruginosa isolates and 11.94% (8/67) of A. baumannii isolates using agar dilution and microdilution methods. Out of the 18 colistin-resistant isolates, the mcr-1 gene was detected in three P. aeruginosa and two A. baumannii strains. The detection of plasmid-mediated colistin resistance in P. aeruginosa and A. baumannii is of great concern due to the high potential for colistin resistance to spread in clinical settings. Understanding the unique circumstances of worldwide colistin resistance can be facilitated by promoting the creation of quick processes for identifying colistin resistance profiles and putting them into practice in hospital laboratories. Colistin and carbapenem treatment are two effective ways to treat emerging resistant super-microbes and slow down the emergence of resistance.

Comparative antibiotic resistance in urine cultures before and after the SARS-CoV-2 Pandemic

An epidemiological surveillance study was conducted at Laboratorios Ruiz (member of Synlab México group) in Puebla, Mexico that included the comparison of the antibiotic susceptibility test results of bacteria isolated from urine cultures at two different periods, between 2017 and 2021. There was an increase in the resistance to beta-lactams in E. coli and K. pneumoniae while a decrease in resistance to aminoglycosides in E. faecalis. The COVID-19 pandemic may have contributed to the increased antibiotic resistance trends.

Artificial Intelligence-Clinical Decision Support System in Infectious Disease Control: Combatting Multidrug-Resistant Klebsiella pneumoniae with Machine Learning.

The World Health Organization has identified Klebsiella pneumoniae (KP) as a significant threat to global public health. The rising threat of carbapenem-resistant Klebsiella pneumoniae (CRKP) leads to prolonged hospital stays and higher medical costs, necessitating faster diagnostic methods. Traditional antibiotic susceptibility testing (AST) methods demand at least 4 days, requiring 3 days on average for culturing and isolating the bacteria and identifying the species using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), plus an extra day for interpreting AST results. This lengthy process makes traditional methods too slow for urgent clinical situations requiring rapid decision-making, potentially hindering prompt treatment decisions, especially for fast-spreading infections such as those caused by CRKP. This research leverages a cutting-edge diagnostic method that utilizes an artificial intelligence-clinical decision support system (AI-CDSS). It incorporates machine learning algorithms for the swift and precise detection of carbapenem-resistant and colistin-resistant strains. We selected 4307 KP samples out of a total of 52,827 bacterial samples due to concerns about multi-drug resistance using MALDI-TOF MS and Vitek-2 systems for AST. It involved thorough data preprocessing, feature extraction, and machine learning model training fine-tuned with GridSearchCV and 5-fold cross-validation, resulting in high predictive accuracy, as demonstrated by the receiver operating characteristic and area under the curve (AUC) scores, laying the groundwork for our AI-CDSS. MALDI-TOF MS analysis revealed distinct intensity profiles differentiating CRKP and susceptible strains, as well as colistin-resistant Klebsiella pneumoniae (CoRKP) and susceptible strains. The Random Forest Classifier demonstrated superior discriminatory power, with an AUC of 0.96 for detecting CRKP and 0.98 for detecting CoRKP. Integrating MALDI-TOF MS with machine learning in an AI-CDSS has greatly expedited the detection of KP resistance by approximately 1 day. This system offers timely guidance, potentially enhancing clinical decision-making and improving treatment outcomes for KP infections.

Innovative strategies against superbugs: Developing an AI-CDSS for precise Stenotrophomonas maltophilia treatment

ObjectivesThe World Health Organization named Stenotrophomonas maltophilia (SM) a critical multi-drug resistant threat, necessitating rapid diagnostic strategies. Traditional culturing methods require up to 96 h, including 72 h for bacterial growth, identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) through protein profile analysis, and 24 h for antibiotic susceptibility testing. In this study, we aimed at developing an artificial intelligence-clinical decision support system (AI-CDSS) by integrating MALDI-TOF MS and machine learning to quickly identify levofloxacin and trimethoprim/sulfamethoxazole resistance in SM, optimizing treatment decisions. MethodsWe selected 8,662 SM from 165,299 MALDI-TOF MS-analysed bacterial specimens, collected from a major medical centre and four secondary hospitals. We exported mass-to-charge values and intensity spectral profiles from MALDI-TOF MS .mzML files to predict antibiotic susceptibility testing results, obtained with the VITEK-2 system using machine learning algorithms. We optimized the models with GridSearchCV and 5-fold cross-validation. ResultsWe identified distinct spectral differences between resistant and susceptible SM strains, demonstrating crucial resistance features. The machine learning models, including random forest, light-gradient boosting machine, and XGBoost, exhibited high accuracy. We established an AI-CDSS to offer healthcare professionals swift, data-driven advice on antibiotic use. ConclusionsMALDI-TOF MS and machine learning integration into an AI-CDSS significantly improved rapid SM resistance detection. This system reduced the identification time of resistant strains from 24 h to minutes after MALDI-TOF MS identification, providing timely and data-driven guidance. Combining MALDI-TOF MS with machine learning could enhance clinical decision-making and improve SM infection treatment outcomes.

The Impact of Reporting the Same-Day Identification and Antibiotic Susceptibility Test Results on the Treatment of Bloodstream Infections.

The rise of antibiotic-resistant organisms necessitates the implementation of rapid identification (ID) and antibiotic susceptibility testing (AST) methods for patient management. We aimed to analyze how rapid ID and AST reporting influenced clinicians' treatment decisions. Bacteria were identified directly from positive blood cultures (BC) using serum separator tubes and MALDI-TOF MS. EUCAST rapid antibiotic susceptibility testing (RAST) method was performed for AST. The impact of rapid ID and AST reports on clinician treatment decisions was evaluated through clinical documentation. The appropriateness of antimicrobial therapy and interventions was assessed according to institutional antimicrobial prescribing guidelines, AST results, and clinical data. A total of 128 BC bottles from 86 patients underwent processing. The rapid ID method was successful in 105 (82.1%) bottles obtained from 76 patients. The rapid ID results were reviewed by the Infectious Diseases Team on the same day for 55 (72.4%) of the 76 patients. Following the evaluation, new treatments or interventions were recommended for 28 (36.8%) patients. RAST results were available for 24 patients. The susceptibility profile of seven patients was assessed by the Infectious Diseases Team on the same day. Antimicrobial treatment was escalated in four cases, and de-escalation was made in two based on RAST results. If all rapid results had been assessed, adjustments could have been made for eight (10.5%) and eleven (14.5%) more patients, according to ID and RAST results, respectively. Implementation of rapid ID and AST may contribute to patient management. Although rapid reporting was made, some results were not evaluated by the clinician on the same day, indicating that communication between the clinician and the laboratory needs to be strengthened.

Isolation, Identification and Antimicrobial Susceptibility of some Bacterial Species Isolated from Dental Plaque

Dental plaque is a sticky bacterial film that develops on teeth producing plaque as a result. If it ‘is not removed with regular dental cleanings and daily brushing, it can initiate oral health issues such as gum diseases and dental caries. This study aimed to determine the prevailing bacterial species found in some patients’ dental plaque cases and dental caries and to analyze the antimicrobial susceptibility of the obtained bacteria. A total of 60samples of dental plaque were taken from patients who attended the health centres in Baghdad with different ages using cotton swabs. All gained swabs were transported to the microbiology laboratory and cultured on culture media. According to standard laboratory diagnosis protocols, primary diagnosis was performed. VITE 2Compact Automated-System (GP (and (GN (diagnosis cards used according to manufacturer company constructions (BioMérieux)to confirm the diagnosis. Antibiotic susceptibility test was done by using antibiotic disks according to Kirby-Bauer method. Out of 60samples, forty-two (70%) samples showed growth on culture media, while 18(30%) showed no growth, most of the isolates, 29(69.0%) were Gram-positive bacteria represented by Streptococcus mutans, Staphylococcus aureus, and only 13(30.9%) of isolates were Gram-negative includes Klebsiella pneumonia and Escherichia coli.According to the antibiotic susceptibility test results, Gram-positive bacteria showed high resistance against amoxicillin, Cefotaxim and erythromycin with percentages of 86.2%-and 89.6%respectively. Gram-negative bacteria showed high resistance against amoxicillin and erythromycin with percentages of 76.9%and 69.2%against Cefotaxim

Comparison of testing methods assessing the in vitro efficacy of the combination of aztreonam with avibactam on multidrug-resistant Gram-negative bacilli

BackgroundAztreonam-avibactam (ATM-AVI) combination shows promising effectiveness on most carbapenemase-producing Gram-negatives, yet standardized antibiotic susceptibility testing (AST) methods for evaluating the combination in clinical laboratories is lacking. We aimed to evaluate different ATM-AVI AST approaches.Methods96 characterized carbapenem-resistant clinical isolates belonging to 9 Enterobacterales (EB; n = 80) and P. aeruginosa (PA; n = 16) species, including 90 carbapenemase producers and 72 strains resistant to both CAZ-AVI and ATM, were tested. Paper disk elution (DE; Bio-Rad) and E-test gradient strips stacking (SS; bioMérieux) were performed for the ATM + CAZ-AVI combination. MIC Test Strip (MTS; Liofilchem) was evaluated for ATM-AVI MIC determination. Results were interpreted applying ATM clinical breakpoints of the EUCAST guidelines and compared to the broth microdilution method (Sensititre, Thermofisher).ResultsAccording to broth microdilution method, 93% of EB and 69% of PA were tested susceptible to ATM-AVI. The synergistic effect of ATM-AVI was of 95% for EB, but of only 17% for PA. The MTS method yielded higher categorical and essential agreement (CA/EA) rates for both EB (89%/91%) and PA (94%/94%) compared to SS, where the rates were 87%/83% for EB and 81%/81% for PA. MTS and SS yielded 2 and 3 major discrepancies, respectively, while 3 very major discrepancies each were observed for both methods. Concerning the DE method, CA reached 91% for EB and 81% for PA, but high number of very major discrepancies were observed for EB (n = 6; 8%) and for PA (n = 3; 19%).ConclusionsThe ATM-AVI association displayed excellent in vitro activity against highly resistant clinical Enterobacterales strains. MTS method offers accurate ATM-AVI AST results, while the SS method might serve as better alternative then DE method in assessing the efficacy of ATM + CAZ-AVI combination. However, further investigation is needed to confirm the methods' ability to detect ATM-AVI resistance.

Identification and florfenicol-treatment of pseudomonas putida infection in gilthead seabream (Sparus aurata) fed on tilapia-trash-feed

The present study aimed to determine the major cause of the high mortality affecting farmed gilthead seabream (Sparus aurata) and controlling this disease condition. Fifteen diseased S. aurata were sampled from a private fish farm located at Eldeba Triangle, Damietta, fish showed external skin hemorrhages, and ulceration. Bacterial isolates retrieved from the diseased fish were identified biochemically as Pseudomonas putida and then confirmed by phylogenetic analysis of the 16 S rRNA gene sequence. P. putida was also isolated from three batches of tilapia-trash feed given to S. aurata. Biofilm and hemolytic assay indicated that all P. putida isolates produced biofilm, but 61.11% can haemolyse red blood cells. Based on the antibiotic susceptibility test results, P. putida was sensitive to florfenicol with minimum inhibitory concentrations ranging between 0.25 and 1.0 µg mL− 1, but all isolates were resistant to ampicillin and sulfamethoxazole-trimethoprim. Pathogenicity test revealed that P. putida isolate (recovered from the tilapia-trash feed) was virulent for S. aurata with LD50 equal to 4.67 × 107 colony forming unit (CFU) fish− 1. After intraperitoneal (IP) challenge, fish treated with 10 mg kg− 1 of florfenicol showed 16.7% mortality, while no mortality was recorded for the fish group that received 20 mg kg− 1. The non-treated fish group showed 46.7% mortality after bacterial challenge. HPLC analysis of serum florfenicol levels reached 1.07 and 2.52 µg mL− 1 at the 5th -day post-drug administration in the fish groups received 10 and 20 mg kg− 1, respectively. In conclusion, P. putida was responsible for the high mortality affecting cultured S. aurata, in-feed administration of florfenicol (20 mg kg− 1) effectively protected the challenged fish.

Isolation of aerobic bacteria from abscesses and wounds in rabbits and antibiotic susceptibility testing of Staphylococcus spp. and Pseudomonas spp. isolates

BackgroundWound infections and abscesses in rabbits are a common problem in veterinary practice and their treatment can be challenging. Bacterial culture and antimicrobial susceptibility testing are important tools in these cases. While some studies are available on bacteria associated with wound infections and abscesses in rabbits, the numbers of animals included is generally limited. Monitoring of antibiotic resistance in clinical practice is also an important part of good antibiotic stewardship. Multiple antibiotic resistances are frequently encountered in Staphylococcus and Pseudomonas spp., two groups of bacteria commonly associated with abscesses in rabbits. MethodsThis retrospective study evaluated the results of aerobic bacterial cultures and antibiotic susceptibility tests in swabs from abscesses (A) (n=541) and from skin and wounds (SW) (n=308) submitted to a commercial diagnostic laboratory. Samples submitted between January 2017 and October 2020 were included in the study. Antimicrobial susceptibility testing for Staphylococcus and Pseudomonas spp. was evaluated and compared. ResultsIn A, 465 bacterial isolates including 35 different species were isolated while 394 bacterial isolates, including 35 different species, were found in SW. The most frequently isolated bacteria were Staphylococcus spp. (A = 21.7%, SW = 36.5%) followed by Pasteurella spp. in A (13.3%) and aerobic spore-forming bacteria in SW (11.2%). Pseudomonas spp. was the third most commonly isolated genus in both sample types (A = 11.6%, SW = 8.9%). Pseudomonas aeruginosa isolated from A were more often resistant to the tested antibiotics than other Pseudomonas species. These results support the need for bacterial culture and antibiotic susceptibility testing in small mammal practice.

Characterization of Proteus Spp. And Plasmid Mediated Resistance Among Hospitalized Patients in Eku, Delta State, Nigeria

The study was conducted to analyze the occurrence and antimicrobial susceptibility profile of Proteus species in blood and wound samples from patients who visited Eku General Hospital in Delta State, Nigeria. A total of 60 samples, 30 from blood and 30 from wound, were collected for the study. The bacteria were identified through bacteriological and biochemical analyses, while antibiotic susceptibility testing was performed using the Kirby-Bauer disc diffusion method. Plasmid curing was carried out using a sub-inhibitory concentration of 10% sodium dodecyl sulfate on resistant organisms. The study found three isolates including Proteus mirabilis, P. vulgaris, and P. penneri. The results showed that P. mirabilis was the most prevalent in blood (32.3%) and wound (22.6) samples, followed by P. penneri (11.3%), and P. vulgaris (9.7%) in blood sample. The study also found that the highest rate of isolation of the bacterium occurred among individuals aged between 21-35 years, followed by 12-20 years. Result of antibiotic susceptibility test showed high level of resistance in the two most commonly prescribed antibiotics cephalosporins and ampicillin. No resistance was observed in gentamycin making it the best drug for treating empirical infections. However, resistance was mostly carried on plasmids as shown by the loss of resistance after curing by the isolates. Harbouring of resistance on plasmids as huge public health implications including but not limited to spread of resistance genes, as such measures should be put in place to prevent spread.

Antimicrobial susceptibility testing data analysis over 3 years at the Yaoundé General Hospital, Cameroon.

Antimicrobial resistance (AMR) is a major health concern with high rates in low-income countries. Bacteriology laboratories sustain the fight against AMR by providing antibiotic susceptibility testing (AST) results to ensure appropriate therapies. These laboratories generate a lot of data, which are usually used for prospective interventions. Our study conducted in a lower-middle-income hospital setting aimed to describe the profile of bacteria isolated from the specimens received over 3 years, assess their susceptibility profile and identify potential gaps or area of improvement from the analysis of our data. Monthly data were retrieved from registers for all specimens received between January 2020 until December 2022. Data were compiled and analysed using the R and WHONET software. Out of 3582 specimens received, 797 were culture positive (22.3%). Escherichia coli and Klebsiella pneumoniae were frequently isolated (30.5% and 24.2%, respectively). AST results analysis showed high resistance of Gram-negative bacteria to penams and cephems, whereas low resistance was observed to carbapenems. Susceptibility to antibiotics based on the AWaRe antibiotic classification was variable. The bacteriological profile in the various types of specimen was established and rational information to design a therapeutic protocol adapted to our hospital setting was obtained. AST results may not only be used for prospective guidance for treatment, but rather cumulative data analysis can contribute to design effective antibiotic prescriptions and improve general practices at the laboratory. This is, however, dependent on a good record-keeping, standardization of practices and collaboration between clinicians and laboratory scientists.

Clinical characteristics and risk factors for Klebsiella pneumoniae bloodstream infection in 152 immunocompetent patients.

To investigate the clinical characteristics and prognostic risk factors for Klebsiella pneumoniae bloodstream infections in immunocompetent patients. The study included patients with K. pneumoniae bloodstream infection treated in Zhongda Hospital from June 2016 to June 2021. Clinical data and antibiotic susceptibility test results were retrospectively collected and analyzed. Independent risk factors for mortality were screened using the chi-square test and multivariate logistic regression. A total of 152 patients were included in the analysis. In our cohort, 77.6% of patients were older than 60 years, and 80.9% of them had community-acquired infections. The most common complications were type 2 diabetes, hypertension, and stroke sequelae. The proportion of patients with septic shock or abscesses was 34.9% and 25.7%, respectively. There were significant differences in the site of infection, septic shock, and serum levels of procalcitonin, hypersensitive C-reactive protein, D-dimer, creatinine, and lactic acid between survivors and non-survivors (p < 0.05). Multivariate regression analysis showed that hospital-acquired infections, septic shock, length of hospital stay, and creatinine levels were independent risk factors for mortality. Antibiotic susceptibility test results indicated that clinical outcomes varied depending on bacterial sensitivity to ampicillin/sulbactam. Klebsiella pneumoniae is a common community-acquired and hospital-acquired bacteria and usually infects older people with complications such as diabetes. Nosocomial infections, length of stay, septic shock, and renal insufficiency are potentially associated with poor prognosis. Bacterial susceptibility to ampicillin/sulbactam affects prognosis.

Enterococcus faecium BACTERIOCIN EFFLUX PUMP MexA GENE AND PROMOTE SKIN WOUND HEALING IN MICE

The process involved isolating E. faecium from the gut of honeybees, screening the bacterium for bacteriocin-like inhibitory substance (BLIS), evaluating its impact on the expression of the mexA gene in multidrug-resistant (MDR) P. aeruginosa, and determining the role of bacteriocin in treating infected wounds in mice through histopathological examination. After evaluating the best circumstances for producing BLIS, it was discovered that glucose was a superior carbon source and yeast extract was the best source of nitrogen. The pH was found to be 5, the ideal incubation time was 72 hours, and ammonium sulfate salt was used for partial purification at 80% saturation. The identification of MDR P. aeruginosa isolates from pus infections was a further focus of the study. The VITEK 2 system was used to perform the identification. The results of antibiotic susceptibility tests revealed that the greatest resistance rates were found against Meropenem (83.3%) and Gentamicin (73.3%), followed by beta-lactam antibiotics (Ticarcillin, Ticarcillin/Clavulanic Acid, Piperacillin, and Aztreonam), which showed resistance in about 66.6 and 36.6% of the study isolates, respectively. Followed by Imipenem (63.3%), Ceftazidime (36.6%), and Cefepime (36.6%). The mexA gene was detected in all nine strains. The study also investigated the impact of the bacteriocin of the chosen strain on the expression of the mexA gene. An in vivo study revealed that wound healing was enhanced by treating infected wounds with E. faecium bacteriocin. Conclusion: Down-regulation and up-regulation in the expression of the genes following exposure to Bacteriocin indicate the potential of E. faecium as an effective antimicrobial agent against MDR P. aeruginosa infections.

Clinical Situation, Species Distribution, and Antibiotic Resistance of Pathogenic Bacteria and Fungi in 626 Cases of Vulvovaginitis in Hangzhou, China.

Female vulvovaginitis was one of the most common gynecological diseases. It had a great negative impact on their work and quality of life. This retrospective study evaluated the clinical and laboratory data of patients with vulvovaginitis in Hangzhou, China. To analyze the clinical situation, species distribution and antibiotic resistance of pathogenic fungi and bacteria in 626 cases of vulvovaginitis in Hangzhou. Microorganism culture, identification, and antibiotic susceptibility testing were conducted. The study aimed to provide a theoretical value for an effective treatment of vulvovaginitis. In total, 626 outpatients and inpatients diagnosed with vulvovaginitis were selected from January 2018 to January 2023. Data of all the patients were collected from the hospital's electronic medical records. Vaginal secretion was collected for testing and SPSS 25.0 software was used to perform statistical analysis. A total of 626 strains of fungi, Gram-positive, and -negative bacteria were detected. Clinical situations of patients infected with the top five pathogenic fungi and bacteria were analyzed. Pathogenic fungi and bacteria were slightly different in each age group and in each onset time group. The results of antibiotic susceptibility testing showed that the resistance rates of itraconazole and fluconazole were high and Gram- negative and -positive bacteria were multidrug resistant. Gram-negative bacteria were more sensitive to carbenicillins and compound antibiotics, while Gram-positive bacteria were sensitive to rifampicin and daptomycin. MRSA and non vancomycin-resistant strains were detected. Fungi and bacteria were usually detected as pathogenes in patients with vulvovaginitis in Hangzhou. Some factors, such as age and onset time, often affected the incidence. Pathogenic fungi and bacteria were resistant to some common antibiotics, and clinical treatments should be carried out in a timely and reasonable manner according to the results of antibiotic susceptibility testing.

Resistance profile ofEscherichia coliisolated from stool, feed, and compost sources to antibiotics in Sukabumi

Antibiotic-resistantE. coliis a growing concern in various settings, but environmental studies are rare compared to clinical research on human and animal health. This study aimed to identify the prevalence ofE. colibacteria resistant to different antibiotics in the environment by examiningE. coliresistant to cefotaxime isolated from ruminant stool, feed, and compost. The phenotyping test was conducted through antibiotic susceptibility test using Kirby-Bauer disk-diffusion method, followed by the One-Way variance (ANOVA) analysis of the antibiotic susceptibility test results. Of the 12 isolates exposed to cefotaxime, six showed resistance to this antibiotic, and all isolates, including those resistant to cefotaxime, were resistant to eight out of ten types of antibiotics. All isolates had resistance to at least two to five types of antibiotics. The phenotypic pattern between fecal isolates and non-fecal isolates did not differ significantly, except for the antibiotics amoxicillin (p≤0.05) and ampicillin (p≤0.05). The overlapping resistance patterns observed in animal feed, animal stool, and compost suggest a potential link between their microbiological compositions.

Karbapenem dirençli Gram-negatif mikroorganizmalarda seftazidim-avibaktam duyarlılıklarının değerlendirilmesi

Aims: Carbapenem-resistant Gram-negative microorganisms are gradually increasing in hospitalized patients in intensive care units and causes increased morbidity, mortality, and cost. This study aims to investigate the susceptibility of ceftazidime-avibactam (caz-avi), which has recently started to be used for the treatment of infections caused by carbapenem-resistant (CR) Gram-negative bacteria isolated from various samples received from the intensive care unit (ICU) of our hospital.&#x0D; Methods: Carbapenem-resistant Klebsiella pneumoniae (CRKP) and carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains isolated from various clinical specimens that were sent to our laboratory between January 1st, 2021, and October 30th, 2022, were retrospectively evaluated in the study. The culture and antibiogram results of the samples were received over the laboratory information system (LIS) and evaluated using statistical analyses. Ceftazidime-avibactam susceptibility was studied using the disc diffusion method. &#x0D; Results: Ceftazidime-avibactam antibiotic susceptibility test results of 352 (69.4%) CRKP and 155 (30.6%) CRPA strains isolated from various clinical samples from the ICU of our hospital were analyzed. Of the CRKP strains, 313 (88.9%) were found to be susceptible and 39 (11.1%) were found to be resistant to ceftazidime-avibactam. Of the CRPA strains, 131 (84.5%) were found to be susceptible and 24 (15.5%) were found to be resistant.&#x0D; Conclusion: Determining the regional susceptibility of carbapenem-resistant strains isolated in our hospital to a new antimicrobial combination such as caz-avi will allow a better understanding of the spread of resistance.

Application of Precision Medicine Concepts in Ambulatory Antibiotic Management of Acute Pyelonephritis.

Acute pyelonephritis (APN) is a relatively common community-acquired infection, particularly in women. The early appropriate antibiotic treatment of this potentially life-threatening infection is associated with improved outcomes. The international management guidelines for complicated urinary tract infections and APN recommend using oral antibiotics with <10% resistance among urinary pathogens. However, increasing antibiotic resistance rates among Escherichia coli and other Enterobacterales to fluoroquinolones, trimethoprim-sulfamethoxazole (TMP-SMX), and beta-lactams has left patients without reliable oral antibiotic treatment options for APN. This narrative review proposes using precision medicine concepts to improve empirical antibiotic therapy for APN in ambulatory settings. Whereas resistance rates to a particular antibiotic class may exceed 10% at the population-based level, the predicted antibiotic resistance rates based on patient-specific risk factors fall under 10% in many patients with APN on the individual level. The utilization of clinical tools for the prediction of fluoroquinolones, TMP-SMX, and third-generation cephalosporin resistance improves the ambulatory antibiotic management of APN. It may also reduce the need to switch antibiotic therapy later based on the in vitro antibiotic susceptibility testing results of bacterial isolates in urinary cultures. This approach may mitigate the burden of increasing antibiotic resistance in the community by ensuring that the initial antibiotic prescribed has the highest likelihood of treating APN appropriately.

The Change in Antimicrobial Resistance During the COVID-19 Pandemic in Türkiye

Antimicrobial resistance (AMR) is one of the most important problems threatening human health worldwide. The impact of the Coronavirus disease-2019 (COVID-19) pandemic on AMR continues to be discussed. Some researchers argue that the pandemic will increase AMR rates, while others suggest the opposite. The aim of this study was to investigate the change in AMR of Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus strains in three cross-sectional periods in Türkiye, the first one before the COVID-19 pandemic, the second and the third one during the pandemic. The change in antibiotic susceptibility in Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus strains isolated from urine, blood, and lower respiratory tract samples of patients hospitalized in intensive care units and wards of hospitals before (November 2019) and during the COVID-19 pandemic (November 2020 and July 2021) was investigated in this study. A total of 17 voluntary hospitals, members of the Antibiotic Susceptibility Surveillance Study Group (ADSI) of the Society for Clinical Microbiology Specialists (KLIMUD), participated in the study. Identification of bacteria was performed with automated bacterial identification systems (VITEK2, bioMérieux, France or Phoenix, BD, USA). Antibiotic susceptibility tests were performed in one center with the Kirby-Bauer disc diffusion method and in other centers with automated antibiotic susceptibility test systems (VITEK2, bioMérieux, France or Phoenix, BD, USA), and the results were evaluated according to European Committee on Antimicrobial Susceptibility Testing (EUCAST) criteria. Antibiotic susceptibility ratios were statistically analyzed using either the chi-square or Fisher's exact test. A p-value of < 0.05 was considered statistically significant. Antibiotic susceptibility test results of a total of 4030 strains; 1152, 1139, and 1739 belonging to November 2019, November 2020, and July 2021, respectively; were examined. While cefotaxime and ceftazidime susceptibility rates in E.coli strains increased during the pandemic period compared to previous period (p= 0.04, p= 0.001, respectively); nitrofurantoin sensitivity (p= 0.02) and extended-spectrum beta-lactamase (ESBL) ratios (p< 0.001) were found to be decreased. It was determined that the susceptibility rates of all other examined antimicrobials did not change statistically. It was observed that the susceptibility rates of all antibiotics in K.pneumoniae isolates decreased during the pandemic period, but the ESBL rates increased between 2019-2020 (p= 0.01) and decreased between 2020-2021 (p= 0.02). It was found that ESBL rates increased before and after the pandemic. It was observed that the susceptibility to ciprofloxacin (p= 0.0001), levofloxacin (p= 0.003), and gentamicin (p= 0.005) in S.aureus strains increased during the pandemic period. No significant changes were observed in other antibiotic susceptibility rates. Methicillin resistance of S.aureus (MRSA) strains decreased between 2019-2020 (p= 0.03) and increased again in 2021 (p= 0.04) and returned to the pre-pandemic rate. Our study results suggest that the measures taken to reduce the spread of COVID-19 with the pandemic (such as quarantine practices, increased hand hygiene, mask use, and national/international travel restriction) may reduce the spread of bacteria such as ESBL-producing E.coli and the rate of MRSA, which is considered as a hand hygiene indicator. The increase in the later stages of the pandemic recalls the relaxation in compliance with hand hygiene rules. The decrease in the susceptibility rate of K.pneumoniae isolates to antibiotics and the increase in the ESBL rate may be due to inappropriate and excessive use of antibiotics during the pandemic period. However, we believe that these data should be supported by studies to be conducted nowadays when all the rules and measures are back as if the pandemic has ended.