High Susceptibility Rates Research Articles

Invasive Mould Infections Following Combat-Related Injuries-A Retrospective Cohort Study.

Available data on combat wound-related invasive mould infections (IMIs) are limited. We aimed to describe the characteristics and outcomes of IMIs in casualties of a recent conflict. A retrospective study including hospitalised patients with combat-related injuries, fulfilling criteria for wound-related IMI based on Trauma Infectious Disease Outcomes Study definitions. Patient and injury characteristics, management and outcomes are described and compared to previous cohorts. Mould isolates and susceptibility testing results, including the novel agent manogepix, are reported. Overall, 31 patients (69 mould isolates) were included-resulting in an IMI incidence rate of 1.9%. Blast was the most common injury mechanism (71%), with limb amputations and abdominoperineal injuries in 35% and 45%, respectively. Mould cultures, obtained mostly from lower extremities wounds (62%), were positive in all patients. Most (68%) had poly-mould infections, with Aspergillus and Fusarium species predominating. Overall, non-susceptibility rates of > 50% to newer azoles and 38% to amphotericin B reflected the high proportion of Fusarium spp., A. terreus and A. flavus, with the lowest azole minimal inhibitory concentrations demonstrated with posaconazole. Manogepix displayed good in-vitro activity against all isolates, except for Mucorales species. Two patients (6.5%) died of disseminated IMIs and 19% required amputations. Patients with Mucorales had poorer outcomes (40% mortality/amputation vs. 19% for non-Mucorales). Combat wound-related IMIs are uncommon but carry significant morbidity and mortality. High susceptibility rates to manogepix were observed. Further studies are needed to evaluate optimal surgical approaches and the role of antifungal susceptibility testing in this setting.

Correlation between carbapenem susceptibility in Pseudomonas aeruginosa and modified antibiotic heterogeneity index: a multicenter observational study using a surveillance platform

Abstract Objective: This study focused on exploring the relationship between antimicrobial use indicators, including the modified antibiotic heterogeneity index (mAHI), and the carbapenem susceptibility in Pseudomonas aeruginosa. Design: Survey-based observational study conducted across multiple facilities. Setting: Public community hospital institutions. Methods: This survey was conducted in 15 community hospitals in Japan. Indicators, such as the defined daily doses (DDDs), days of therapy (DOTs), antibiotic heterogeneity index (AHI), and mAHI, were analyzed for P. aeruginosa carbapenem susceptibility using Spearman’s rank correlation. The predictive accuracies of the AHI and mAHI for carbapenem susceptibility were compared using DeLong’s test for the 2 correlated receiver operating characteristic curves. Results: No significant correlations were observed between DDDs or DOTs and carbapenem susceptibility. However, a significant correlation was observed between carbapenem susceptibility and the mAHI (r = 0.261, P = .02), which also demonstrated a higher predictive accuracy for high susceptibility rates than that of the AHI (area under the curve: 0.75 vs 0.58, p < .01). The optimal mAHI cutoff value for predicting 90% susceptibility was 0.765, with a sensitivity of 67.7% and specificity of 76.5%. Conclusions: The mAHI may be a better predictor of carbapenem susceptibility than other commonly used indicators. This study underscores the utility of the mAHI as an effective indicator of antimicrobial usage patterns for managing carbapenem susceptibility in P. aeruginosa. Incorporating the mAHI into antimicrobial stewardship programs could enhance the effectiveness of antimicrobial interventions across diverse healthcare settings.

Characterization and antimicrobial resistance of Staphylococcus hyicus from swine exudative epidermitis in South Korea

BackgroundStaphylococcus hyicus causes porcine exudative epidermitis, predominantly affecting suckling and weaned piglets. This bacterium produces various exfoliative toxins (ExhA, ExhB, ExhC, ExhD, SHETA, and SHETB), which are responsible for the clinical manifestations of exudative epidermitis. However, treatment failure is common due to frequent antimicrobial resistance in porcine strains. Therefore, this study aimed to identify the genes encoding exfoliative toxins and assess the antimicrobial resistance profiles of S. hyicus. A total of 17 S. hyicus isolates were collected from piglets with skin lesions from 2014 to 2021. All strains were subjected to species-specific polymerase chain reaction targeting sodA to confirm the presence of S. hyicus, and polymerase chain reaction amplification of exfoliative toxin genes (exhA, exhB, exhC, exhD, sheta, and shetb) was performed to differentiate toxigenic strains. Pulsed-field gel electrophoresis analysis and minimum inhibitory concentration tests using broth microdilution were conducted to further analyze the strains.ResultsExfoliative toxin genes were detected in 52.9% (n = 9) of the S. hyicus isolates, with notable detection of exhB (17.6%), exhC (17.6%), exhD (11.8%), exhA (5.9%), sheta (0%), and shetb (0%). Pulsed-field gel electrophoresis analysis categorized the isolates into 11 pulsotypes with 70% similarity. Among 18 tested antimicrobials, all isolates exhibited 100% susceptibility to ceftiofur and sulfonamides and high susceptibility rates to neomycin, tilmicosin, and tetracyclines. Whereas the susceptibility rate of spectinomycin was 0% in all isolates, multidrug resistance was observed in 82.4% of the isolates, and in all toxigenic strains.ConclusionsThese findings provide crucial insights for monitoring and devising effective treatment strategies for managing exudative epidermitis in pigs caused by S. hyicus.

Retrospective analysis of antimicrobial susceptibility profiles of non-diphtheriae Corynebacterium species from a tertiary hospital and reference laboratory, 2012-2023.

A total of 1,925 Corynebacterium isolates were tested for antimicrobial susceptibility at the Mayo Clinic Microbiology laboratory (Rochester, Minnesota) from January 2012 to March 2023, with C. striatum (35.6%) and C. amycolatum (24.4%) identified as the predominant species. Species known to potentially carry diphtheria toxin were excluded. Common sources of isolation included skin and soft tissue (56.8%), bone and/or native joint synovial fluid (14.2%), urine (13.1%), sputum (6.1%), and blood (5.9%). For penicillin, susceptibility decreased from 47.5% (58 of 122) in 2012 to 20.6% (14 of 68) in 2023. Isolates also showed a decrease in susceptibility to erythromycin from 22.4% (26 of 116) in 2012 to 13.2% (9 of 68) in 2023. Susceptibility to trimethoprim-sulfamethoxazole averaged around 50% throughout the period. Notably, linezolid and vancomycin were universally effective in vitro against all species. The highest susceptibility rates among tested oral agents were to linezolid and doxycycline for non-C. striatum species. Daptomycin minimal inhibitory concentrations (MICs) of >256 µg/mL were observed for one C. amycolatum isolate, one C. tuberculostearicum isolate, and for seven C. striatum isolates, all from patients with prior daptomycin exposure. Daptomycin MICs of 2 µg/mL (nonsusceptible) were observed in one C. striatum isolate recovered from a daptomycin-naïve patient and in six C. jeikeium isolates, from both daptomycin-exposed and non-exposed patients. Significant variation in susceptibility profiles across different Corynebacterium species underscores the importance of performing antimicrobial susceptibility testing to guide effective treatment. Moreover, multidrug resistance observed in C. striatum poses substantial therapeutic challenges especially in patients requiring prolonged or chronic antibiotic suppression.

Bacterial isolates and antibiotic sensitivity in canine bacterial keratitis in Korea.

To analyze bacterial isolates associated with canine bacterial keratitis and their antibiotic susceptibility patterns in Korea, focusing on multidrug resistance (MDR) and identifying effective antibiotic combinations for clinical treatment. A total of 146 dogs diagnosed with suspected bacterial keratitis between October 2022 and October 2023 in Korea, with 157 eye samples collected for analysis. Eye samples were cultured to isolate bacteria, and antibiotic susceptibility testing was performed using the minimum inhibitory concentration (MIC) method. Bacterial identification was conducted using Matrix-Assisted Laser Desorption/Ionization Time-of-Flight (MALDI-TOF). The study assessed the efficacy of individual antibiotics and combination therapies. Bacteria were isolated in 55.4% of the samples. The most common genera were Staphylococcus species (48.5%, 48/99), Streptococcus species (13.1%, 13/99), Pseudomonas species (9.1%, 9/99), and Escherichia coli (9.1%, 9/99). Amikacin (84.8%) showed the highest antibiotic susceptibility, while doxycycline exhibited the lowest (17.2%). The most effective antibiotic combinations were amikacin-moxifloxacin (93%). MDR isolates accounted for 52.5% (52/99) of the total bacterial samples. Staphylococcus species were the most common isolates, with 52.5% showing MDR, underscoring the need to curb antibiotic misuse. While antibiotics like amikacin demonstrated high susceptibility rates, their use should be reserved for resistant infections to prevent further resistance development. Rather than focusing solely on finding effective combinations of antibiotics, it is crucial to consider alternative treatment strategies that offer more sustainable solutions. Rather than relying on antibiotic combinations, attention should shift to sustainable alternatives to treat bacterial keratitis and reduce antibiotic dependence in clinical practice.

Comparison of the aetiology, microbiological isolates and antibiotic susceptibilities of endophthalmitis between children and adults in southern China: a retrospective, cohort study

ObjectivesTo compare aetiology, microbiological isolates and antibiotic susceptibilities of endophthalmitis between children and adults.DesignRetrospective observational study.ParticipantsPatients admitted to Zhongshan Ophthalmic Center between January 2013 and December 2019 with clinically diagnosed...

Prevalence of JC polyomavirus among rheumatoid arthritis and systemic lupus erythematosus patients and its correlation with vitamin D levels.

Vitamin D deficiency in viral infection associated with autoimmune diseases is well documented. This study assessed the prevalence of JC virus in patients with rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE), and its correlation with vitamin D level. Serum and urine samples were collected from 50 patients with RA and SLE. DNA was extracted and subjected to PCR test. Positive PCR products were sequenced, phylogenetic tree was constructed to determine the JC virus genotype. The patient's vitamin D level was evaluated. Of 50 patients, 19 (38%) were diagnosed as RA, and 31 (62%) were identified as SLE. JC virus DNA was detected in 17 (34%) patients' urine samples including 5 (26.3%) RA and 12 (38.7%) SLE cases. JC virus DNA was detected 2 (4%) in patients' serum samples (one RA. and one SLE). JC virus genotype 3A was dominant. Interestingly, the SLE patients with positive JC virus showed lowered vitamin D compared to patients with negative JC virus (P<0.005). Given the high rate of JC virus, DNA detection and susceptibility of patients for PML development, it is recommended that detection of JC virus DNA and vitamin D level should be implemented for patients with RA/SLE prior to treatment.

Emergence of lineage ST150 and linezolid resistance in Enterococcus faecalis: a molecular epidemiology study of UTIs in Tehran, Iran.

Urinary tract infections (UTIs) represent one of the most prevalent bacterial infections, with Enterococcus species now recognized as the second leading cause of these infections. This study focused on symptomatic UTI cases to investigate the risk factors associated with Enterococcus faecalis clinical isolates in patients from Tehran, Iran. Urine samples were collected from patients presenting with symptomatic UTIs. The identification of E. faecalis isolates was performed using standard microbiological techniques, with confirmation via polymerase chain reaction (PCR). Antibiotic susceptibility testing was conducted using the Kirby-Bauer disc diffusion method. The presence of virulence genes was determined through PCR, and biofilm formation was assessed using the microtiter plate method. Additionally, multi-locus sequence typing (MLST) was utilized to genotype linezolid-resistant isolates. Out of 300 UTI cases, E. faecalis was identified as the causative agent in 160 instances. Notably, a high proportion of these isolates exhibited resistance to tetracycline (83.8%) and minocycline (82.5%). Linezolid resistance was observed in 1.3% (n = 2) of the isolates. Conversely, the highest susceptibility rates were observed for vancomycin, penicillin G, ampicillin, and nitrofurantoin, each demonstrating a 98.8% susceptibility rate. Biofilm formation was detected in 25% of the E. faecalis isolates. A significant majority (93.8%) of the isolates harbored the efbA and ace genes, with varying frequencies of esp (72.5%), asa1 (61.2%), cylA (52.5%), and gelE (88.8%) genes. MLST analysis demonstrated that both linezolid-resistant isolates, characterized by strong biofilm formation and the presence of virulence genes, were assigned to the ST150 lineage, which has not been previously documented in clinical settings. The emergence of the ST150 clonal lineage, underscores its clinical significance, particularly in relation to linezolid resistance in E. faecalis. This study adds to the growing body of evidence linking specific clonal lineages with antibiotic resistance, highlighting the critical need for ongoing surveillance and molecular characterization of resistant pathogens.

Phenotypic antimicrobial resistance associated with different &lt;em&gt;bla&lt;/em&gt; genotypes and their combinations in Enterobacterales

Introduction: Varying combinations of β-lactamase genes (bla) in Enterobacterales manifest different resistant phenotypes.Objectives: This study aimed to identify bla gene types and combinations resulting in variations in phenotypic antimicrobial resistance.Methods: Minimum inhibitory concentrations (MICs) of 75 extended spectrum β-lactamase (ESBL), AmpC β-lactamase and carbapenemase-producing Entero-bacterales isolates from a variety of clinical specimens were determined by Vitek micro-broth dilution. Bla genes were detected by 16-plex tandem PCR panel and Xpert Carba-R assay. BlaCTX-M group-1 and blaOXA-48 were the most common ESBL and carbapenemase genes, respectively.Results: Majority of the isolates (92%, 69/75) had bla gene combinations. Thirty-eight isolates (51%) carried ESBL, AmpC genes and/or narrow spectrum bla genes without any carbapenemase genes. The common bla gene combination in these isolates was blaCTX-M group-1 + blaOXA1 which is known to confer decreased susce-ptibility to piperacillin-tazobactam. Antibiotics with potential activity against ESBL-producing bacteria such as fourth generation cephalosporins, β-lactam/β-lactam-inhibitor combinations, quinolones and gentamicin also showed low rates of susceptibility. Highest susceptibility rates were to meropenem (92%) and amikacin (92%). Thirty-seven isolates (49%) carried carbapenemase genes as well. These isolates showed even higher resistance rates to all antibiotics, except amikacin (92%susceptible). Significantly higher MIC values for cefoxitin, ceftazidime, ceftriaxone, cefepime, meropenem, amikacin, tobramycin and trimethoprim-sulfamethoxazole were seen in isolates carrying blaNDM than blaOXA-48. However, a higher MIC for norfloxacin was seen in isolates with blaOXA-48.Conclusions: In conclusion, this study showed that Enterobacterales with different bla gene combinations manifest variations in phenotypic resistance to both β-lactam and non-β-lactam antibiotics.

Polymyxin resistance in Enterobacter cloacae complex in Brazil: phenotypic and molecular characterization.

Enterobacter cloacae complex isolates have been reported as an important nosocomial multidrug resistance pathogen. In the present study, we investigated antimicrobial susceptibility and the colistin-resistance rates,their genetic determinants and clonality among clinical E. cloacae complex isolates from different Brazilian states. For this, an initial screening was carried out on 94 clinical isolates of E. clocacae complex received between 2016 and 2018 by LAPIH-FIOCRUZ, using EMB plates containing 4μg/mL of colistin, followed MIC determination, resulting in the selection of 26 colistin-resistant isolates from the complex. The presence of carbapenemases encoding genes (blaKPC, blaNDM and blaOXA-48), plasmidial genes for resistance to polymyxins (mcr1-9) and mutations in chromosomal genes (pmrA, pmrB, phoP and phoQ) described as associated with resistance to polymyxin were screened by PCR and DNA sequencing. Finally, the hsp60 gene was sequenced to identify species of the E. cloacae complex and genetic diversity was evaluated by PFGE and MLST. The results have shown that among 94 E. cloacae complex isolates, 19 (20.2%) were colistin-resistant. The resistant strains exhibited MIC ranging from 4 to 128µg / mL and E. hormaechei subsp. steigerwaltii was the prevalent species in the complex (31,6%), followed by E. cloacae subsp. cloacae (26,3%). The antimicrobials with the highest susceptibility rate were gentamicin (21%) and tigecycline (26%). Carbapenemases encoding genes (blaKPC n = 5, blaNDM n = 1) were detected in 6 isolates and mcr-9 in one. Among the modifications found in PmrA, PmrB, PhoP e PhoQ (two-component regulatory system), only the S175I substitution in PmrB found in E. cloacae subsp cloacae isolates were considered deleterious (according to the prediction of PROVEAN). By PFGE, 13 profiles were found among E. cloacae complex isolates, with EcD the most frequent. Furthermore, by MLST 10 ST's, and 1 new ST, were identified in E. cloacae. In conclusion, no prevalence of clones or association among carbapenemase production and polymyxin resistance was found between the E. cloacae. Thereby, the results suggest that the increased polymyxin-resistance is related to the selective pressure exerted by the indiscriminate use in hospitals. Lastly, this study highlights the urgent need to elucidate the mechanism involved in the resistance to polymyxin in the E. cloacae complex and the development of measures to control and prevent infections caused by these multiresistant bacteria.

Dynamic cytokine profiles of bloodstream infection caused by Klebsiella pneumoniae in China

ObjectivesThe aim of this work was to assess dynamic cytokine profiles associated with bloodstream infection (BSI) caused by Klebsiella pneumoniae (Kpn) and investigate the clinical features associated with mortality.MethodsA total of 114 patients with positive BSI-Kpn and 12 sepsis individuals without blood positive bacteria culture were followed up. Cytokine profiles were analyzed by multiplex immunoassay on the first, third, seventh and fourteenth day after diagnosis. The test cytokines included arginase, interferon-gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), interleukin (IL)-1β, IL-4, IL-6, IL-10, IL-12 (p70), and IL-23. The minimum inhibitory concentration (MIC) of 24 antibiotics were tested for BSI-Kpn. Risk factors associated with the 30-day mortality and 120-day mortality were evaluated using logistic analyses and nomogram.ResultsThere were 55 out of 114 patients with BSI-Kpn were included. All isolates showed high susceptibility rate to novel avibactam combinations. The level of arginase was the highest in carbapenem-resistant Kpn (CRKP) patients. The AUCs of arginase, TNF-α and IL-4 reached 0.726, 0.495, and 0.549, respectively, whereas the AUC for the combination of these three cytokines was 0.805. Notably, 120-day mortality in patients with CRKP was higher than carbapenem-sensitive K. pneumoniae (CSKP). Furthermore, the long-term and high levels of IL-6 and IL-10 were associated with death.ConclusionsHigh expression of arginase is correlated with CRKP. In addition, BSI-CRKP could result in indolent clinic course but poor long-term prognosis. Continuous increase of IL-6 and IL-10 were associated with mortality.

Creation of a Multi-Year Pediatric Candidemia Antibiogram in Georgia Identifies Changing Epidemiology and Resistance Trends

Background: Invasive candidiasis, including candidemia, is a significant cause of morbidity and mortality in medically complex and immunocompromised children. Understanding the epidemiology and antifungal susceptibility patterns of Candida infections could help guide empiric antifungal therapy. Methods: This fungal antibiogram was created at a large quaternary children’s health system in Georgia. Blood isolates positive for Candida spp. from 2019 through 2023 were included. The number and percentage of isolates for each Candida spp was recorded by year and then as the combined 5-year total. The Clinical and Laboratory Standards Institute (CLSI) antifungal interpretative criteria were used, and we only included one unique Candida spp isolate per patient. Due to the limited number of isolates, the combined 5 years of isolates were used to create the fungal antibiogram. Data are shown as percent susceptible using CLSI interpretative criteria and number of isolates. Results: Between 2019 and 2023 there were 124 unique blood isolates of Candida spp identified. The most common isolates were C. albicans (33%), C. parapsilosis (27%), C. glabrata (14%) and C. tropicalis (11%). Over the 5 years of the study, the percentage of C. albicans isolates decreased from 47% to 21%. The change in epidemiology was not driven by a single Candida species but varied from year to year. For C. albicans, susceptibility was 100% for fluconazole and micafungin. For C. parapsilosis, susceptibility to fluconazole and micafungin was 97% and 94%, respectively. Fluconazole susceptibility was lowest for C. glabrata (88%) and C. krusei (0%). Using CLSI epidemiological cutoff values (ECV) to evaluate the amphotericin B results, none of the isolates had results greater than the CLSI ECVs. Comparing 2019 and 2023, the percentage of Candida blood isolates resistant to fluconazole increased from 5% to 18.5%. Conclusion: C. albicans was the most frequently identified cause of candidemia in children, but there was a gradual increase in fungemia caused by other Candida spp. over the past 5 years including Candida with fluconazole resistance. Overall, our findings demonstrate high susceptibility rates to fluconazole and echinocandins in Candida spp. blood isolates. Further research is needed to identify risk factors for antifungal resistant candidemia in pediatric patients.Disclosure: Mark Gonzalez: Honoria for a one time consulation with NaviDx consulting in May of 2022. Honoria from the American Society for Microbiology for writing of a chapter in the Clinical Microbiology Procedures Handbook.

Susceptibility evaluation of novel beta-lactam/beta-lactamase inhibitor combinations against carbapenem-resistant Klebsiella pneumoniae from bloodstream infections in hospitalized patients in Brazil

IntroductionNovel beta-lactam/beta-lactamase inhibitor (BIBLI) combinations are commercially available and have been used for treating carbapenem-resistant Klebsiella pneumoniae (CRKP) infections. Continuous surveillance of susceptibility profiles and resistance mechanism identification are necessary to monitor the evolution of resistance within these agents. ObjectiveThe purpose of this study was to evaluate the susceptibility rates of ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam in CRKP isolated from patients with bloodstream infections who underwent screening for a randomized clinical trial in Brazil. MethodsMinimum inhibitory concentrations (MICs) were determined for meropenem, ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam using the gradient diffusion strip method. Carbapenemase genes were detected by multiplex real-time polymerase chain reaction. Klebsiella pneumoniae carbapenemase (KPC)-producing isolates showing resistance to any BLBLI and New Delhi Metallo-beta-lactamase (NDM)-producing isolates with susceptibility to any BLBLI isolates were further submitted for whole-genome sequencing. ResultsFrom a total of 69 CRKP isolates, 39 were positive for blaKPC, 19 for blaNDM and 11 for blaKPC and blaNDM. KPC-producing isolates demonstrated susceptibility rates above 94 % for all BLBLIs. Two isolates with resistance to meropenem/vaborbactam demonstrated a Gly and Asp duplication at the porin OmpK36 as well as a truncated OmpK35. All NDM-producing isolates, including KPC and NDM coproducers, demonstrated susceptibility rates to ceftazidime/avibactam, imipenem/relebactam and meropenem/vaborbactam of 0 %, 9.1–21.1 % and 9.1–26.3 %, respectively. Five NDM-producing isolates that presented susceptibility to BLBLIs also had porin alterations ConclusionsThis study showed that, although high susceptibility rates to BLBLIs were found, KPC-2 isolates were able to demonstrate resistance probably as a result of porin mutations. Additionally, NDM-1 isolates showed susceptibility to BLBLIs in vitro.

A Comparison Study between Raw and Dried Milk Powder in Antimicrobial Susceptibility Pattern of Staphylococcus aureus.

Milk is a rich source of nutrients that basically required by different neonatal species. At the same time; it can become microbial hazard to users when the principles of hygiene and purification are inferior. The purpose of the study was to explain the prevalence and the contamination rate of Staphylococcus aureus in raw and dried milk powder, differentiation of Methicillin Resistant Staphylococcus aureus (MRSA) from Methicillin Sensitive Staphylococcus aureus (MSSA) in Al- Muthanna Province; additionally profile of resistance for antibiotics. A total of forty milk samples were collected (during March 2021 to January 2022), included twenty samples of buffalo raw milk were obtained aseptically from the farms and kept in a sterile tubes which were directly transported into laboratory; whereas twenty dried milk powder samples were obtained from the local markets. The MRSA isolates were screened for susceptibility profile. The results clarified a significant difference between buffalo raw milk and dried milk powder at P-value &lt; 0.05. Regarding to antimicrobial resistance the results confirmed vast majority of MRSA isolates from raw milk resistance for most antimicrobial especially Methicillin and Oxacillin percentage up 100% , while the resistance percentage up to (66.67%) and (33.33%) for Erythromycin and Amoxicillin respectively. Whereas, the highest rate of susceptibility was recorded in Rifampin antimicrobial which have effect on MRSA isolate reach to (100%). The study concluded the proper sanitary procedures, such as storage, handling, and transportation, are required to decrease the presence of S. aureus and MRSA in milk and their resistance to the majority of antibiotics.

Review of the In Vitro Microbiological Activity of Mecillinam Against Common Uropathogens in Uncomplicated Urinary Tract Infection: Focus on Resistant Pathogens.

Antimicrobial resistance in uropathogens commonly causing urinary tract infections (UTIs) is a growing problem internationally. Pivmecillinam, the oral prodrug of mecillinam, has been used for over 40 years, primarily in Northern Europe and Canada. It is recommended in several countries as a first-line agent for the treatment of uncomplicated UTIs (uUTIs) and is now approved in the United States. We performed a structured literature search to review the available evidence on susceptibility of common uUTI-causing uropathogens to mecillinam. Among 38 studies included in this literature review, susceptibility rates for Escherichia coli to mecillinam-including resistant phenotypes such as extended-spectrum β-lactamase-producing E. coli-exceed 90% in most studies. High rates of susceptibility were also reported among many other uropathogens including Klebsiella spp., Enterobacter spp., and Citrobacter spp. In the current prescribing climate within the United States, pivmecillinam represents a viable first-line treatment option for patients with uUTI.

Environmental Aerobic Bacterial Associated with Infectious and General Solid Waste: Screening at the “Université des Montagnes” Teaching Hospital Waste Accumulation Sites

Background: Waste is a source of potentially dangerous microorganisms for users of healthcare facilities, and its accumulation is a risk factor for infectious agent dissemination. Objective: The first aim of the present study was to identify and quantify aerobic bacteria around solid waste accumulation sites at the “Université des Montagnes” Teaching Hospital. The second one was to assess bacteria susceptibility to common conventional antibacterial agents. Methods: Soil samples and airborne bacteria were collected at various distances from the target solid waste accumulation sites. Bacteria isolation and susceptibility tests were thereafter conducted according to standard protocols. Results: Isolated organisms (123 bacterial isolates) included Staphylococcus spp (48%), Gram-positive rods (32%) and Gram-negative rods (20%). Polymorphism and bacterial loads were highest at the sampling locations closer to the accumulation sites and decreased with increasing distances from these sites. Overall findings revealed that variations of polymorphism and bacterial loads is likely associated with anthropogenic activities. In addition, susceptibility rates for Staphylococcus were high. Conclusion: Together with the overall bacterial population distribution trends, the high susceptibility rates recorded deserve better understanding in future research initiatives for optimal hospital hygiene.

Risk factors for bacteremic pneumonia and mortality (28-day mortality) in patients with Acinetobacter baumannii bacteremia

BackgroundPatients infected with Acinetobacter baumannii (AB) bacteremia in hospital have high morbidity and mortality. We analyzed the clinical characteristics of pneumonia and nonpneumonia-related AB bloodstream infections (AB BSIs) and explored the possible independent risk factors for the incidence and prognosis of pneumonia-related AB BSIs.MethodsA retrospective monocentric observational study was performed. All 117 episodes of hospital-acquired AB bacteremia sorted into groups of pneumonia-related AB BSIs (n = 45) and nonpneumonia-related AB BSIs (n = 72) were eligible. Univariate/multivariate logistic regression analysis was used to explore the independent risk factors. The primary outcome was the antibiotic susceptibility in vitro of pneumonia-related AB BSIs group. The secondary outcome was the independent risk factor for the pneumonia-related AB BSIs group.ResultsAmong 117 patients with AB BSIs, the pneumonia-related group had a greater risk of multidrug resistant A. baumannii (MDRAB) infection (84.44%) and carbapenem-resistant A. baumannii (CRAB) infection (80%). Polymyxin, minocycline and amikacin had relatively high susceptibility rates (> 80%) in the nonpneumonia-related group. However, in the pneumonia-related group, only polymyxin had a drug susceptibility rate of over 80%. Univariate analysis showed that survival time (day), CRAB, MDRAB, length of hospital stay prior to culture, length of ICU stay prior to culture, immunocompromised status, antibiotics used prior to culture (n > = 3 types), endotracheal tube, fiberoptic bronchoscopy, PITT, SOFA and invasive interventions (n > = 3 types) were associated with pneumonia-related AB bacteremia. The multivariate logistic regression analysis revealed that recent surgery (within 1 mo) [P = 0.043; 0.306 (0.098–0.962)] and invasive interventions (n > = 3 types) [P = 0.021; 0.072 (0.008–0.671)] were independent risk factors related to pneumonia-related AB bacteremia. Multivariate logistic regression analysis revealed that length of ICU stay prior to culture [P = 0.009; 0.959 (0.930–0.990)] and recent surgery (within 1 mo) [P = 0.004; 0.260 (0.105–0.646)] were independent risk factors for mortality in patients with pneumonia-related AB bacteremia. The Kaplan‒Meier curve and the timing test showed that patients with pneumonia-related AB bacteremia had shorter survival time compared to those with nonpneumonia-related AB bacteremia.ConclusionsOur study found that A. baumannii had a high rate of antibiotic resistance in vitro in the pneumonia-related bacteremia group, and was only sensitive to polymyxin. Recent surgery was a significantly independent predictor in patients with pneumonia-related AB bacteremia.

Antimicrobial resistance of genitalmycoplasmas recovered from nonpregnant women in Greece: trends over the last 15years.

Aim: To study antimicrobial susceptibilities of genital mycoplasmas recovered from endocervical samples of reproductive-age, nonpregnant women (n =8,336). Materials & methods: For isolation and susceptibility testing, the Mycoplasma IST2 kit was used. Results: As many as 2093 samples were positive for mycoplasmas. The vast majority (>96%) of Ureaplasma urealyticum remained susceptible to tetracycline, doxycycline, josamycin and pristinamycin, whereas susceptibility rates to azithromycin and fluoroquinolones were significantly decreased. Mycoplasma hominis exhibited high susceptibility rates to doxycycline, pristinamycin and josamycin (98.1-100%), while susceptibilities to tetracycline and fluoroquinolones were considerably lower. Conclusion: Doxycycline remained highly potent for treating mycoplasmas; nevertheless, susceptibilities to other antimicrobials were significantly diminished.

Microbiological and Antimicrobial Susceptibility Pattern of Asymptomatic Bacteriuria in Pregnant Women Attending SQUH.

Our research aimed to study the microbiology and antimicrobial resistance in asymptomatic bacteriuria (ASB) among Omani pregnant women. We conducted a retrospective study that included data from 196 Omani pregnant women with ASB who received care at Sultan Qaboos University Hospital from 2010-2019. Data were obtained from the patients' electronic medical records including demographics, clinical details, isolated organisms, antimicrobial susceptibility results, and prescribed antibiotics. ASB was detected in 56.1% of cases during the third trimester. Klebsiella pneumoniae(32.1%) was the most frequently isolated organism, followed by Escherichia coli (29.6%). Twenty-one (10.7%) isolates were extended-spectrum beta-lactamase (ESBL)-producing organisms. The overall microbiological susceptibility pattern showed that organisms have a high susceptibility rate to nitrofurantoin reaching 82.8%, followed to a lesser extent by cefuroxime and augmentin. The susceptibility of E. coli and K. pneumoniae to cefuroxime was 74.1% and 71.4%, respectively. Only 52.4% of all isolated ESBL-producing organisms were susceptible to nitrofurantoin. K. pneumoniae and E. coli were the most frequently isolated bacteria in ASB, representing 60.7% of total isolates. A high prevalence of ESBL-producing organisms, 10.7% of the total isolates, was observed. Cefuroxime is an appropriate empirical antibacterial therapy for ASB and urinary tract infection in pregnant women. Nitrofurantoin should be considered for empirical antibiotic therapy in settings of high prevalence of ESBL-producing organisms.

Multidrug resistant profiles of clinical isolates of Escherichia coli, Salmonella typhi and Shigella species

In order to determine the antibiotic susceptibility pattern and multi antibiotic resistance index of E.coli, Salmonella typhi and Shigella species, a total of 32 pre-identified clinical isolates were obtained and subjected to conventional biochemical and gram staining reaction for confirmation. Antibiotic susceptibility testing to ten commonly prescribed antibiotics (Amplicin (PN:30 mcg), Gentamicin (GEN:10 mcg), Streptomycin (STR:30 mcg), Septrin (SXT:30 mcg), Nalidixic acid (NAL:30 mcg), Ciprofloxacin (CIP:10 mcg), Augmentin (AU:30 mcg), Reflacin (PEF:10 mcg), Tarivid (OFX:10mcg), and Ceporexin (CEP:10 mcg) was considered using disc agar diffusion method and reported with the Clinical and Laboratory Standard Institute Interpretative chart. Zones of inhibition were measured and Multiple Antibiotic Resistance index was calculated. Salmonella isolates demonstrated a high rate of susceptibility to Tarivid (90%), Reflaxin (90%), Gentamycin (80%), ciprofloxacin (60%), Augmentin (80%) and moderately susceptible to Streptomycin (40%) and Septrin (20%) with high resistance to Nalidixic acid (90%), Amplicin (90%) and Ceporexin (70%). Nearly all Shigella isolates were susceptible to Augmentin (80%), Reflaxin (90%), Tarivid (80%), intermediate susceptibility was also noted in Streptomycin (40%) and Ceporexin (50%) while high resistance to ciprofloxacin (80%), Amplicin (90%), Septrin (70%) and Nalidixi acid (90%). High rate of resistance was observed to nearly five antibiotics in E,coli with low susceptibility rate to all the antibiotics tested. All the isolates had Multiple Antibiotic Resistance index greater than 0.2 and above. This may be as a result of previous exposure to antibiotics and development of resistance to commonly prescribed antibiotics, hence, antimicrobial susceptibility testing is imperative in selecting therapeutic options.