-
The Journal of Antimicrobial... Jul 2024Successful use of carbapenems in combination with cefazolin or oxacillin for treatment of MSSA bacteraemia has been described; however, comparative data to standard...
BACKGROUND
Successful use of carbapenems in combination with cefazolin or oxacillin for treatment of MSSA bacteraemia has been described; however, comparative data to standard treatment approaches are lacking.
METHODS
This was a multicentre, retrospective study of adult patients with MSSA bacteraemia for >48 h. Standard treatment was considered monotherapy with cefazolin, oxacillin or nafcillin. Combination therapy was defined as the addition of ertapenem or meropenem to standard treatment for at least 24 h. The primary outcome was duration of bacteraemia defined as time from administration of an antibiotic with in vitro activity to first negative blood culture. Time to blood culture sterilization was compared through risk-set matching with aid of a propensity score.
RESULTS
Overall, 238 patients were included; 66% (157/238) received standard treatment and 34% (81/238) received combination therapy. The median (IQR) time to carbapenem initiation was 4.7 (3.63-6.5) days. Patients who received combination therapy were younger (P = 0.012), more likely to have endocarditis (P = 0.034) and had longer median duration of bacteraemia (P < 0.001). After applying risk-set matching, patients who received combination therapy experienced faster time to blood culture sterilization compared with control patients [HR = 1.618 (95% CI; 1.119-2.339) P = 0.011]. Using a paired hazard model, 90 day mortality rates were not statistically different among patients who received combination therapy versus matched controls [HR = 1.267 (95% CI; 0.610-2.678), P = 0.608].
DISCUSSION
Carbapenem combination therapy resulted in faster time to blood culture sterilization, but no differences in overall mortality rates. Randomized trials are critical to determine the utility of carbapenem combination therapy.
PubMed: 38946294
DOI: 10.1093/jac/dkae198 -
In Vivo (Athens, Greece) 2024Bloodstream infections in patients with COVID-19 are linked to higher mortality rates, whilst data on epidemiology and resistance patterns remains scarce to guide...
BACKGROUND/AIM
Bloodstream infections in patients with COVID-19 are linked to higher mortality rates, whilst data on epidemiology and resistance patterns remains scarce to guide management and prevent antibiotic resistance. This research focuses on the prevalence, clinical features, causative microorganisms, and antimicrobial susceptibility of bacterial and fungal secondary bloodstream co-infections in hospitalized patients with COVID-19.
PATIENTS AND METHODS
In this retrospective study analysis of 230 patients with COVID-19 from Central Taiwan (June 2021 to June 2022), pathogens were identified via MALDI-TOF MS and Vitek 2 system with Clinical & Laboratory Standards Institute (CLSI) standards.
RESULTS
In the cohort, 17.8% experienced bloodstream infections, resulting in a total of 45 isolates from the 41 bloodstream infection patients: predominantly gram-positive bacteria (Staphylococcus and Enterococcus) at 69%, gram-negative at 29% (Escherichia coli and Klebsiella pneumoniae), and fungi at 2%. Infected patients showed significantly elevated levels of white blood count (WBC), C-reactive protein (CRP) and procalcitonin (PCT). Of note, resistance to common antibiotics, such as fluoroquinolones, cephalosporins, and oxacillin was significant, especially in K. pneumoniae, Acinetobacter species, and S. aureus infections.
CONCLUSION
Our study highlights the influence of bacterial infections in hospitalized patients with COVID-19. The bacterial infections were discovered to impact the clinical trajectory of COVID-19, potentially exacerbating or mitigating its symptoms, severity and fatality. These insights are pivotal to addressing clinical challenges in COVID-19 management and underscoring the need for tailored medical interventions. Understanding these co-infections is thus essential for optimizing patient care and improving overall outcomes in the post COVID-19 pandemic era.
Topics: Humans; COVID-19; Retrospective Studies; Coinfection; Male; Female; Aged; Middle Aged; SARS-CoV-2; Anti-Bacterial Agents; Taiwan; Hospitalization; Bacteremia; Aged, 80 and over; Adult; Microbial Sensitivity Tests; Drug Resistance, Bacterial
PubMed: 38936952
DOI: 10.21873/invivo.13653 -
Antibiotics (Basel, Switzerland) Jun 2024The -independent oxacillin non-susceptible (MIONSA) strains represent a great clinical challenge, as they are not easily detected and can lead to treatment failure....
Genetic and Phenotypic Changes Related to the Development of -Independent Oxacillin Non-Susceptibility in ST8 Recovered after Antibiotic Therapy in a Patient with Bacteremia.
The -independent oxacillin non-susceptible (MIONSA) strains represent a great clinical challenge, as they are not easily detected and can lead to treatment failure. However, the responsible molecular mechanisms are still very little understood. Here, we studied four clinical ST8-MSSA- isolates recovered during the course of antibiotic treatment from a patient suffering successive episodes of bacteremia. The first isolates (SAMS1, SAMS2, and SAMS3) were susceptible to cefoxitin and oxacillin. The last one (SA2) was susceptible to cefoxitin, resistant to oxacillin, lacked genes, and had reduced susceptibility to teicoplanin. SA2 showed higher β-lactamase activity than SAMS1. However, β-lactamase hyperproduction could not be linked to oxacillin resistance as it was not inhibited by clavulanic acid, and no genetic changes that could account for its hyperproduction were found. Importantly, we hereby report the in vivo acquisition and coexistence of different adaptive mutations in genes associated with peptidoglycan synthesis (, , , , and /), which is possibly related with the development of oxacillin resistance and reduced susceptibility to teicoplanin in SA2. Using three-dimensional models and PBP binding assays, we demonstrated the high contribution of the SA2 PBP2 Ala450Asp mutation to the observed oxacillin resistance phenotype. Our results should be considered as a warning for physicians and microbiologists in the region, as MIONSA detection and treatment represent an important clinical challenge.
PubMed: 38927220
DOI: 10.3390/antibiotics13060554 -
Antibiotics (Basel, Switzerland) Jun 2024, along with various other pathogenic bacteria, may show resistance against a broad spectrum of antibiotics. Evaluating the extent of resistance in harmful...
, along with various other pathogenic bacteria, may show resistance against a broad spectrum of antibiotics. Evaluating the extent of resistance in harmful microorganisms like holds significant importance in crafting novel therapeutic strategies to mitigate or combat the rise of infections stemming from antibiotic-resistant bacteria. The present work aims to investigate the occurrence of antimicrobial resistance among strains in meat products (n = 173), seafood (n = 54), dairy products (n = 19), sauces (n = 2), confectionary products (n = 1), ready-to-eat rice dishes (n = 1), and food-processing environments (n = 19). A total of 269 strains belonging to eight different serovars were tested against 10 antimicrobials. In the classes of antibiotics, most of the strains were resistant antibiotics belonging to the family of β-lactams (92.94%). High proportions of isolates were resistant to oxacillin (88.48%), followed by fosfomycin (85.87%) and flumenique (78.44%). The lowest level of resistance was observed against gentamycin (1.49%). A total of 235 strains (n = 87.36%) showed a profile of multidrug resistance. In conclusion, a high occurrence of resistant and multidrug-resistant strains of was observed among the examined serotypes isolated from different food sources. This understanding enables the adoption of suitable measures to avert contamination and the spread of resistant bacteria via food.
PubMed: 38927191
DOI: 10.3390/antibiotics13060525 -
Microbiology Spectrum Jun 2024Methicillin-resistant (MRSA) bacteremia is a serious clinical challenge with high mortality rates. Antibiotic combination therapy is currently used in cases of...
Methicillin-resistant (MRSA) bacteremia is a serious clinical challenge with high mortality rates. Antibiotic combination therapy is currently used in cases of persistent infection; however, the limited development of new antibiotics will likely increase the need for combination therapy, and better methods are needed for identifying effective combinations for treating persistent bacteremia. To identify pairwise combinations with the most consistent potential for benefit compared to monotherapy with a primary anti-MRSA agent, we conducted a systematic study with an high-throughput methodology. We tested daptomycin and vancomycin each in combination with gentamicin, rifampicin, cefazolin, and oxacillin, and ceftaroline with daptomycin, gentamicin, and rifampicin. Combining cefazolin with daptomycin lowered the daptomycin concentration required to reach 95% growth inhibition (IC) for all isolates tested and lowered daptomycin IC below the sensitivity breakpoint for five out of six isolates that had daptomycin minimum inhibitory concentrations at or above the sensitivity breakpoint. Similarly, vancomycin ICs were decreased when vancomycin was combined with cefazolin for 86.7% of the isolates tested. This was a higher percentage than was achieved by adding any other secondary antibiotic to vancomycin. Adding rifampicin to daptomycin or vancomycin did not always reduce ICs and failed to produce synergistic interaction in any of the isolates tested; the addition of rifampicin to ceftaroline was frequently synergistic and always lowered the amount of ceftaroline required to reach the IC. These analyses rationalize further evaluation of three drug pairs for MRSA bacteremia: daptomycin+cefazolin, vancomycin+cefazolin, and ceftaroline+rifampicin.IMPORTANCEBloodstream infections caused by methicillin-resistant (MRSA) have a high mortality rate despite the availability of vancomycin, daptomycin, and newer antibiotics including ceftaroline. With the slow output of the antibiotic pipeline and the serious clinical challenge posed by persistent MRSA infections, better strategies for utilizing combination therapy are becoming increasingly necessary. We demonstrated the value of a systematic high-throughput approach, adapted from prior work testing antibiotic combinations against tuberculosis and other mycobacteria, by using this approach to test antibiotic pairs against a panel of MRSA isolates with diverse patterns of antibiotic susceptibility. We identified three antibiotic pairs-daptomycin+cefazolin, vancomycin+cefazolin, and ceftaroline+rifampicin-where the addition of the second antibiotic improved the potency of the first antibiotic across all or most isolates tested. Our results indicate that these pairs warrant further evaluation in the clinical setting.
PubMed: 38916355
DOI: 10.1128/spectrum.00976-24 -
International Journal of Food... Jun 2024Pre-cut fresh fruits and vegetables are highly appealing to consumers for their convenience, however, as they are highly susceptible to microbial contamination in...
Pre-cut fresh fruits and vegetables are highly appealing to consumers for their convenience, however, as they are highly susceptible to microbial contamination in processing, the potential risks of foodborne illnesses to public health are not negligible. This study aimed to assess the prevalence, antibiotic susceptibility and molecular characteristics of major foodborne pathogens (Listeria monocytogenes, Escherichia coli, Staphylococcus aureus and Salmonella) isolated from fresh-cut fruits and vegetables in Beijing, China. 86 stains were isolated from 326 samples, with S. aureus being the highest prevalence (15.38 %), followed by E. coli (9.23 %) and L. monocytogenes (1.85 %), while no Salmonella was detected. The prevalence by type of food indicated that fruit trays and mixed vegetables were more susceptible to contamination by pathogens. 98 % of S. aureus were resistant to at least of one antibiotic, and showed a high resistance rate to benzylpenicillin (90 %) and oxacillin (48 %). Among 25 E. coli isolates, 57.67 % of which exhibited multi-drug resistance, with common resist to trimethoprim/sulfamethoxazole (66.67 %) and ampicillin (63.33 %). A total of 9 sequence types (STs) and 8 spa types were identified in 35 S. aureus isolates, with ST398-t34 being the predominant type (42.86 %). Additionally, analysis of 25 E. coli isolates demonstrated significant heterogeneity, characterized by 22 serotypes and 18 STs. Genomic analysis revealed that 5 and 44 distinct antibiotic resistance genes (ARGs) in S. aureus and E. coli, respectively. Seven quinolone resistance-determining regions (QRDRs) mutations were identified in E. coli isolates, of which GyrA (S83L) was the most frequently detected. All the S. aureus and E. coli isolates harbored virulence genes. ARGs in S. aureus and E. coli showed a significant positive correlation with plasmids. Furthermore, one L. monocytogenes isolate, which was ST101 and serogroupIIc from watermelon sample, harbored virulence genes (inlA and inlB) and LIPI-1 pathogenic islands (prfA, plcA, hly and actA), which posed potential risks for consumer's health. This study focused on the potential microbial risk of fresh-cut fruits and vegetables associated with foodborne diseases, improving the scientific understanding towards risk assessment related to ready-to-eat foods.
PubMed: 38905809
DOI: 10.1016/j.ijfoodmicro.2024.110804 -
Enfermedades Infecciosas Y... Jun 2024This study aimed to present real-life data on the use, efficacy, and safety of administering antibiotic therapy through portable elastomeric pumps (pEP) in the...
Outpatient parenteral antibiotic therapy (OPAT) through elastomeric continuous infusion pumps in a real-life observational study: Characteristics, safety, and efficacy analysis.
INTRODUCTION
This study aimed to present real-life data on the use, efficacy, and safety of administering antibiotic therapy through portable elastomeric pumps (pEP) in the outpatient setting.
METHODS
This retrospective observational cohort study was conducted from January 2020 to May 2023 in a large academic hospital in Rome, Italy. All patients receiving antibiotic therapy via pEP were included up to a follow-up period of 90 days after the end of antibiotic therapy. The primary outcome was the treatment response. Secondary endpoints were adverse events attributable to the drug administered, the vascular catheter, or the infection itself.
RESULTS
Of the 490 patients referred to our outpatient parenteral antibiotic therapy (OPAT) unit, 94 (19.2%) received antibiotic therapy via pEP and were included in the final analysis. The most frequently treated infections were those involving bone and prosthetics, including spondylodiscitis (n=27; 28.8%). Most infections were due to Pseudomonas aeruginosa (n=55; 48.3%). Cefepime (n=32; 34.0%), piperacillin/tazobactam (n=29; 30.9%), ceftolozane/tazobactam (n=7; 7.5%), and oxacillin (n=7; 7.5%) were the most frequently administered antibiotics. The infection cure rate reached 88.3% (n=83). 12 patients (12.8%) reported adverse events, of which half (6.4%) were drug-related and half (6.4%) were line-related.
CONCLUSIONS
OPAT through portable elastomeric infusion pumps proved to be safe and effective. It also contributed to the reduction of healthcare costs, fully respecting the principles of personalized medicine. This strategy has emerged as a promising tool for antibiotic stewardship and infection control.
PubMed: 38902156
DOI: 10.1016/j.eimce.2024.04.007 -
Brazilian Journal of Microbiology :... Jun 2024Staphylococcus aureus are extremely important microorganisms, either from an epidemiological point of view or as a pathogen, responsible for causing a series of...
Phenotypic and genotypic characteristics of mecA - positive oxacillin-sensitive Staphylococcus aureus isolated from patients with bloodstream infection in a tertiary hospital in Southern Brazil.
Staphylococcus aureus are extremely important microorganisms, either from an epidemiological point of view or as a pathogen, responsible for causing a series of infectious processes, whether simple, restricted to the skin, or invasive infections such as bacteremia. The emergence of Oxacillin Sensitive-Methicillin Resistant S.aureus (OS-MRSA) isolates has imposed difficulties in the treatment of patients with staphylococcal infection, as such isolates can be mistakenly classified as sensitive and lead to failure of the therapy used. Thus, the objective of this study is to evaluate the prevalence, and genotypic and phenotypic characteristics, of OS-MRSA isolates, from bloodstream infections, collected from patients admitted to a hospital in southern Brazil, as well as to evaluate the treatment used. For this, 801 unique isolates of S. aureus, collected from blood cultures, between January 2011 and December 2020 were evaluated. Of these, 96 isolates were classified as sensitive to oxacillin. The isolates were identified and had their sensitivity profile performed by manual and automated methods. The minimum inhibitory concentration for vancomycin, daptomycin, oxacillin, linezolid and teicoplanine was performed by e-test. The mecA, vanA genes, typing of the SCCmec elements, as well as the search for the icaA, tst-1 and pvl virulence genes were performed by PCR. Biofilm formation was performed using the crystal violet technique. The Sequence Type (ST), as well as the Clonal Complex (CC) of the isolates was evaluated by the RTq -PCR. The clinical characteristics of the patients were evaluated through an active search in medical records. After investigating the mecA gene, 27.1% (26/96) of the isolates were considered OS-MRSA, with SCCmec type I being the most prevalent, 46.1% (12/26). Among the evaluated isolates, 41% (9/22) were included in CC5 and ST9. As for virulence, all isolates were positive for the icaA gene and characterized as strong biofilm formers. The pvl gene was found in 92.3% (24/26) of the isolates and the toxic shock syndrome toxin was present in 61.5% of the isolates (16/26). All isolates were negative for the presence of the van A gene. As for the clinical outcome, 73% (19/26) of the patients were discharged from the hospital and 27% (7/26) died. It was possible to observe a high frequency of OS-MRSA isolates causing bloodstream infections. Furthermore, such isolates contain several virulence genes, which may contribute to a worse clinical outcome.
PubMed: 38896343
DOI: 10.1007/s42770-024-01420-z -
Frontiers in Pediatrics 2024infections are a significant cause of morbidity and mortality in pediatric populations worldwide. The Staphylo Research Network conducted an extensive study on...
BACKGROUND
infections are a significant cause of morbidity and mortality in pediatric populations worldwide. The Staphylo Research Network conducted an extensive study on pediatric patients across Colombia from 2018 to 2021. The aim of this study was to describe the epidemiological and microbiological characteristics of in this patient group.
METHODS
We analyzed isolates from WHONET-reporting centers. An "event" was a positive culture isolation in a previously negative individual after 2 weeks. We studied center characteristics, age distribution, infection type, and antibiotic susceptibilities, comparing methicillin sensitive (MSSA) and resistant (MRSA) isolates.
RESULTS
Isolates from 20 centers across 7 Colombian cities were included. Most centers (80%) served both adults and children, with 55% offering oncology services and 85% having a PICU. We registered 8,157 culture isolations from 5,384 events (3,345 MSSA and 1,961 MRSA) in 4,821 patients, with a median age of 5 years. Blood (26.2%) and skin/soft tissue (18.6%) were the most common infection sources. Most isolates per event remained susceptible to oxacillin (63.2%), clindamycin (94.3%), and TMP-SMX (98.3%). MRSA prevalence varied by city (<0.001), with slightly higher rates observed in exclusively pediatric hospitals. In contrast, the MRSA rate was somewhat lower in centers with Antimicrobial Stewardship Program (ASP). MRSA was predominantly isolated from osteoarticular infections and multiple foci, while MSSA was more frequently associated with recurrent infections compared to MRSA.
CONCLUSIONS
This is the largest study of pediatric infections in Colombia. We found MSSA predominance, but resistance have important regional variations. remains susceptible to other commonly used antibiotics such as TMP-SMX and clindamycin. Ongoing monitoring of infections is vital for understanding their behavior in children. Prospective studies within the Staphylored LATAM are underway for a more comprehensive clinical and genetic characterization.
PubMed: 38895192
DOI: 10.3389/fped.2024.1386310 -
Cureus May 2024Background and objective Urinary tract infections (UTIs) are a common infectious disease affecting people of various ages and genders and are prevalent in different...
The Prevalence of Multidrug-Resistant Uropathogenic Bacterial Profile With Antibiotic Susceptibility Patterns Among the Community and Hospitalized Patients During COVID Waves.
Background and objective Urinary tract infections (UTIs) are a common infectious disease affecting people of various ages and genders and are prevalent in different geographical locations. However, the way Gram-positive and Gram-negative (UTI) germs react to antibiotic treatment varies significantly. The coronavirus disease 2019 (COVID-19) pandemic has increased the frequency of secondary bacterial superinfection, leading to a spike in ongoing recommendations for antibiotic treatment, both therapeutic and preventative. In this study, we aimed to assess uropathogenic bacterial resistance and shed light on how COVID-19 epidemic waves influence the evolution of bacterial resistance. Materials and methods A cross-sectional study was conducted, assessing the different isolates of the uropathogen in all COVID-19 waves by using convenience sampling from August 2020 till the end of 2023. The VITEK-2 compact system employing industry-standard bacteriological tests to identify the bacteria and confirm their antibiotic susceptibility was utilized. Results Of the total 3877 patients, 381 (9.8%) and 3483 (89.8%) had positive and negative microbial growth, respectively. Of the 381 (9.8%) positive cases, 130 (34%) were male and 251 (65%) were female; 138 (43.3%) patients in the age range of 15-40 years developed sporadic UTIs attributed to Gram-negative bacteria. Alternatively, patients over 40 years had the highest prevalence rate (n = 180, 56.6%). The most common strains of Gram-negative and Gram-positive bacteria were and with278 (88.8%) and 13 (20.9%) cases respectively. People with Gram-negative bacteria who were not hospitalized were very resistant to trimethoprim/sulfamethoxazole (n = 219, 69.1%), cefotaxime (n = 193, 60.9%), ampicillin (n = 192, 60.6%), and amoxicillin/clavulanic acid (176, 55.5%). While high sensitivity to meropenem (n = 14, 4.4%) and imipenem (n = 13, 4.1%) was observed, hospitalized individuals had higher levels of resistance and great sensitivity to the same antibiotics. S. . were commonly present. Hospitalized patients were less sensitive to benzylpenicillin, ampicillin, and oxacillin, and there was a big rise in resistance to cefoxitin in the community. Conclusions In this study, Gram-negative germs among females were predominantly observed with extremely high multi-drug resistance (MDR). The most effective antibiotics against Gram-positive germs included linezolid, vancomycin, and nitrofurantin, while those against Gram-negative bacteria were meropenem and amikacin. Clinicians should be regularly updated and informed about antibiotic selection through routine monitoring of uropathogenic bacteria's susceptibility. Moreover, we recommend changes to the local antibiotic policy regarding the selection of UTIs; further multicentric and high-volume studies are required to gain deeper insights into the topic.
PubMed: 38894805
DOI: 10.7759/cureus.60613