Pneumonia, responsible for threemillion deaths annually worldwide, remains a leading cause of death from hospital-acquired infections. Unfortunately, treatment in most cases is empirical and not based on microbiological data because of difficulty in obtaining reliable lower respiratory tract specimens as they are frequently contaminated by upper respiratory tract bacterial flora. We examined aseptically collected lung specimens from decedents with fatal pneumonia to (a) isolate the multi-drug-resistant gram-negative bacteria (MDR GNB) and analyze their antimicrobial susceptibility profiles and resistance phenotypes to beta-lactams and (b) determine the factors associated with fatal MDR GNB pneumonia. This was a cross-sectional, descriptive autopsy-based study conducted between June-December 2024 at the Mulago National Referral Hospital mortuary and the Clinical Microbiology Laboratory at Makerere University College of Health Sciences, Kampala, Uganda. Deceased adults, within a postmortem interval not exceeding 20hours, with an ante-mortem diagnosis of pneumonia or other lower respiratory tract infections were included. Lung tissue and or aspirates were collected, processed, and analyzed microbiologically for bacterial identification, susceptibility testing, and detection of resistance phenotypes to beta lactams. Overall, 120 adults died during hospitalization at Mulago Hospital with a primary diagnosis of pneumonia in the period of June to December 2024; of whom 60/100 (50%) were female. The mean age was 50.2 (16.6) years, and the median duration of hospitalization was 42.5 (Inter-quartile range 19.0-80.0) hours. Nearly half (53/120, 44%) were referrals from private health care facilities while 43 (35.8%) were from public health care facilities. Thirty-two (32/120, 26.7%) were confirmed to be living with HIV and 59/120 (49%) had other co-morbidities. One hundred three (103/120, 85.8%) had received empirical antibiotic treatment without microbiological investigations. Bacteria isolated from lung tissue/aspirates were Klebshiella pneumoniae species in 54(45.0%) patients, Escherichia coli in 33(27.5%), Pseudomonas aeruginosa in 17(14.2%) and Acinetobacter species in 12(10.0%) of the patients. The bacteria isolates were resistant to most of the antibiotics used for empirical therapy with resistance to Ceftriaxone at 86.7%, Piperacillin-tazobactam at 44.2%, Coamoxiclav 46.7% and Meropenem at 21.7%. Amikacin and Tigecycline had the least resistance at 20% and 14.3% respectively. Overall, Cabarpenem resistance (defined by resistance to either Imipenem or Meropenem or Ertapenem) was observed in 60/120 (50%) of patients. Patients who had pneumonia with co-morbidities were 2.5 times more likely to have Cabarpenem resistance; Odds Ratio, OR (95% Confidence interval (CI) 2.51(1.07 to 5.87); p value =0.033 and patients who were referred from private health care facilities were almost 5 times more likely to have Cabarpenem resistance; OR 4.92 (CI 1.35 to 17.9); p-value= 0.016. Multidrug resistant gram-negative bacteria were responsible for all fatal bacterial pneumonia during hospitalization. Patients with co-morbidities and referrals from private clinics had higher risk of carbapenem resistance.

BackgroundAllergies to BLA may affect ∼10% of the population, few are IgE-mediated, and cross-reactivity between agents is low. Removing CSAs from EHRs may increase BLA use. Impact of such interventions on prescribing behavior, interactions with EHR alerts, and antibiotic administration patterns is poorly understood.Table 1.Characterization of Beta Lactam Cross-Sensitivity Alerts and Clinician Actions to Alert ContactsTable 2.Antibiotic and Epinephrine Administration during Inpatient Encounters within 24 Hours Following Index Cross Sensitivity Alert Triggered by Beta-Lactam Orders in Beta Lactam Allergic PatientsMethodsA quality improvement (QI) intervention consisting of suppression of CSAs for BLA orders within our Epic Systems™ EHR, clinician education, guideline and order set updates was undertaken at a large academic hospital. CSA contacts by clinicians (excluding verifying pharmacist and one step intraoperative anesthesiologist orders) during an index inpatient BLA order for BLA allergic patients pre- (10/1/2022 -3/31/23) and post- (10/1/2023 – 3/31/2024) were reviewed. Confounding alerts for multiple beta-lactam allergies were excluded, no exclusions were made for allergy type, severity, or treatment indication. Actions taken in response to the alert or lack thereof were compared pre and post intervention (Table 1). Systemic antibacterial administrations and intramuscular (IM) epinephrine within 24 hours of alert contact were evaluated. Statistical analysis was conducted using chi square and fisher’s exact test in GraphPad Prism version 2025.ResultsTotal 18761 CSA contacts were examined, encompassing 11255 inpatient encounters for 6539 unique patients. Baseline overall alert override rate was variable relative to clinician role, with an average of 57.52% override expectedly decreasing to 0.06% (p < 0.00001) postintervention (Table 1). Inpatient encounters for BLA allergic patients triggering an index CSA via a BLA order were more likely to incur documented administration of any antibacterial (57% vs 75%, P< 0.001) with higher proportion of beta lactams (82% vs 91.3%, P< 0.001). There was no difference in IM epinephrine administrations (Table 2).ConclusionA comprehensive QI intervention focused on suppression of frequently overridden BLA CSAs enhanced likelihood of allergic patients receiving BLA at index inpatient antibiotic prescribing, without an increase in severe immediate anaphylactic reactions requiring epinephrine. More studies are needed to evaluate the impact of such interventions on stewardship goals in BLA allergic patients.DisclosuresDavid Dobrzynski, Jr., MD, DynaMed: Advisor/Consultant|Innoviva Therapeutics Inc: Advisor/Consultant

BackgroundSolid organ transplant recipients (SOT) are at high risk for infections, including gram-negative bacteremia caused by Enterobacterales. While intravenous (IV) antibiotics (abx) are often used, recent studies in immunocompetent patients show that oral abx can be equally effective with fewer adverse events. Data in solid organ transplant recipients is limited, particularly regarding oral beta-lactams (BL).MethodsThis retrospective cohort study included adult SOT recipients admitted to the Houston Methodist Hospital System between June 2016 and September 2023 with a first episode of Enterobacterales bacteremia. Patients discharged on either oral BL or IV antibiotics after initial IV therapy were included. Those with deep-seated infections requiring prolonged antibiotic treatment were excluded. The primary outcome was a composite endpoint of all-cause mortality, recurrence of infection, re-initiation of antibiotics, or unplanned healthcare visit within 30 days of antibiotic completion.ResultsA total of 864 bacteremic patients were identified, and 182 were included: 105 in the oral BL arm and 77 in the IV arm. The median patient age was 59.5 years, and 104 of the patients were female. Urinary tract infections were the most common source with 131 cases, and Escherichia coli was the predominant organism with 135 cases. Patients in the BL arm received a median of 6 days of IV therapy before being transitioned. Of these, 37 (35%) in the BL group, 34 (44%) in the IV group met the primary composite endpoint (p=0.22). There were no significant differences in 30-day bacteremia recurrence, 30-day source recurrence, unplanned healthcare visits, or reinitiation of antibiotics between the oral BL group and the IV group. Adverse events and Clostridioides difficile infection rates were low across all groups without significant differences.ConclusionAmong SOT recipients treated for gram-negative bacteremia, step down therapy with oral BL were not associated with worse outcomes compared to IV abx. These findings suggest oral BL may be a reasonable step-down option in transplant patients with gram-negative bacteremia without deep-seated infections and further prospective studies are warranted to confirm these results.DisclosuresAll Authors: No reported disclosures

BackgroundInfection is the second leading cause of maternal death, commonly resulting from conditions such as chorioamnionitis, endometritis, and postabortal infections. The American College of Obstetrics and Gynecologists recommends a regimen of ampicillin with gentamicin, along with clindamycin or metronidazole, or vancomycin if beta lactam allergies are present. These combinations remain the standard-of-care antibiotic regimen but are largely informed by older data. More recent studies have demonstrated both efficacy and safety of alternative antibiotics including the usage of beta-lactams. In this study, we reviewed our local microbiology data and implemented a pathogen-directed, antibiogram-guided update to our institutional standard of practice. We developed an electronic health record (EHR) obstetric order set for our health system from this review.Total Cultures EvaluatedPositive cultures of clinically relevant bacteria from Ob-Gyn patients who developed infections post-childbirth between 2020-2023.Updated AntibiogramSample culture susceptibilities of clinically relevant pathogens were compiled across 3-hospitals within Montefiore Medical Center using samples from all anatomical sitesMethodsWe reviewed our local obstetrics and gynecology microbiology and resistance data for all clinical cultures obtained in our outpatient gynecology practices and inpatient obstetric triage and admission units. Based on culture results, we created an OB-specific antibiogram. We used it to guide and develop a new institutional antibiotic guidance and EHR obstetric order set.Peripartum Antibiotic GuidanceResultsBetween 2020-2023 we evaluated a total of 695 cultures from all anatomical sites. Total of 320 pathogens were speciated from non-urine samples vs 374 from urine samples. An antibiogram was produced based off these samples, directed towards clinically relevant pathogens. Based on the new antibiogram, antibiotic guidance was developed for patients with severe and non-severe infections. For non-severe patients, cefoxitin and ampicillin with the possible addition of azithromycin (for suspected concurrent atypical organisms) was recommended. For patients with severe infections, ertapenem and vancomycin with the possible addition of azithromycin was recommended.ConclusionA new pathogen-directed, antibiogram-guided antibiotic treatment guidance was developed for treatment of peri- and postpartum infections. Clinician education and practice guidance is provided by leveraging EHR via peripartum order set.DisclosuresAll Authors: No reported disclosures

BackgroundCarbapenem Resistant Enterobacterales (CRE) are responsible for life threatening antimicrobial resistant (AMR) infections in developing countries. They colonize the gastrointestinal tract and spread due to poor infection prevention and control (IPC) practices. CRE infections are difficult to treat in these settings because of limited access to effective antibiotics. The West Africa Region is reported to have the highest burden of AMR infections in sub-Saharan Africa and our study aims to describe the rectal carriage of CRE amongst patients attending healthcare facilities in the sub-region.MethodsPatients were screened for CRE by culture of rectal swabs at primary (PHC), secondary (SHC) and tertiary (THC) healthcare facilities in Ibadan, Nigeria and Freetown, Sierra Leone from December 2021 to September 2024. After obtaining consent, demographic and clinical data were collected from patients and their records; and rectal swabs obtained for microscopy culture and sensitivity. Patients with gastrointestinal bleeding and rectal pathology were excluded.ResultsOverall, 591 patients were included, of whom 268(45.3%) were male, 196(33.2%) aged 15-39 years and mean(SD) age was 28.4(23.1) years (Table 1). Ninety (15.2%), 141 (23.9%) and 360 (60.9%) were recruited from PHCs, SHCs and THCs respectively. There were CREs isolated from 76 patients including 51(67.1%) in Nigeria. E. coli were most frequently isolated – 51 (65.8%). There were 5(5.6%), 10(7.1%) and 61(16.9%) CRE isolates from PHCs, SHCs and THCs respectively; this difference was significant (P=0.001). No CREs isolated from PHCs in Sierra Leone. There were no significant differences in CRE colonization by gender, age, admitting specialty and pathogen. All CRE isolates were resistant to meropenem and cefepime and had at least 95% resistance to the other beta lactams (Table 2). Overall resistance was 11.8% and 15.7% to tigecycline and colistin respectively.ConclusionThis is the first study to demonstrate CRE rectal colonization at all levels of care in West Africa. There is a need to implement IPC measures within healthcare facilities and communities to prevent their spread. Further studies are needed to understand risk factors for CRE colonization and approaches to effective treatment.DisclosuresAll Authors: No reported disclosures

In paediatric intensive care units (PICUs), beta-lactam antibiotic administration is often suboptimal, placing critically ill children at risk. We aimed to investigate the mortality, PICU length of stay, and pharmacokinetic/pharmacodynamic (PK/PD) benefits of prolonged beta-lactam infusions in PICU compared to intermittent infusions. A systematic review was conducted to identify studies investigating prolonged infusions compared to intermittent infusions. Studies were sourced from a previously published review and a systematic search of MEDLINE, Cochrane, Embase and Web of Science databases. Case reports, case series, systematic reviews and non-English language reports were excluded (PROSPERO CRD 42022375397). A meta-analysis with odds ratios (OR) and 95% confidence intervals (CIs) was conducted. When insufficient data were available, a descriptive analysis was undertaken. Risk of bias was assessed using the Robins-I tool. In total, 566 studies were screened, of which 10 studies were included in the systematic review. All studies were observational, with sample sizes from 21 to 174 PICU patients (median 76; IQR 33-156). There was no reduction in mortality (N = 6 studies; OR 0.60; 95% CI 0.24, 1.51; I2 = 40%) in the prolonged infusion group compared to the intermittent group. There was insufficient data to perform further meta-analyses. The risk of bias was high and the overall quality of evidence was low. Available studies on prolonged infusions of beta lactams in PICU patients are limited and of low quality. Further research is needed to assess for clinical benefits associated with prolonged beta-lactam infusions for treatment of severe infection.

Background: Streptococcus agalactiae, also known as Group B streptococcus (GBS), is an uncommon but highly virulent cause of Infective Endocarditis (IE). It is associated with elevated mortality and morbidity given its rapidly destructive nature, and no treatment guidelines currently exist. Here we present the largest systematic review to date regarding this pathogen causing Infective Endocarditis. Research Question: What are the key demographics, characteristics, complications, and management strategies in groups with GBS? Are there differences in medico-surgical vs medical management in these patients? Methods: A systematic literature review was conducted with: “Group B Streptococcus” AND “Infective Endocarditis”. All types of GBS and IE were included. Studies were excluded if no IE was present or duplicated. Key variables such as underlying medical conditions, types of complications, antibiotic type and length of treatment, type and timing of surgery, type of valvular involvement, median days till recovery or death were collected. The data was stratified for differences in medical and medico-surgical groups. Results: A total of 71 (50.3%M 50.6%F) cases were identified that met inclusion and exclusion criteria. Most common underlying medical conditions were Diabetes Mellitus (15.5%) followed by alcohol use disorder (12.6%), and hypertension (12.6%). Various complications were noted with Heart Failure being the most common (22.5%), Septic Emboli (15.4%), Septic Shock (14.1%). Antibiotics most commonly used were beta lactams (85.9%), aminoglycosides (48%) in combination with beta lactams. Surgeries most commonly performed were Mitral Valve Replacement (36.6%), Aortic Valve Replacement (23%), Homograft Root Replacement (10%). Time to surgery median was 12.5 days. Cumulative mortality rate overall was 42.2% (30 patients). Medico-surgical group mortality rate was 41.6% whereas medical group mortality was 42.8% (15 patients), with early surgery (&lt; 9 days) rate at 42.8%. Combination aminoglycoside and beta lactam antibiotic alone showed 48.1% mortality. Conclusions: GBS endocarditis remains a rare but aggressive infection marked by high complication and mortality rates, regardless of treatment approach. While both medical and medico-surgical management show similarly poor outcomes, the lack of clear survival advantage with early surgery or specific antibiotic regimens highlights the urgent need for standardized treatment guidelines.

Knowledge gap on the susceptibility of novel β-lactam agents (cefiderocol, ceftazidime-avibactam, imipenem-cilastatin-relebectam, and aztreonam) against carbapenem-resistant Enterobacterales (CRE) has been recognized. This study aimed to genotypically characterize CRE isolates and investigate the novel β-lactam activity against CRE. CRE is defined as Enterobacterales that is phenotypically non-susceptible to any carbapenems, including imipenem, meropenem, and ertapenem. A total of 154 CRE isolates were collected from two tertiary centers in Malaysia from October 2023 to May 2024. Carbapenemase-producing genes (blaNDM, blaOXA-48, blaKPC, blaVIM, and blaIMP,) were detected using PCR. Susceptibility to β-lactams was determined using disc diffusion. Of 154 CRE isolates, 102 (66.2%) were carbapenemase-producing carbapenem-resistant Enterobacterales (CP-CRE). blaNDM (76/102; 74.5%), blaOXA-48-like (17/102; 16.7%), blaNDM & blaOXA-48-like (8/102; 7.8%), and blaNDM & blaVIM (1/102; 1.0%) were identified among the CP-CRE isolates. The proportion of CRE isolates that exhibited susceptibility towards cefiderocol, ceftazidime-avibactam, and imipenem-cilastatin-relebactam was 86.4% (133/154), 41.6% (64/154), and 26.0% (40/154), respectively. Among blaNDM-harboring isolates, cefiderocol (57/76; 75.0%) demonstrated superior activity compared with ceftazidime-avibactam (3/76; 3.9%) and imipenem-cilastatin-relebectam (1/76; 1.3%). Among isolates harboring blaOXA-48-like, cefiderocol, ceftazidime-avibactam, and imipenem-cilastatin-relebectam demonstrated 100% (17/17), 70.6% (12/17), and 17.6% (3/17) susceptibility, respectively. Nine isolates that harbored two genes (eight blaNDM + blaOXA-48-like, one blaNDM + blaVIM) demonstrated 100% susceptibility to cefiderocol but 100% resistance to ceftazidime-avibactam and imipenem-cilastatin-relebectam. The ceftazidime-avibactam plus aztreonam combination achieved 100% susceptibility in isolates harboring metallo-β-lactamases-producing genes; blaNDM (76/76; 100%), blaNDM + blaOXA-48-like (8/8; 100%), and blaNDM + blaVIM (1/1; 100%). blaNDM was the most prevalent gene causing CRE. Cefiderocol has the greatest activity compared with other investigated β-lactams.IMPORTANCECarbapenem-resistant Enterobacterales (CRE) has been recognized as a priority and public health concern requiring urgent attention for the development of effective antimicrobial resistance (AMR) prevention and control strategies. Differentiating between carbapenemase-producing CRE (CP-CRE) and non-CP-CRE, along with identifying carbapenemase-producing genes, is essential for guiding targeted antibiotic therapy. Among novel β-lactam agents, cefiderocol and the combination of ceftazidime-avibactam and aztreonam have shown promising activity against blaNDM-producing CRE, supporting precision medicine approaches. Nevertheless, our study observed the emergence of cefiderocol resistance in isolates without prior drug exposure, highlighting a potential challenge in combating AMR.

Pharmacist engagement in allergy clarification has demonstrated increased appropriate antibiotic use. The purpose of this study was to determine the knowledge and confidence of pharmacy students in their final professional year regarding beta-lactam (BL) allergies. Students from 5 schools of pharmacy participated in a 22-question survey pertaining to experience with drug allergies, knowledge of BL allergies, and confidence regarding BL allergy management. Data were summarized among all respondents and further analyzed by infectious disease (ID) interest. A total of 160/521 students responded to the survey (31%). Most students (73%) had no course dedicated to drug allergies; however, 84% indicated the topic was taught within the curriculum. Students with an ID interest had a higher perceived knowledge regarding the details of penicillin skin testing (62% vs. 32%), clinical implications of penicillin skin test results (87% vs. 70%), and the principles behind a graded and direct penicillin challenge (64% vs. 41%). These students were more confident in educating patients about a perceived penicillin allergy (34% vs. 15%). Perceived knowledge and confidence of BL allergies were low, especially in high-level interventions. Targeted training in beta-lactam allergy recognition and management within the curriculum should be considered to improve upon these findings.

Background: aerobic, non-spore forming Non-Fermenting Gram-Negative Bacilli (NFGNB) are significant nosocomial agents. They can cause infections such as bacteraemia, meningitis, pneumonia, urinary tract infection and osteomyelitis especially in immunocompromised hosts. Identification and monitoring of susceptibility pattern thus become of utmost importance in the management of these Multidrug Resistant (MDR) pathogens. The aim of this study was to determine the isolation rate of NFGNB along with its susceptibility pattern in all the clinical samples. Materials and Methods: the study was conducted in the Microbiology Department of a tertiary care hospital. The NFGNB were identified using a standard protocol that included tests for motility, oxidase production, oxidation-fermentation test, gelatin liquefaction, and utilization of 10% lactose. Antibiotic susceptibility testing was performed with Kirby-Bauer disc diffusion method. Results: from a total of 15847 samples 935 (5.90%) NFGNB were isolated. Acinetobacter spp. (50.37%) and Pseudomonas spp. (47.05%) were the most common NFGNB isolated followed by Burkholderia cepacia complex (2.4%) and Stenotrophomonas maltophilia (0.2%). High resistance was observed for cephalosporins, monobactams and quinolones in Pseudomonas aeruginosa. In Acinetobacter spp. high resistance was observed for cephalosporins, cotrimoxazole and Beta Lactam and Beta Lactamase Inhibitor (BL-BLI) combination and quinolones. Conclusions: NFGNB have emerged as an important nosocomial agent, therefore early detection in routine laboratory, monitoring susceptibility pattern, immediate infection control and antimicrobial stewardship programs should be implemented in order to limit the spread of MDR organisms.

Assessing multi-drug resistance in Streptococcus agalactiae infecting farmed Nile Tilapia: Findings from Kerala, India.

Characterization of Beta Lactam Allergy and Outcomes Associated with Perioperative Antibiotic Choice in Kidney Transplant Recipients

Objectives: To explore whether vancomycin (VAN) plus piperacillin-tazobactam (PTZ) was associated with an increased risk of acute kidney injury (AKI) compared with VAN plus other beta-lactams (BLs) or monotherapy in critically ill patients, where the evidence remains controversial. Data sources: PubMed, Cochrane, Web of Science, and Embase were searched from inception to June 2024. Study selection: Studies comparing the risk of AKI with one group receiving VAN+PTZ, and other groups receiving VAN plus other BLs, or monotherapy in critically ill. Data synthesis: This analysis included 20 articles with 28 243 participants. The majority of included studies were retrospective (95%, 19/20) and had moderate risks of bias (80.0%, 16/20). The results indicated VAN+PTZ was associated with a significantly higher risk of AKI compared with VAN plus other BLs (OR = 1.66, 95% CI = 1.42-1.94, P < 0.001). Subgroup analyses showed that compared with adults, children were associated with a higher risk of AKI when receiving VAN+PTZ (OR = 3.16 vs 1.59). Also, VAN+PTZ was associated with a significantly higher risk of severe stage 2 to 3 AKI than VAN plus other BLs (OR = 1.63, 95% CI = 1.28-2.06, P < 0.001). No significant difference was identified in mortality, dialysis, time to AKI, and length of stay between patients receiving VAN plus PTZ and other combinations. Conclusions: In critically ill, VAN plus PTZ was associated with an increased risk of AKI and severe stage 2 to 3 AKI compared with VAN plus other BLs, especially in children. However, more high-quality multicenter, prospective cohort studies, and randomized controlled studies are needed.

Background/Objective: This study aimed to evaluate the effectiveness of very early oral transition in Enterobacterales bloodstream infections (E-BSIs), identify factors associated with it, compare the effectiveness of different oral options, and assess its economic and ecological benefits. Methods: Retrospective, observational cohort study including monomicrobial E-BSI in clinically stable adult patients by day 3 of bacteremia with oral antibiotic options. Transition to oral antibiotics by day 3 or earlier (early oral (EO) group) was compared to later transition or remaining on intravenous therapy (nEO group). Early oral transition-associated factors were analyzed. Oral high-dose beta-lactams (BLs) were compared to quinolones (QLs) or trimethoprim/sulfamethoxazole (TS). Economic and ecological costs were assessed. Results: Of 345 E-BSI, 163 (47.2%) were in the EO group, characterized by more urinary tract infections (UTIs) and shorter hospital stays. The nEO group had higher Charlson Comorbidity Index (CCI), extended-spectrum beta-lactamase (ESBL) production, greater source control need, and longer time to clinical stability. There were no significant differences in mortality and relapse. UTIs were associated with early oral transition (OR 2.02, IC 95% 1.18–3.48), while higher CCI (0.85, 0.77–0.95), source control need (0.39, 0.19–0.85), longer time to clinical stability (0.51, 0.39–0.66), and ESBL isolates (0.39, 0.19–0.80) hindered this practice. High-dose BLs and QL/TS were equally effective. Early oral transition resulted in 38.794 KgCO2eq reduction and EUR 269,557.99 savings. Conclusions: Very early oral transition at day 3 or before in stable E-BSI patients is effective, eco-sustainable, and cost-effective; UTI is related with the early oral switch, while comorbidities, ESBL production, source control need, or longer time to clinical stability hinder this practice.

Introduction: Beta-lactam (BL) antibiotics are the most commonly implicated drugs in pediatric drug hypersensitivity reactions. However, most children with suspected BL allergy can safely tolerate these antibiotics after careful evaluation. The aim of this study was to evaluate the clinical characteristics, diagnostic work-up results, and risk factors associated with confirmed BL allergy in children referred with suspected BL hypersensitivity. Methods: We retrospectively analyzed 158 children referred for suspected BL allergy between 2019 and 2025. Clinical and demographic data were collected from medical records. Diagnostic evaluation included skin testing and drug provocation testing. Patients were divided into two groups: those with confirmed BL allergy and those whose allergy label had been removed. Risk factors for BL allergy were compared between groups. Results: The cohort included 158 children (58% male; median age: 100.5 months; interquartile range [IQR]: 75–150.75). The median time from reaction to clinical evaluation was 7 months (IQR: 3–25). The most commonly implicated drug was amoxicillin/clavulanate (81.5%). Immediate reactions (IR) occurred in 47.8% of cases. BL allergy was confirmed in 36.7% of the cases. In the final logistic regression model, the type of hypersensitivity reaction (p = 0.001), severity of reaction (p = 0.001), and the presence of comorbidities (p = 0.008) remained significant predictors of confirmed drug allergy. Conclusion: Given the low true allergy rate, accurate diagnosis and delabeling of suspected BL allergy in children is essential to avoid unnecessary antibiotic restriction.

Abstract Background Beta Lactam Resistance is an ever increasing global phenomenon. Tracking both the phenotypic and molecular incidence of β-lactam resistance is of paramount importance. Objectives To (i) use AST methods to gain an understanding of the extent of antimicrobial resistance of Pseudomonas aeruginosa and Escherichia coli in Trinidad and Tobago; and (ii) use PCR to understand the molecular basis of antimicrobial resistance in P. aeruginosa and E. coli in Trinidad and Tobago. Materials and Methods The study collected 132 Pseudomonas aeruginosa and 154 E. coli and used phenotypic methods to detect antimicrobial susceptibility. The Polymerase Chain reaction (PCR) was used to identify six ESBL genes (TEM SHV, CTX, AmpC, KPC and OXA in the samples. Results Of the E.coli samples collected, 52 (33.8%) of them were cephalosporin resistant, while among the P. aeruginosa samples, 31 (23.5%) of the samples were cephalosporin resistant. 9.2 % of the E. coli samples and 23.4 % of the P. aeruginosa samples were found to be carbapenem resistant. Of the Pseudomonas isolates tested, SHV, CTX, AmpC, OXA and KPC genes were found and within the E. coli samples TEM, SHV CTX and OXA genes were found. More than one gene was detected in some isolates. Conclusions The results described in this study represent the first and most comprehensive published phenotypic analysis of cephalosporin and carbapenem resistance of both E. coli and P. aeruginosa in Trinidad and Tobago. The rates of resistance are in line with other studies that have been published internationally. This represents the first time the OXA gene has been described in Trinidad and Tobago and the first time that SHV and CTX type β-lactamase genes have been described in Pseudomonas isolates in Trinidad. This study provides opportunity for more research to be conducted on Gram-negative isolates in Trinidad and Tobago and the Caribbean region as many of the tested resistant isolates did not possess any of the genes interrogated, implying that other yet undescribed molecular causes may be responsible. New ESBL and carbapenemase variants have been described in samples showing antimicrobial resistance in Trinidad and Tobago. These findings contribute to the wealth of knowledge of the molecular mechanisms of antibiotic resistance globally but also provide opportunities for further study.

Background: Methicillin resistant Staphylococcus aureus (MRSA) infections are of great risk to health because they are resistant to most common antibiotics and affixed to hospital acquired and community acquired infections. An evaluation of the antimicrobial resistance patterns of MRSA isolates from blood samples collected in Lahore, Pakistan is performed and prevalence as well as susceptibility trends for MRSA are reported. Objective: The purpose of this study was to determine the drug resistance patterns of MRSA isolates and assess their susceptibility to different agents, both beta lactam and non-beta lactam. Methods: A total of 103 fresh blood sample specimens were investigated using the standard protocols. Colonies were cultured on blood agar plates and Gram stained and the following biochemical tests (catalase and coagulase tests) for the identification of S. aureus were performed. Kirby Bauer method was used for antimicrobial susceptibility testing on Muller Hinton agar using antibiotic discs for ciprofloxacin, clindamycin, piperacillin/tazobactam, gentamicin, linezolid, penicillin, teicoplanin, vancomycin, and cefoxitin. Results: Of 103 blood samples of MRSA, 30 had growths of MRSA. The results indicated that all MRSA isolates were resistant to cefoxitin and penicillin with 100% beta lactam resistance. On the other hand, vancomycin, teicoplanin and linezolid showed 100% susceptibility, which makes them good therapeutic options. In this study, resistance rates for clindamycin, tazobactam and gentamicin were found to be 33.3%, 23.3% and 26.7%, respectively. The resistance rate of ciprofloxacin was 63.3%. Conclusions: Beta lactam antibiotics resistance of MRSA isolates of Lahore are very high therefore alternative agents like vancomycin, teicoplanin and linezolid are used. Too often, MRSA is treated as a highly primitive bacteria, which has it wrong; these findings highlight the need for more surveillance, routine testing and antibiotics judiciously.”

Enzymes are protein biomolecules that act as catalysts in various biochemical reactions, both in biological systems and industrial applications. The uniqueness of enzymes lies in their ability to accelerate the rate of reactions with a high degree of specificity towards certain substrates without undergoing permanent changes in their chemical structure. Enzyme activity is strongly influenced by various environmental factors, such as temperature, pH, substrate concentration, and the presence of inhibitors or activators. Therefore, quantitative testing of enzyme activity is an important step in understanding the characteristics of enzymes and their applications in various fields. Escherichia coli produces Extended-Spectrum Β-Lactamase Enzyme (ESBL) and plays a role in damaging the structure of beta lactam antibiotics so that the antibiotics cannot kill bacteria. Bacteria that produce ESBLs need to be watched out for because ESBLs are produced by genes located on plasmids, which can easily be transferred to other bacteria, and often also carry resistance genes to other antibiotics. Objective: to accurately measure the activity or concentration of enzymes in samples of Escherichia coli bacteria and understand the influence of variables such as substrate concentration on the reaction rate. Method: spectrophotometry through enzyme extraction, making a standard curve and testing enzyme activity against variations in substrate concentration. Results: samples with concentrations of 0.1 and 0.3 showed good and appropriate absorbance results. However, in the sample 0.5 ; 0.7 ; and 1.0 indicates an absorbance number that is slightly higher than it should be. Conclusion: the enzyme in Escherichia coli bacteria has good activity at sample concentrations of 0.1 and 0.3.

Background: Drug allergies constitute a significant health concern among the elderly, with beta-lactam (BL) antibiotics among the most frequently implicated agents. Nevertheless, data regarding the safety and efficacy of BL allergy de-labeling in this population remain scarce. This study aimed to evaluate the safety and efficacy of BL allergy assessment in a cohort of geriatric patients carrying BL allergy labels. Methods: We conducted a retrospective study, including patients aged >65 years who were referred for BL allergy evaluation at the Allergy Unit of Meir Medical Center. Patients underwent comprehensive anamnesis, skin testing, and, when indicated, oral challenge. Those successfully de-labeled were followed longitudinally to assess subsequent BL use and clinical outcomes. Results: Between 2009 and 2019, 166 elderly patients with suspected BL allergies were evaluated. A BL allergy was ruled out in 145 patients (87.3%). Sixteen patients (9.6%) were diagnosed with immediate-type hypersensitivity, 2.4% of patients had severe delayed-type hypersensitivity reactions, and one patient (0.6%) had a benign rash. The evaluation process was safe, with no severe reactions occurring during oral challenges, and no patient required hospitalization or epinephrine administration. A long-term follow up was available for 106 patients; among them, 38 (35.8%) received subsequent treatment with the previously suspected BL agent, without any reports of immediate or severe delayed reactions. Conclusions: Beta-lactam allergy de-labeling is safe and effective in the elderly and supports the critical role of allergy evaluation in this population. Enhanced awareness and implementation of de-labeling protocols in geriatric patients are warranted.

SUPPRESSIVE ANTIBIOTIC THERAPY: NEW FRONTIERS IN THE MANAGEMENT OF HIGH SURGICAL RISK INFECTIVE ENDOCARDITIS