Narrow-spectrum Antibiotics Research Articles

Bradyrhizobium japonicum FN1 produces an inhibitory substance that affects competition for nodule occupancy.

Bacteriocins are narrow-spectrum antibiotics of bacterial origin that can affect competition in resource-limited environments, such as the rhizosphere. Therefore, bacteriocins may be good candidates for manipulation to generate more competitive inocula for soybean. In this study, Bradyrhizobium japonicum FN1, along with other Bradyrhizobia in our culture collection, was screened for bacteriocin-like activity. Five distinct inhibitory effects were observed. FN1 genes putatively involved in bacteriocin production were computationally identified. These genes were mutagenized, and the subsequent strains were screened for loss of inhibitory activity. Mutant strain BRJ-48, with an insert in bjfn1_01204, displayed a loss of ability to inhibit an indicator strain. This loss can be complemented by the introduction of a plasmid expressing bjfn1_01204 in trans. The strain carrying the mutation did not affect competition in broth cultures but was less competitive for nodule occupancy. Annotation suggests that bjfn1_01204 encodes a carboxymuconolactone decarboxylase; however, the direct contribution of how this enzyme contributes to inhibiting the tester strain remains unknown.

Group B Streptococcal Colonisation among Antenatal Women from a Tertiary Care Centre, Northern Kerala: A Cross-sectional Study

Introduction: Group B Streptococcus (GBS) is the leading cause of neonatal sepsis all over the world. Maternal colonisation of GBS in vaginal and anorectal area poses risk for subsequent invasive disease. The prevalence of maternal colonisation varies with geographical, biological and socio-economical factors. Current recommendations consider maternal screening and antibiotic therapy to prevent GBS neonatal disease with a potential of alteration of infant gut flora. Aim: To find out the prevalence, outcome and antimicrobial susceptibility pattern of the GBS colonisation in antenatal women. Materials and Methods: A hospital-based descriptive crosssectional study was conducted in Government Medical College, Kozhikode, Kerala, India, during December 2017 to May 2019 including 300 antenatal women of 35-37 weeks gestational age. Vaginal and rectal swabs were taken and were subjected to microbiological examination and culture. Data analysis was done by Statistical Package for the Social Sciences (SPSS) version 16.0. The Chi-square test and Fisher’s exact test were used wherever applicable and p-value <0.05 is considered significant. Results: Among the 300 antenatal women, 8 (2.7%) were colonised with GBS. Higher rate of colonisation was observed in women of 21-25 years, higher parity, rural dwelling and in women with poor glycaemic control. All the colonised women received antibiotic prophylaxis with intravenous ampicillin. None of the colonised women or the neonates born to them developed any invasive GBS infection. Antibiotic susceptibility testing showed that all the isolates were sensitive to penicillin, ampicillin and vancomycin but only 62.5% of the isolates were susceptible to clindamycin and 37.5% of the isolates were susceptible to erythromycin. Conclusion: The prevalence of GBS colonisation is low in Asian countries, compared to the data from western countries. Evidence based usage of narrow spectrum antibiotics should be considered. Further studies regarding prevalence, antibiotic susceptibility pattern, cost benefit analysis of the antibiotic usage and its effect on neonatal gut flora etc, including a wider population, is a need of the hour in the setting of emergence of resistance.

Biomarker-guided duration of Antibiotic Treatment in Children Hospitalised with confirmed or suspected bacterial infection (BATCH): protocol for a randomised controlled trial

IntroductionProcalcitonin (PCT) is a biomarker more specific for bacterial infection and responds quicker than other commonly used biomarkers such as C reactive protein, but is not routinely used in the...

Uso appropriato degli antibiotici e stewardship in pediatria

Antimicrobial resistance is a public health problem emerging in all areas of the world, making difficult to treat many common infections. Antimicrobial stewardship is an instrument to fight antimicrobial resistance. Antimicrobial stewardship is a set of procedures aimed at saving as many doses of antibiotics as possible to preserve their future efficacy, limiting the selective pressure on world microbial population. It includes those assessments regarding the administration of antibiotics that start from the correct patient’s selection to start antibiotic treatment, to choose the most suitable molecule and the route of administration, collecting microbiological samples to isolate a microorganism and arrive at any modification of narrow-spectrum antibiotic therapy or even discontinuation of the antibiotic.

Consumo de antibióticos en atención primaria en población adulta de Asturias durante el periodo 2014-2020

Trend study of the consumption of systemic antibiotics in the adult population in of Primary Care of the Health Service of the Principality of Asturias (SESPA) during the period 2014̶2020. Retrospective observational study. SESPA, Primary Care. Population from the Individual Health Card database. Data were collected on the prescription of antibiotics, carried out in the family medicine consultations, dispensed in the pharmacy offices with charge of SESPA. Antibiotic use and consumption variables were analyzed using linear regression models. Prevalence of antibiotic use (population percentage); consumption rate of systemic antibiotics (DTD), relative consumption of narrow-spectrum antibiotics (percentage DDD). The average prevalence of the use of antibiotics for the 2014̶2019 period was 32.2% and 23.9% in 2020. The rate of consumption of systemic antibiotics decreased from 21.4 DTD in 2014 to 12.7 DTD in 2020. The consumption of narrow-spectrum antibiotics remained stable (19.4% DDD in 2014 and 19.3% DDD in 2020) (CI95: −0.10, 0.26). In the period from March to December 2020, the consumption of antibiotics decreased by 28.6% compared to the same period in 2019. In 2014̶2020, the consumption of antibiotics decreased, especially since the COVID-19 pandemic, with stabilization of the consumption of narrow-spectrum antibiotics compared to the total. There is variability in consumption by therapeutic subgroups.

Biodiversity of Escherichia coli bacterial resistance to multidrug isolated on the Dumai coast of Indonesia

Abstract. Feliatra F, Mardalisa M, Efendi I, Adelina A, Feliatra VA. 2021. Biodiversity of Escherichia coli bacterial resistance to multidrug isolated on the Dumai coast of Indonesia. Biodiversitas 23: 10-16. Anthropogenic pollution around the Dumai coast of Indonesia disturbs marine microorganisms, including commensal bacteria such as fecal Escherichia coli. Escherichia coli have often been used as a sensitive indicator for the spread of Antibiotic Resistance Genes (ARGs) among pathogens. This study aimed to analyze the development of E. coli resistance, originating from the Dumai sea waters using six antibiotics against seven E. coli isolates (E1, E4, E6, E8, E11, E13, and E15) at the five stations. Furthermore, a sensitivity test was performed on Mueller Hinton Agar (MHA) solid media, based on the Kirby-Bauer disk diffusion method. The results showed 100% E. coli isolates resistant to narrow-spectrum antibiotics (Penicillin, Isoniazid, Streptomycin, and Erythromycin) at the five stations. Meanwhile, high resistance of E. coli against the broad-spectrum antibiotics was observed in station 4 (mangrove habitat) existed in Chloramphenicol, whilst no resistance was found in Ciprofloxacin. Escherichia coli isolates showed Multidrug Resistant (MDR) index value higher than 0.2 which suggests there is a high-risk of antibiotics pollution in Dumai seawater. Bioinformatics analysis of 16S rRNA gene sequences represents the identity of E. coli isolates at the species level (97.84% - 99.74%). This study revealed the presence of antibiotic pollution in Dumai seawater which may impact public health. Hence, the local community must be discipline about the use of antibiotics freely.

Days of Antibiotic Spectrum Coverage: A Novel Metric for Inpatient Antibiotic Consumption.

Days of therapy (DOT), the most widely used benchmarking metric for antibiotic consumption, may not fully measure stewardship efforts to promote use of narrow-spectrum agents and may inadvertently discourage the use of combination regimens when single-agent alternatives have greater adverse effects. To overcome the limitations of DOT, we developed a novel metric, days of antibiotic spectrum coverage (DASC), and compared hospital performances using this novel metric with DOT. We evaluated 77 antibiotics in 16 categories of antibacterial activity to develop our spectrum scoring system. DASC was then calculated as cumulative daily antibiotic spectrum coverage (ASC) scores. To compare hospital benchmarking using DOT and DASC, we conducted a retrospective cohort study of adult patients admitted to acute care units within the Veterans Health Administration system in 2018. Antibiotic administration data were aggregated to calculate each hospital's DOT and DASC per 1000 days present (DP) for ranking. The ASC score for each antibiotic ranged from 2 to 15. There was little correlation between DOT per 1000 DP and DASC per DOT, indicating that lower antibiotic consumption at a hospital does not necessarily mean more frequent use of narrow-spectrum antibiotics. The differences in each hospital's ranking between DOT and DASC per 1000 DP ranged from -29.0% to 25.0%, respectively, with 27 hospitals (21.8%) having differences >10%. We propose a novel composite metric for antibiotic stewardship, DASC, that combines consumption and spectrum as a potential replacement for DOT. Further studies are needed to evaluate whether benchmarking using the DASC will improve evaluations of stewardship.

Microbiome Compositions and Resistome Levels after Antibiotic Treatment of Critically Ill Patients: An Observational Cohort Study.

Hospitalization and treatment with antibiotics increase the risk of acquiring multidrug-resistant bacteria due to antibiotic-mediated changes in patient microbiota. This study aimed to investigate how broad- and narrow-spectrum antibiotics affect the gut microbiome and the resistome in antibiotic naïve patients during neurointensive care. Patients admitted to the neurointensive care unit were treated with broad-spectrum (meropenem or piperacillin/tazobactam) or narrow-spectrum antibiotic treatment (including ciprofloxacin, cefuroxime, vancomycin and dicloxacillin) according to clinical indications. A rectal swab was collected from each patient before and after 5–7 days of antibiotic therapy (N = 34), respectively. Shotgun metagenomic sequencing was performed and the composition of metagenomic species (MGS) was determined. The resistome was characterized with CARD RGI software and the CARD database. As a measure for selection pressure in the patient, we used the sum of the number of days with each antibiotic (antibiotic days). We observed a significant increase in richness and a tendency for an increase in the Shannon index after narrow-spectrum treatment. For broad-spectrum treatment the effect was more diverse, with some patients increasing and some decreasing in richness and Shannon index. This was studied further by comparison of patients who had gained or lost >10 MGS, respectively. Selection pressure was significantly higher in patients with decreased richness and a decreased Shannon index who received the broad treatment. A decrease in MGS richness was significantly correlated to the number of drugs administered and the selection pressure in the patient. Bray–Curtis dissimilarities were significant between the pre- and post-treatment of samples in the narrow group, indicating that the longer the narrow-spectrum treatment, the higher the differences between the pre- and the post-treatment microbial composition. We did not find significant differences between pre- and post-treatment for both antibiotic spectrum treatments; however, we observed that most of the antibiotic class resistance genes were higher in abundance in post-treatment after broad-spectrum treatment.

1300. Comparison of Narrow vs. Broad Spectrum Antibiotics for Treatment of Community-acquired Aspiration Pneumonia

Abstract Background Aspiration pneumonia (aspPNA) accounts for 5-15% of pneumonia admissions. Despite the absence of risk factors for organisms such as methicillin-resistant S. aureus (MRSA) or Pseudomonas aeruginosa (PsA), broad-spectrum (BS) antibiotics active against these pathogens are frequently prescribed. We compared outcomes of patients receiving narrow-spectrum (NS) versus BS antibiotics for aspPNA. Methods This is a retrospective cohort study of hospitalized patients started on antibiotics for aspPNA upon admission from 1/1/2019 to 12/31/2019. The BS cohort included patients prescribed antibiotics with activity against PsA or MRSA and were on BS antibiotics for > 50% duration of therapy regardless of de-escalation. The primary endpoint was clinical response, defined as resolved, improved, no change, or worsened. Secondary endpoints included 30-day all-cause mortality, duration of therapy, 30-day C. difficile infection, and length of stay. Outcomes were assessed using logistic regression with antibiotic group as a fixed effect, and all analyses were conducted using R v. 4.0.3. Results A total of N=95 patients were included in the study, 35 in the NS and 60 in the BS groups. Clinical response was similar in distribution between groups (p > 0.3). 30-day all-cause mortality was lower in the NS (11.4%) as compared to the BS group (33.3%) (OR 0.26; 95% CI 0.09- 0.81; p < 0.04). There were no differences for the secondary endpoints including median duration of therapy (4 [IQR 2.5] days vs. 6 [IQR 6] days, p> 0.2), 30-day C. difficile infection (0% vs 6.7%, p > 0.3), and median length of stay (6 [IQR 5] days vs. 7 [IQR 8.5] days, p > 0.2) in NS vs. BS groups, respectively. A positive blood or respiratory culture was isolated in 37% (35/95) patients. Enteric organisms were the most prevalent bacteria isolated (20%), followed by methicillin susceptible S. aureus (8%), and Streptococcus spp (7%). MRSA and PsA were detected in 2% and 3% of patients, respectively. Conclusion There is no difference in efficacy between NS and BS antibiotics for aspPNA. Microbiologic data confirm the low incidence of PsA or MRSA causing aspPNA despite high empiric prescribing of antibiotics active against these pathogens. These results support the ongoing need for targeted antibiotic stewardship initiatives for aspPNA. Disclosures All Authors: No reported disclosures

695. Antipseudomonal Versus Narrow-spectrum Agents for the Treatment of Community-onset Intra-abdominal Infections

BackgroundAntipseudomonal antibiotic regiments are often used to treat community-acquired intra-abdominal infections (CA-IAI) despite common causative pathogens being susceptible to more narrow-spectrum agents. The purpose of this study was to compare post-infection complications in adult patients treated for CA-IAI with antipseudomonal or narrow-spectrum regimensMethodsThis retrospective cohort study included patients ≥18 years admitted for CA-IAI treated with antibiotics between January 1, 2013, and December 31, 2019. Patients who had bacteremia or peritonitis were excluded. The primary objective of this study was to compare post-infection complications within 90 days between patients treated empirically with antipseudomonal versus narrow-spectrum regimens. Post-infection complication was defined as post-operative infection, recurrence of diverticulitis, or mortality. Secondary objectives were to compare infection and treatment characteristics along with patient outcomes. Sub-group analyses were planned to compare outcomes of patients with low-risk and high-risk CA-IAI and patients who required surgical intervention versus who were medically managedResultsA total of 350 patients were included: Antipseudomonal, n=204; Narrow-spectrum, n=146. There were no differences in 90-day post-infection complications between groups (Antipseudomonal 15.1% vs Narrow-spectrum 11.3%, p=0.296). Additionally, no differences were observed in hospital LOS, 90-day readmission, C. difficile, or mortality. Patients treated with Antipseudomonal regimens received longer durations of therapy (median 11 days [IQR 8-14] vs 9 days [IQR 5-12], p< 0.001). No differences were observed in 90-day post-infection complications for patient with low-risk (Antipseudomonal 15% vs Narrow-spectrum 9.6%, p=0.154) or high-risk CA-IAI (Antipseudomonal 15.8% vs Narrow-spectrum 22.2%, p=0.588), or those who were surgically (Antipseudomonal 8.5% vs Narrow-spectrum 9.2%, p=0.877) or medically managed (Antipseudomonal 17.5% vs Narrow-spectrum 13.1%, p=0.463). ConclusionPost-infection complication rates were similar among patients treated with antipseudomonal and narrow-spectrum antibiotics. Antipseudomonal therapy is likely unnecessary for most patients with CA-IAIDisclosures Lisa E. Dumkow, PharmD, BCIDP, Nothing to disclose

102. Evaluation of the Association between the Antibiotic Spectrum Index and Antibiotic Days of Therapy: A Retrospective Study across 124 Acute-care Hospitals

BackgroundAntibiotic stewardship programs often measure antibiotic days of therapy (DOT), but this metric does not reflect the antibiotic spectrum. In this study, we used the previously published Antibiotic Spectrum Index (ASI), which attaches a score (1-13) to the spectrum of each antibiotic, to evaluate the content of antibiotic use across all Veterans Health Administration (VHA) hospitals. We also assessed how benchmarking hospital performance changed when ASI was used instead of DOT. MethodsWe conducted a retrospective cohort study of patients admitted to 124 acute-care VHA hospitals during 2018. We obtained data on administered antibiotics, the days of antibiotic use (DOT), and days-present (DP) from the VHA Corporate Data Warehouse and then aggregated data to the hospital-level using the National Healthcare Safety Network’s methodology. We modified the original ASI by changing 3.8% of the bug-drug scores to ensure consistency across all scores and adding 27 new antibiotics agents. For each hospital, we calculated ASI/DOT, ASI/1,000 DP, and DOT/1,000 DP and ranked hospitals on their performance. We performed a Spearman’s rank-order correlation to compare hospitals on these metrics and their associated rankings.ResultsAt the hospital-level, the median ASI/DOT, ASI/1,000 DP and DOT/1,000 DP were 5.4 (interquartile range: 5.2-5.8), 2,332.7 (1,941.8-2,796.2) and 443.5 (362.5-512.2), respectively. There was a strong correlation between the ASI/1,000 DP and DOT/1,000 DP metrics [Spearman’s correlation test: r=0.97 (p< 0.01)] but only a weak and insignificant correlation between ASI/DOT and DOT/1,000 DP [r=0.17 (p=0.06), Figure 1]. Twenty (16.1%) hospitals showed a difference of 10% or more in their ranking for ASI/1,000 DP compared to their ranking for DOT/1,000 DP. The range of ranking difference was from -17.7% to 21.0% (Figure 2a and b).Figure 1. Distribution of the Antibiotic Spectrum Index / Day of Therapy by Days of Therapy / 1000 Days Present for 124 Acute-Care VHA Hospitals during 2018. Black line: Median values of DOT/1,000 DP and ASI/DOT, respectively. Figure 2. (a) Distribution of the rankings in DOT/1,000 DP and ASI/1,000 DP. Blue line: the position of same ranking between ASI/1,000 DP and DOT/1,000 DP. (b) Distribution of the differences in each hospital’s ranking for DOT/1,000 DP and ASI/1,000 DP ConclusionOur findings suggest that hospitals using fewer days of antibiotic therapy did not necessarily use narrower-spectrum antibiotics. ASI/1,000 DP, as a combined measure of antibiotic consumption quantity and average spectrum, provided a different view of hospital performance than DOT/1,000 DP alone. Future work is needed to define how this new metric relates to the quality of antibiotic use. Disclosures All Authors: No reported disclosures

Perioperative antimicrobial prophylaxis in patients undergoing pancreatoduodenectomy: retrospective analysis of bacteriological profile and susceptibility

Background Pancreatic tumours are frequently associated with obstructive jaundice requiring preoperative biliary drainage (PBD) before pancreatoduodenectomy (PD), exposing patients to infectious complications. This study aims to compare postoperative complications after PD with or without PBD and to analyse bile bacteriology and antibiotic susceptibility. Methods All patients undergoing PD between 2014 and 2019 were retrospectively evaluated, and postoperative outcomes were compared according to PBD use. Prophylactic narrow-spectrum antibiotic therapy was given for 24 h, then adapted according to bacteriologic profile. Intraoperative bile cultures and antibiograms were collected. Results Among 164 patients with intraoperative bile culture during PD (75 PBD+, 89 PBD–), an infected bile was observed in 95% and 70% of PBD + and PBD– groups, respectively (p < 0.001). Postoperative mortality and severe morbidity including infectious complications were similar between groups (5% and 15%). The median duration of antibiotherapy was longer in PBD + compared to PBD– groups (9 vs. 2 days, p = 0.009). Malignant indication and PBD were associated with bile contamination using univariate analysis, and PBD was significantly relevant at multivariate analysis. Most common pathogens identified in bile cultures were Escherichia coli, Klebsiella spp. and Enterobacter spp. Overall antibiotic susceptibility to commonly used antibiotics was decreased, including those used in our local guidelines. Conclusions PBD exposes nearly 100% of patients undergoing PD to bile infection and an increased duration of postoperative antimicrobial therapy, without increasing infectious complications in this study. Adaptation of antimicrobial prophylaxis should be further evaluated according to performance of PBD and local epidemiology, in order to avoid overuse of antibiotics.

Impact analysis of expanding narrow-spectrum antibiotic use for children with ear, sinus and throat infections.

Aim: Estimate the impacts treating acute respiratory tract infections (ARTIs) in children aged 6months through 12years with narrow-spectrum antibiotics. Materials & methods: Decision-tree model to estimate children's health, healthcare utilization and costs, and caregiver's time and costs for using narrow-spectrum antibiotics in eligible children with an ARTI, compared with current use of narrow- and broad-spectrum antibiotics. Results: Reduced adverse drug reactions by 35,750 (14%) cases) and 4750 (12%) fewer emergency department visits, 300 (12%) fewer hospitalizations, and 50,500 (10%) avoided outpatient visits. Annual healthcare costs fell by US$120million (22%). Total societal costs declined by US$131million (20%). Conclusion: National implementation of narrow-spectrum antibiotics to treat ARTIs in children improves patient outcomes and reduces caregiver burden and annual healthcare costs.

Antibiotic dispensing during the COVID-19 pandemic: analysis of Welsh primary care dispensing data.

BackgroundThe COVID-19 pandemic led to rapid changes in demand and delivery of primary care services that could have led to increases in antibiotic prescribing.ObjectiveWe investigated the impact of the COVID-19 pandemic on oral antibiotic dispensing rates in primary care in Wales using longitudinal analysis of monthly oral antibiotic dispensing data from 1 April 2018 to 30 April 2021.MethodsWe used All-Wales primary care dispensing data. We examined trends in oral antibiotic dispensing per 1,000 people for Wales and for individual Health Boards. We used interrupted time series analysis to estimate changes in trends pre- and post-April 2020 to assess the impact of the first and subsequent lockdowns.ResultsBetween April 2020 and April 2021, antibiotic dispensing in Wales was lower compared with the same period in 2018 and 2019, with an average monthly decrease of 14.00 dispensed items per 1,000 registered patients (95% confidence interval 19.89–8.11). The overall prepandemic monthly antibiotic dispensing rate ranged from 48.5 to 67.4 antibiotic items per 1,000 registered patients. From the onset of the pandemic, it ranged from 40.3 to 49.07 antibiotic items per 1,000 registered patients. This reduction was primarily driven by narrow-spectrum antibiotics. Statistically significant reductions were also observed for antibiotics commonly dispensed for the treatment of respiratory tract infections. Dispensing of antibiotics primarily used for urinary and skin infections remained stable.ConclusionsDespite complexities of consulting during the COVID-19 pandemic in primary care we found no evidence of an increase in antibiotic dispensing during this time.

Paediatric Antimicrobial Stewardship for Respiratory Infections in the Emergency Setting: A Systematic Review.

Antimicrobial resistance occurs due to the propensity of microbial pathogens to develop resistance to antibiotics over time. Antimicrobial stewardship programs (ASPs) have been developed in response to this growing crisis, to limit unnecessary antibiotic prescription through initiatives such as education-based seminars, prescribing guidelines, and rapid respiratory pathogen (RRP) testing. Paediatric patients who present to the emergency setting with respiratory symptoms are a particularly high-risk population susceptible to inappropriate antibiotic prescribing behaviours and are therefore an ideal cohort for focused ASPs. The purpose of this systematic review was to assess the efficacy and safety of ASPs in this clinical context. A systematic search of PubMed, Medline, EMBASE and the Cochrane Database of Systematic Reviews was conducted to review the current evidence. Thirteen studies were included in the review and these studies assessed a range of stewardship interventions and outcome measures. Overall, ASPs reduced the rates of antibiotic prescription, increased the prescription of narrow-spectrum antibiotics, and shortened the duration of antibiotic therapy. Multimodal interventions that were education-based and those that used RRP testing were found to be the most effective. Whilst we found strong evidence that ASPs are effective in reducing antibiotic prescribing, further studies are required to assess whether they translate to equivalent clinical outcomes.

Antipseudomonal Versus Narrow-Spectrum Agents for the Treatment of Community-Onset Intra-abdominal Infections.

BackgroundAntipseudomonal antibiotics are often used to treat community-acquired intra-abdominal infections (CA-IAIs) despite common causative pathogens being susceptible to more narrow-spectrum agents. The purpose of this study was to compare treatment-associated complications in adult patients treated for CA-IAI with antipseudomonal versus narrow-spectrum regimens.MethodsThis retrospective cohort study included patients >18 years admitted for CA-IAI treated with antibiotics. The primary objective of this study was to compare 90-day treatment-associated complications between patients treated empirically with antipseudomonal versus narrow-spectrum regimens. Secondary objectives were to compare infection and treatment characteristics along with patient outcomes. Subgroup analyses were planned to compare outcomes of patients with low-risk and high-risk CA-IAIs and patients requiring surgical intervention versus medically managed.ResultsA total of 350 patients were included: antipseudomonal, n=204; narrow spectrum, n=146. There were no differences in 90-day treatment-associated complications between groups (antipseudomonal 15.1% vs narrow spectrum 11.3%, P=.296). In addition, no differences were observed in hospital length of stay, 90-day readmission, Clostridiodes difficile, or mortality. In multivariate logistic regression, treatment with a narrow-spectrum regimen (odds ratio [OR], 0.75; 95% confidence interval, 0.39–1.45) was not independently associated with the primary outcome. No differences were observed in 90-day treatment-associated complications for (1) patients with low-risk (antipseudomonal 15% vs narrow spectrum 9.6%, P=.154) or high-risk CA-IAI (antipseudomonal 15.8% vs narrow spectrum 22.2%, P=.588) or (2) those who were surgically (antipseudomonal 8.5% vs narrow spectrum 9.2%, P=.877) or medically managed (antipseudomonal 23.1 vs narrow spectrum 14.5, P=.178).ConclusionsTreatment-associated complications were similar among patients treated with antipseudomonal and narrow-spectrum antibiotics. Antipseudomonal therapy is likely unnecessary for most patients with CA-IAI.

The Tension Between Pragmatism and Rigor in Choosing Wisely.

The Tension Between Pragmatism and Rigor in Choosing Wisely.

A 5-Year Prospective Study on Effect of Antimicrobial Surgical Prophylaxis in the Department of General Surgery

Background: Antibiotic-resistant infections have elevated rates of morbidity and mortality, and antibiotic exposure is a significant trigger factor for drug resistance growth. If surgical antibiotic prophylaxis (SAP) increases risk for antibiotic-resistant infections, it may cause significant harm even if it decreases overall infection rates. The present study is planned to study the effect of antimicrobial surgical prophylaxis in the department of general surgery. Materials and Methods: This prospective study included young age people to old age people who underwent elective surgical procedures. The study was carried for 5 successive years from 2016 to 2020. Surgeries from multiple disciplines were included if SAP was considered discretionary by current guidelines. Results: According to the observations, the antibiotics were administered in all the surgical interventions and most of the pre-operatively antibiotics were administered by IV route. Graph showcases a gradual increase in antibiotic misuse both before and during the surgery. In the year 2016, the antibiotic usage in surgical prophylaxis was observed to be an average of 65.89%. This value was found to be progressively increasing in the successive years. By the year of 2020, the average hiked to the value of 97.11%. This is conclusive of the decreasing misuse of antibiotics with years. Especially the recent times reaching the maximum peak, as appreciated in the graph. This could be attributed as one of the major factors in development of resistance towards various microorganisms that has been managed. Conclusion: Surgical antibiotic prophylaxis is an important treatment technique for preventing postoperative infections, if the right antibiotics are administered at the right moment, for the right length of time, and for the right surgical procedures. It is crucial to use a narrow-spectrum antibiotic that is safe for the surgical venue. The expense of specific antibiotics and the endemicity of multi-resistant bacteria in specific units or clinics are also subject to periodic modification, so hospital surgical antibiotic prophylaxis procedures should be checked on a regular basis.

Impact of Cefazolin Shortage on Clinical Outcomes of Adult Patients with Bacteremia Caused by Methicillin-Susceptible Staphylococcus aureus in a Tertiary Care University Hospital.

Cefazolin is an essential antibiotic used for treating bacteremia; in particular, it is recommended as a first-line agent for infections caused by methicillin-susceptible Staphylococcus aureus (MSSA). In March 2019, problems with a major antibiotic supplier caused a critical shortage of cefazolin in Japan; however, the impact of the cefazolin shortage on clinical outcomes remains unknown. This study aimed to evaluate the effect of the cefazolin shortage in patients with MSSA bacteremia. Data from 75 patients were compared between the pre-shortage (March 2018–January 2019, n = 39) and post-shortage (March 2019–January 2020, n = 36) periods. There were no significant differences in the demographic characteristics between the two groups, and the cefazolin shortage did not worsen clinical outcomes such as adverse drug reactions, treatment failure, and 30-day mortality. In the post-shortage group, ampicillin/sulbactam and benzylpenicillin were more frequently administered as alternative antibiotics for empirical and definitive therapy (10% vs. 31%, p = 0.042; 0% vs. 19%, p = 0.004, respectively). Multivariate analysis revealed that the broad-spectrum antibiotics for definitive therapy, such as antipseudomonal penicillin, were associated with treatment failure in patients with MSSA bacteremia (OR = 17, p = 0.003). Hence, narrow-spectrum antibiotics should be prescribed for MSSA bacteremia as alternatives during a cefazolin shortage.

Targeted Delivery of Narrow-Spectrum Protein Antibiotics to the Lower Gastrointestinal Tract in a Murine Model of Escherichia coli Colonization.

Bacteriocins are narrow-spectrum protein antibiotics that could potentially be used to engineer the human gut microbiota. However, technologies for targeted delivery of proteins to the lower gastrointestinal (GI) tract in preclinical animal models are currently lacking. In this work, we have developed methods for the microencapsulation of Escherichia coli targeting bacteriocins, colicin E9 and Ia, in a pH responsive formulation to allow their targeted delivery and controlled release in an in vivo murine model of E. coli colonization. Membrane emulsification was used to produce a water-in-oil emulsion with the water-soluble polymer subsequently cross-linked to produce hydrogel microcapsules. The microcapsule fabrication process allowed control of the size of the drug delivery system and a near 100% yield of the encapsulated therapeutic cargo. pH-triggered release of the encapsulated colicins was achieved using a widely available pH-responsive anionic copolymer in combination with alginate biopolymers. In vivo experiments using a murine E. coli intestinal colonization model demonstrated that oral delivery of the encapsulated colicins resulted in a significant decrease in intestinal colonization and reduction in E. coli shedding in the feces of the animals. Employing controlled release drug delivery systems such as that described here is essential to enable delivery of new protein therapeutics or other biological interventions for testing within small animal models of infection. Such approaches may have considerable value for the future development of strategies to engineer the human gut microbiota, which is central to health and disease.