Duration Of Antimicrobial Therapy Research Articles

Efficacy of empirical Ciprofloxacin or Cefixime plus Metronidazole therapy for the treatment of liver abscess: a randomized control clinical trial

Liver abscess is a potentially life-threatening medical emergency. Prompt empirical antimicrobial with or without percutaneous aspiration or drainage is therapeutic. The rational for using empirical intravenous broad-spectrum antimicrobials upfront instead of oral Fluoroquinolone or Cephalosporin is contentious. In this double blind randomized control clinical trial 69 participants received Ciprofloxacin (500 mg q 12 hourly) and 71 participants received Cefixime (200 mg q 12 hourly) orally for 2 weeks. Both the group received oral Metronidazole (800 mg q 8 hourly) for 2 weeks and percutaneous drainage or aspiration of the abscess was done as per indication and followed-up for 8 weeks. Out of 140 participants, 89.3% (N = 125) achieved clinical cure, 59 (85.5%) in Ciprofloxacin group and 66 (93%) in Cefixime group (p = 0.154). Mean duration of antimicrobial therapy was 16.2 ± 4.3 days, 15.1 ± 4.5 days in Ciprofloxacin group and 16.0 ± 4.2 days in Cefixime group (p = 0.223). Total 15 (10.7%) participants had treatment failure, 10 (14.5%) in Ciprofloxacin group and 5 (7.0%) in Cefixime group (p = 0.154). The most common reason for treatment failure was need of prolong (> 4 weeks) antimicrobial therapy due to persistent hepatic collection requiring drainage, which was significantly (p = 0.036) higher in Ciprofloxacin (14.5%, N = 10) group, compared to the Cefixime (4.2%, N = 3) group. In conclusion, both, the Ciprofloxacin or Cefixime plus Metronidazole for duration of 2–3 weeks were efficacious as empirical oral antimicrobial regimen along with prompt percutaneous drainage or aspiration for the treatment of uncomplicated liver abscess with similar efficacy. Oral Cefixime was better than Ciprofloxacin in term of lesser chance of treatment failure due to persistent collection which is required to be investigated further in larger clinical trial.Trial registration: clinicaltrials.gov PRS ID: NCT03969758, 31/05/2019.

Implementation of a quality improvement strategy to optimise the management of community acquired pneumonia in a rural health setting.

In Australia, inappropriate prescribing of antimicrobials is higher in rural and regional areas than in major city hospitals. Inappropriate prescribing is defined as the prescription of antimicrobial agents that do not adhere to guidelines in terms of type of antimicrobial chosen, dose and/or duration or are deemed unnecessary. A review of antimicrobial prescribing in a Queensland rural Hospital and Health Service (HHS) identified that respiratory infections were an area for potential improvement. The study was performed in a rural HHS in Queensland. Appropriateness of antimicrobial prescribing for baseline and post-implementation phases of the study was evaluated according to Therapeutic Guidelines: antibiotic recommendations for community acquired pneumonia (CAP). Quality improvement strategy to implement a multifaceted package of interventions for CAP. Post-implementation, overall appropriateness of antimicrobial prescribing improved and there was a decrease in duration of antimicrobial therapy. A quality improvement strategy to implement a multifaceted package of interventions for CAP has shown to be acceptable and effective in improving the antimicrobial prescribing in a rural setting. Our findings highlight the importance of utilising a multifaceted package of interventions which can be tailored to the prescribers and the patients at hand. It is also valuable to engage with local clinicians to promote the optimal management of common infections in the rural setting.

Short versus prolonged duration of therapy for Pseudomonas aeruginosa bacteraemia: a systematic review and meta-analysis

The optimal duration of therapy for Pseudomonas aeruginosa bloodstream infection (PSA-BSI) is unknown, with prolonged therapy frequently favored due to severity of infection, patient complexity, risk of multi-drug resistance, and high mortality. We therefore conducted a systematic review and meta-analysis of studies with head-to-head comparison of short versus prolonged therapy for PSA-BSI. A comprehensive search including Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, and Scopus was performed. We pooled risk ratios (RR) using DerSimonian-Laird random effects model and performed subgroup analysis of outcomes including all-cause mortality, recurrent infection, and composite of these outcomes among patients receiving short versus prolonged therapy for PSA-BSI. Heterogeneity was assessed by the I2-index. Risk of bias for cohort studies was assessed using ROBINS-I tool. From 908 identified studies, 6 were included in the systematic review and 5 studies with head-to-head comparison of treatment duration were assessed in the meta-analysis, totaling 1746 patients. No significant difference in propensity score-weighted composite outcome (30-day all-cause mortality or recurrent infection) was noted between patients receiving short or prolonged therapy, with a pooled RR of 0.80 (95% CI 0.51-1.25, p = 0.32; I2 = 0%). Additionally, duration of therapy did not impact individual outcomes of 30-day all-cause mortality or recurrent/persistent infection. Our meta-analysis demonstrated that short duration of antimicrobial therapy may have similar efficacy as prolonged treatment for PSA-BSI. Future randomized trials will be necessary to definitively determine optimal management of PSA bacteremia. [Trial registration: PROSPERO ID: CRD42023406868].

Outcome of dogs diagnosed with concurrent intrahepatic portosystemic shunts and vertebral lesions: six cases (2016-2022).

To describe the clinical outcome of dogs diagnosed with concurrent discospondylitis/vertebral physitis and congenital intrahepatic portosystemic shunts. Medical records from two academic institutions were searched for dogs diagnosed with discospondylitis and/or vertebral physitis, and a concurrent intrahepatic portosystemic shunt. Dogs were excluded if they did not undergo attenuation of their shunt, did not have a single congenital intrahepatic shunt and did not have at least 90 days of follow-up. Six dogs fittedmet the inclusion criteria and were included in the study. Discospondylitis alone was diagnosed in four dogs, vertebral physitis alone in one dog and both discospondylitis and vertebral physitis in one dog. Three dogs had a right divisional intrahepatic portosystemic shunt, and three dogs had a left divisional intrahepatic portosystemic shunt. Median duration of antimicrobial therapy was 112 days (range 14 to 240 days). Clinical resolution of discospondylitis and vertebral physitis was noted in all dogs. Endovascular attenuation was performed in all dogs a median of 82 days after presentation (range 1 to 317 days). No perioperative or postoperative complications occurred. All dogs were alive at the last available follow-up a median of 513 days after presentation (range 224 to 1504 days) and free of clinical signs associated with discospondylitis or vertebral physitis, as well as their portosystemic shunt. Dogs with intrahepatic portosystemic shunts may concurrently develop discospondylitis and vertebral physitis. With antimicrobial therapy and endovascular embolisation of their portosystemic shunt, all dogs in this study had a good outcome with clinical resolution of both disease processes. However, long-term follow-up was not obtained in all cases.

Reinfection Rates Following Cardiovascular Implantable Electronic Device Reimplementation Post-device Primary Infection

Cardiovascular implantable electronic device (CIED) infections have become an increasing problem around the world, affecting one in 20 patients within 3 years of device implementation. Prevention of reinfection following CIED reimplantation is a prominent challenge. One of the most difficult aspects of managing CIED infections is the complexities of their diagnosis: with the complexities of many infections, timely and correct diagnosis becomes complicated, frequently causing delays in commencing proper therapy, and worsening disease severity. As patients receiving CIED therapy are now older, and possess significant comorbidities, they are at a higher risk of infection. The American Heart Association (AHA) has issued a statement to educate clinicians about CIED infections, and the required care for those with suspected or diagnosed infections. To prevent an infection from spreading, it is important to isolate the causative pathogen and perform testing for susceptibility, which is required for crucial choices, including routes and duration of antimicrobial therapy. This review aims to serve as a valuable resource for healthcare professionals, by synthesising current knowledge and best practices; and providing insights into preventive measures, diagnostic challenges, therapeutic strategies, and evidence-based approaches to diagnose and improve the management of CIED infections in an ageing and medically complex patient population.

When to Stop Antibiotics in the Critically Ill?

Over the past century, antibiotic usage has skyrocketed in the treatment of critically ill patients. There have been increasing calls to establish guidelines for appropriate treatment and durations of antibiosis. Antibiotic treatment, even when appropriately tailored to the patient and infection, is not without cost. Short term risks-hepatic/renal dysfunction, intermediate effects-concomitant superinfections, and long-term risks-potentiating antimicrobial resistance (AMR), are all possible consequences of antimicrobial administration. These risks are increased by longer periods of treatment and unnecessarily broad treatment courses. Recently, the literature has focused on multiple strategies to determine the appropriate duration of antimicrobial therapy. Further, there is a clinical shift to multi-modal approaches to determine the most suitable timepoint at which to end an antibiotic course. An approach utilising biomarker assays and an inter-disciplinary team of pharmacists, nurses, physicians, and microbiologists appears to be the way forward to develop sound clinical decision-making surrounding antibiotic treatment.

Evaluating the utility of procalcitonin and a clinical decision support tool to determine duration of antimicrobial therapy for respiratory tract infections.

In an effort to expedite the publication of articles, AJHP is posting manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time. Procalcitonin (PCT) levels may play a role in decreasing the duration of antimicrobial therapy in institutions that have long durations of therapy for management of community-acquired pneumonia. We assessed the impact of the combination of pharmacist stewardship interventions assisted by a clinical decision support (CDS) tool and PCT assessment on the antimicrobial days of therapy (DOT) prescribed for respiratory tract infections (RTIs). We conducted a quasi-experimental study in which patients in the preintervention group were admitted between April and June 2021 and patients in the intervention group were admitted between April and June 2022. In the intervention phase, a CDS tool was utilized to alert clinical pharmacists when patients met specific criteria. This alert was programmed to activate for individual patients when a reported PCT level was less than 0.25ng/mL and on antimicrobials prescribed for an RTI as indicated by providers in the electronic health record. Stewardship interventions were made by pharmacists via prospective audit and feedback. The primary endpoint was inpatient antimicrobial DOT for RTIs. There were 90 patients in the preintervention group and 104 patients in the intervention group. Although baseline characteristics were not well matched between the groups, favoring the preintervention group, the median DOT was lower in the intervention group at 3 days (interquartile range [IQR], 2-4 days), compared to 4 days (IQR, 2.8-5 days) in the preintervention group (P = 0.001). The results of our study demonstrate the utility of pharmacist interventions coupled with CDS and PCT in reducing antimicrobial DOT prescribed for RTIs. Antimicrobial stewardship programs may benefit from implementing a PCT bundle.

Antimicrobial therapy outcomes in acute cholangitis: Hilar multiple obstructions versus single hilar and common bile duct obstructions.

The appropriate duration of antimicrobial therapy for acute cholangitis (AC) arising from multiple hilar biliary obstructions as opposed to simple obstruction in the extrahepatic bile duct has not been established. This study assessed the efficacy of the duration of antimicrobial treatments in the Tokyo Guidelines 2018 for AC based on the cause and site of obstruction. This single-center retrospective study involved patients with AC who underwent successful biliary drainage and completed a 7-day or shorter antimicrobial treatment. Patients were categorized into three groups: Group 1, bile duct stone or benign obstruction; Group 2, simple biliary obstruction due to malignancy; and Group 3, multiple hilar biliary obstruction due to malignancy. The primary outcome was clinical cure rate, and the secondary outcomes were 3-month recurrence rate and length of hospital stay. A total of 373 patients were selected. Patients in Group 3 were younger or had Charlson Comorbidity Index ≥4, and had fewer positive blood cultures. In Group 3, the clinical cure rate (87.1%) and 3-month recurrence rate (32.3%) were less favorable than those in the other groups. In Group 1, the clinical cure rate was significantly higher (98.1%, P = 0.02) with a much lower 3-month recurrence rate of only 3.4% (P < 0.001) than that in the other groups. The median hospital stay for all groups was 7 days. This study suggests that the outcomes in Group 3 may be worse than those in Groups 1 or 2, regardless of the duration of the antibiotic treatment.

Shorter versus longer duration of antimicrobial therapy for early Lyme disease: A systematic review and meta-analysis

BackgroundAntibiotic therapy for patients with early Lyme disease is necessary to prevent later-stage Lyme disease complications. This systematic review and meta-analysis compares shorter versus longer antibiotic regimens in treating early Lyme disease. MethodsA systematic search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted up to November 2023. We examined treatment failure, complete response, and photosensitivity. Short vs. long therapy was defined as ≤10 days vs. >10 days. Subgroup analyses included antibiotic type and varying treatment durations. Analysis utilized RStudio 4.1.2. PROSPERO registration: CRD42023423876. ResultsSeven studies, encompassing 1,462 patients, were analyzed. No significant differences in treatment failure, 12-month complete response, final visit complete response were found between short and long durations of antibiotic therapy. Subgroup and sensitivity analyses corroborated these findings. ConclusionShorter and longer antibiotic regimens for early Lyme disease show similar efficacy, highlighting the potential of ≤10-day courses, as effective treatment options.

Association of short-course antimicrobial therapy and bacterial resistance in acute cholangitis: Retrospective cohort study.

Background and study aims Although the number of resistant bacteria tends to increase with prolonged antimicrobial therapy, no studies have examined the relationship between the duration of antimicrobial therapy and increase in the number of resistant bacteria in acute cholangitis. We hypothesized that the short-term administration of antimicrobial agents in acute cholangitis would suppress bacterial resistance. Patients and methods This was a single-center, retrospective, observational study of patients with acute cholangitis admitted between January 2018 and June 2020 who met the following criteria: successful biliary drainage, positive blood or bile cultures, bacteria identified from cultures sensitive to antimicrobials, and subsequent cholangitis recurrence by January 2022. The patients were divided into two groups: those whose causative organisms at the time of recurrence became resistant to the antimicrobial agents used at the time of initial admission (resistant group) and those who remained susceptible (susceptible group). Multivariate analysis was used to examine risk factors associated with the development of resistant pathogens. Multivariate analysis investigated antibiotics used with the length of 3 days or shorter after endoscopic retrograde cholangiopancreatography (ERCP) and previously reported risk factors for the development of bacterial resistance. Results In total, 89 eligible patients were included in this study. There were no significant differences in patient background or ERCP findings between the groups. The use of antibiotics, completed within 3 days after ERCP, was associated with a lower risk of developing bacterial resistance (odds ratio, 0.17; 95% confidence interval, 0.04-0.65; P =0.01). Conclusions In acute cholangitis, the administration of antimicrobials within 3 days of ERCP may suppress the development of resistant bacteria.

Evaluation of long-term pharmacist-led prospective audit and feedback in antimicrobial stewardship: An 8-year study

Limited research has evaluated the long-term outcomes of prospective audit and feedback (PAF) led by pharmacists. We assessed pharmacist-led PAF processes and outcome measures over 8 years. This study was conducted at a single public hospital in Japan. Between 2014 and 2021, pharmacists conducted weekday PAFs for hospitalized patients and annually evaluated the process and outcome measures. The endpoints included detection of drug-resistant bacteria, drug susceptibility rates, duration of antimicrobial therapy, and proportion of long-term administration. Among inpatients, methicillin-resistant Staphylococcus aureus significantly decreased from 50.9% in 2014 to 32.8% in 2021 (P<.001). The susceptibility rate of Pseudomonas aeruginosa to meropenem significantly increased from 91.2% in 2014 to 94.4% in 2021 (P<.001) and levofloxacin increased from 84.9% in 2014 to 89.3% in 2021 (P<.001). Antimicrobial therapy duration did not differ significantly between 2014 and 2016, but decreased significantly from 2017 onwards (P<.001), except in 2018. The number of patients receiving intravenous antimicrobials for >10 days decreased significantly between 2014 and 2021 (P<.001). Long-term continuous PAF interventions by pharmacists contribute to improving and maintaining process and outcome indicators and prevent the spread of drug-resistant bacteria.

2408. Is Shorter Antibiotic Treatment Feasible in Patients with Cardiac Implantable Electronic Devices (CIED) Infections? Impact of Treatment Duration on 6-Month Recurrence and Mortality

Abstract Background Aim of this study is to compare the 6-month outcomes (recurrence and mortality) of patients with cardiac implantable electronic device (CIED) infections treated with short (SHORT, &amp;lt;14 days) or long (LONG, &amp;gt;14 days) duration of antimicrobial therapy after device removal. Methods Retrospective cohort study of patients hospitalized at IRCCS San Raffaele Hospital (Milan, Italy) from June 2011 to June 2021, who underwent device removal for CIED infection. Patients with pocket and lead infections were included, while valve endocarditis and Staphylococcus aureus infection were excluded. The characteristics of patients in the SHORT and LONG groups were compared using the chi-square test for categorical variables and the Mann-Whitney U-test for continuous variables. A propensity score (PS) was calculated using a logistic regression that considered duration of therapy as the dependent variable; the association between patients’ characteristics and outcomes was evaluated with logistic regression analysis. Results The characteristics of the 150 included patients are described in table 1, the microbial etiology in table 2. Patients in the SHORT compared to the LONG group were older (75 [65-80] vs 69 [62-77], p-value=0.047), had a higher Charlson comorbidity index (5 [3-6] vs 4 [3-5], p-value=0.021), had less frequent isolation of coagulase-negative staphylococci (CoNS; 46.7% vs 68.9%, p-value=0.006), and an unknown etiology (36.7% vs 13.3%, p-value=0.001). Moreover, the duration of antimicrobial treatment after device removal was shorter (13 [9-14] vs 20 [16-29] days, p-value&amp;lt; 0.001). At 6 months, recurrence and mortality were not significantly different between the SHORT and the LONG group (recurrences: 2 [3.7%] vs 5 [6.7%], p-value=0.464; mortality: 2 [3.7%] vs 3 [4.0%], p-value=0.931), At logistic regression analysis (table 3 and table 4) adjusted for PS, treatment duration was not significantly associated with either recurrence (odds ratio [OR] 0.524; 95% confidence interval [95%CI] 0.084-3.263) or mortality (OR 1.402; 95%CI 0.185-10.635). Conclusion A shorter duration of antimicrobial treatment after device removal may be an effective approach for treating patients with CIED infections. Disclosures Antonella Castagna, MD, Bristol-Myers Squibb: consultancy payments and speaking fees|Gilead: consultancy payments and speaking fees|Janssen-Cilag: consultancy payments and speaking fees|Merck Sharp &amp; Dohme: consultancy payments and speaking fees|ViiV Healthcare: consultancy payments and speaking fees

Risk factors for positive follow-up blood cultures in Gram-negative bacteremia among immunocompromised patients with neutropenia.

Gram-negative bacillary bloodstream infection (GN-BSI) is a frequent clinical challenge among immunocompromised hosts and is associated with a high mortality. The utility of follow-up blood cultures (FUBCs) for GN-BSI in this population, particularly in the setting of neutropenia, is poorly defined. We conducted a single-center, retrospective cohort study between the period of July 2018 and April 2022 to investigate the utility of FUBCs and delineate risk factors for positive cultures among neutropenic patients with monomicrobial GN-BSI. Univariate logistic regression was performed to assess risk factors associated with positive FUBCs. Of 206 patients, 98% had FUBCs performed, and 9% were positive. Risk factors for positive FUBCs included multidrug-resistant GN infection (OR 3.26; 95% confidence interval [CI] 1.22-8.72) and vascular catheter source (OR 4.82; CI 1.76-13.17). Among patients lacking these risk factors, the prevalence of positive FUBCs was low (2.8%) and the negative predictive value was 92%. Those with positive and negative FUBCs had similar rates of all-cause mortality (16.7% vs. 16.6%; p=.942) and microbiologic relapse (11.1% vs. 6.0%; p=.401) within 90-days of treatment completion. However, positive FUBCs were associated with prolonged hospitalization and longer duration of antimicrobial therapy. Positive FUBCs were infrequent in neutropenic patients with GN-BSI, and their occurrence did not significantly impact mortality or microbiologic relapse. Risk factors for positive FUBCs included multidrug resistant Gram-negative infection and vascular catheter source. Prospective studies will be necessary to elucidate the benefits and risks of FUBCs when managing GN-BSI in patients with underlying immune compromise.

Prolonged prothrombin time in a rare case of vitamin K deficiency: a case report and a narrative review

Prolonged prothrombin time increases the risk of bleeding complications in proportion to prolongation severity. We reported the case of a 72-year-old woman with a recent hospitalization for methicillin-susceptible Staphylococcus aureus endocarditis complicated by spondylodiscitis who developed a severe prolongation of clotting time during treatment with cefazolin due to a vitamin K deficiency. Cefazolin is a first-generation cephalosporin active against gram-positive bacteria. Like other cephalosporins, it is potentially able to inhibit the enzymes involved in recycling vitamin K metabolites, leading to a fall in gamma-carboxylation of vitamin K-dependent clotting factors. Clinicians should be aware of the necessity of regular monitoring of clotting times for the duration of antimicrobial therapy, especially in those patients with several risk factors for a poor vitamin K nutritional status. Prompt detection of vitamin K deficiency should be recognized and adequately supplemented.

Short-Course Versus Prolonged-Course Antimicrobial Therapy in Adults With Catheter-Related Septic Thrombosis: A Propensity-Weighted Retrospective Study

Abstract Background Optimal duration of antimicrobial therapy (AT) for catheter-related septic deep venous thrombosis (DVT) is unknown. We aimed to compare the outcomes of patients receiving short-course AT (≤21 days) versus prolonged-course AT (&amp;gt;21 days). Methods This was a monocentric retrospective study comparing adults with catheter-related septic DVT from 2015 to 2020 treated with short- or prolonged-course AT. A propensity score–weighted analysis was used to mitigate potential bias. The primary outcome was a composite of all-cause mortality or recurrent bloodstream infection 30 days after AT discontinuation. Results Of 172 patients with catheter-related septic DVT, 104 were treated with prolonged-course AT and 68 with short-course AT. In the propensity score analysis, we found no significant difference in 30-day all-cause mortality or relapse between the 2 groups (inverse probability of treatment weighted hazard ratio [wHR], 2.16 [95% confidence interval {CI}, .68–6.88]; P = .192). No differences in 90-day all-cause mortality and 90-day relapse were observed between the treatment groups (wHR, 1.01 [95% CI, .49–2.05], P = .987 and 1.13 [95% CI, .08–15.62], P = .928, respectively). Conclusions A 21-day AT could be an effective and safe option to treat catheter-related septic DVT. Further randomized studies are needed to establish the optimal duration of AT for patients with catheter-related septic DVT.

Trimethoprim/Sulfamethoxazole vs Minocycline for the Treatment of Nonurinary Monomicrobial Stenotrophomonas maltophilia Infections in Hospitalized Patients.

Stenotrophomonas maltophilia is an opportunistic, gram-negative bacillus with few therapeutic options due to a high level of intrinsic resistance. Trimethoprim/sulfamethoxazole (SXT) is recommended as the first-line treatment; however, minocycline (MIN) has been shown to have similar clinical outcomes in treating S. maltophilia and addresses concern for increasing resistance to SXT. The objective of this study is to evaluate the efficacy and safety outcomes of nonurinary, monomicrobial infections due to S. maltophilia in hospitalized patients treated with MIN or SXT. This was a retrospective study of hospitalized adult patients receiving MIN or SXT for nonurinary monomicrobial S. maltophilia infection from April 1, 2018 to March 31, 2020. The primary outcome was clinical disposition classified as rates of clinical failure, clinical improvement, or clinical success. Eighty-two patients (88.2%) received MIN and 11 patients (11.8%) received SXT initially. Clinical failure occurred in 16 (19.5%) patients in the MIN group and in 4 (36.4%) patients in the SXT group (P = 0.242). Clinical improvement occurred in 11 (13.4%) patients in the MIN group and in 1 (9.1%) patient in the SXT group (P = 1.0). Clinical success occurred in 55 (67.1%) patients in the MIN group and in 6 (54.5%) patients in the SXT group (P = 0.503). Total duration of antimicrobial therapy (P = 0.3198), in-hospital mortality (P = 1.0), hospital length of stay (P = 0.9668), intensive care unit (ICU) length of stay (P = 0.1384), and 30-day readmission (P = 0.686) were similar between groups. Rates of clinical failure, clinical improvement, or clinical success were similar between MIN and SXT for nonurinary monomicrobial S. maltophilia infections.

Management of Pyogenic Liver Abscesses: Contemporary Strategies and Challenges.

Pyogenic liver abscesses (PLAs) are a suppurative infection of the hepatic parenchyma responsible for significant morbidity and mortality. PLAs are categorized into a variety of mechanisms: (1) via the portal vein, (2) through the biliary tract, (3) via the hepatic artery, (4) from trauma, (5) contiguously via direct extension, and (6) cryptogenically. The pathogenesis of PLA, which informs treatment, can often be discerned based on host factors, clinical presentation, and causative microorganisms. The Streptococcus anginosus group, hypervirulent Klebsiella pneumoniae , and multidrug-resistant gram-negative pathogens have emerged as microbiologically challenging organisms to treat. The identification of hypervirulent K. pneumoniae should prompt for assessment for metastatic spread and consideration of prolonged antimicrobial treatment. Abdominal imaging is indispensable in characterizing PLAs and facilitating source control interventions. Source control remains the most critical aspect of PLA management, followed by antimicrobial therapy. Empiric antibiotics for PLAs are informed by the suspected etiology of PLA formation. Duration of antimicrobial therapy is individualized and dependent on multiple components, including the success of achieving source control, host factors, mechanism of PLA development, and the illness course of the individual-factoring in clinical, biochemical, and radiographic parameters.

Effects of antimicrobial therapy duration and class on risk of antimicrobial-resistant Gram-negative bacillus bloodstream infection in patients with AML.

Antimicrobial-resistant Gram-negative bacilli (ARGNB) bloodstream infection (BSI) has been associated with prior antibiotic exposure among hematologic malignancy patients. The relationships between days of therapy (DOT), antimicrobial class, and ARGNB BSI risk are poorly understood. This is a single-center, case-control study of acute myeloid leukemia (AML) patients including 115 cases with ARGNB BSI and 230 matched controls with non-ARGNB BSI between January 1, 2007 and December 31, 2018. Fixed- and mixed-effects logistic regression was used to examine relationships between antibiotic DOT and risk of ARGNB BSI. Admission to an intensive care unit (ICU) within 7 days, 30-day mortality, and Pitt Bacteremia Score (PBS) were secondary outcomes. Prior isolation of a antimicrobial-resistant organism (ARO) (OR 4.45 95% CI 1.46, 13.54), surgery within 90 days (OR 3.71, 95% CI 1.57, 8.73), aminoglycoside DOT (OR 1.14, 95% CI 1.05, 1.23), cefepime DOT (OR 1.09, 95% CI 1.05, 1.13), and carbapenem DOT (OR 1.10, 95% CI 1.05, 1.16) were associated with increased odds of ARGNB BSI. Days since last antibiotic administration (OR 0.98, 95% CI 0.97, 0.99) and inpatient days within 90 days (OR 0.95, 95% CI 0.93, 0.98) showed reduced odds of ARGNB BSI. Total antimicrobial DOT regardless of class was not associated with ARGNB BSI. ARGNB BSI was associated with increased 30-day mortality (OR 2.86, 95% CI 1.57, 5.22) CONCLUSIONS: Among AML patients with GNB BSI, greater DOT of aminoglycosides, cefepime, and carbapenems in the 90 days prior to BSI were associated with increased odds of ARGNB BSI.

The clinical impact of early detection of ESBL-producing Enterobacterales with PCR-based blood culture assays

Starting January 4, 2021, our health system core microbiology laboratory changed blood culture identification (BCID) platforms to ePlex BCID from BioFire BCID1 with the additional capability to detect the blaCTX-M-Type gene of ESBL-producing organisms. Clinical outcomes of ESBL bloodstream infections (BSI) after implementing ePlex BCID were unknown. Patients with ESBL BSI were compared pre and postimplementation of ePlex BCID in this 11-hospital retrospective analysis (BioFire BCID1 in 2019 vs ePlex BCID in 2021). The primary outcome was time from the Gram stain result to escalation to a carbapenem. Secondary outcomes included in-hospital mortality, 30-day readmission rate, length of stay (LOS), and the duration of antimicrobial therapy. A total of 275 patients were analyzed. The median time of Gram stain result to escalation to carbapenem was reduced from 44.5hours with BioFire BCID1 to 7.9hours with ePlex BCID (P<.001). There were no significant differences in mortality, 30-day readmission, or LOS. The duration of antimicrobial therapy for ESBL BSI was lower in the ePlex BCID group (from 14.4 days to 12.7 days, P=.014). Timely detection of the blaCTX-M-Type gene by BCID provides valuable information for the early initiation of appropriate and effective antimicrobial therapy. Although it was not associated with lower mortality, 30-day readmission, or LOS, it may have benefits such as decreasing antimicrobial exposure to patients.

Management and outcomes of heart transplant candidates with bloodstream infection on temporary mechanical circulatory support

The outcomes and management of bloodstream infection (BSI) in patients on temporary mechanical circulatory support (TMCS) awaiting heart transplant (HT) are poorly understood. We present outcomes of patients on TMCS with BSI (TMCS-I) relative to matched uninfected patients (TMCS-U) and discuss their management. Between 1/1/2013-4/30/2023, N=136 patients were bridged to transplant with TMCS at Emory Transplant Center. Twenty-one (15.4%) were TMCS-I. Two (9.5%) had infective endocarditis. Median duration of antimicrobial treatment was 24 days (IQR 28.3). All TMCS-I were re-activated for transplant within 48-72 hours of negative blood cultures. None developed recurrent BSI. Post-transplant survival did not differ between TMCS-I and TMCS-U (P=0.38). HT for TMCS-I may be safe as soon as blood cultures clear. Duration of antimicrobial therapy is individualized and depends on the organism, duration of bacteremia, presence of endocarditis, and timing of HT. Additional research is needed to determine optimal duration of treatment.