Staphylococcus Aureus Bacteremia Research Articles

Adherence to and clinical utility of "quality indicators" for Staphylococcus aureus bacteremia: a retrospective, multicenter study.

We aimed to improve the prognosis, treatment, and management of Staphylococcus aureus bacteremia (SAB) by evaluating the association between adherence to quality indicators (QIs) and clinical outcomes in patients with their clinical outcomes. We retrospectively collected clinical and microbiological data on hospitalized patients with SAB from 14 hospitals (three with > 600, two with 401-600, five with 201-400, and four with ≤ 200 beds) in Japan from January to December 2022. The SAB management quality was evaluated using the SAB-QI score (ranging from 0 to 13 points), which consists of 13 QIs (grouped into five categories) based on previous literature. Of the 4,448 positive blood culture episodes, 289 patients with SAB (6.5%) were enrolled. The SAB-QI scores ranged from 3 to 13, with a median score of 9 points. The SAB-QI score was highest in middle-sized hospitals with 401-600 beds. Adherence to each of the four QI categories (blood culture, echocardiography, source control, and antibiotic treatment) was significantly higher in survived cases than in fatal cases. Kaplan-Meier curves with log-rank tests demonstrated that higher adherence to SAB-QIs indicated a better prognosis. Logistic regression analysis revealed that age, methicillin resistance, multiple comorbidities (≥2), and low SAB-QI score were significantly associated with 30-day mortality in patients with SAB. Our study highlights that greater adherence to the SAB-QIs correlates with improved patient outcomes. Management of patients with SAB should follow these recommended indicators to maintain the quality of care, especially for patients with poor prognosticators.

Low-risk Staphylococcus aureus bacteremia patients do not require routine diagnostic imaging: A multicenter retrospective cohort study.

Risk stratification to categorize patients with Staphylococcus aureus bacteremia (SAB) as low- or high-risk for metastatic infection may direct diagnostic evaluation and enable personalized management. We investigated the frequency of metastatic infections in low-risk SAB patients, their clinical relevance, and whether omission of routine imaging is associated with worse outcomes. We performed a retrospective cohort study in seven Dutch hospitals among adult patients with low-risk SAB, defined as hospital-acquired infection without treatment delay, absence of prosthetic material, short duration of bacteremia, and rapid defervescence. The primary outcome was the proportion of patients whose treatment plan changed due to detected metastatic infections, as evaluated by both the actual therapy administered and by linking a retrospectively adjudicated diagnosis to guideline-recommended treatment. Secondary outcomes were 90-day relapse-free survival, and factors associated with performing of diagnostic imaging. Of 377 patients included, 298 (79%) underwent diagnostic imaging. In 15 of these 298 patients (5.0%) imaging findings during patient admission had been interpreted as metastatic infections that should extend duration of treatment. Using the final adjudicated diagnosis, 4 patients (1.3%) had clinically relevant metastatic infection. In a multilevel multivariable logistic regression analysis, 90-days relapse-free survival was similar between patients without imaging and those who underwent imaging (81.0% versus 83.6%; aOR 0.749 (95% CI 0.373-1.504). Our study advocates risk stratification for the management of patients with SAB. Prerequisites are follow-up blood cultures, bedside ID consultation, along with critically reviewing disease evolution. Using this approach, routine imaging could be omitted in low-risk patients.

Staphylococcus aureus bacteraemia, cardiac implantable electronic device, extraction, and the risk of recurrent infection; a retrospective population-based cohort study

Background Patients with cardiac implantable electronic device (CIED) and Staphylococcus aureus bacteraemia (SAB) are at risk of having CIED infection, pocket infection or endocarditis. To avoid treatment failures, guidelines recommend that the CIED should be extracted in all cases of SAB butrecent studies indicate low extraction rates and low risk of relapse. The aim of the study was to describe a Swedish population-based cohort of patients with CIED and SAB, the rate of extraction, and treatment failure measured as recurrent SAB. Methods Patients identified to have SAB in the Karolinska Laboratory database, serving a population of 1.9 million, from January 2015 through December 2019 were matched to the Swedish ICD and Pacemaker Registry. Patients with CIED and SAB were included. Clinical data were collected from medical records. Results A cohort of 274 patients was identified and 38 patients (14%)had the CIED extracted. Factors associated with extraction were lower age, lower Charlson comorbidity index, shorter time since CIED implantation, and non-nosocomial acquisition, but not mortality. No patient was put on lifelong antibiotic treatment. Sixteen patients (6%) had a recurrent SAB within one year, two in patients subjected to extraction (5%) and 14 in patients not subjected to CIED-extraction (6%). Three of the 14 patients were found to have definite endocarditis during the recurrent episode. Conclusions Despite a low extraction rate, there were few recurrences. We suggest that extraction of the CIED might be omitted if pocket infection, changes on the CIED, or definite endocarditis are not detected.

Sequential Time to Positivity as a Prognostic Indicator in Staphylococcus aureus Bacteremia.

We aimed to determine the factors associated with sequential blood culture time to positivity (STTP) and validate the previously defined time to positivity (TTP) ratio threshold of 1.5 in predicting adverse disease outcomes and mortality of Staphylococcus aureus bacteremia (SAB). We conducted an observational study of adult patients with SAB. The TTP ratio was calculated by dividing the TTP of the second blood culture by that of the first. Of 186 patients, 69 (37%) were female, with a mean age of 63.6 years. Median TTP was 12 hours (interquartile range [IQR], 10-15 hours) from the initial and 21 hours (17-29) from sequential blood cultures. Methicillin-resistant S aureus (MRSA)-infected patients had significantly shorter STTPs (P < .001) and lower TTP ratios (P < .001) compared to patients with methicillin-susceptible S aureus (MSSA). A significant correlation between initial and STTP was observed in patients with MRSA (r = 0.42, P = .002) but not in those with MSSA. A higher rate of native valve endocarditis (NVE) significantly correlated with a TTP ratio of ≤1.5 (odds ratio, 2.65 [95% confidence interval, 1.3-5.6]; P = .01). The subgroup having an initial TTP <12 hours combined with a TTP ratio ≤1.5 showed the highest prevalence of NVE. The STTP varies based on methicillin susceptibility of S aureus isolate. This study suggests a potential clinical utility of the STTP to identify patients at a higher risk of NVE. However, prospective studies are required to validate these findings.

Rheumatoid arthritis and risk of osteoarticular infection and death following Staphylococcus aureus bacteraemia: A nationwide cohort study.

Osteoarticular infection (OAI) is a feared complication of Staphylococcus aureus bacteraemia (SAB) and is associated with poor outcomes. We aimed to explore risk of OAI and death following SAB in patients with and without rheumatoid arthritis (RA) and to identify risk factors for OAI in patients with RA. Danish nationwide cohort study of all patients with microbiologically verified first-time SAB between 2006-2018. We identified RA, SAB, comorbidities, and RA-related characteristics (e.g. orthopaedic implants, antirheumatic treatment) in national registries including the rheumatology registry DANBIO. We estimated cumulative incidence of OAI and death and adjusted hazard ratios (HRs, multivariate Cox regression). We identified 18 274 patients with SAB (n = 367 with RA). The 90-day cumulative incidence of OAI was 23.1%(95%CI 18.8; 27.6) for patients with RA and 12.5%(12.1; 13.0) for patients without RA (non-RA) (HR 1.93(1.54; 2.41)). For RA patients with orthopaedic implants cumulative incidence was 29.4%(22.9; 36.2) (HR 1.75(1.08; 2.85), and for current users of tumor necrosis factor inhibitors (TNFi) it was 41.9%(27.0; 56.1) (HR 2.27(1.29; 3.98) compared with non-users). All-cause 90-day mortality following SAB was similar in RA (35.4%(30.6; 40.3)) and non-RA (33.9%(33.2; 34.5), HR 1.04(0.87; 1.24)). Following SAB, almost one in four patients with RA contracted OAI corresponding to a doubled risk compared with non-RA. In RA, orthopaedic implants and current TNFi use were associated with approximately doubled OAI risk. One in three died within 90 days in both RA and non-RA. These findings encourage vigilance in RA patients with SAB to avoid treatment delay of OAI.

Staphylococcus aureus Bacteraemia in Patients with Chronic Kidney Disease: Single-Centre Data from Pakistan

Staphylococcus aureus Bacteraemia in Patients with Chronic Kidney Disease: Single-Centre Data from Pakistan

A machine learning-based risk score for prediction of infective endocarditis among patients with Staphylococcus aureus bacteraemia - The SABIER score.

Early risk assessment is needed to stratify Staphylococcus aureus infective endocarditis (SA-IE) risk among Staphylococcus aureus bacteraemia (SAB) patients to guide clinical management. The objective of this study is to develop a novel risk score independent of subjective clinical judgment and can be used early at the time of blood culture positivity. We conducted a retrospective big data analysis from territory-wide electronic data and included hospitalized patients with SAB between 2009 and 2019. We applied a random forest risk scoring model to select variables from an array of parameters, according to the statistical importance of each feature in predicting SA-IE outcome. The data was divided into derivation and validation cohorts. The areas under the curve of the receiver operating characteristic (AUCROC) were determined. We identified 15,741 SAB patients, among them 4.18% had SA-IE. The AUCROC was 0.74 (95%CI 0.70-0.76), with a negative predictive value of 0.980 (95%CI 0.977-0.983). The four most discriminatory features were age, history of infective endocarditis, valvular heart disease, and being community-onset. We developed a novel risk score with good performance as compared to existing scores and can be used at the time of SAB and prior to subjective clinical judgment.

Validation of a new risk stratification system-based management for methicillin-resistant Staphylococcus aureus bacteraemia: analysis of a multicentre prospective study.

Distinguishing between complicated and uncomplicated Staphylococcus aureus bacteraemia (SAB) is therapeutically essential. However, this distinction has limitations in reflecting the heterogeneity of SAB and encouraging targeted diagnostics. Recently, a new risk stratification system for SAB metastatic infection, involving stepwise approaches to diagnosis and treatment, has been suggested. We assessed its applicability in methicillin-resistant SAB (MRSAB) patients. We retrospectively analysed data of a 3-year multicentre, prospective cohort of hospitalised patients with MRSAB. We classified the patients into three risk groups: low, indeterminate, and high, based on the new system and compared between-group management and outcomes. Of 380 patients with MRSAB, 6.3% were classified as low-, 7.6% as indeterminate-, and 86.1% as high-risk for metastatic infection. No metastatic infection occurred in the low-, 6.9% in the indeterminate-, and 19.6% in the high-risk groups (P < 0.001). After an in-depth diagnostic work-up, patients were finally diagnosed as 'without metastatic infection (6.3%)', 'with metastatic infection (17.4%)', and 'uncertain for metastatic infection (76.3%)'. 30-day mortality increased as the severity of diagnosis shifted from 'without metastatic infection' to 'uncertain for metastatic infection' and 'with metastatic infection' (P = 0.09). In multivariable analysis, independent factors associated with metastatic complications were suspicion of endocarditis in transthoracic echocardiography, clinical signs of metastatic infection, Pitt bacteraemia score ≥ 4, and persistent bacteraemia. The new risk stratification system shows promise in predicting metastatic complications and guiding work-up and management of MRSAB. However, reducing the number of cases labelled as 'high-risk' and 'uncertain for metastatic infection' remains an area for improvement.

Bacteriophage therapy for drug-resistant Staphylococcus aureus infections.

Drug-resistant Staphylococcus aureus stands as a prominent pathogen in nosocomial and community-acquired infections, capable of inciting various infections at different sites in patients. This includes Staphylococcus aureus bacteremia (SaB), which exhibits a severe infection frequently associated with significant mortality rate of approximately 25%. In the absence of better alternative therapies, antibiotics is still the main approach for treating infections. However, excessive use of antibiotics has, in turn, led to an increase in antimicrobial resistance. Hence, it is imperative that new strategies are developed to control drug-resistant S. aureus infections. Bacteriophages are viruses with the ability to infect bacteria. Bacteriophages, were used to treat bacterial infections before the advent of antibiotics, but were subsequently replaced by antibiotics due to limited theoretical understanding and inefficient preparation processes at the time. Recently, phages have attracted the attention of many researchers again because of the serious problem of antibiotic resistance. This article provides a comprehensive overview of phage biology, animal models, diverse clinical case treatments, and clinical trials in the context of drug-resistant S. aureus phage therapy. It also assesses the strengths and limitations of phage therapy and outlines the future prospects and research directions. This review is expected to offer valuable insights for researchers engaged in phage-based treatments for drug-resistant S. aureus infections.

Mortality patterns in patients with Staphylococcus aureus bacteremia during the COVID-19 pandemic: Predictors and insights

ObjectivesThis paper aims to determine the Staphylococcus aureus bacteremia (SAB) in-hospital mortality rate and its associated risk factors during the COVID-19 pandemic. MethodsA total of 167 SAB samples were collected between March 2020 and March 2022 at a teaching hospital in Tehran, Iran. The patient's baseline data and antibiograms were collected. The outcome of the study was in-hospital mortality. ResultsThe overall in-hospital mortality rate was 41.9 %, with higher mortality observed in patients over 60 years old (P = 0.032), those with community-acquired Staphylococcus aureus bacteremia (P = 0.010), and those admitted to the ICU (P = 0.016). Antibiotic resistance profiles indicated a higher mortality in resistant S.aureus strains but only significant for ciprofloxacin (P = 0.001), methicillin (P = 0.047), and sulfamethoxazole (P = 0.023). Multivariate analysis identified age, sex, ICU admission, and the source of bacteremia as independent predictors of mortality, while COVID-19 coinfection and resistance to antibiotics were not found to be significant predictors. ConclusionSAB remains a challenging infection that is amplified by the pandemic. Older age and ICU admission are significant mortality predictors. In settings with a high prevalence of MRSA, factors like age, sex, and quality of care outweigh pathogen-related factors such as antibiotic resistance.

The Utility of Risk Factors to Define Complicated Staphylococcus aureus Bacteremia in a Setting With Low Methicillin-Resistant S. aureus Prevalence.

Recommended duration of antibiotic treatment of Staphylococcus aureus bacteremia (SAB) is frequently based on distinguishing uncomplicated and complicated SAB, and several risk factors at the onset of infection have been proposed to define complicated SAB. Predictive values of risk factors for complicated SAB have not been validated, and consequences of their use on antibiotic prescriptions are unknown. In a prospective cohort, patients with SAB were categorized as complicated or uncomplicated through adjudication (reference definition). Associations and predictive values of 9 risk factors were determined, compared with the reference definition, as was accuracy of Infectious Diseases Society of America (IDSA) criteria that include 4 risk factors, and the projected consequences of applying IDSA criteria on antibiotic use. Among 490 patients, 296 (60%) had complicated SAB. In multivariable analysis, persistent bacteremia (odds ratio [OR], 6.8; 95% confidence interval [CI], 3.9-12.0), community acquisition of SAB (OR, 2.9; 95% CI, 1.9-4.7) and presence of prosthetic material (OR, 2.3; 95% CI, 1.5-3.6) were associated with complicated SAB. Presence of any of the 4 risk factors in the IDSA definition of complicated SAB had a positive predictive value of 70.9% (95% CI, 65.5-75.9) and a negative predictive value of 57.5% (95% CI, 49.1-64.8). Compared with the reference, IDSA criteria yielded 24 (5%) false-negative and 90 (18%) false-positive classifications of complicated SAB. Median duration of antibiotic treatment of these 90 patients was 16 days (interquartile range, 14-19), all with favorable clinical outcome. Risk factors have low to moderate predictive value to identify complicated SAB and their use may lead to unnecessary prolonged antibiotic use.

The Changing Epidemiology and Antimicrobial Susceptibility of Staphylococcus aureus Isolated from Blood Cultures in a University Hospital from Argentina.

Staphylococcus aureus bacteremia (SAB) is one of the most common serious bacterial infections worldwide. In this study, we demonstrated changes in SAB epidemiology in an Argentinean University Hospital during an 8-year period (2009-2016). A total of 326 S. aureus clinical isolates were recovered in three periods: P1: 2009-2010, P2: 2012-2014, and P3: 2015-2016. Among these, 127 were methicillin-resistant S. aureus (MRSA) and were characterized by phenotypic and molecular methods. We hereby report a significant decline in multiple drug resistance among MRSA isolates associated with an increase in SCCmec IV between the three periods. A diversity of MRSA-IV clones (mainly ST30-MRSA-IV, ST5-MRSA-IV, and ST8-MRSA-IV) replaced between 2009 and 2016 the previous prevalent MRSA clone causing bloodstream infections at this hospital (ST5-MRSA-I). MRSA population structure continued to diversify between P2 and P3. Notably, ST8-MRSA-IV-t008 related to USA300 was first detected during P2, and ST8-MRSA-IV together with ST30-MRSA-IV related to the Southwest Pacific clone were the more prevalent MRSA genotypes circulating during P3.

209. Validation of a New Risk Stratification System-Based Management for Methicillin-Resistant Staphylococcus aureus Bacteremia: Analysis of a Multicenter Prospective Study

Abstract Background Distinguishing between complicated and uncomplicated Staphylococcus aureus bacteremia (SAB) is therapeutically essential. However, this distinction has limitations in reflecting the various manifestation of SAB. In the light of this, Koujizer et al. proposed a new risk stratification system for metastatic infection in SAB, which involves a stepwise approach to diagnosis and treatment. We tested this risk stratification system in methicillin-resistant SAB (MRSAB) patients. Methods We retrospectively analyzed data of a 3-year multicenter, prospective cohort of hospitalized patients with MRSAB. We classified the patients into three risk groups: low, indeterminate, and high, based on the new system and compared between-group management and outcomes, as well as microbiologic features. Results The demographic and baseline characteristics of patients are shown in Table 1. The most frequent source of MRSAB was central venous catheter-related infection (25.5%), followed by unknown origin (15.3%) and pneumonia (11.1%). Echocardiography was performed in 248 cases (65.3%). Of 380 patients with MRSAB, 6.3% were classified as low-, 7.6% as indeterminate-, and 86.1% as high-risk for metastatic infection (Figure 1). No metastatic infection occurred in the low-, 6.9% in the indeterminate-, and 17.7% in the high-risk groups (P=0.03) (Figure 2A). After an in-depth diagnostic work-up, patients were finally diagnosed as ‘without metastatic infection (6.3%)’, ‘with metastatic infection (15.8%)’, and ‘uncertain metastatic infection (77.9%)’. 30-day mortality increased markedly as the severity of diagnosis shifted from ‘without metastatic infection’ to ‘uncertain’ and ‘with metastatic infection’ (P=0.07) (Figure 2B). In multivariable analysis, independent factors associated with metastatic complications were suspicion of endocarditis in transthoracic echocardiography, clinical signs of metastatic infection, Pitt bacteremia score ≥4, and persistent bacteremia. Figure 1. Flowchart of risk stratification and final diagnosis Figure 2. Outcomes of metastatic infection and 30-day mortality. A, metastatic infection according to the risk stratification, B, 30-day mortality according to the final diagnosis Conclusion The new risk stratification system provides good discrimination in predicting metastatic complications, making it a reliable tool for guiding work-up and management of MRSAB. However, minimizing the number of ‘uncertain metastatic infection’ cases remains an area for improvement. Disclosures All Authors: No reported disclosures

Australian Group on Antimicrobial Resistance (AGAR) Australian Staphylococcus aureus Surveillance Outcome Program (ASSOP) Bloodstream Infection Annual Report 2022.

From 1 January to 31 December 2022, fifty-five institutions across Australia participated in the Australian Staphylococcus aureus Surveillance Outcome Program (ASSOP). The aim of ASSOP 2022 was to determine the proportion of Staphylococcus aureus bacteraemia (SAB) isolates in Australia that were antimicrobial resistant, with particular emphasis on susceptibility to methicillin and on characterisation of the molecular epidemiology of the methicillin-resistant isolates. A total of 3,214 SAB episodes were reported, of which 77.5% were community-onset. Overall, 15.0% of S. aureus were methicillin resistant. The 30-day all-cause mortality associated with methicillin-resistant SAB was 21.4%, which was significantly different to the 16.8% all-cause mortality associated with methicillin-susceptible SAB (p = 0.02). With the exception of the β-lactams and erythromycin, antimicrobial resistance in methicillin-susceptible S. aureus was rare. However, in addition to the β-lactams, approximately 31% of methicillin-resistant S. aureus (MRSA) were resistant to ciprofloxacin; 30% to erythromycin; 13% to tetracycline; 11% to gentamicin; and 2% to co-trimoxazole. One MRSA isolate, with a daptomycin MIC of 1.5 mg/L, harboured the A302V mprF and A23V cls2 mutations. When applying the European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints, teicoplanin resistance was detected in one MRSA isolate. Resistance to vancomycin or linezolid was not detected. Resistance to non-β-lactam antimicrobials was largely attributable to the healthcare-associated MRSA (HA-MRSA) clone ST22-IV [2B] (EMRSA-15), and to the community-associated MRSA (CA-MRSA) clone ST45-V [5C2&5] which has acquired resistance to multiple antimicrobials including ciprofloxacin, clindamycin, erythromycin, gentamicin, and tetracycline. The ST22-IV [2B] (EMRSA-15) clone is the predominant HA-MRSA clone in Australia. Nonetheless, 86% of methicillin-resistant SAB episodes were due to CA-MRSA clones. Although polyclonal, approximately 72% of CA-MRSA clones were characterised as ST93-IV [2B] (Queensland clone); ST5-IV [2B]; ST45-V [5C2&5]; ST1-IV [2B]; ST30-IV [2B]; ST97-IV [2B]; ST953-IV [2B]; and ST8-IV [2B]. As CA-MRSA is well established in the Australian community, it is important to monitor antimicrobial resistance patterns in community- and healthcare-associated SAB as this information will guide therapeutic practices in treating S. aureus bacteraemia.

Factors for mortality in patients with persistent Staphylococcus aureus bacteremia: The importance of treatment response rather than bacteremia duration.

The criteria for antibiotic failure in persistent Staphylococcus aureus bacteremia (SAB) are unclear, but treatment response and bacteremia duration are commonly used indicators of antibiotic failure. We evaluated the effects of treatment response and bacteremia duration on mortality in persistent SAB. We retrospectively identified patients with persistent SAB in four university-affiliated hospitals between 2017 and 2021. Bacteremia duration was calculated from the first day of active antibiotic therapy, and persistent SAB was defined as bacteremia lasting for 2 or more days. Defervescence and Pitt bacteremia score (PBS) were used to evaluate treatment response at treatment day 4. The primary outcome was 30-day in-hospital mortality. Time-dependent multivariable Cox regression analysis and subgroup analysis according to methicillin resistance were performed. A total of 221 patients was included in the study, and the 30-day in-hospital mortality was 28.5%. There was no significant difference in bacteremia duration between survived and deceased patients. Independent factors for mortality included age, Charlson comorbidity index, initial PBS, pneumonia, and removal of the eradicable focus. PBS at treatment day 4≥3 was the strongest risk factor (adjusted hazard ratio [HR]=4.260), but defervescence was not. Bacteremia duration was not an independent factor except for 13 days or more of methicillin-resistant SAB (adjusted HR=1.064). In patients with persistent SAB, PBS at treatment day 4 was associated with 30-day in-hospital mortality rather than defervescence and bacteremia duration. The results of this study could help determine early intensified treatment strategies in persistent SAB patients.

Risk Factors and Outcomes of Hematogenous Vertebral Osteomyelitis in Patients With Staphylococcus aureus Bacteremia.

Hematogenous vertebral osteomyelitis (HVOM) is an incompletely understood complication of Staphylococcus aureus bacteremia (SAB). Eligible SAB patients with and without HVOM were prospectively enrolled from 1995 through 2019 at Duke University Health System. HVOM was diagnosed either radiographically or microbiologically. Multivariable logistic regression analysis was performed to identify clinical and microbial factors associated with HVOM risk. All bloodstream S. aureus isolates were genotyped using spa typing. Of 3165 cases of SAB, 127 (4.0%) developed HVOM. Patients who experienced HVOM were more likely to have community-acquired SAB (30.7% vs 16.7%, P < .001), have a longer time to diagnosis of SAB (median, 5 days; interquartile range [IQR], 2-10.5 vs median, 2 days; IQR, 0-4; P < .001), and to exhibit persistent bacteremia (48.8% vs 20.6%, P < .001). A significant number of HVOM patients developed infective endocarditis (26% vs 15.2%, P = .002). Overall, 26.2% (n = 33) of SAB patients with HVOM underwent surgical intervention. Methicillin resistance (46.6% vs 41.7%, P = .318) and bacterial genotype were not associated with the development of HVOM. At the 12-month follow-up, 22% of patients with HVOM had died. Of the surviving patients, 20.4% remained on antibiotic therapy, and 29.6% had recurrence of either HVOM or SAB. Among patients with SAB, HVOM risk was associated with clinical factors and not bacterial genotype. Despite being a rare complication of SAB, patients with HVOM had high all-cause mortality rates and healthcare resource requirements up to 1 year after their HVOM diagnosis. Close clinical monitoring is indicated in this vulnerable population.

Impact of Early Chemotherapy Resumption on the Outcome after Staphylococcus aureus Bacteremia in Patients with Solid Tumors: A Retrospective Study in a Single Tertiary Cancer Center in Japan

Objective. Staphylococcus aureus bacteremia (SAB) in patients with solid tumors poses a dilemma between infection control and cancer treatment. We aimed to explore whether early resumption of chemotherapy yielded unfavorable outcomes in oncologic patients with SAB. Methods. We retrospectively reviewed patients who received chemotherapy within 90 days of SAB onset from 2011 to 2020. We divided patients who resumed chemotherapy into two groups by the median time from the negative blood culture to the chemotherapy resumption. We investigated the association with treatment failure, which included recurrence after completion of SAB treatment, relapse during antibiotics therapy, 90-day all-cause mortality after initiation of antibiotics, and 30-day all-cause mortality after the resumption of chemotherapy. Results. Among the 78 eligible patients, 36 patients resumed chemotherapy. The median interval to the chemotherapy resumption was 17.5 days. Two patients in the early resumption group and one in the late resumption group died within 90 days after initiating antibiotics. One patient in the early resumption group experienced SAB recurrence. None of the patients experienced SAB relapse or died within 30 days of resuming chemotherapy. Conclusion. Early resumption of chemotherapy may not be directly associated with unfavorable outcomes in oncological patients with SAB under appropriate infection management.

Predictors of infectious foci on FDG PET/CT in Staphylococcus aureus bacteremia

We looked for predicting factors for the detection of infectious foci on 18F-fluorodeoxyglucose-positron emission tomography in combination with computed tomography (FDG PET/CT) among patients with Staphylococcus aureus bacteremia (SAB) who participated in an interventional study that was conducted at Rambam Health Care Campus, between July 1, 2015 and February 1, 2019. The primary outcome was an infectious focus detected by FDG PET/CT. Independent predictors for detection of focal infection were identified using univariate followed by a logistic regression multivariate analysis. We included 149 patients with 151 separate episodes of SAB who underwent FDG-PET/CT. Focal infections were detected in 107 patients (70.8%). Independent predictors for focal infection detection were community acquisition of bacteremia with odds ratio (OR) 3.03 [95% confidence interval (CI) 1.04–8.77], p-0.042 and C reactive protein (CRP) with OR 1.09 [95% CI 1.04–1.14], p < 0.001. Primary bacteremia was inversely associated with focal infection detection with OR 0.27 [0.10–0.69], p = 0.007, as were the pre-scan blood glucose levels OR 0.9 [0.98–0.99], p-0.004. The latter stayed significant in the subgroup of patients with diabetes mellitus. To conclude, patients with community-acquired bacteremia or high CRP levels should be carefully investigated for focal infection. Patients who present with primary bacteremia seem to be at low risk for focal infection.

Effectiveness of adjunctive rifampicin for treatment of Staphylococcus aureus bacteraemia: a systematic review and meta-analysis of randomized controlled trials.

To assess whether the addition of rifampicin to conventional treatment of Staphylococcus aureus bacteraemia (SAB) reduces bacteriological or clinical failure or death. PubMed, Embase and Cochrane CENTRAL databases were searched from inception to 31 December 2022. Reference lists and PubMed citations of eligible studies were checked. Two study authors independently identified randomized controlled trials (RCTs) involving adult participants with SAB, in which an intervention group received adjunctive rifampicin and the control group received usual care with or without a placebo. Dichotomous data (bacteriological and clinical failure and deaths) were analysed and pooled across studies using risk ratio (RR) with 95% confidence intervals (CI) using a Mantel-Haenszel random-effect model. The key variable of interest being whether rifampicin was used. Six RCTs including 894 participants-of which 758 (85%) were from one trial-met the inclusion criteria. The addition of rifampicin to conventional treatment of SAB significantly reduced bacteriological failure by 59% (RR 0.41, 95% CI 0.21-0.81, I2 = 0%, number need to treat 27). However, it did not reduce clinical failure (RR 0.70, 95% CI 0.47-1.03, I2 = 0%) or deaths (RR 0.96, 95% CI 0.70-1.32, I2 = 0%). Further, it did not reduce the duration of bacteraemia, or the length of hospital stay. Adjunctive rifampicin reduced SAB recurrences (1% versus 4%, P = 0.01). Emergence of rifampicin resistance during treatment was uncommon (<1%). Although adjunctive rifampicin reduced the risk of bacteriological failure and recurrences, we found no mortality benefit to support its use in SAB.

A 78-year-old Man Presented with Knee Pain and Recurrent Fever

&lt;p&gt;發燒為常見臨床症狀，本案例是一位78歲末期腎臟疾病接受長期血液透析治療男性，近一個月曾發生永久性透析導管感染合併金黃色葡萄球菌菌血症，此次因左膝關節疼痛就醫，理學檢查發現關節發熱腫脹，診斷感染性關節炎入院治療， 關節液及血液培養顯示金黃色葡萄球菌，在抗生素治療及行左膝切除關節成形術後仍反覆發燒， 經由專科護理師完整病史收集、全身理學檢查、實驗室檢驗結果，排除導管感染及心內膜炎等相關鑑別診斷，電腦斷層血管攝影顯示囊狀主動脈合併周圍積液確診為感染性動脈瘤。因年紀大合併多種慢性共病（塵肺症、慢性阻塞性肺病及末期腎臟疾病等），在家屬考量動脈瘤切除、結紮及血管重建手術利弊後決定採保守治療（6週Piperacillin-Tazobactam和Vancomycin抗生素靜脈注射療程），發燒及低血壓狀況改善，且血液培養亦未發現新的感染。臨床上，當病人主訴反覆發燒合併金黃色葡萄球菌菌血症時，根據我們的案例及文獻回顧，應強調以焦點式理學檢查積極探查可能的轉移性感染（包括：導管感染、軟組織感染、感染性關節炎、心內膜炎及感染性動脈瘤等），輔以影像學檢查。以此案例提升專科護理師於類似複雜案例時的照顧能力，利於醫療團隊即早確定診斷及介入治療，以降低延遲治療對於脆弱老年病人帶來負面影響。&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;&lt;p&gt;Fever is a common symptom in clinical practice. A 78-year-old male with end-stage kidney disease (ESKD) who underwent hemodialysis was admitted due to left knee pain. Upon physical examination, there were signs of joint heat, swelling, and tenderness in addition to febrile state, suggesting a diag&amp;shy;nosis of septic arthritis. Staphylococcus aureus (SA) was later identified in both the synovial fluid and blood culture. However, the patient experienced recurrent fever despite receiving appropriate antimi&amp;shy;crobial treatment and undergoing left knee resectional arthroplasty. To rule out other potential diagno&amp;shy;ses related to SA bacteremia, a thorough evaluation involving medical history, physical examination, and laboratory tests was conducted. The computed tomography angiography revealed the presence of a saccular aortic aneurysm with perianeurysmal fluid collection, confirming a diagnosis of mycotic an&amp;shy;eurysm. The patient and his family carefully considered the advantages and disadvantages of surgical options, such as aneurysm excision, ligation, or vessel reconstruction. Under the considerations of the age and underlying comorbidities such as pneumoconiosis, chronic obstructive pulmonary disease, and ESKD, conservative treatment was performed (a 6-week course of intravenous piperacillin-tazobactam and vancomycin). The fever and hypotension gradually subsided, and there was no evidence of blood&amp;shy;stream infection. Based on our case and extensive literature reviews, it is crucial to actively evaluate metastatic complications, including infective endocarditis, catheter infection, septic arthritis, and my&amp;shy;cotic aneurysm, among patients who present with persistent fever and concurrent SA bacteremia. This case aims to enhance the abilities of nurse practitioners in conducting comprehensive assessments, providing vital information to the medical team, facilitating accurate diagnoses, timely interventions, and ultimately reducing the adverse impact of delayed treatment in vulnerable older adults.&lt;/p&gt; &lt;p&gt;&amp;nbsp;&lt;/p&gt;