Risk factors for hematogenous complications of intravascular catheter-associated Staphylococcus aureus bacteremia

Risk Factors for Persistent Staphylococcus aureus Bacteremia in Children

BACKGROUND

Staphylococcus aureus is a leading cause of pediatric bacteremia. Persistent S. aureus bacteremia (SAB) is associated with increased morbidity and mortality in adults and children. Risk factors for S. aureus bacteremia have been well established, but there is a limited understanding of the factors that contribute to the development of persistent SAB in children.

METHODS

This is a single-center retrospective secondary analysis of a prospective observational study of pediatric patients hospitalized with S. aureus infection over a 3.5-year period at a large, quaternary, children's hospital.

RESULTS

Two hundred fifty-nine children with confirmed S. aureus infection were enrolled in the study. Sixty-five of these were found to have bacteremia, with 28 (43%) developing persistent bacteremia. Patients with persistent SAB were culture-positive for a median of 3.5 days compared with 1 day for those without (P ≤ 0.001). Children with persistent SAB were more likely to have an identified osteoarticular source of infection (93%, n = 26 vs. 62%, n = 23; P = 0.008) and had a shorter median duration to culture positivity than those without persistent SAB (16 hours vs. 20 hours; P ≤ 0.001). In addition, children with persistent SAB had higher median values of presenting erythrocyte sedimentation rate, peak erythrocyte sedimentation rate, presenting C-reactive protein and peak C-reactive protein. Not surprisingly, hospital length of stay was longer in children with persistent SAB compared with those without.

CONCLUSIONS

These findings suggest that a shorter time to culture positivity, osteoarticular infection, and higher presenting and peak values for select inflammatory markers are potential risk factors for persistent SAB in children.

Salvage strategy for long-term central venous catheter-associated Staphylococcus aureus infections in children: a multicenter retrospective study in France

OBJECTIVES

Catheter removal is recommended in adults with S. aureus central line-associated bloodstream infection (CLABSI) but is controversial in children with long-term central venous catheters (LTCVC). We evaluated the occurrence of catheter salvage strategy (CSS) in children with S. aureus LTCVC-associated CLABSI and assessed determinants of CSS failure.

METHODS

We retrospectively included children (<18 years) with an LTCVC and hospitalized with S. aureus CLABSI in 8 French tertiary care hospitals (2010-2018). CSS was defined as an LTCVC left in place ≥ 72 hours after initiating empiric antibiotic treatment for suspected bacteremia. Characteristics of patients were reviewed, and multivariable logistic regression was performed to identify factors associated with CSS failure (i.e., persistence, recurrence, or complications of bacteremia).

RESULTS

We included 273 episodes of S. aureus LTCVC-associated CLABSI. CSS was chosen in 194 out of 273 (71%) cases and failed in 74 of them (38%). The main type of CSS failure was the persistence of bacteremia (39 out of 74 cases, 53%). Factors independently associated with CSS failure were: history of catheter infection (adjusted odds ratio [aOR] 3.18, 95% confidence interval [95%CI] 1.38-7.36), CLABSI occurring on an implantable venous access device (aOR 7.61, 95%CI 1.98-29.20) when compared with tunneled-cuffed CVC, polymicrobial CLABSI (aOR 3.45, 95%CI 1.25-9.50), and severe sepsis at the initial stage of infection (aOR 4.46, 95%CI 1.18-16.82).

CONCLUSIONS

CSS was frequently chosen in children with S. aureus LTCVC-associated CLABSI, and failure occurred in one-third of cases. The identified risk factors may help clinicians identify children at risk for CSS failure.

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

INTRODUCTION

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.

METHODS

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.

RESULTS

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.

CONCLUSIONS

Risk factors have low to moderate predictive value to identify complicated SAB and their use may lead to unnecessary prolonged antibiotic use.

Central venous catheter-related bloodstream infections: Epidemiology and risk factors for hematogenous complications

BACKGROUND

Central catheter-related bloodstream infections (CRBIs) can lead to severe complications, including suppurative thrombophlebitis, endocarditis, and metastatic infections. While complications due to CRBIs caused by Staphylococcus aureus (SA) are well-known, there are limited data regarding CRBIs caused by other bacteria.

METHODS

This 2-year retrospective single-center study of patients with CRBIs from a tertiary care hospital examined the hematogenous complications associated with CRBIs according to patient characteristics, central venous catheter (CVC) types, and causative bacteria.

RESULTS

All in all, 254 patients with confirmed CRBIs were included; 285 bacteria types were isolated, mainly Enterobacteriaceae (n = 94), coagulase-negative Staphylococci (CNS, n = 82), SA (n = 45), and non-fermenting Gram-negative bacteria (NGB, n = 45). Among the patients, 35 developed at least one hematogenous complication (14 %), including suppurative thrombophlebitis (n = 15), endocarditis (n = 7) and metastatic infections (n = 16). In multivariate analysis, hemodialysis, persistent bacteremia for at least 3 days, and CRBIs caused by SA were associated with increased risk for hematogenous complications, while previous curative anticoagulant treatment was associated with reduced risk. Diabetes, CVC maintenance, and hematogenous complications were associated with increased 3-month mortality.

CONCLUSION

A thorough investigation of hematogenous complications should be envisioned in patients with persistent bacteremia, particularly those with SA infections and those on hemodialysis.

Metastatic spondylodiscitis in central venous catheter related bloodstream infections in hemodialysis patients: Risk factors and prognosis

BACKGROUND

Infection is one of the most common causes of death in hemodialysis patients. Catheter infections are among the most common infections in this patient group. Spondylodiscitis which has a high incidence in ESRD is more commonly encountered in patients with CVCs compared to AVF. In this study, we aimed to evaluate the frequency and risk factors of spondylodiscitis in catheter-related bloodstream infections in hemodialysis patients.

METHODS

In total, 1620 patients were screened and 42 male and 35 female patients with central catheter infection with a mean age of 65.8 ± 14.9 years were included in this study. Patients with metastatic infections secondary to CVC related bloodstream infections were determined. The diagnosis of spondylodiscitis was based on clinical information, computed tomography (CT) and magnetic resonance imaging (MRI), and vertebral cultures.

RESULTS

Metastatic infection due to catheter infection was observed in 15 patients (19.5%). In the regression analysis, CRP level and RRT time were found to be significantly correlated with the development of metastatic infection. Spondylodiscitis was the most common subtype of metastatic infections (8/15). The presence of lumbar hernia was associated with increased risk of metastatic spondylodiscitis in case of catheter infection in hemodialysis patients. The only factor associated with resistance to medical treatment was the time from admission to diagnosis.

CONCLUSION

Patients with long RRT time and high blood CRP levels on admission should be closely monitored for metastatic infection in patients with CVC related bloodstream infections. Screening for spondylodiscitis with CT or MRI should be performed in patients with symptoms, since early diagnosis may prevent the development of possible neurological deficits and treatment resistance.

Central venous catheter (CVC) salvage in case of central line-associated bloodstream infection (CLABSI): A monocentric prospective study in patients on long-term home parenteral nutrition (HPN)

BACKGROUND & AIMS

CLABSI is a major complication in HPN and frequently leads to central venous catheter (CVC) removal. We developed a salvaging attitude in long term HPN patients due to the necessity of venous preservation. The main objective of this study is to determine the prognosis of CLABSI.

METHODS

We followed-up for three months, in an approved HPN centre, a cohort of 250 adult patients receiving HPN with CLABSI from 2018 to 2020. CLABSI was defined by a blood culture growth differential [peripheral blood] - [CVC blood] ≥ 2h. A therapeutic approach to conserve CVC was established according to the department's protocol. The primary endpoint was conservation of CVC with negative CVC and peripheral blood cultures at 3 months without complications.

RESULTS

Data from 30 CLABSIs were collected for 22 HPN patients. The incidence rate of CLABSIs was 0.28 infections/1000 catheter days. Sixteen CVCs were removed immediately, with causes due to the type of germ (staphylococcus aureus: n = 6, candida parapsilosis: n = 4, klebsiella: n = 2), chronic colonization (n = 4) or initial complications (n = 4). Among the 14 non-removed CVC, 11 were maintained at 3 months with blood cultures on CVC and peripheral negative for 9 (80%) of them. 3 CVC were removed during the 3 months follow-up (non-CVC-related sepsis n = 2, and resistant pseudomonas aeruginosa n = 1).

CONCLUSION

The incidence rate of CLABSIs in an expert HPN centre remains low. In case of CLABSIs, according to specific protocol, approximately 50% of CVC were removed immediately (essentially due to bacteriological characteristics). In case of CLABSIs and without initial complication, 80% of CVCs can be maintained at 3 months. These results justify a conservative attitude according to standardized protocol.

Contemporary Management of Staphylococcus aureus Bacteremia-Controversies in Clinical Practice

Staphylococcus aureus bacteremia (SAB) carries a high risk for excess morbidity and mortality. Despite its prevalence, significant practice variation continues to permeate clinical management of this syndrome. Since the publication of the 2011 Infectious Diseases Society of America (IDSA) guidelines on management of methicillin-resistant Staphylococcus aureus infections, the field of SAB has evolved with the emergence of newer diagnostic strategies and therapeutic options. In this review, we seek to provide a comprehensive overview of the evaluation and management of SAB, with special focus on areas where the highest level of evidence is lacking to inform best practices.

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

BACKGROUND

Hematogenous vertebral osteomyelitis (HVOM) is an incompletely understood complication of Staphylococcus aureus bacteremia (SAB).

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.

Predictive models for sepsis in children with Staphylococcus aureus bloodstream infections: a retrospective cohort study

BACKGROUND

The presence of Staphylococcus aureus in the bloodstream can lead to the development of sepsis; however, the severity and risk factors of the systemic inflammatory response to Staphylococcus aureus bloodstream infections were unclear. This study is aimed to build a model to predict the risk of sepsis in children with Staphylococcus aureus bloodstream infections.

METHODS

A retrospective analysis of hospitalized pediatric patients diagnosed with Staphylococcus aureus bloodstream infections was performed between January 2013 and December 2019. Each patient was assessed using the pediatric version of the Sequential Organ Failure Assessment score (pSOFA) within 24 h of blood culture collection. A nomogram based on logistic regression models was constructed to predict the risk factors for sepsis in children with Staphylococcus aureus bloodstream infections. It was validated using the area under the receiver-operating characteristic curve (AUC).

RESULTS

Of the 94 patients included in the study, 35 cases (37.2%) developed sepsis. The pSOFA scores ranged from 0 to 8, with 35 patients having a pSOFA score of ≥ 2. Six children (6.4%) died within 30 days, who were all from the sepsis group and had different pSOFA scores. The most common organs involved in sepsis in children with staphylococcal bloodstream infections were the neurologic system (68.6%), respiratory system (48.6%), and coagulation system (45.7%). Hospital-acquired infections (adjusted odds ratio [aOR], 3.0; 95% confidence interval [CI], 1.3-7.2), implanted catheters (aOR, 10.4; 95% CI, 3.8-28.4), procalcitonin level ≥ 1.7 ng/mL (aOR, 15.4; 95% CI, 2.7-87.1), and underlying diseases, especially gastrointestinal malformations (aOR, 14.0; 95% CI, 2.9-66.7) were associated with Staphylococcus aureus sepsis. However, methicillin-resistant Staphylococcus aureus infection was not a risk factor for sepsis. The nomogram had high predictive accuracy for the estimation of sepsis risk, with an AUC of 0.85.

CONCLUSIONS

We developed a predictive model for sepsis in children with Staphylococcus aureus infection.

Clinical and microbiological characteristics of rifampicin-resistant MRSA bacteraemia

OBJECTIVES

The clinical significance of rifampicin resistance in Staphylococcus aureus infections has not been demonstrated. Here, we evaluated the clinical characteristics of rifampicin-resistant S. aureus infection.

METHODS

Data were collected from adult patients who were hospitalized with MRSA bacteraemia between March 2007 and May 2020 at a tertiary hospital in South Korea. The clinical characteristics and treatment outcomes of patients infected with rifampicin-resistant MRSA were compared with those of rifampicin-susceptible isolates. All-cause death and recurrence of MRSA infection were assessed for 90 days.

RESULTS

Of the 961 patients with MRSA bacteraemia, 61 (6.3%) were infected by rifampicin-resistant isolates. The type of infection focus and duration of bacteraemia did not significantly differ between the two groups. Rifampicin-resistant MRSA isolates were more likely to have multidrug resistance and a higher vancomycin MIC relative to the rifampicin-susceptible isolates. The 90-day recurrence rate was higher in the patients infected with rifampicin-resistant MRSA compared with those with rifampicin-susceptible MRSA (18.0% versus 6.2%, P < 0.001), whereas the 90-day mortality was comparable between the two groups (27.9% versus 29.2%, P = 0.94). After adjusting for potential confounding factors, rifampicin resistance was significantly associated with 90-day recurrence (subdistributional HR: 2.31; 95% CI: 1.05-5.10; P = 0.04).

CONCLUSIONS

Rifampicin-resistant MRSA isolates showed distinct microbiological features in terms of multidrug resistance and a high vancomycin MIC. Although the management of MRSA bacteraemia was not significantly different between the two groups, recurrence was significantly more common in the rifampicin-resistant group. Rifampicin resistance may play a significant role in infection recurrence.

Follow-up blood cultures in Staphylococcus aureus bacteremia: a probability-based optimization

Staphylococcus aureus bacteremia (SAB) is a relevant finding which prompts a thorough diagnostic work-up. Follow-up blood cultures (BC) are essential in this work-up. We investigate the probability of detecting an ongoing bacteremia after initiation of active therapy according to the number of BC taken at key time points. A retrospective analysis of all patients with SAB in a 6-year period was performed. Total number of BCs taken and the positivity was registered for each day after start of therapy. A positivity-rate was corrected using a logistic mixed effects model. Observed detection frequencies were applied to calculate detection probabilities using binomial distributions. Three hundred and seventeen cases were withheld for analysis. A BC bottle positivity rate of 66.7% was found 1 day after initiation of active therapy, which decreased to 48.5% on day 4. When using 1 set of FU-BC, 73.4% of persisting SABs are detected. To maintain a probability of detection of ≥ 90%, 2 BC sets should be taken on day 2 and day 4 after start of therapy. In 10 of 109 patients with positive FU-BC, skip phenomena were registered, with a significant higher proportion in patients with < 4 BC bottles taken (14%) than when ≥ 4 BC bottles were taken (4.1%). We recommend taking 2 BC sets on days 2 and 4 after start of therapy in order to detect ≥ 90% of persisting SABs, limiting skip phenomena and blood volume required. We strongly advice against taking a single BC set as follow-up for SAB.

In vitro Activities of N-Acetyl Cysteine and Levofloxacin as a Catheter Lock Therapy against Catheter-Associated Infections

AIMS

Since management of catheter-associated infections, which are generally biofilm-based, is attempted in certain patients such as older and frail patients by using a catheter lock solution (CLS), we examined the combination of N-acetyl cysteine (NAC), an antibiofilm agent, and levofloxacin, a broad-spectrum antimicrobial agent, for this purpose.

METHODS AND RESULTS

Intravascular catheters were colonized with methicillin-resistant Staphylococcus epidermidis, levofloxacin-sensitive/methicillin-resistant S. aureus, levofloxacin-resistant/methicillin-resistant S. aureus, vancomycin-resistant Enterococcus, Escherichia coli, Klebsiella pneumoniae, or Pseudomonas aeruginosa and treated with a CLS containing normal saline, NAC, levofloxacin, or NAC plus levofloxacin (NACLEV) and then cultured to assess their antimicrobial activities. We also examined antibiofilm and antimicrobial activities of each CLS by scanning electron microscopy (SEM) and the mechanical integrity of catheters exposed to CLS. Treatment of colonized catheters with NACLEV-CLS significantly reduced colonization (P < 0.005) against all pathogens. SEM images also indicate reduction in colonization with NACLEV-CLS with considerable reduction in both visible bacteria and the associated biofilm. Mean tensile strength of catheters exposed to CLS was not significantly different compared to controls (P>0.05).

CONCLUSIONS

These in-vitro results suggest that NACLEV-CLS can significantly reduce all bacterial colonization and potentially help salvage infected catheters without affecting the catheter's mechanical integrity.

SIGNIFICANCE AND IMPACT OF STUDY

This study presents a novel CLS with a broad spectrum of antimicrobial activity against catheter-associated infections, particularly in long-term catheters.

The Hamburg Spondylodiscitis Assessment Score (HSAS) for Immediate Evaluation of Mortality Risk on Hospital Admission

(1) Background: Patients with spondylodiscitis often present with unspecific and heterogeneous symptoms that delay diagnosis and inevitable therapeutic steps leading to increased mortality rates of up to 27%. A rapid initial triage is essential to identify patients at risk for a complicative disease course. We therefore aimed to develop a risk assessment score using fast available parameters to predict in-hospital mortality of patients admitted with spondylodiscitis. (2) Methods: A retrospective data analysis of 307 patients with spondylodiscitis recruited from 2013 to 2020 was carried out. Patients were grouped according to all-cause mortality. Via logistic regression, individual patient and clinical characteristics predictive of mortality were identified. A weighted sum score to estimate a patient's risk of mortality was developed and validated in a randomly selected subgroup of spondylodiscitis patients. (3) Results: 14% of patients with spondylodiscitis died during their in-hospital stay at a tertiary center for spinal surgery. Univariate and logistic regression analyses of parameters recorded at hospital admission showed that age older than 72.5 years, rheumatoid arthritis, creatinine > 1.29 mg/dL and CRP > 140.5 mg/L increased the risk of mortality 3.9-fold, 9.4-fold, 4.3-fold and 4.1-fold, respectively. S. aureus detection increased the risk of mortality by 2.3-fold. (4) Conclusions: The novel Hamburg Spondylodiscitis Assessment Score (HSAS) shows a good fit identifying patients at low-, moderate-, high- and very high risk for in hospital mortality on admission (AUC: 0.795; p < 0.001). The implementation of the HSAS into clinical practice could ease identification of high-risk patients using readily available parameters alone, improving the patient's safety and outcome.

Comparing success rates in central venous catheter salvage for catheter-related bloodstream infections in adult patients on home parenteral nutrition: a systematic review and meta-analysis

BACKGROUND

Catheter-related bloodstream infection (CRBSI) is a life-threatening complication of parenteral nutrition. Therefore, optimal management, ideally with catheter salvage, is required to maintain long-term venous access.

OBJECTIVES

We aimed to evaluate successful catheter salvage rates in patients on home parenteral nutrition (HPN).

METHODS

Studies were retrieved from medical databases, conference proceedings, and article reference lists. Data were collected relating to clinical outcomes of 3 treatments: systemic antibiotics, antimicrobial lock therapy (ALT), and catheter exchange. ORs and 95% CIs were calculated from a mixed logistic effects model.

RESULTS

From 10,036 identified publications, 28 met the inclusion criteria (22 cohort studies, 5 case-control studies, and 1 randomized clinical trial), resulting in a total of 4911 CRBSIs. To achieve successful catheter salvage, the addition of an antimicrobial lock solution was superior to systemic antibiotics alone (OR: 1.75; 95% CI: 1.21, 2.53; P = 0.003). Recurrence of infection was less common in studies that used ALT than in those that used systemic antibiotics alone (OR: 0.26; 95% CI: 0.11, 0.61; P = 0.002). The catheter exchange group was excluded from multilevel regression analysis because only 1 included study applied this treatment. Successful salvage rates were highest for coagulase-negative staphylococci, followed by Gram-negative rods and Staphylococcus aureus .

CONCLUSIONS

The addition of an antimicrobial lock solution seems beneficial for successful catheter salvage in HPN-dependent patients with a CRBSI. Future prospective randomized studies should identify the most effective and pathogen-specific strategy.This review was registered at www.crd.york.ac.uk/PROSPERO as CRD42018102959.

Infección metastásica por Staphylococcus aureus en neonatos: a propósito de un caso

Metastatic infection as an infrequent complication of Staphylococcus aureus bacteremia in neonates is challenging due to the limited literature. To report the clinical case of a premature neonate who developed a metastatic infection as a complication of S. aureus bacteremia. We present the case of a premature neonate admitted to the Neonatal Intensive Care Unit, diagnosed with bacterial sepsis, neonatal respiratory distress syndrome, and involvement by premature rupture of the membrane. A patch catheter was inserted, and he was successfully treated for E. coli bacteremia. He was re-admitted for late sepsis due to infection with multi-sensitive S. aureus in a patch catheter. An abscess appears on the front of the chest due to S. aureus, confirming metastatic infection. The abscess was drained with a favorable resolution of the clinical picture. In neonates submitted to invasive procedures, it is essential to monitor the clinical evolution and early identification of metastatic infection after Staphylococcus aureus bacteremia and provide early treatment to avoid sequelae.

Multicentre, randomised, open-label, phase IV-III study to evaluate the efficacy of cloxacillin plus fosfomycin versus cloxacillin alone in adult patients with methicillin-susceptible Staphylococcus aureus bacteraemia: study protocol for the SAFO trial

INTRODUCTION

Methicillin-susceptible Staphylococcus aureus (MSSA) bacteraemia is a frequent condition, with high mortality rates. There is a growing interest in identifying new therapeutic regimens able to reduce therapeutic failure and mortality observed with the standard of care of beta-lactam monotherapy. In vitro and small-scale studies have found synergy between cloxacillin and fosfomycin against S. aureus. Our aim is to test the hypothesis that cloxacillin plus fosfomycin achieves higher treatment success than cloxacillin alone in patients with MSSA bacteraemia.

METHODS

We will perform a superiority, randomised, open-label, phase IV-III, two-armed parallel group (1:1) clinical trial at 20 Spanish tertiary hospitals. Adults (≥18 years) with isolation of MSSA from at least one blood culture ≤72 hours before inclusion with evidence of infection, will be randomly allocated to receive either cloxacillin 2 g/4-hour intravenous plus fosfomycin 3 g/6-hour intravenous or cloxacillin 2 g/4-hour intravenous alone for 7 days. After the first week, sequential treatment and total duration of antibiotic therapy will be determined according to clinical criteria by the attending physician.Primary endpoints: (1) Treatment success at day 7, a composite endpoint comprising all the following criteria: patient alive, stable or with improved quick-Sequential Organ Failure Assessment score, afebrile and with negative blood cultures for MSSA at day 7. (2) Treatment success at test of cure (TOC) visit: patient alive and no isolation of MSSA in blood culture or at another sterile site from day 8 until TOC (12 weeks after randomisation).We assume a rate of treatment success of 74% in the cloxacillin group. Accepting alpha risk of 0.05 and beta risk of 0.2 in a two-sided test, 183 subjects will be required in each of the control and experimental groups to obtain statistically significant difference of 12% (considered clinically significant).

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Ethics Committee of Bellvitge University Hospital (AC069/18) and from the Spanish Medicines and Healthcare Product Regulatory Agency (AEMPS, AC069/18), and is valid for all participating centres under existing Spanish legislation. The results will be presented at international meetings and will be made available to patients and funders.

TRIAL REGISTRATION NUMBER

The protocol has been approved by AEMPS with the Trial Registration Number EudraCT 2018-001207-37. ClinicalTrials.gov Identifier: NCT03959345; Pre-results.

Characteristics of infective endocarditis in a cancer population

Background

Infective endocarditis (IE) is more common in patients with cancer as compared with the general population. Due to an immunocompromised state, the need for invasive procedures, hypercoagulability and the presence of indwelling catheters, patients with cancer are particularly predisposed to the development of IE.

Objectives

Limited information exists about IE in patients with cancer. We aimed to evaluate the characteristics of patients with cancer and IE at our tertiary care centre, including a comparison of the microorganisms implicated and their association with mortality.

Methods

A retrospective chart review of patients with cancer who had echocardiography for suspicion of endocarditis was conducted. A total of 56 patients with a confirmed diagnosis of cancer and endocarditis, based on the modified Duke criteria, were included in the study. Baseline demographics, risk factors for developing IE, echocardiography findings, microbiology and mortality data were analysed.

Results

Following the findings of vegetations by echocardiography, the median survival time was 8.5 months. Staphylococcus aureus was the most common organism identified as causing endocarditis. The mitral and aortic valves were the most commonly involved sites of endocarditis. Patients with S. aureus endocarditis (SAE) had a significantly poorer survival when compared with patients without SAE (p=0.0217) over the 12-month period from diagnosis of endocarditis.

Conclusions

Overall survival of patients with cancer and endocarditis is poor, with a worse outcome in patients with SAE.

Incidence and burden of Staphylococcus aureus infection after orthopedic surgeries

OBJECTIVE

To assess the 180-day incidence of Staphylococcus aureus infections following orthopedic surgeries using microbiology cultures.

DESIGN

Retrospective observational epidemiology study.

SETTING

National administrative hospital database.

PATIENTS

Adult patients with an elective admission undergoing orthopedic surgeries in the inpatient and hospital-based outpatient settings discharged between July 1, 2010, and June 30, 2015.

METHODS

Patients were identified from 181 hospitals reporting microbiology results to the Premier Healthcare Database. Orthopedic surgeries were defined using International Classification of Disease, Ninth Revision, Clinical Modification (ICD-9-CM) procedure and current procedural terminology (CPT) codes. Microbiology cultures and ICD-9/10 diagnosis codes identified surgical site infections (SSIs), bloodstream infections (BSIs), and other infections associated postoperatively (eg, respiratory and urinary tract infections).

RESULTS

Among 359,268 inpatient orthopedic surgical encounters, the S. aureus infection incidence was 1.13%: SSI, 0.68%; BSI, 0.28%; and other types, 0.17%. Among 292,011 outpatient encounters, the S. aureus incidence was 0.78%: SSI, 0.55%; BSI, 0.12%; and other types, 0.11%. Methicillin-resistant S. aureus (MRSA) infections accounted for 46% and 44% in the respective settings. Plastic/hand-limb reattachment and amputation had the highest overall S. aureus incidence in both settings. S. aureus was the most commonly isolated microorganism among culture-confirmed SSIs (48.0%) and BSIs (35.0%), followed by other Enterobacteriaceae (14.0%) for SSIs and Escherichia spp (12.5%) for BSIs.

CONCLUSIONS

These findings suggest that S. aureus infections continue to be an important contributor to the burden of postoperative infections after inpatient and outpatient orthopedic procedures.

Ceftriaxone as an Alternative Therapy for the Treatment of Methicillin-Susceptible Staphylococcus aureus Bacteremia after Initial Clearance of Bloodstream Infection

Introduction

Staphylococcus spp. represent the leading cause of hospital-acquired infections and second-most frequent pathogen in bloodstream infections. Methicillin-susceptible S. aureus (MSSA) comprise approximately half of all S. aureus isolates. Standard-of-care therapies (SOCTs) display high treatment success but require frequent dosing, are problematic in penicillin allergic patients, and are nephrotoxic. Ceftriaxone may represent an alternative treatment option.

Methods

Adult patients hospitalized from January 2015 through June 2016 with positive MSSA blood cultures and treated with SOCT or ceftriaxone for ≥48 hours were included. Exclusion criteria were receipt of vancomycin or concomitant systemic antimicrobials with activity against MSSA, polymicrobial infections, and pregnant patients. Additional data collected included demographics, source/site of infection, and treatment. The primary endpoint was clinical cure (normalization of white blood cell count and temperature within 7 days and clearance of bloodstream within 7 days). Readmission within 60 days, length of stay, and discharge disposition were collected.

Results

A total of 43 patients were included: 23 receiving SOCT and 20 receiving ceftriaxone group. Sixteen patients received SOCT prior to ceftriaxone while 4 patients were initiated on ceftriaxone. Clinical cure was observed in 18/23 (78%) and 10/20 (50%), respectively (P=0.052). Clinical failure was driven by leukocytosis despite clearance of their bloodstream infection in 3/23 (13%) SOCT group compared to 8/20 (40%) in the ceftriaxone group (P=0.043). Six patients (SOCT: 2, ceftriaxone: 4; p=0.669) had infection-related readmissions, and 1 death per group was observed.

Conclusion

Ceftriaxone poses a reasonable alternative to consider for MSSA bacteremia when cost and feasibility are concerns for outpatient parenteral therapy after initial clearance of bloodstream infections.

C-reactive protein predicts complications in community-associated S. aureus bacteraemia: a cohort study

Background

Staphylococcus aureus (S. aureus) bacteraemia is increasingly acquired from community settings and is associated with a mortality rate of up to 40% following complications. Identifying risk factors for complicated S. aureus bacteraemia would aid clinicians in targeting patients that benefit from expedited investigations and escalated care.

Methods

In this prospective observational cohort study, we aimed to identify risk factors associated with a complicated infection in community-onset S. aureus bacteraemia. Potential risk factors were collected from electronic medical records and included: - patient demographics, symptomology, portal of entry, and laboratory results.

Results

We identified several potential risk factors using univariate analysis. In a multiple logistic regression model, age, haemodialysis, and entry point from a diabetic foot ulcer were all significantly protective against complications. Conversely, an unknown entry point of infection, an entry point from an indwelling medical device, and a C-reactive protein concentration of over 161 mg/L on the day of admission were all significantly associated with complications.

Conclusions

We conclude that several factors are associated with complications including already conducted laboratory investigations and portal of entry of infection. These factors could aid the triage of at-risk patients for complications of S. aureus bacteraemia.

Sepsis in Immunocompromised Patients Without Human Immunodeficiency Virus

Sepsis remains among the most common complications from infectious diseases worldwide. The morbidity and mortality rates associated with sepsis range from 20% to 50%. The advances in care for patients with an immunocompromised status have been remarkable over the last 2 decades, but sepsis continues to be a major cause of death in this population Immunocompromised patients who are recipients of a solid organ or hematopoietic stem cell transplant are living longer with a better quality of life. However, some of these patients need lifelong treatment with immunosuppressive medications to maintain their transplant status. A consequence of the need for this permanent immunosuppression is the high risk of opportunistic, community, and hospital-acquired infections, all of which can lead to sepsis. In addition, the detection of serious infections may be more challenging owing to patients' lower ability to mount the clinical symptoms that usually accompany sepsis. This article provides an update on the current knowledge of sepsis in immunocompromised patients without human immunodeficiency virus. It reviews the most pertinent causes of sepsis in this population, and addresses the specific diagnostic and therapeutic challenges in neutropenia and solid organ and hematopoietic stem cell transplantation.

Management of Staphylococcus aureus Bloodstream Infections

Staphylococcus aureus bloodstream infections are associated with a high morbidity and mortality. Nevertheless, significance of a positive blood culture with this pathogen is often underestimated or findings are misinterpreted as contamination, which can result in inadequate diagnostic and therapeutic consequences. We here review and discuss current diagnostic and therapeutic key elements and open questions for the management of Staphylococcus aureus bloodstream infections.

Validation of VIRSTA and Predicting Risk of Endocarditis Using a Clinical Tool (PREDICT) Scores to Determine the Priority of Echocardiography in Patients With Staphylococcus aureus Bacteremia

Background

Infective endocarditis (IE) secondary to Staphylococcus aureus bacteremia (SAB) has high morbidity and mortality. The systematic use of echocardiography in SAB is controversial. We aimed to validate VIRSTA and Predicting Risk of Endocarditis Using a Clinical Tool (PREDICT) scores for predicting the risk of IE in Colombian patients with SAB and, consequently, to determine the need for echocardiography.

Methods

Cohort of patients hospitalized with SAB in 2 high complexity institutions in Medellin, Colombia, between 2012 and 2018. The diagnosis of IE was established based on the modified Duke criteria. The VIRSTA and PREDICT scores were calculated from the clinical records, and their operational performance was calculated.

Results

The final analysis included 922 patients, 62 (6.7%) of whom were diagnosed with IE. The frequency of IE in patients with a negative VIRSTA scale was 0.44% (2/454). The frequency of IE in patients with a negative PREDICT scale on day 5 was 4.8% (30/622). The sensitivity and negative predictive value (NPV) of the VIRSTA scale was 96.7% and 99.5%, respectively. For the PREDICT scale on day 5, the sensitivity and NPV were 51.6% and 95.1%, respectively. The discrimination, given by the area under the receiver operating characteristic curve, was 0.86 for VIRSTA and 0.64 for PREDICT.

Conclusions

In patients with negative VIRSTA, screening echocardiography may be unnecessary because of the low frequency of IE. In PREDICT-negative patients, despite the low frequency of IE, it is not safe to omit echocardiography.

Central venous catheter-related infections in hematology and oncology: 2020 updated guidelines on diagnosis, management, and prevention by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO)

Cancer patients frequently require central venous catheters for therapy and parenteral nutrition and are at high risk of central venous catheter-related infections (CRIs). Moreover, CRIs prolong hospitalization, cause an excess in resource utilization and treatment cost, often delay anti-cancer treatment, and are associated with a significant increase in mortality in cancer patients. We therefore summoned a panel of experts by the Infectious Diseases Working Party (AGIHO) of the German Society of Hematology and Medical Oncology (DGHO) and updated our previous guideline on CRIs in cancer patients. After conducting systematic literature searches on PubMed, Medline, and Cochrane databases, video- and meeting-based consensus discussions were held. In the presented guideline, we summarize recommendations on definition, diagnosis, management, and prevention of CRIs in cancer patients including the grading of strength of recommendations and the respective levels of evidence. This guideline supports clinicians and researchers alike in the evidence-based decision-making in the management of CRIs in cancer patients.

Current strategies for managing intestinal failure-associated liver disease

Introduction: Intestinal failure-associated liver disease (IFALD) refers to hepatic dysfunction that results from prolonged parenteral nutrition (PN) use. IFALD is multifactorial in origin and remains a major cause of morbidity and mortality. Prior to 2004, IFALD was associated with mortality as high as 90% in infants who remained on PN greater than 1 year. The advent of new strategies for intravenous lipid emulsion (ILE) administration and improved catheter care now allow many patients to remain on PN and recover from this once fatal condition. Several additional treatment modalities are often used to further improve outcomes for IFALD patients and they are reviewed here.Areas covered: The etiology of IFALD is presented, as well as the rationale behind the use of ILEs that contain fish oil. Other management strategies are addressed, including the effects of several pharmacologic and nutritional interventions.Expert opinion: Like its etiology, the management of IFALD is multifactorial. Prompt recognition of patients at risk, avoiding macronutrient excess, and preventing central line associated bloodstream infections will improve outcomes. In patients who develop IFALD, the use of fish oil monotherapy seems to be efficacious. The most effective intervention, however, continues to be discontinuation of PN and achieving full enteral feedings.

Clinical Characteristics and Outcomes of S. Aureus Bacteremia in Patients Receiving Total Parenteral Nutrition

Background: Patients on total parenteral nutrition (TPN) are at risk of developing central line-associated infections. Specifically, Staphylococcus aureus bacteremia (SAB) is feared for its high complication rates. This prospective cohort study compares characteristics, clinical course and outcome of SAB in patients with and without TPN support. Methods: Clinical and microbiological data from all patients with positive blood cultures for S. aureus from two facilities, including our referral center for TPN support, were retrieved (period 2013-2020). Primary outcome was overall mortality, and included survival analysis using a multivariate Cox regression model. Secondary outcomes comprised a comparison of clinical characteristics and outcomes between both patient groups and analysis of factors associated with complicated outcome (e.g., endocarditis, deep-seated foci, relapse and death) in patients on TPN specifically. Results: A total of 620 SAB cases were analyzed, of which 53 cases received TPN at the moment the blood culture was taken. Patients in the TPN group were more frequently female, younger and had less comorbidity (p < 0.001). In-hospital death and overall mortality were significantly lower in TPN patients (4% vs. 18%, p = 0.004 and 10% vs. 34%, p < 0.001, respectively). Positive follow-up blood cultures, delayed onset of therapy and previous catheter problems were associated with a higher incidence of complicated SAB outcome in patients on TPN. Conclusion: Our data show that patients on TPN have a milder course of SAB with lower mortality rates compared to non-TPN SAB patients.

Prevalence of infective endocarditis in patients with positive blood cultures: a Danish nationwide study

AIMS

Increasing attention has been given to the risk of infective endocarditis (IE) in patients with certain blood stream infections (BSIs). Previous studies have been conducted on selected patient cohorts, yet unselected data are sparse. We aimed to investigate the prevalence of IE in BSIs with bacteria typically associated with IE.

METHODS AND RESULTS

By crosslinking nationwide registries from 2010 to 2017, we identified patients with BSIs typically associated with IE: Enterococcus faecalis (E. faecalis), Staphylococcus aureus (S. aureus), Streptococcus spp., and coagulase negative staphylococci (CoNS) and examined the concurrent IE prevalence. A trend test was used to examine temporal changes in the prevalence of IE. In total 69 021, distributed with 15 350, 16 726, 19 251, and 17 694 BSIs were identified in the periods of 2010-2011, 2012-2013, 2014-2015, and 2016-2017, respectively. Patients with E. faecalis had the highest prevalence of IE (16.7%) followed by S. aureus (10.1%), Streptococcus spp. (7.3%), and CoNS (1.6%). Throughout the study period, the prevalence of IE among patients with E. faecalis and Streptococcus spp. increased significantly (P = 0.0005 and P = 0.03, respectively). Male patients had a higher prevalence of IE for E. faecalis, Streptococcus spp., and CoNS compared with females. A significant increase in the prevalence of IE was seen for E. faecalis, Streptococcus spp., and CoNS with increasing age.

CONCLUSION

For E. faecalis BSI, 1 in 6 had IE, for S. aureus BSI 1 in 10 had IE, and for Streptococcus spp. 1 in 14 had IE. Our results suggest that screening for IE seems reasonable in patients with E. faecalis BSI, S. aureus BSI, or Streptococcus spp. BSI.

Management of fever and neutropenia in the adult patient with acute myeloid leukemia

INTRODUCTION

Febrile neutropenia represents one of the most common treatment-associated complications in the management of acute myeloid leukemia (AML) and is considered an oncologic emergency. Rapid and detailed workup as well as the initiation of empiric broad-spectrum antibiotic therapy are critical to avoid sepsis and to reduce mortality. Although a definitive source of infection is frequently not identified, the severely immunosuppressed status of the AML patient undergoing cytotoxic therapy results in a high risk for a wide array of bacterial, fungal, and viral etiologies.

AREAS COVERED

The authors herein review the diagnostic and therapeutic approach to the neutropenic leukemia patient based on the current knowledge. Special consideration is given to the rapidly changing therapeutic landscape in AML, creating new challenges in the management of infectious complications.

EXPERT OPINION

Multidrug-resistant organisms pose a major challenge in the management of neutropenic fever patients with hematologic malignancies - including AML. Future directions to improve outcomes demand innovative treatment approaches as well as advances in biomarker research to facilitate diagnosis and disease monitoring. Recent achievements in AML-targeted therapy led to an increased incidence of differentiation syndrome, a potentially life-threatening side effect that frequently resembles clinical infection and requires prompt recognition and aggressive intervention.

Clinical impact of early reinsertion of a central venous catheter after catheter removal in patients with catheter-related bloodstream infections

OBJECTIVE

Early replacement of a new central venous catheter (CVC) may pose a risk of persistent or recurrent infection in patients with a catheter-related bloodstream infection (CRBSI). We evaluated the clinical impact of early CVC reinsertion after catheter removal in patients with CRBSIs.

METHODS

We conducted a retrospective chart review of adult patients with confirmed CRBSIs in 2 tertiary-care hospitals over a 7-year period.

RESULTS

To treat their infections, 316 patients with CRBSIs underwent CVC removal. Among them, 130 (41.1%) underwent early CVC reinsertion (≤3 days after CVC removal), 39 (12.4%) underwent delayed reinsertion (>3 days), and 147 (46.5%) did not undergo CVC reinsertion. There were no differences in baseline characteristics among the 3 groups, except for nontunneled CVC, presence of septic shock, and reason for CVC reinsertion. The rate of persistent CRBSI in the early CVC reinsertion group (22.3%) was higher than that in the no CVC reinsertion group (7.5%; P = .002) but was similar to that in the delayed CVC reinsertion group (17.9%; P > .99). The other clinical outcomes did not differ among the 3 groups, including rates of 30-day mortality, complicated infection, and recurrence. After controlling for several confounding factors, early CVC reinsertion was not significantly associated with persistent CRBSI (OR, 1.59; P = .35) or 30-day mortality compared with delayed CVC reinsertion (OR, 0.81; P = .68).

CONCLUSIONS

Early CVC reinsertion in the setting of CRBSI may be safe. Replacement of a new CVC should not be delayed in patients who still require a CVC for ongoing management.

Minimising Blood Stream Infection: Developing New Materials for Intravascular Catheters

Catheter related blood stream infection is an ever present hazard for those patients requiring venous access and particularly for those requiring long term medication. The implementation of more rigorous care bundles and greater adherence to aseptic techniques have yielded substantial reductions in infection rates but the latter is still far from acceptable and continues to place a heavy burden on patients and healthcare providers. While advances in engineering design and the arrival of functional materials hold considerable promise for the development of a new generation of catheters, many challenges remain. The aim of this review is to identify the issues that presently impact catheter performance and provide a critical evaluation of the design considerations that are emerging in the pursuit of these new catheter systems.

Early Oral Switch to Linezolid for Low-risk Patients With Staphylococcus aureus Bloodstream Infections: A Propensity-matched Cohort Study

BACKGROUND

Oral switch to linezolid is a promising alternative to standard parenteral therapy (SPT) in Staphylococcus aureus bacteremia (SAB).

METHODS

We conducted a prospective cohort study of all adult cases of SAB between 2013 and 2017 in a Spanish university hospital. We compared the efficacy, safety, and length of hospital stay of patients receiving SPT and those where SPT was switched to oral linezolid between days 3 and 9 of treatment until completion. We excluded complicated SAB and osteoarticular infections. A k-nearest neighbor algorithm was used for propensity score matching with a 2:1 ratio.

RESULTS

After propensity score matching, we included 45 patients from the linezolid group and 90 patients from the SPT group. Leading SAB sources were catheter related (49.6%), unknown origin (20.0%), and skin and soft tissue (17.0%). We observed no difference in 90-day relapse between the linezolid group and the SPT group (2.2% vs 4.4% respectively; P = .87). No statistically significant difference was observed in 30-day all-cause mortality between the linezolid group and the SPT group (2.2% vs 13.3%; P = .08). The median length of hospital stay after onset was 8 days in the linezolid group and 19 days in the SPT group (P < .01). No drug-related events leading to discontinuation were noted in the linezolid group.

CONCLUSIONS

Treatment of SAB in selected low-risk patients with an oral switch to linezolid between days 3 and 9 of treatment until completion yielded similar clinical outcomes as SPT, allowing earlier discharge from the hospital.

Do written diagnosis-treatment recommendations on microbiological test reports improve the management of Staphylococcus aureus bacteremia? A single-center, retrospective, observational study

The objective of this study was to assess the impact of microbiological test reports that provide specific written recommendations on the appropriate management of Staphylococcus aureus bacteremia (SAB). We performed a retrospective analysis of laboratory and clinical data of all SAB patients treated at one German University hospital, 2012-2015. Among 467 included patients, methicillin-resistant S. aureus (MRSA) accounted for 15.2% of all SAB cases. All-cause in-hospital mortality was 25.2%, and was significantly elevated in individuals aged >55 years, in MRSA bacteremia and if the source of infection remained unidentified. Focus identification was achieved in 71.1%, with the most prevalent foci being catheter-associated bloodstream infection (23.1%), soft tissue infection (15.4%), osteomyelitis (5.1%) and endocarditis (4.9%). Standardized written recommendations on microbiological test reports led to a significant increase of transesophageal echocardiography, additional imaging studies for focus identification and more frequent follow-up blood cultures, but no significant effect on mortality was observed.

Bactericidal Capacity of a Heterogeneous TiO2/ZnO Nanocomposite against Multidrug-Resistant and Non-Multidrug-Resistant Bacterial Strains Associated with Nosocomial Infections

The surge of medical devices associated with nosocomial infection (NI) cases, especially by multidrug-resistant (MDR) bacterial strains, is one of the pressing issues of present health care systems. Metal oxide nanoparticles (MNPs) have become promising antibacterial agents against a wide range of bacterial strains. This work study is on the bactericidal capacity of heterogeneous TiO₂/ZnO nanocomposites with different weight percentages and concentrations against common MDR and non-MDR bacterial strains. The profiles on disk diffusion, minimum inhibitory concentration, minimum bactericidal concentration, tolerance determination, time-kill, and biofilm inhibition assay were determined after 24 h of direct contact with the nanocomposite samples. Findings from this work revealed that the heterogeneous TiO₂/ZnO nanocomposite with a 25T75Z weight ratio showed an optimal tolerance ratio against Gram-positive and -negative bacteria, indicating their bactericidal capacity. Further observation suggests that higher molar ratio of Zn²⁺ may possibly involve generation of active ion species that enhance bactericidal effect against Gram-positive bacterial strains, especially for the MDR strains. Nano-based technology using MNPs may provide a promising solution for the prevention and control of NIs. Further work on biocompatibility and cytotoxicity profiles of this nanocomposite are needed.

Different Types of Coagulase Are Associated With 28-Day Mortality in Patients With Staphylococcus aureus Bloodstream Infections

Background:Staphylococcus aureus (S. aureus), a leading cause of bacteremia and infective endocarditis, exploits the human coagulation system by using a wide range of specific virulence factors. However, the impact of these host-pathogen interactions on the outcome of patients with Staphylococcus aureus bacteremia (SAB) remains unclear.

Methods: A total of 178 patients with S. aureus bacteremia were included and analyzed regarding bacterial factors (coa gene size, vWbp, clfA, clfB, fnbA, fnbB, fib) and clinical parameters. A stepwise multivariate Cox regression model and a Partitioning Around Medoids (PAM) cluster algorithm were used for statistical analysis.

Results: Patients' risk factors for 28-day mortality were creatinine (OR 1.49, p < 0.001), age (OR 1.9, p < 0.002), fibrinogen (OR 0.44, p < 0.004), albumin (OR 0.63, p < 0.02), hemoglobin (OR 0.59, p < 0.03), and CRP (OR 1.72, p < 0.04). Five distinct bacterial clusters with different mortality rates were unveiled, whereof two showed a 2-fold increased mortality and an accumulation of specific coagulase gene sizes, 547-base pairs and 660-base pairs.

Conclusions: Based on the data obtained in the present study an association of coagulase gene size and fib regarding 28-day mortality was observed in patients with S. aureus bloodstream infections. Further animal and prospective clinical studies are needed to confirm our preliminary findings.

Staphylococcus pseudintermedius catheter-related bloodstream infection after exposure to domestic dogs and a cat

We report a case of a catheter-related bloodstream infection due to oxacillin-susceptible Staphylococcus pseudintermedius in a patient receiving haemodialysis who possibly acquired the organism from her pets. Because of persistent bacteremia and the organism's ability to form biofilm, catheter removal and antimicrobial therapy were indicated to attain source control. Both clinical and microbiological cure were confirmed. Catheter care education should include information about pet exposure and the possibility of zoonotic infections.

Metastatic infection during Staphylococcus aureus bacteremia

Staphylococcus aureus causes various infections, including skin and soft tissue infections and pneumonia via both, community-associated and nosocomial infection. These infectious diseases can lead to bacteremia, and may subsequently result in metastatic infections in several cases. Metastatic infections are critical complications in patients with S. aureus bacteremia, since the optimal duration of the antimicrobial treatment differs in patients with and without metastatic infection. Notably, two weeks of antimicrobial treatment is recommended in case of uncomplicated S. aureus bacteremia, whereas in patients with S. aureus bacteremia-associated endocarditis or vertebral osteomyelitis, six weeks of antimicrobial administration is vital. In addition, misdiagnosis or insufficient treatment in metastatic infection is associated with poor prognosis, functional disability, and relapse. Although echocardiography is recommended to examine endocarditis in the patients with S. aureus bacteremia, it remains unclear which patients should undergo additional examinations, such as CT and MRI, to detect the presence of other metastatic infections. Clinical studies have revealed that permanent foreign body and persistent bacteremia are predictive factors for metastatic infections, and experimental studies have demonstrated that the virulence factors of S. aureus, such as fnbA and clfA, are associated with endocarditis; however, these factors are not proven to increase the risk of metastatic infections. In this review, we assessed the incidence, predictive factors, diagnosis, and treatment for metastatic infections during S. aureus bacteremia.

Risk Factors for Complications in Children with Staphylococcus aureus Bacteremia

OBJECTIVES

To determine risk factors for complications in children with Staphylococcus aureus (S aureus) bacteremia, including methicillin resistance.

STUDY DESIGN

Single center, retrospective cohort study of children ≤18 years of age hospitalized with S aureus bacteremia. We compared clinical characteristics and outcomes between those with methicillin-sensitive S aureus (MSSA) and methicillin-resistant S aureus (MRSA) bacteremia. Multivariate regression models identified risk factors associated with developing complications and with longer duration of bacteremia.

RESULTS

We identified 394 episodes of S aureus bacteremia, 279 (70.8%) with MSSA, and 115 (29.2%) with MRSA. Primary site of infection was catheter-related in 34%, musculoskeletal in 30%, skin/soft tissue in 10.2%, pneumonia in 6.4%, and endovascular in 6.6%. Eight children (2.0%) died within 30 days because of S aureus bacteremia, 15 (3.5%) had recurrence within 30 days, and 38 (9.6%) had complications including septic emboli or a metastatic focus of infection. Methicillin resistance was associated with development of a complication (aOR 3.31; 95% CI 1.60-6.85), and catheter-related infections were less likely to be associated with a complication (aOR 0.40; 95% CI 0.15-1.03). In a Poisson regression analysis on duration of bacteremia, methicillin resistance, musculoskeletal infection, endovascular infection, black race, and delayed intervention for source control were significantly associated with longer duration of bacteremia.

CONCLUSIONS

In this cohort of children with S aureus bacteremia, MRSA infections ere associated with longer duration of bacteremia and a higher likelihood of complications.

Diagnosis and treatment of catheter-related bloodstream infection: Clinical guidelines of the Spanish Society of Infectious Diseases and Clinical Microbiology and (SEIMC) and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC)

Catheter-related bloodstream infections (CRBSI) constitute an important cause of hospital-acquired infection associated with morbidity, mortality, and cost. The aim of these guidelines is to provide updated recommendations for the diagnosis and management of CRBSI in adults. Prevention of CRBSI is excluded. Experts in the field were designated by the two participating Societies (the Spanish Society of Infectious Diseases and Clinical Microbiology and [SEIMC] and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units [SEMICYUC]). Short-term peripheral venous catheters, non-tunneled and long-term central venous catheters, tunneled catheters and hemodialysis catheters are covered by these guidelines. The panel identified 39 key topics that were formulated in accordance with the PICO format. The strength of the recommendations and quality of the evidence were graded in accordance with ESCMID guidelines. Recommendations are made for the diagnosis of CRBSI with and without catheter removal and of tunnel infection. The document establishes the clinical situations in which a conservative diagnosis of CRBSI (diagnosis without catheter removal) is feasible. Recommendations are also made regarding empirical therapy, pathogen-specific treatment (coagulase-negative staphylococci, Staphylococcus aureus, Enterococcus spp., Gram-negative bacilli, and Candida spp.), antibiotic lock therapy, diagnosis and management of suppurative thrombophlebitis and local complications.

Indian Antimicrobial Prescription Guidelines in Critically Ill Immunocompromised Patients

How to cite this article: Kulkarni AP, Sengar M, Chinnaswamy G, Hegde A, Rodrigues C, Soman R, Khilnani GC, Ramasubban S, Desai M, Pandit R, Khasne R, Shetty A, Gilada T, Bhosale S, Kothekar A, Dixit S, Zirpe K, Mehta Y, Pulinilkunnathil JG, Bhagat V, Khan MS, Narkhede AM, Baliga N, Ammapalli S, Bamne S, Turkar S, Bhat KV, Choudhary J, Kumar R, Divatia JV. Indian Journal of Critical Care Medicine 2019;23(Suppl 1): S64-S96.

Benefit of Echocardiography in Patients With Staphylococcus aureus Bacteremia at Low Risk of Endocarditis

Background

The risk of endocarditis among patients with Staphylococcus aureus bacteremia is not uniform, and a number of different scores have been developed to identify patients whose risk is less than 5%. The optimal echocardiography strategy for these patients is uncertain.

Methods

We used decision analysis and Monte Carlo simulation using input parameters taken from the existing literature. The model examined patients with S aureus bacteremia whose risk of endocarditis is less than 5%, generally those with nosocomial or healthcare-acquired bacteremia, no intracardiac prosthetic devices, and a brief duration of bacteremia. We examined 6 echocardiography strategies, including the use of transesophageal echocardiography, transthoracic echocardiography, both modalities, and neither. The outcome of the model was 90-day survival.

Results

The optimal echocardiography strategy varied with the risk of endocarditis and the procedural mortality associated with transesophageal echocardiography. No echocardiography strategy offered an absolute benefit in 90-day survival of more than 0.5% compared with the strategy of not performing echocardiography and treating with short-course therapy. Strategies using transesophageal echocardiography were never preferred if the mortality of this procedure was greater than 0.5%.

Conclusions

In patients identified to be at low risk of endocarditis, the choice of echocardiography strategy appears to exert a very small influence on 90-day survival. This finding may render test-treatment trials unfeasible and should prompt clinicians to focus on other, more important, management considerations in these patients.

Factors associated with recurrence and mortality in central line-associated bloodstream infections: a retrospective cohort study

Background

Central line-associated bloodstream infections (CLABSIs) are associated with increased mortality, hospital length of stay, and cost. Antimicrobial treatment guidelines for CLABSIs are primarily based on expert opinion. We hypothesized that shorter antimicrobial treatment duration is associated with decreased 60-day recurrence-free survival.

Methods

A retrospective cohort study of all adults with hospital-acquired CLABSIs (HA-CLABSIs) over 5 years at a single tertiary care academic hospital was performed. The time from the end of effective antimicrobial treatment until recurrence of infection or mortality, censored at 60 days after the end of antimicrobial treatment, represented the primary outcome. Effective antimicrobial treatment was defined as the administration of at least one antimicrobial to which the causative organism was sensitive.

Results

A total of 366 cases met eligibility criteria. The median Sequential Organ Failure Assessment (SOFA) score was 6 (interquartile range (IQR) 4–8). Patients were treated for a median of 15 (IQR 10–20) days with effective antimicrobials. The incidence of 60-day mortality or recurrence after completion of the antimicrobial course was 22.1% (81 patients). In a Cox proportional-hazards model, antimicrobial treatment duration (hazard ratio (HR) = 0.35; 95% confidence interval (CI) 0.26–0.48), SOFA score (HR = 1.16; 95% CI 1.09–1.22), and age (HR = 1.021; 95% CI = 1.004–1.037) were associated with mortality or recurrence. The effect of antimicrobial treatment duration appeared to plateau after 15 days.

Conclusions

Longer antimicrobial treatment duration in patients with HA-CLABSIs is associated with improved recurrence-free survival during the first 60 days after infection. This effect appears to plateau after 15 days of treatment. Prospective studies are needed to definitively determine the optimal antimicrobial treatment duration for CLABSIs.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2206-7) contains supplementary material, which is available to authorized users.

Catheter removal and outcomes of multidrug-resistant central-line-associated bloodstream infection

Central-line-associated bloodstream infections (CLABSIs) are responsible for ∼1/3 of all deaths from healthcare-associated infections in the United States. Of these, multidrug-resistant organisms (MDROs) are responsible for 20% to 67%. However, whether catheter removal affects clinical outcomes for MDRO CLABSIs has not been studied. Our objective was to determine the relationship between failure to remove a central venous catheter (CVC) and 30-day all-cause mortality in patients with MDRO CLABSIs. We used a retrospective cohort from Barnes-Jewish Hospital (1/1/2009-10/1/2015) to study patients with a multidrug-resistant Staphylococcus aureus, Enterococcus species, Enterobacteriaceae, Acinetobacter species, or Pseudomonas aeruginosa CLABSI. Risk factors for 30-day mortality, including catheter removal, were assessed for association with 30-day mortality using Cox proportional hazards models. The CLABSIs were assessed prospectively at the time of occurrence by infection prevention specialists. A total of 430 patients met inclusion criteria, 173 (40.2%) with Enterococcus, 116 (27.0%) Enterobacteriaceae, 81 (18.8%) S aureus, 44 (10.2%) polymicrobial, 11 (2.6%) P aeruginosa, and 5 (1.2%) Acinetobacter CLABSIs. Removal of a CVC occurred in 50.2% of patients, of which 4.2% died by 30 days (n = 9). For patients whose CVC remained in place, 45.3% died (n = 97). Failure to remove a CVC was strongly associated with 30-day all-cause mortality with a hazard ratio of 13.5 (6.8-26.7), P < .001. Other risk factors for 30-day mortality included patient comorbidities (cardiovascular disease, congestive heart failure, cirrhosis), and being in an intensive care unit at the time of MDRO isolation. Failure to remove a CVC was strongly associated with 30-day all-cause mortality for patients with MDRO CLABSIs in this single center retrospective cohort. This suggests that patients presenting with MDRO CLABSIs should all undergo CVC removal.

What risk of endocarditis is low enough to justify the omission of transoesophageal echocardiography in Staphylococcus aureus bacteraemia? A narrative review

BACKGROUND

Recent criteria which can identify patients with Staphylococcus aureus bacteraemia (SAB) who are at very low risk of endocarditis raise the question of whether transoesophageal echocardiography (TOE) is appropriate for these patients.

AIMS

To estimate the probability of occult endocarditis complicating SAB below which a TOE-guided treatment strategy no longer offers the best 180-day survival, and to examine the key uncertainties affecting this result.

SOURCES

Estimates of the parameters required to calculate the Pauker-Kassirer testing threshold were identified from studies published prior to 1 June 2017 using a composite search strategy that involved a systematic search for relevant controlled trials and guidelines, followed by a non-systematic iterative search of the observational literature.

CONTENT

Estimates of the necessary parameters were generally consistent across the literature with the exception of the procedural mortality of TOE. In our base-case scenario (TOE mortality 0.1%), the testing threshold for TOE in apparently uncomplicated SAB was a 1.1% probability of occult endocarditis. Sensitivity analyses revealed that the procedural mortality of TOE was a key uncertainty affecting estimates of the testing threshold.

IMPLICATIONS

None of the available clinical tools can place patients with SAB below this probability of endocarditis with 95% confidence. Future work in this area should concentrate on improving the precision of these tools and on exploring the value of alternative echocardiography strategies. In addition, a better understanding of the harms of TOE is required to ensure that recommendations regarding the role of this investigation in the management of patients with SAB are appropriate.

Infection of totally implantable venous access devices: A review of the literature

Totally implantable venous access devices, or ports, are essential in the therapeutic management of patients who require long-term intermittent intravenous therapy. Totally implantable venous access devices guarantee safe infusion of chemotherapy, blood transfusion, parenteral nutrition, as well as repeated blood samples. Minimizing the need for frequent vascular access, totally implantable venous access devices also improve the patient's quality of life. Nonetheless, totally implantable venous access devices are not free from complications. Among those, infection is the most relevant, affecting patients' morbidity and mortality-both in the hospital or outpatient setting-and increasing healthcare costs. Knowledge of pathogenesis and risk factors of totally implantable venous access device-related infections is crucial to prevent this condition by adopting proper insertion bundles and maintenance bundles based on the best available evidence. Early diagnosis and prompt treatment of infection are of paramount importance. As a totally implantable venous access device-related infection occurs, device removal or a conservative approach should be chosen in treating this complication. For both prevention and therapy, antimicrobial lock is a major matter of controversy and a promising field for future clinical studies. This article reviews current evidences in terms of epidemiology, pathogenesis and risk factors, diagnosis, prevention, and treatment of totally implantable venous access device-related infections.

Salvage Strategy for Long-Term Central Venous Catheter-Associated Staphylococcus aureus Infections in Children

Introduction: Current international guidelines strongly recommend catheter removal in case of S. aureus central line-associated bloodstream infection (CLASBI), but a catheter salvage strategy may be considered in children given age-related specificities. No data is available regarding the outcome of this strategy in children. This study aims to evaluate catheter salvage strategy in children with S. aureus CLABSI, and to determine treatment failure rates and associated risk factors. Methods: We retrospectively analyzed data for all children <18 years having S. aureus CLABSI on a long-term central venous catheter in a tertiary hospital from 2010 to 2014. We defined catheter salvage strategy as a central venous catheter left in place ≥3 days after initiation of empiric treatment for suspected bacteremia, and catheter salvage strategy failure as the persistence or relapse of bacteremia with a S. aureus strain harboring the same antibiotic susceptibility pattern, or the occurrence or the worsening of local or systemic infectious complication between 72 h and 28 days after the first positive blood culture. Results: During the study period, 49 cases of S. aureus CLABSI on long-term central venous catheters were observed in 41 children (including 59% with long-term parenteral nutrition) and 6 (15%) isolates were resistant to methicillin. A catheter salvage strategy was chosen in 37/49 (76%) cases and failed in 12/37 (32%) cases. Initial presence of bloodstream co-infection, serum concentration of vancomycin under the targeted value and inadequate empiric treatment were significantly associated with catheter salvage therapy failure. Conclusions: The catheter salvage strategy of S. aureus CLABSI on a long-term central venous catheter was frequent in the studied hospital and failed only in one third of cases.

Criteria for Identifying Patients With Staphylococcus aureus Bacteremia Who Are at Low Risk of Endocarditis: A Systematic Review

This systematic review examines the methods and results of recent studies reporting clinical criteria able to identify patients with Staphylococcus aureus bacteremia who are at very low risk of endocarditis. We searched PubMed, EMBASE, and the Cochrane Collaboration CENTRAL database for articles published after March 1994 using a combination of MeSH and free text search terms for S. aureus AND bacteremia AND endocarditis. Studies were included if they presented a combination of clinical and microbiological criteria with a negative likelihood ratio of ≤0.20 for endocarditis. We found 8 studies employing various criteria and reference standards whose criteria were associated with negative likelihood ratios between 0.00 and 0.19 (corresponding to 0%-5% risk of endocarditis at 20% background prevalence). The benefit of echocardiography for patients fulfilling these criteria is uncertain.