Ciprofloxacin vs an aminoglycoside in combination with a beta-lactam for the treatment of febrile neutropenia: a meta-analysis of randomized controlled trials

WHO's essential medicines and AWaRe: recommendations on first- and second-choice antibiotics for empiric treatment of clinical infections

The WHO Model List of Essential Medicines (EML) prioritizes medicines that have significant global public health value. The EML can also deliver important messages on appropriate medicine use. Since 2017, in response to the growing challenge of antimicrobial resistance, antibiotics on the EML have been reviewed and categorized into three groups: Access, Watch, and Reserve, leading to a new categorization called AWaRe. These categories were developed taking into account the impact of different antibiotics and classes on antimicrobial resistance and the implications for their appropriate use. The 2023 AWaRe classification provides empirical guidance on 41 essential antibiotics for over 30 clinical infections targeting both the primary health care and hospital facility setting. A further 257 antibiotics not included on the EML have been allocated an AWaRe group for stewardship and monitoring purposes. This article describes the development of AWaRe, focussing on the clinical evidence base that guided the selection of Access, Watch, or Reserve antibiotics as first and second choices for each infection. The overarching objective was to offer a tool for optimizing the quality of global antibiotic prescribing and reduce inappropriate use by encouraging the use of Access antibiotics (or no antibiotics) where appropriate. This clinical evidence evaluation and subsequent EML recommendations are the basis for the AWaRe antibiotic book and related smartphone applications. By providing guidance on antibiotic prioritization, AWaRe aims to facilitate the revision of national lists of essential medicines, update national prescribing guidelines, and supervise antibiotic use. Adherence to AWaRe would extend the effectiveness of current antibiotics while helping countries expand access to these life-saving medicines for the benefit of current and future patients, health professionals, and the environment.

Inoculum-Based Dosing: A Novel Concept for Combining Time with Concentration-Dependent Antibiotics to Optimize Clinical and Microbiological Outcomes in Severe Gram Negative Sepsis

Certain classes of antibiotics show "concentration dependent" antimicrobial activity; higher concentrations result in increased bacterial killing rates, in contrast to "time dependent antibiotics", which show antimicrobial activity that depends on the time that antibiotic concentrations remain above the MIC. Aminoglycosides and fluoroquinolones are still widely used concentration-dependent antibiotics. These antibiotics are not hydrolyzed by beta-lactamases and are less sensitive to the inoculum effect, which can be defined as an increased MIC for the antibiotic in the presence of a relatively higher bacterial load (inoculum). In addition, they possess a relatively long Post-Antibiotic Effect (PAE), which can be defined as the absence of bacterial growth when antibiotic concentrations fall below the MIC. These characteristics make them interesting complementary antibiotics in the management of Multi-Drug Resistant (MDR) bacteria and/or (neutropenic) patients with severe sepsis. Global surveillance studies have shown that up to 90% of MDR Gram-negative bacteria still remain susceptible to aminoglycosides, depending on the susceptibility breakpoint (e.g., CLSI or EUCAST) being applied. This percentage is notably lower for fluoroquinolones but depends on the region, type of organism, and mechanism of resistance involved. Daily (high-dose) dosing of aminoglycosides for less than one week has been associated with significantly less nephro/oto toxicity and improved target attainment. Furthermore, higher-than-conventional dosing of fluoroquinolones has been linked to improved clinical outcomes. Beta-lactam antibiotics are the recommended backbone of therapy for severe sepsis. Since these antibiotics are time-dependent, the addition of a second concentration-dependent antibiotic could serve to quickly lower the bacterial inoculum, create PAE, and reduce Penicillin-Binding Protein (PBP) expression. Inadequate antibiotic levels at the site of infection, especially in the presence of high inoculum infections, have been shown to be important risk factors for inadequate resistance suppression and therapeutic failure. Therefore, in the early phase of severe sepsis, effort should be made to optimize the dose and quickly lower the inoculum. In this article, the authors propose a novel concept of "Inoculum Based Dosing" in which the decision for antibiotic dosing regimens and/or combination therapy is not only based on the PK parameters of the patient, but also on the presumed inoculum size. Once the inoculum has been lowered, indirectly reflected by clinical improvement, treatment simplification should be considered to further treat the infection.

Emerging challenges in the evaluation of fever in cancer patients at risk of febrile neutropenia in the era of COVID-19: a MASCC position paper

Patients with cancer are at higher risk of more severe COVID-19 infection and have more associated complications. The position paper describes the management of cancer patients, especially those receiving anticancer treatment, during the COVID-19 pandemic. Dyspnea is a common emergency presentation in patients with cancer with a wide range of differential diagnoses, including pulmonary embolism, pleural disease, lymphangitis, and infection, of which SARS-CoV-2 is now a pathogen to be considered. Screening interviews to determine whether patients may be infected with COVID-19 are imperative to prevent the spread of infection, especially within healthcare facilities. Cancer patients testing positive with no or minimal symptoms may be monitored from home. Telemedicine is an option to aid in following patients without potential exposure. Management of complications of systemic anticancer treatment, such as febrile neutropenia (FN), is of particular importance during the COVID-19 pandemic where clinicians aim to minimize patients' risk of infection and need for hospital visits. Outpatient management of patients with low-risk FN is a safe and effective strategy. Although the MASCC score has not been validated in patients with suspected or confirmed SARS-CoV-2, it has nevertheless performed well in patients with a range of infective illnesses and, accordingly, it is reasonable to expect efficacy in the clinical setting of COVID-19. Risk stratification of patients presenting with FN is a vital tenet of the evolving sepsis and pandemic strategy, necessitating access to locally formulated services based on MASCC and other national and international guidelines. Innovative oncology services will need to utilize telemedicine, hospital at home, and ambulatory care services approaches not only to limit the number of hospital visits but also to anticipate the complications of the anticancer treatments.

Evaluating guideline adherence regarding empirical vancomycin use in patients with neutropenic fever

OBJECTIVE

The purpose of this study was to evaluate the use of empirical vancomycin for patients with neutropenic fever (NF) with regard to adherence to treatment guidelines.

METHODS

Adult patients with a diagnosis of neutropenia, who met the definition of NF as per treatment guidelines, were identified. Use of vancomycin was evaluated as part of empirical therapy and again after 72h. Outcomes were assessed using descriptive statistics, the Chi-square or Fisher's exact test, and univariate exact logistic regression analyses.

RESULTS

Sixty-four patients were included. Overall, inappropriate empirical vancomycin use was observed in more than 30% of patients. Of 35 patients with indications for empirical vancomycin, only 68% received it. At 72h, appropriate vancomycin continuation, de-escalation, or discontinuation occurred in 21 of 33 patients. On univariate regression, hematological malignancy was associated with appropriate empirical vancomycin prescribing, whether initiating or withholding (odds ratio 4.0, 95% confidence interval 1.31-12.1). No variable was independently associated with inappropriate continuation at 72h.

CONCLUSIONS

There is poor guideline adherence to vancomycin prescribing as empirical therapy and at 72-h reassessment in patients with NF. Further efforts are needed to foster a more rational use of vancomycin in patients with NF.

Medical treatment of prosthetic vascular graft infections: Review of the literature and proposals of a Working Group

More than 400000 vascular grafts are inserted annually in the USA. Graft insertion is complicated by infection in 0.5-4% of cases. Vascular graft infections (VGIs) are becoming one of the most frequent prosthesis-related infections and are associated with considerable mortality, ranging from 10 to 25% within 30 days following the diagnosis. Treatment of VGI is based on urgent surgical removal of the infected graft followed by prolonged antibiotherapy. Data regarding the best antibiotherapy to use are lacking since no well designed trial to study antimicrobial treatment of VGI exists. Moreover, since VGIs demonstrate very specific pathophysiology, guidelines on other material-related infections or infective endocarditis treatment cannot be entirely applied to VGI. A French multidisciplinary group gathering infectious diseases specialists, anaesthesiologists, intensivists, microbiologists, radiologists and vascular surgeons was created to review the literature dealing with VGI and to make some proposals regarding empirical and documented antibiotic therapy for these infections. This article reveals these proposals.

[New KDIGO guidelines on acute kidney injury. Practical recommendations]

The incidence of acute kidney injury (AKI) in critically ill patients is very high and is associated with an increased morbidity and mortality. In 2012 the Kidney Disease: Improving Global Outcome (KDIGO) guidelines were published in which evidence-based practical recommendations are given for the evaluation and management of patients with AKI. The first section of the KDIGO guidelines deals with the unification of earlier consensus definitions and staging criteria for AKI. The subsequent sections of the guidelines cover the prevention and treatment of AKI as well as the management of renal replacement therapy (RRT) in patients with AKI. In each section the existing evidence is discussed and a specific treatment recommendation is given. The guidelines appreciates that there is insufficient evidence for many of the recommendations. As a specific pharmacological therapy is missing, an early diagnosis, aggressive hemodynamic optimization, tight volume control, and avoidance of nephrotoxic drugs are the only interventions to prevent AKI. If renal replacement therapy is required different modalities are available to provide an effective therapy with a low rate of adverse effects.

Once-daily, oral levofloxacin monotherapy for low-risk neutropenic fever in cancer patients: a pilot study in China

This pilot study assesses the safety and efficacy of once-daily, oral levofloxacin monotherapy in Chinese patients with low-risk febrile neutropenia. In this prospective, single-arm, open-label, multicenter clinical trial, 46 adult Chinese patients with solid tumors and low-risk febrile neutropenia were included. Patients received oral levofloxacin monotherapy (500 mg orally/day) until day 12, followed by 7 days of follow-up (day 19). Body temperature was measured three times per day. On days 2, 3, 5-7, 9, 12, and 19, disease symptoms and vital signs were recorded, adverse drug reactions were assessed, and blood samples were collected to determine the whole-blood cell count and the absolute neutrophil count. Blood cultures and chest radiographs were performed simultaneously until negative results were found. Oral levofloxacin was effective and well tolerated in 97.6% of patients irrespective of the cancer type and cause of fever. Body temperature began to decline in 24.4, 68.3, and 90.2% of patients, respectively, at 12, 24, and 48 h after initiating levofloxacin therapy. On days 5 and 7, 95.1 and 97.6% of the patients had complete defervescence, respectively. The median time for absolute neutrophil count recovery to at least 1500/mm after initiation of treatment was 3 days. Only one patient reported mild diarrhea. This pilot study showed that oral levofloxacin quickly and effectively reduced fever, initiated neutrophil recovery, and was well tolerated in Chinese low-risk febrile neutropenic patients with solid tumors. Further study is needed to compare patient data of levofloxacin with the standard amoxicillin/ciprofloxacin protocol in this population for both safety and efficacy.

How to treat severe infections in critically ill neutropenic patients?

Severe infections in neutropenic patient often progress rapidly leading to life-threatening organ dysfunction requiring admission to the Intensive Care Unit. Management strategies include early adequate appropriate empirical antimicrobial, early admission to ICU to avoid any delay in the diagnostic and therapeutic management of organ dysfunction. This review discusses the main clinical situations encountered in critically ill neutropenic patients. Specific diagnostic and therapeutic approaches have been proposed for acute respiratory failure, shock, neutropenic enterocolitis, catheter-related infections, cellulitis and primary bacteriemia. Non anti-infectious agents and recent advances will also be discussed. At present, most of large-scale studies and recommendations in neutropenic patients stem from hematological patients and will need further validation in ICU patients.

Risk of AKI with gentamicin as surgical prophylaxis

In 2009, the Scottish government issued a target to reduce Clostridium difficile infection by 30% in 2 years. Consequently, Scottish hospitals changed from cephalosporins to gentamicin for surgical antibiotic prophylaxis. This study examined rates of postoperative AKI before and after this policy change. The study population comprised 12,482 adults undergoing surgery (orthopedic, urology, vascular, gastrointestinal, and gynecology) with antibiotic prophylaxis between October 1, 2006, and September 30, 2010 in the Tayside region of Scotland. Postoperative AKI was defined by the Kidney Disease Improving Global Outcomes criteria. The study design was an interrupted time series with segmented regression analysis. In orthopedic patients, change in policy from cefuroxime to flucloxacillin (two doses of 1 g) and single-dose gentamicin (4 mg/kg) was associated with a 94% increase in AKI (P=0.04; 95% confidence interval, 93.8% to 94.3%). Most patients who developed AKI after prophylactic gentamicin had stage 1 AKI, but some patients developed persistent stage 2 or stage 3 AKI. The antibiotic policy change was not associated with a significant increase in AKI in the other groups. Regardless of antibiotic regimen, however, rates of AKI were high (24%) after vascular surgery, and increased steadily after gastrointestinal surgery. Rates could only be ascertained in 52% of urology patients and 47% of gynecology patients because of a lack of creatinine testing. These results suggest that gentamicin should be avoided in orthopedic patients in the perioperative period. Our findings also raise concerns about the increasing prevalence of postoperative AKI and failures to consistently measure postoperative renal function.

Febrile neutropenia in hematologic malignancies

Febrile neutropenia (FN) can occur at any time during the course of a malignancy, especially hematologic malignancies, from diagnosis to end-stage disease. The majority of FN episodes are typically confined to the period of initial diagnosis and active treatment. Because of suppressed inflammatory responses, fever is often the sole sign of infection. As FN is a true medical emergency, prompt identification of and intervention in FN can prolong survival and improve quality of life. This article reviews FN in the setting of hematologic malignancies, specifically myelodysplastic syndromes and acute leukemias, providing an overview of the definition of fever and neutropenia, diagnostic approach, categories of risk/risk assessment, management in patients at low and high risk, and prophylaxis of infections.

Initial use of one or two antibiotics for critically ill patients with community-acquired pneumonia: impact on survival and bacterial resistance

INTRODUCTION

Several guidelines recommend initial empirical treatment with two antibiotics instead of one to decrease mortality in community-acquired pneumonia (CAP) requiring intensive-care-unit (ICU) admission. We compared the impact on 60-day mortality of using one or two antibiotics. We also compared the rates of nosocomial pneumonia and multidrug-resistant bacteria.

METHODS

This is an observational cohort study of 956 immunocompetent patients with CAP admitted to ICUs in France and entered into a prospective database between 1997 and 2010.

RESULTS

Initial adequate antibiotic therapy was significantly associated with better survival (subdistribution hazard ratio (sHR), 0.63; 95% confidence interval (95% CI), 0.42 to 0.94; P = 0.02); this effect was strongest in patients with Streptococcus pneumonia CAP (sHR, 0.05; 95% CI, 0.005 to 0.46; p = 0.001) or septic shock (sHR: 0.62; 95% CI 0.38 to 1.00; p = 0.05). Dual therapy was associated with a higher frequency of initial adequate antibiotic therapy. However, no difference in 60-day mortality was found between monotherapy (β-lactam) and either of the two dual-therapy groups (β-lactam plus macrolide or fluoroquinolone). The rates of nosocomial pneumonia and multidrug-resistant bacteria were not significantly different across these three groups.

CONCLUSIONS

Initial adequate antibiotic therapy markedly decreased 60-day mortality. Dual therapy improved the likelihood of initial adequate therapy but did not predict decreased 60-day mortality. Dual therapy did not increase the risk of nosocomial pneumonia or multidrug-resistant bacteria.

Less is more: combination antibiotic therapy for the treatment of gram-negative bacteremia in pediatric patients

IMPORTANCE

Definitive combination antibiotic therapy with a β-lactam and an aminoglycoside for the treatment of gram-negative bacteremia is commonly prescribed in pediatric patients; however, its efficacy and toxicity relative to β-lactam monotherapy are unknown.

OBJECTIVE

To determine whether definitive combination antibiotic therapy affects mortality and nephrotoxicity in pediatric patients with gram-negative bacteremia.

DESIGN, SETTING, AND PARTICIPANTS

Retrospective cohort study including pediatric patients (aged ≤18 years) with gram-negative bacteremia hospitalized at the Johns Hopkins Children's Center between 2002 and 2011.

MAIN OUTCOMES AND MEASURES

Outcomes included 30-day mortality and nephrotoxicity classified according to the pediatric RIFLE (risk for renal dysfunction, injury to the kidney, failure of kidney function, loss of kidney function, and end-stage renal disease) criteria. To account for nonrandom assignment of combination therapy, propensity score weighting was combined with multivariable logistic regression to estimate the effect of combination therapy on mortality and nephrotoxicity.

RESULTS

Of the 879 eligible pediatric patients with bacteremia, 537 (61.1%) received combination therapy. After propensity score adjustment, baseline demographic and clinical characteristics between the groups were well balanced. There was no association between combination therapy and 30-day mortality (odds ratio, 0.98; 95% CI, 0.93-1.02; P = .27). There were 170 patients (19.3%) with evidence of acute kidney injury, including 135 (25.1%) and 35 (10.2%) in the combination therapy and monotherapy arms, respectively. Patients receiving combination therapy had approximately twice the odds of nephrotoxicity compared with those receiving monotherapy (odds ratio, 2.15; 95% CI, 2.09-2.21).

CONCLUSIONS AND RELEVANCE

The use of β-lactam monotherapy for gram-negative bacteremia in pediatric patients reduces subsequent nephrotoxicity without compromising survival.

Infection in neutropenic patients with cancer

Neutropenic fever sepsis syndromes are common among patients with cancer who are receiving intensive cytotoxic systemic therapy. Recognition of the syndromes and timely initial antibacterial therapy is critical for survival and treatment success. Outcomes are linked to myeloid reconstitution and recovery from neutropenia, control of active comorbidities, and appropriate treatment of the infections that underlie the sepsis syndrome. Hematologists and oncologists must be clear about the prognosis and treatment goals to work effectively with critical care physicians toward the best outcomes for patients with cancer who develop neutropenic sepsis syndromes.

Diagnosis, evaluation, and management of acute kidney injury: a KDIGO summary (Part 1)

Acute kidney injury (AKI) is a common and serious problem affecting millions and causing death and disability for many. In 2012, Kidney Disease: Improving Global Outcomes completed the first ever, international, multidisciplinary, clinical practice guideline for AKI. The guideline is based on evidence review and appraisal, and covers AKI definition, risk assessment, evaluation, prevention, and treatment. In this review we summarize key aspects of the guideline including definition and staging of AKI, as well as evaluation and nondialytic management. Contrast-induced AKI and management of renal replacement therapy will be addressed in a separate review. Treatment recommendations are based on systematic reviews of relevant trials. Appraisal of the quality of the evidence and the strength of recommendations followed the Grading of Recommendations Assessment, Development and Evaluation approach. Limitations of the evidence are discussed and a detailed rationale for each recommendation is provided.

Randomized controlled trial comparing ciprofloxacin and cefepime in febrile neutropenic patients with hematological malignancies

BACKGROUND

Ciprofloxacin (CPFX) is a potential alternative in patients with febrile neutropenia (FN) because of its activity against Gram-negative organisms. We conducted a non-inferiority, open-label, randomized controlled trial comparing intravenous CPFX and cefepime (CFPM) for FN patients with hematological malignancies.

METHODS

Patients aged from 15 to 79 years with an absolute neutrophil count of <0.500 × 10(9/)l were eligible, and were randomized to receive 300 mg of CPFX or 2g of CFPM every 12h. Initial treatment efficacy, overall response, and early toxicity were evaluated.

RESULTS

Fifty-one episodes were included in this trial, and 49 episodes (CPFX vs. CFPM: 24 vs. 25) were evaluated. Treatment efficacy at day 7 was significantly higher in the CFPM group (successful clinical response: nine with CPFX and 19 with CFPM; p=0.007). The response was better in high-risk patients with neutrophil counts of ≤ 0.100 × 10(9/)l (p=0.003). The overall response during the study period was similar between the CPFX and CFPM groups (p=0.64). Adverse events were minimal, and all patients could continue the treatment.

CONCLUSIONS

We could not prove the non-inferiority of CPFX in comparison with CFPM for the initial treatment of FN. CFPM remains the standard treatment of choice for FN.

Combination therapy for treatment of infections with gram-negative bacteria

Combination antibiotic therapy for invasive infections with Gram-negative bacteria is employed in many health care facilities, especially for certain subgroups of patients, including those with neutropenia, those with infections caused by Pseudomonas aeruginosa, those with ventilator-associated pneumonia, and the severely ill. An argument can be made for empiric combination therapy, as we are witnessing a rise in infections caused by multidrug-resistant Gram-negative organisms. The wisdom of continued combination therapy after an organism is isolated and antimicrobial susceptibility data are known, however, is more controversial. The available evidence suggests that the greatest benefit of combination antibiotic therapy stems from the increased likelihood of choosing an effective agent during empiric therapy, rather than exploitation of in vitro synergy or the prevention of resistance during definitive treatment. In this review, we summarize the available data comparing monotherapy versus combination antimicrobial therapy for the treatment of infections with Gram-negative bacteria.

Infections in Leukemia and Hematopoietic Stem Cell Transplantation

Infections are one of the most common complications in patients diagnosed with leukemia and serve as a major obstacle to treatment. Through the early 1970s, infections were the most common cause of death in patients diagnosed with acute leukemia, but improvement in treatment and supportive care over the past few decades, coupled with expanded prophylaxis and prevention regimens, have led to reduction in both the frequency and severity of infections. Regardless, due in part to an aging cancer population and the diversity of cancer treatments and procedures, infectious diseases remain a major cause of morbidity and mortality in patients with leukemia.

Is double coverage of gram-negative organisms necessary?

PURPOSE

The appropriateness of combination therapy for infections caused by gram-negative organisms is examined.

SUMMARY

Mortality from Pseudomonas aeruginosa infection is particularly high; therefore, empirical regimens are often selected to ensure coverage for this organism. The initial use of combination antimicrobial therapy for gram-negative infections is usually justified by one of three reasons: the potential for synergistic activity between two classes of antimicrobial agents, the broad empirical coverage provided by two antimicrobial agents with differing spectra of activity and resistance patterns, or the prevention of resistance development during antimicrobial therapy. Disadvantages of using combination therapy are increased drug toxicity, increased costs, and increased risk of superinfection with more-resistant bacteria or fungi. There are no clinical data that suggest that the combination of a β-lactam plus a fluoroquinolone results in improved patient outcomes compared with a β-lactam alone or a β-lactam plus an aminoglycoside. Results from studies that evaluate combination therapy versus monotherapy for gram-negative bacilli conflict with the common practice of use of double coverage. Strong evidence to support the administration of antimicrobials for double coverage of gram-negative organisms is lacking. Antimicrobial overuse may lead to antibiotic resistance, unnecessary adverse effects, and increased costs.

CONCLUSION

The available clinical evidence does not support the routine use of combination antimicrobial therapy for treatment of gram-negative infections. Patients with shock or neutropenia may benefit from combination therapy that includes an aminoglycoside.

Aminoglycoside-free interventional antibiotic management in patients undergoing haemopoietic stem cell transplantation

The position of aminoglycosides within interventional antibiosis in the early phase after stem cell transplantation has not been fully clarified so far although their use can induce serious renal impairment. To investigate this question early-infection data from 152 patients undergoing 195 allogeneic and autologous stem cell transplantations were investigated. Prophylaxis and treatment of infections followed international standards; however, aminoglycosides were omitted to avoid additional risks such as ototoxicity and nephrotoxicity and increased selection of resistant pathogens. Costs were another aspect.

The overall-incidence of infections was 78% (152/195) and 67 patients showed more than one episode of infection. Fever of unknown origin and bacteriaemia/septicaemia dominated the spectrum of infections. The overall-response to interventional regimen consisting of β-lactam or carbapenem plus glycopeptides was 48%. Aminoglycosides were given in three patients in the late course of disease. Overall mortality was 15/195 (7.7%) and clearly related to infection in nine cases mostly due to mould infection. A comparison with previous published literature showed no hint for inferiority of ‘aminoglycoside-free’ antibiotic management in stem cell transplant patients. In conclusion, the present analysis supports the policy to omit aminoglycosides in the therapy of early infections in patients undergoing stem cell transplantation to avoid additional toxicity.

Beta-lactam and fluoroquinolone combination antibiotic therapy for bacteremia caused by gram-negative bacilli

The role of combination antibiotic therapy with a beta-lactam and a fluoroquinolone for bacteremia caused by gram-negative bacilli, to our knowledge, has not been previously described. Much of the previous study of combination therapy has included beta-lactams and aminoglycosides. We conducted a large retrospective cohort study to evaluate 28-day all-cause mortality in patients with monomicrobial bacteremia due to aerobic gram-negative bacilli who received either a combination of beta-lactams and fluoroquinolones or beta-lactam monotherapy. We enrolled adult patients admitted to Mayo Clinic hospitals from 1 January 2001 to 31 October 2006 in the study. After stratification of patients by Pitt bacteremia scores, we used Cox regression models to estimate the hazard ratios (HR) for 28-day all-cause mortality after adjusting for the propensity to receive combination therapy. We identified 398 and 304 unique patients with bacteremia caused by gram-negative bacilli who received single and combination antibiotic therapy, respectively. In less severely ill patients with Pitt bacteremia scores of <4, combination therapy was associated with lower 28-day mortality than single therapy (4.2% [9 of 214] versus 8.8% [28 of 319]; adjusted HR, 0.44; 95% confidence interval [CI], 0.20 to 0.98; P = 0.044). In critically ill patients with Pitt bacteremia scores of >or=4, there was no difference in 28-day mortality between combination and single therapy (25.6% [23 of 90] versus 27.8% [22 of 79]; adjusted HR, 0.87; 95% CI, 0.47 to 1.62; P = 0.660). These findings were consistent for 14-day all-cause mortality. In this large cohort, we found for the first time that combination therapy with beta-lactams and fluoroquinolones was associated with a reduction in 28-day all-cause mortality among less severely ill patients with bacteremia caused by gram-negative bacilli.

Respiratory fluoroquinolones for the treatment of community-acquired pneumonia: a meta-analysis of randomized controlled trials

BACKGROUND

We investigated whether the use of respiratory fluoroquinolones was associated with better clinical outcomes compared with the use of macrolides and beta- lactams among adults with pneumonia.

METHODS

We searched PubMed, Current Contents, Scopus, EMBASE, ClinicalTrials.gov and Cochrane with no language restrictions. Two reviewers independently extracted data from published trials that compared fluoroquinolones (levofloxacin, moxifloxacin, gemifloxacin) with macrolides or beta-lactams or both. A meta-analysis was performed with the clinical outcomes of mortality, treatment success and adverse outcomes.

RESULTS

We included 23 trials in our meta-analysis. There was no difference in mortality among patients who received fluoroquinolones or the comparator antibiotics (OR 0.85, 95% CI 0.65-1.12). Pneumonia resolved in more patients who received fluoroquinolones compared with the comparator antibiotics for the included outcomes in the intention-to-treat population (OR 1.17, 95% CI 1.00-1.36), clinically evaluable population (OR 1.26, 95% CI 1.06-1.50) and the microbiologically assessed population (OR 1.67, 95% CI 1.28-2.20). Fluoroquinolones were more effective than a combination of beta-lactam and macrolide (OR 1.39, 95% CI 1.02-1.90). They were also more effective for patients with severe pneumonia (OR 1.84, 95% CI 1.02-3.29), those who required admission to hospital (OR = 1.30, 95% CI 1.04-1.61) and those who required intravenous therapy (OR = 1.44, 15% CI 1.13-1.85). Fluoroquinolones were more effective than beta-lactam and macrolide in open-label trials (OR = 1.35, 95% CI 1.08-1.69) but not in blinded randomized controlled trials (OR = 1.13, 95% CI 0.85-1.50).

INTERPRETATION

Fluoroquinolones were associated with higher success of treatment for severe forms of pneumonia; however, a benefit in mortality was not evident. A randomized controlled trial that includes patients with severe pneumonia with or without bacteremia is needed.

Aminoglycoside drugs in clinical practice: an evidence-based approach

Resistant bacteria have renewed our interest in the aminoglycoside drugs. Evidence on the efficiency of aminoglycosides in their different clinical uses is available from numerous randomized controlled trials and has been accrued and examined in recent systematic reviews and meta-analyses. Their results show that aminoglycosides should not be added to broad-spectrum beta-lactams to achieve synergism in treating Gram-negative infections as combination does not improve efficacy and adds side effects. The evidence from randomized trials in humans does not support the use of aminoglycosides in staphylococcal or streptococcal endocarditis, and is lacking for endocarditis caused by enterococci. Aminoglycosides are efficacious and safe as single drugs for the treatment of pyelonephritis and sepsis of a urinary source, but their efficacy might be lower than that of beta-lactams in Gram-negative infections of other sources. In patients with no risk factors, aminoglycosides are as safe as beta-lactams regarding side effects. They probably induce less resistance. Pragmatic large trials are needed to answer open clinical questions on the use of aminoglycosides.

Decreasing the incidence and impact of infections in neutropenic patients: evidence from meta-analyses of randomized controlled trials

BACKGROUND

[corrected] Neutropenia is a common complication of intensive chemotherapy in patients with solid organ or hematologic malignancies that is associated with a high risk for life-threatening infections. Many interventions have been employed in order to limit the incidence of these infections or to treat them when the prophylactic measures fail.

SCOPE

The commonest characteristic of the randomized controlled trials (RCTs) conducted on this issue was the small sample size. In addition, if RCTs studying the prophylactic interventions were excluded, the aim of most of the rest of relevant RCTs was to prove the equal effectiveness of the tested interventions in terms of treatment success. We searched PubMed and Cochrane database to identify meta-analyses of RCTs in the field of febrile neutropenia.

RESULTS

The most prominent findings of these meta-analyses were the promising effect, although based on open label RCTs, of antimicrobial prophylaxis with fluoroquinolones on the mortality of all neutropenic patients and the beneficial effect of antifungal prophylaxis on mortality of neutropenic patients with allogeneic hematopoetic stem cell transplantation. Another noteworthy finding was the higher mortality associated with empiric cefepime treatment when compared with other beta-lactams. In other cases, the findings of the published meta-analyses either confirmed or consolidated the results of individual RCTs.

CONCLUSION

Meta-analyses are very useful for obtaining a better overview and to provide some general qualitative and quantitative conclusions, but are not always a substitute for appropriately powered, well-designed RCTs. In addition, the reported findings should be interpreted with caution taking into account the limitations of various methodological aspects of meta-analysis in general, as well as the limitations of the individual meta-analyses in this field.