Levofloxacin in the empirical treatment of patients with suspected bacteraemia/sepsis: comparison with imipenem/cilastatin in an open, randomized trial

Oral Is the New IV. Challenging Decades of Blood and Bone Infection Dogma: A Systematic Review

BACKGROUND

We sought to determine if controlled, prospective clinical data validate the long-standing belief that intravenous (IV) antibiotic therapy is required for the full duration of treatment for 3 invasive bacterial infections: osteomyelitis, bacteremia, and infective endocarditis.

METHODS

We performed a systematic review of published, prospective, controlled trials that compared IV-only to oral stepdown regimens in the treatment of these diseases. Using the PubMed database, we identified 7 relevant randomized controlled trials (RCTs) of osteomyelitis, 9 of bacteremia, 1 including both osteomyelitis and bacteremia, and 3 of endocarditis, as well as one quasi-experimental endocarditis study. Study results were synthesized via forest plots and funnel charts (for risk of study bias), using RevMan 5.4.1 and Meta-Essentials freeware, respectively.

RESULTS

The 21 studies demonstrated either no difference in clinical efficacy, or superiority of oral versus IV-only antimicrobial therapy, including for mortality; in no study was IV-only treatment superior in efficacy. The frequency of catheter-related adverse events and duration of inpatient hospitalization were both greater in IV-only groups.

DISCUSSION

Numerous prospective, controlled investigations demonstrate that oral antibiotics are at least as effective, safer, and lead to shorter hospitalizations than IV-only therapy; no contrary data were identified. Treatment guidelines should be modified to indicate that oral therapy is appropriate for reasonably selected patients with osteomyelitis, bacteremia, and endocarditis.

The effects of adding quinolones to beta-lactam antibiotics for sepsis

BACKGROUND

Sepsis is common, deadly, and a major challenge to treat. Quinolones added to beta-lactam antibiotics are currently recommended as a second-line empiric regimen in sepsis, but the evidence regarding their benefits and harms is unclear.

OBJECTIVE

To assess the benefits and harms of adding quinolones to standard care for sepsis.

DATA SOURCES

We conducted a systematic review of randomized clinical trials with meta-analysis and Trial Sequential Analysis. We searched CENTRAL, MEDLINE, Embase, LILACS, SCI-Expanded, and BIOSIS.

STUDY SELECTION

Randomized clinical trials assessing the effects of adding any quinolone to standard care for children and adults with sepsis.

DATA EXTRACTION AND SYNTHESIS

Two independent reviewers screened studies and extracted data. The certainty of the evidence was assessed by GRADE.

RESULTS

We included three trials randomizing 995 adults. All trials were at overall "high risk of bias." All trials compared a quinolone (moxifloxacin, levofloxacin, or ciprofloxacin) and a beta-lactam antibiotic versus the same beta-lactam antibiotic. We found no evidence of an effect of adding quinolones to beta-lactam antibiotics when assessing all-cause mortality (RR 1.07, 95% CI 0.86 to 1.33; 2 trials; 915 participants; very low certainty of evidence) and serious adverse events (RR 1.00, 95% CI 0.67 to 1.50; 977 participants; two trials; very low certainty of evidence). No trials reported on quality of life.

CONCLUSIONS

The effects of adding quinolones to beta-lactam antibiotics for the treatment of sepsis were unclear for all outcomes. Additional trial data are warranted to support the recommendation of empirical use of quinolones for sepsis.

Rapid and sensitive determination of levofloxacin in microsamples of human plasma by high-performance liquid chromatography and its application in a pharmacokinetic study

A rapid, sensitive and simple high-performance liquid chromatographic assay with ultraviolet detection was developed for the quantification of levofloxacin in microsamples (100 μL) of human plasma. The extraction procedure included a protein precipitation technique and a short chromatographic running time (4.5 min). Analyses were carried out on a Symmetry C18 column using a mixture of acetonitrile and 0.01 m potassium dihydrogen aqueous solution (pH 3.4; 14:86 v/v) as mobile phase. The method provided specificity and was linear (r ≥ 0.9992) over the concentration range 0.1-12 µg/mL. The average absolute recovery was 93.59%. The intra- and inter-day coefficients of variation were <6%. Additionally, levofloxacin was stable in all evaluations. The usefulness of this method was demonstrated in a pharmacokinetic study of levofloxacin in healthy adult volunteers. The present method offers two main advantages: (a) the use of microsamples reduces the total volume of blood to be collected from patients; and (b) it provides a good cost-effectiveness ratio. It is concluded that the method is rapid, simple, sensitive, economical and suitable for the determination of levofloxacin in human plasma using a small volume of sample.

Levofloxacin: update and perspectives on one of the original ‘respiratory quinolones’

The fluoroquinolone class of antimicrobials has enjoyed enormous clinical and marketing success over the past 20 years. These drugs have proven to be extremely useful in a broad range of clinical indications including both common community-acquired as well as nosocomial bacterial infections. Levofloxacin (Levaquin, Tavanic), like ciprofloxacin (Cipro), has established an enviable record of safe and efficacious use, and in many ways has become the agent against which all of the newer fluoroquinolones are judged. New clinical indications in complicated skin and skin structure infections, nosocomial pneumonia and chronic bacterial prostatitis continue to expand the important role of this already versatile drug. In addition, the use of 'short-course, high-dose' therapies are being studied in indications, such as community-acquired pneumonia, in an effort to optimize the efficacy and convenience of the drug while minimizing the future development of resistance. As the use of levofloxacin continues to expand, future challenges will include the threat of increasing antimicrobial resistance and the availability of newer alternative agents, both newer fluoroquinolones as well as agents of other antibiotic classes.

Elderly patients with community-acquired pneumonia: optimal treatment strategies

Community-acquired pneumonia (CAP) is a common infectious disease that still causes substantial morbidity and mortality. Elderly people are frequently affected, and several issues related to care of this condition in the elderly have to be considered. This article reviews current recommendations of guidelines with a special focus on aspects of the care of elderly patients with CAP. The most common pathogen in CAP is still Streptococcus pneumoniae, followed by other pathogens such as Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydophila pneumoniae and Legionella species. Antimicrobial resistance is an increasing problem, especially with regard to macrolide-resistant S. pneumoniae and fluoroquinolone-resistant strains. With regard to β-lactam antibacterials, resistance by H. influenzae and Moraxella catarrhalis is important, as is the emergence of multidrug-resistant Staphylococcus aureus. The main management decisions should be guided by the severity of disease, which can be assessed by validated clinical risk scores such as CURB-65, a tool for measuring the severity of pneumonia based on assessment of confusion, serum urea, respiratory rate and blood pressure in patients aged ≥65 years. For the treatment of low-risk pneumonia, an aminopenicillin such as amoxicillin with or without a β-lactamase inhibitor is frequently recommended. Monotherapy with macrolides is also possible, although macrolide resistance is of concern. When predisposing factors for special pathogens are present, a β-lactam antibacterial combined with a β-lactamase inhibitor, or the combination of a β-lactam antibacterial, a β-lactamase inhibitor and a macrolide, may be warranted. If possible, patients who have undergone previous antibacterial therapy should receive drug classes not previously used. For hospitalized patients with non-severe pneumonia, a common recommendation is empirical antibacterial therapy with an aminopenicillin in combination with a β-lactamase inhibitor, or with fluoroquinolone monotherapy. With proven Legionella pneumonia, a combination of β-lactams with a fluoroquinolone or a macrolide is beneficial. In severe pneumonia, ureidopenicillins with β-lactamase inhibitors, broad-spectrum cephalosporins, macrolides and fluoroquinolones are used. A combination of a broad-spectrum β-lactam antibacterial (e.g. cefotaxime or ceftriaxone), piperacillin/tazobactam and a macrolide is mostly recommended. In patients with a predisposition for Pseudomonas aeruginosa, a combination of piperacillin/tazobactam, cefepime, imipenem or meropenem and levofloxacin or ciprofloxacin is frequently used. Treatment duration of more than 7 days is not generally recommended, except for proven infections with P. aeruginosa, for which 15 days of treatment appears to be appropriate. Further care issues in all hospitalized patients are timely administration of antibacterials, oxygen supply in case of hypoxaemia, and fluid management and dose adjustments according to kidney function. The management of elderly patients with CAP is a challenge. Shifts in antimicrobial resistance and the availability of new antibacterials will change future clinical practice. Studies investigating new methods to detect pathogens, determine the optimal antimicrobial regimen and clarify the duration of treatment may assist in further optimizing the management of elderly patients with CAP.

Broad-spectrum antimicrobials and the treatment of serious bacterial infections: getting it right up front

The treatment of serious bacterial infections is complicated by the fact that time to initiation of effective antimicrobial therapy is a strong predictor of mortality. Therefore, therapy must be initiated before the causative pathogen is identified. However, inappropriate or inadequate initial empirical therapy is associated with increased mortality, morbidity, and length of hospital stay. Initial empirical therapy with broad-spectrum antimicrobials attempts to address this dilemma by "getting it right up front." The goal is to provide treatment active against the most likely pathogens until culture/susceptibility test results are obtained. After the causative pathogen is identified, streamlining to more-precise therapy of the shortest acceptable duration is implemented. In this way, the risks of death, morbid complications, increased duration of hospital stay (as a result of ineffective initial treatment), and emergence of resistance (due to extended treatment with broad-spectrum agents) are lowered. Improved clinical and economic outcomes after such an approach have been demonstrated.

Efficacy of the combination of levofloxacin plus ceftazidime in the treatment of hospital-acquired pneumonia in the Intensive Care Unit

To investigate the efficacy and tolerability of treatment with a combination of levofloxacin and ceftazidime in Gram-negative hospital-acquired pneumonia (HAP) in the Intensive Care Unit (ICU), we performed a prospective, open-label, non-comparative, 1-year study in an Italian ICU. Patients received levofloxacin 500 mg twice a day intravenously plus ceftazidime 2 g three times a day intravenously for 7-14 days. Primary efficacy variables were clinical and microbiological responses at test-of-cure visit. Twenty-one patients were enrolled. Pseudomonas aeruginosa and Klebsiella pneumoniae were the most frequently identified pathogens. Clinical success was achieved in 17/21 clinically evaluable patients (81%) and in 12/15 microbiologically evaluable patients (80%). Regarding only the group with ventilator-associated pneumonia, cure was achieved in 10/14 clinically evaluable patients (71%) and in 11/14 microbiologically evaluable patients (79%). Therapy was well tolerated. We conclude that this combination regimen is safe and clinically and microbiologically efficacious in the treatment of Gram-negative HAP.

Levofloxacin in the treatment of ventilator-associated pneumonia

The use of levofloxacin in critically ill patients has progressively increased since commercial marketing of the drug in 1999, despite the fact that few studies have been designed to assess the use of levofloxacin in this population. Pharmacological characteristics, broad spectrum of activity, and tolerability account for the high interest in the drug for the treatment of different infectious diseases, including ventilator-associated pneumonia (VAP), and the recommendation of levofloxacin in guidelines developed by a number of scientific societies. According to pharmacokinetic-pharmacodynamic data, it seems reasonable to assume that an increase in activity follows from a larger dose, so that 500 mg/12 h is adequate in patients with VAP. In critically ill patients with VAP, levofloxacin monotherapy is indicated for empirical treatment of patients with early onset pneumonia without risk factors for multiresistant pathogens, and in combination therapy for late onset VAP or for patients at risk for multiresistant pathogens. The use of levofloxacin in combination therapy is supported by multiple reasons, including: increased empirical coverage in infections with suspected intracellular pathogens; substitution for more toxic antimicrobial agents (e.g., aminoglycosides) in patients with renal dysfunction and in those at risk for renal insufficiency; and severity of systemic response to infection (septic shock) that justifies multiple treatment with better tolerated antibiotics. The availability of the oral formulation allows sequential therapy, switching from the intravenous route to the oral route. Levofloxacin is well tolerated by critically ill patients, with few adverse events of mild to moderate severity.

Highlights on the appropriate use of fluoroquinolones in respiratory tract infections

The impact of respiratory infections on public health is increasing, and lower respiratory tract infections are a major cause of morbidity and mortality. Moreover, most antibiotic prescriptions are related to respiratory infections and this is probably one of the main determinants of the increasing rate of bacterial resistance in both community and hospital settings. This has been the catalyst for the development of new drugs, such as the new fluoroquinolones. The new fluoroquinolones have an excellent spectrum providing cover for the most important respiratory pathogens, including atypical and "typical" pathogens. The pharmacokinetic and dynamic properties of the new fluoroquinolones have a significant impact on their clinical and bacteriological efficacy. They cause a concentration-dependent killing with a sustained post-antibiotic effect. Fluoroquinolones combine exceptional efficacy with cost-effectiveness. Not surprisingly, different guidelines have inserted these agents among the drugs of choice in the empirical therapy of LRTIs. This review discusses the most recent data on the bacteriological and clinical activity of the new fluoroquinolones and critically analyses the risks of a potential overuse of this valuable new class of drugs.

Manejo del paciente con neutropenia de bajo riesgo y fiebre

For years the classical approach to febrile episodes in patients with chemotherapy-induced neutropenia consisted of hospital admission and intravenous administration of broad-spectrum antibiotics. However, since the end of the 1980s, it has been known that not all episodes of neutropenia carry the same risk of developing complications. These low risk febrile patients with neutropenia, that is, those without a clear focus of infection, without criteria for severe sepsis, and with an expected duration of neutropenia of less than 7-10 days, could benefit from outpatient oral antibiotic therapy or, failing this, from intravenous administration through a perfusion pump in the home. The present study analyzes the current situation of the new treatment modalities that aim to improve patients' quality of life and to optimize healthcare resources and costs.

Relevance of soft-tissue penetration by levofloxacin for target site bacterial killing in patients with sepsis

Antimicrobial therapy of soft tissue infections in patients with sepsis sometimes lacks efficiency, despite the documented susceptibility of the causative pathogen to the administered antibiotic. In this context, impaired equilibration between the antibiotic concentrations in plasma and those in tissues in critically ill patients has been discussed. To characterize the impact of tissue penetration of anti-infective agents on antimicrobial killing, we used microdialysis to measure the concentration-versus-time profiles of levofloxacin in the interstitial space fluid of skeletal muscle in patients with sepsis. Subsequently, we applied an established dynamic in vivo pharmacokinetic-in vitro pharmacodynamic approach to simulate bacterial killing at the site of infection. The population mean areas under the concentration-time curves (AUCs) for levofloxacin showed that levofloxacin excellently penetrates soft tissues, as indicated by the ratio of the AUC from time zero to 8 h (AUC(0-8)) for muscle tissue (AUC(0-8 muscle)) to the AUC(0-8) for free drug in plasma (AUC(0-8 plasma free)) (AUC(0-8 muscle)/AUC(0-8 plasma free) ratio) of 0.85. The individual values of tissue penetration and maximum concentration (C(max)) in muscle tissue were highly variable. No difference in bacterial killing of a select Staphylococcus aureus strain for which the MIC was 0.5 microg/ml was found between individuals after exposure to dynamically changing concentrations of levofloxacin in plasma and tissue in vitro. In contrast, the decrease in the bacterial counts of Pseudomonas aeruginosa (MIC = 2 microg/ml) varied extensively when the bacteria were exposed to levofloxacin at the concentrations determined from the individual concentration-versus-time profiles obtained in skeletal muscle. The extent of bacterial killing could be predicted by calculating individual C(max)/MIC and AUC(0-8 muscle)/AUC(0-8 plasma free) ratios (R = 0.96 and 0.93, respectively). We have therefore shown in the present study that individual differences in the tissue penetration of levofloxacin may markedly affect target site killing of bacteria for which MICs are close to 2 microg/ml.

Current and future perspectives for levofloxacin in severe Pseudomonas aeruginosa infections

The question of whether levofloxacin includes Pseudomonas aeruginosa in its spectrum of clinical activity is discussed by reviewing the major findings on this issue, mainly those published in Italy. The in vitro activity of levofloxacin against P. aeruginosa is now documented on thousands of strains worldwide. The pharmacodynamic properties of levofloxacin allow for the treatment of pseudomonal infections. The levofloxacin clinical results extrapolated from published studies document the efficacy of levofloxacin in the treatment of infections sustained by P. aeruginosa.

Therapeutic potential of the new quinolones in the treatment of lower respiratory tract infections

The impact of respiratory infections on public health is increasing and lower respiratory tract infections are a major cause of morbidity and mortality. We are also facing a worldwide burst of antibiotic bacterial resistance. The new fluoroquinolones have an excellent spectrum covering the most important respiratory pathogens, including atypical and 'typical' pathogens. Pharmacokinetic and dynamic properties of the new fluoroquinolones have a significant impact on their clinical and bacteriological efficacy. They cause a concentration-dependent killing with a sustained postantibiotic effect. Fluoroquinolones combine exceptional efficacy with cost-effectiveness. Not surprisingly, different guidelines have inserted these agents among the drugs of choice in the empirical therapy of community-acquired pneumonia. This review discusses the more recent data on bacteriological and clinical activity and critically analyses the risks of a potential overuse of this valuable new class of drugs.

Ambulant erworbene und nosokomiale Pneumonie

Mortality of pneumonia is low in the outside setting (1%) but rises up to 20% in hospital admitted patients. Early diagnosis and standardized therapy improve patient's prognosis. For community acquired pneumonia age, comorbidity and the setting of therapy (outside department, normal ward or intensive care unit) are the most important variables to choose an adequate antibiotic treatment. For nosocomial pneumonia risk stratification is according to severity of illness, length of hospital stay and antibiotic pretreatment. In the outpatient setting a 7-day monotherapy is mostly successful. In severe illness the combination of a betalactam antibiotic with a new fluorchinolon seems to be superior to an aminoglycosid therapy. Antibiotic resistance due to mistakes in antibiotic therapy is an increasing problem in the intensive care unit. Therefore, pneumonia preventive measures like influenza and pneumococcal vaccination become more important. Standardized hygienical procedures help to reduce nosocomial, mainly ventilator associated pneumonia.

Pharmacokinetics of intravenous and oral levofloxacin in critically ill adults in a medical intensive care unit

STUDY OBJECTIVE

To characterize the pharmacokinetic disposition of intravenous and oral levofloxacin in critically ill adults.

DESIGN

Prospective, open-label study.

SETTING

University teaching hospital.

PATIENTS

Thirty critically ill patients in a medical intensive care unit (ICU).

INTERVENTIONS

All patients received levofloxacin as part of their routine medical care. Pharmacokinetic evaluations were performed in 28 patients receiving intravenous levofloxacin. Ten of these patients subsequently were switched to oral levofloxacin and underwent a second pharmacokinetic evaluation during oral therapy.

MEASUREMENTS AND MAIN RESULTS

Mean +/- SD levofloxacin half-life, clearance at steady state, and volume of distribution in all 28 patients were 8.0 +/- 1.7 hours, 134 +/- 35 ml/minute, and 1.2 +/- 0.3 L/kg, respectively Maximum and minimum serum concentrations (Cmax and Cmin) and area under the serum concentration-time curve from 0-24 hours (AUC(0-24)) in patients receiving levofloxacin 500 mg intravenously were 7.5 +/- 0.8 mg/L, 1.0 +/- 0.5 mg/L, and 66.1 +/- 15.7 mg x hour/L, respectively Observed Cmax, Cmin, and time at which maximum concentration was achieved after oral doses of levofloxacin 500 mg were 5.5 +/- 1.1 mg/L, 0.8 +/- 0.4 mg/L, and 1.3 +/- 0.4 hours, respectively. These values were significantly different (p < 0.05) from those observed after intravenous dosing in the same patients; other pharmacokinetic parameters were similar. Statistically significant increases (p < 0.05) in Cmax, Cmin, half-life, and AUC(0-24) were found in critically ill patients administered multiple doses of intravenous levofloxacin compared with historical data from healthy volunteers.

CONCLUSIONS

The dosage regimen of intravenous levofloxacin 500 mg once/day appears adequate for most pathogens found in critically ill patients with normal renal function. Less susceptible pathogens may require an increased daily dose for more optimal therapy. Orally administered levofloxacin appears to be well absorbed in selected ICU patients and has pharmacokinetics similar to those of intravenously administered levofloxacin.

A Risk-Benefit Assessment of Levofloxacin in Respiratory, Skin and Skin Structure, and Urinary Tract Infections

As a class, the quinolone antibacterials can no longer be assumed to be both effective and relatively free of significant adverse effects. Recent safety issues with newer generation fluoroquinolones, and concerns regarding drug-use associated bacterial resistance have made all drugs in this class subject to intense scrutiny and further study. Levofloxacin is a second generation fluoroquinolone with a post marketing history of well tolerated and successful use in a variety of clinical situations. Quinolones as a class cause a variety of adverse effects, including phototoxicity, seizures and other CNS disturbances, tendonitis and arthropathies, gastrointestinal effects, nephrotoxicity, prolonged QTc interval and torsade de pointes, hypo- or hyperglycaemia, and hypersensitivity reactions. Levofloxacin has been involved in only a few case reports of adverse events, which include QTc prolongation, seizures, glucose disturbances, and tendonitis. Levofloxacin has been shown to be effective at dosages of 250mg to 500mg once-daily in clinical trials in the management of acute maxillary sinusitis, acute bacterial exacerbations of chronic bronchitis, community-acquired pneumonia, skin and skin structure infections, and urinary tract infections. There are data suggesting that levofloxacin may promote fluoroquinolone resistance among the Streptococcus pneumoniae, and that clinical failures may result from this therapy. Other data suggest that fluoroquinolones with lower potency against Pseudomonas aeruginosa than ciprofloxacin, such as levofloxacin, may drive class-wide resistance to this pathogen. Levofloxacin is an effective drug in many clinical situations, but its cost is significantly higher than amoxicillin, erythromycin, or first and second generation cefalosporins. Because of the propensity to select for fluoroquinolone resistance in the pneumococcus and potentially other pathogens, levofloxacin should be an alternative agent rather than a drug-of-choice in routine community-acquired respiratory tract, urinary tract, and skin or skin structure infections. In areas with increasing pneumococcal beta-lactam resistance, levofloxacin may be a reasonable empiric therapy in community-acquired respiratory tract infections. Similarly, in patients with risk factors for infectious complications or poor outcome, levofloxacin may be an excellent empiric choice in severe community-acquired respiratory tract infections, urinary tract infections, complicated skin or skin structure infections, and nosocomial respiratory and urinary tract infections. Better clinical data are needed to identify the true place in therapy of the newer fluoroquinolones in common community-acquired and nosocomial infections. Until then, these agents, including levofloxacin, might best be reserved for complicated infections, infection recurrence, and infections caused by beta-lactam or macrolide-resistant pathogens.