Adverse Effects of Intravenous Vancomycin-Based Prophylaxis during Therapy for Pediatric Acute Myeloid Leukemia

Children and adolescents with acute myeloid leukemia (AML) are at risk of life-threatening bacterial infections, especially with viridans group streptococci. Primary antibacterial prophylaxis with vancomycin-based regimens reduces this risk but might increase the risks of renal or liver toxicity or Clostridium difficile infection (CDI). A retrospective review of data for patients treated for newly diagnosed AML at St. Jude Children's Research Hospital between 2002 and 2008 was conducted. Nephrotoxicity was classified according to pediatric risk, injury, failure, loss, and end-stage renal disease (pRIFLE) criteria and hepatotoxicity according to Common Terminology Criteria for Adverse Events (CTCAE) criteria. The risks of nephrotoxicity, hepatotoxicity, and CDI were compared between patients receiving vancomycin-based prophylaxis, no intravenous prophylaxis, or other prophylaxis. Generalized linear mixed models were used to address potential confounding. A total of 392 chemotherapy courses (108 with no intravenous prophylaxis, 218 with vancomycin-based prophylaxis, and 66 with other prophylaxis) for 111 patients were included. Development of pRIFLE risk, injury, and failure occurred in 190, 44, and 2 courses, respectively. Increases of at least one, two, and three grades for hepatotoxicity occurred in 189, 52, and 19 courses, respectively. After adjustment for confounders, vancomycin-based prophylaxis was not associated with nephrotoxicity or hepatotoxicity and reduced the risk of CDI, compared to no intravenous prophylaxis (0.9% versus 6.5%; P = 0.007) or other prophylactic regimens (0.9% versus 3.0%; P = 0.23). Despite concerns about vancomycin toxicity, vancomycin-based prophylaxis in pediatric patients with AML did not increase the risk of nephrotoxicity or hepatotoxicity and reduced the risk of CDI. Caution is advised to avoid contributing to antibiotic resistance.

Acute renal failure due to vancomycin toxicity in the setting of unmonitored vancomycin infusion

Vancomycin-induced nephrotoxicity is a commonly feared and largely preventable adverse effect of vancomycin therapy. We present the case of a 56-year-old woman who developed acute renal failure requiring hemodialysis as a result of unmonitored vancomycin infusions for the treatment of osteomyelitis.

A population pharmacokinetic model for individualised dosage regimens of vancomycin in Chinese neonates and young infants

Population pharmacokinetic (PPK) modelling is an easy and impartment method for estimating drug concentration for use inindividualized therapy, especially for young patients and to help protect drug-induced diseases. The purpose of this study was to develop a PPK model for effective dosing of vancomycin in Chinese neonates and young infants. The PPK modelling tool Phoenix^® NLME^™ was use to assess demographic and routine clinical pharmacokinetic (PK) data retrospectively collected for patients admitted to Children's Hospital of Chongqing Medical University between 2011 and 2016. Data of patients admitted to the hospital between January and June of 2017 were used in validation study, and the final model was also preliminary validated in 2 cases in another hospital. A total of 421 serum samples from 316 patients were included in the initial PPK analysis. A two-compartment PPK model was developed, and exponential-error model was used to describe inter-individual variability of clearance. Residual variability was described by an additive model. The final PPK model was demonstrated as valid by internal and external model evaluation. Of note, the clearance and volume of vancomycin in Chinese neonates and young infants may be greater than in Caucasians. Herein, we describe the establishment of an accurate PPK model of vancomycin for Chinese neonates and young infants, which may be useful as a dosing algorithm for this particular paediatric population.

Pharmacokinetic/pharmacodynamic parameters for treatment optimization of infection due to antibiotic resistant bacteria: a summary for practical purposes in children and adults

In the last years, there has been a tremendous increase in the incidence of bacterial infections due to resistant strains, especially multi-drug resistant Gram-negative bacilli. In Europe, a north to south and a west to east gradient was noticed, with more than one third of the K. pneumonia isolates being resistant to carbapenems in few countries. New antibiotics are lacking and, as a consequence, pharmacokinetic/pharmacodynamic parameters, normalized to pathogen minimal inhibitory concentration, are used with increased frequency to treat infections due to difficult-to-treat pathogens. These parameters are available at least for the adult population, but sparse in many different publications. This review wants to provide a comprehensive and 'easy to read' text for everyday practice, briefly summarizing the presently available knowledge on pharmacokinetic/pharmacodynamic parameters (normalized for minimal inhibitory concentration values) of different class drugs, that can be applied for an effective antibacterial treatment infections due to antibiotic-resistant pathogens.

Design and Implementation of a Novel Web-Based E-Learning Tool for Education of Health Professionals on the Antibiotic Vancomycin

Background

Traditional approaches to health professional education are being challenged by increased clinical demands and decreased available time. Web-based e-learning tools offer a convenient and effective method of delivering education, particularly across multiple health care facilities. The effectiveness of this model for health professional education needs to be explored in context.

Objectives

The study aimed to (1) determine health professionals’ experience and knowledge of clinical use of vancomycin, an antibiotic used for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA) and (2) describe the design and implementation of a Web-based e-learning tool created to improve knowledge in this area.

Methods

We conducted a study on the design and implementation of a video-enhanced, Web-based e-learning tool between April 2014 and January 2016. A Web-based survey was developed to determine prior experience and knowledge of vancomycin use among nurses, doctors, and pharmacists. The Vancomycin Interactive (VI) involved a series of video clips interspersed with question and answer scenarios, where a correct response allowed for progression. Dramatic tension and humor were used as tools to engage users. Health professionals’ knowledge of clinical vancomycin use was obtained from website data; qualitative participant feedback was also collected.

Results

From the 577 knowledge survey responses, pharmacists (n=70) answered the greatest number of questions correctly (median score 4/5), followed by doctors (n=271; 3/5) and nurses (n=236; 2/5; P<.001). Survey questions on target trough concentration (75.0%, 433/577) and rate of administration (64.9%, 375/577) were answered most correctly, followed by timing of first level (49%, 283/577), maintenance dose (41.9%, 242/577), and loading dose (38.0%, 219/577). Self-reported “very” and “reasonably” experienced health professionals were also more likely to achieve correct responses. The VI was completed by 163 participants during the study period. The rate of correctly answered VI questions on first attempt was 65% for nurses (n=63), 68% for doctors (n=86), and 82% for pharmacists (n=14; P<.001), reflecting a similar pattern to the knowledge survey. Knowledge gaps were identified for loading dose (39.2% correct on first attempt; 64/163), timing of first trough level (50.3%, 82/163), and subsequent trough levels (47.9%, 78/163). Of the 163 participants, we received qualitative user feedback from 51 participants following completion of the VI. Feedback was predominantly positive with themes of “entertaining,” “engaging,” and “fun” identified; however, there were some technical issues identified relating to accessibility from different operating systems and browsers.

Conclusions

A novel Web-based e-learning tool was successfully developed combining game design principles and humor to improve user engagement. Knowledge gaps were identified that allowed for targeting of future education strategies. The VI provides an innovative model for delivering Web-based education to busy health professionals in different locations.

The safety and efficacy of high versus low vancomycin trough levels in the treatment of patients with infections caused by methicillin-resistant Staphylococcus aureus: a meta-analysis

BACKGROUND

Recent guidelines have recommended vancomycin trough levels of 15-20 mg/L for treatment of serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA). However, high trough levels may increase risk of nephrotoxicity and mortality, and high vancomycin trough levels have not been well studied. This study was designed to combine safety and efficacy results from independent studies and to compare between high and low vancomycin trough levels in the treatment of MRSA-infected patients using meta-analysis.

METHODS

From 19 eligible studies, 9 studies were included in meta-analysis to compare clinical success between high and low vancomycin trough levels, while 10 and 11 studies met criteria for comparing trough levels and nephrotoxicity and trough levels and mortality, respectively. The PubMed/Medline, Web of Science, and Scopus databases, and hand searching were used to identify eligible studies dated up to March 2016. Of 2344 subjects with MRSA infection, 1036 were assigned to trough levels ≥15 mg/L and 1308 to trough levels <15 mg/L.

RESULTS

High vancomycin trough levels were found to be associated with risk of nephrotoxicity (odds ratio [OR] 2.14, 95 % confidence interval [CI] 1.42-3.23 and adjusted OR 3.33, 95 % CI 1.91-5.79). There was no evidence of difference between high and low vancomycin trough levels for mortality (OR; 1.09; 95 % CI 0.75-1.60) or clinical success (OR 1.07; 95 % CI 0.68-1.68).

CONCLUSION

In this study, high vancomycin trough levels were identified as an independent factor associated with risk of nephrotoxicity in MRSA-infected patients. Association between vancomycin trough levels and both adverse effects and clinical outcomes requires further study.

The impact of a pilot continuing professional development module on hospital pharmacists' preparedness to provide contemporary advice on the clinical use of vancomycin

BACKGROUND

Revised international clinical guidelines for the antibiotic vancomycin have changed the advice pharmacists need to provide to medical and nursing colleagues.

OBJECTIVES

(1) To determine the self-reported confidence of hospital pharmacists to provide contemporary advice on vancomycin and (2) to evaluate hospital pharmacists' knowledge to provide contemporary advice on vancomycin following a pilot continuing professional development (CPD) module.

METHODS

The study was a prospective two-phase design in an Australian teaching hospital. Phase one: a survey of pharmacist self-reported confidence to eight questions on providing contemporary advice on vancomycin. Responses were recorded using a Likert scales. Phase two: The provision of a pilot online CPD module on vancomycin containing knowledge-based assessment based on a clinical vignette. Likert scales recorded self-reported confidence were reported as median and interquartile range (IQR). Knowledge assessment was reported using descriptive statistics. The main outcome measure were the self-reported confidence, and knowledge of pharmacists regarding provision of contemporary advice on clinical vancomycin use.

RESULTS

Response rates for surveys; confidence n = 35 (72.9 %) and knowledge n = 31 (58.5 %). Phase one: confidence was highest regarding vancomycin dosing and monitoring with 71.4-81.6 % of respondents agreeing or strongly agreeing that they were confident in these domains. Respondents agreeing or strongly agreeing were least confident regarding intravenous administration and infusion related reactions, 57.1 and 45.7 % respectively. Respondents who provided advice on vancomycin >10 times in the prior 12 months reported significantly higher confidence in; therapeutic range 1 (IQR 1-2) versus 2 (IQR 1-3) p = 0.02; amending dosage based on therapeutic drug monitoring results 2 (IQR 1-3) versus 3 (IQR 2-3) p = <0.001, and providing general advice to prescribers on vancomycin 2 (IQR 1-3) versus 2 (IQR 2-4) p = <0.009. Knowledge questions were answered correctly post CPD by >75 % of pharmacists.

CONCLUSION

Pharmacists' self-reported confidence to managing vancomycin was variable but generally high. Knowledge scores were consistently high after pharmacists completed a pilot CPD module on vancomycin. These data provides impetus for a randomised controlled study across multiple sites to determine the extent to which pharmacist knowledge on vancomycin can be attributed to completion of an online CPD.

Staphylococcus epidermidis as a cause of bacteremia

Staphylococcus epidermidis is a biofilm-producing commensal organism found ubiquitously on human skin and mucous membranes, as well as on animals and in the environment. Biofilm formation enables this organism to evade the host immune system. Colonization of percutaneous devices or implanted medical devices allows bacteria access to the bloodstream. Isolation of this organism from blood cultures may represent either contamination during the blood collection procedure or true bacteremia. S. epidermidis bloodstream infections may be indolent compared with other bacteria. Isolation of S. epidermidis from a blood culture may present a management quandary for clinicians. Over-treatment may lead to patient harm and increases in healthcare costs. There are numerous reports indicating the difficulty of predicting clinical infection in patients with positive blood cultures with this organism. No reliable phenotypic or genotypic algorithms currently exist to predict the pathogenicity of a S. epidermidis bloodstream infection. This review will discuss the latest advances in identification methods, global population structure, pathogenicity, biofilm formation, antimicrobial resistance and clinical significance of the detection of S. epidermidis in blood cultures. Previous studies that have attempted to discriminate between invasive and contaminating strains of S. epidermidis in blood cultures will be analyzed.

Glycopeptide antibiotics: evolving resistance, pharmacology and adverse event profile

The first glycopeptide antibiotic was vancomycin, isolated from the soil in the 1950s; since then, the class has expanded to include teicoplanin and the new semisynthetic glycopeptides dalbavancin, oritavancin and telavancin. They are bactericidal, active against most Gram-positive organisms, and in a concentration-dependent manner, inhibit cell wall synthesis. Resistance to vancomycin has emerged, especially among enterococci and Staphylococcus aureus through a variety of mechanisms. This emerging resistance to vancomycin makes proper dosing and monitoring of the area under the curve/MIC critically important. The chief adverse effect of vancomycin is nephrotoxicity, which is also intricately related to its dose. The efficacy of the semisynthetic glycopeptides has been demonstrated in skin and soft-tissue infections, but remains to be seen in serious methicillin-resistant Staphylococcus aureus infections.

Adherence to the 2009 consensus guidelines for vancomycin dosing and monitoring practices: a cross-sectional survey of U.S. hospitals

STUDY OBJECTIVES

To describe the implementation of vancomycin dosing and monitoring practices recommended by the consensus guidelines in a diverse sample of hospitals, and to identify needs for quality improvement and research.

DESIGN

Cross-sectional study using an online survey instrument.

SETTING

Making a Difference in Infectious Diseases Pharmacotherapy (MAD-ID) Research Network.

PARTICIPANTS

A total of 163 respondents from MAD-ID who work in antimicrobial stewardship and represent unique hospitals.

MEASUREMENTS AND MAIN RESULTS

The survey population represented a wide range of patient populations (96% adult, 49% pediatric, and 23% long-term care) and settings (52% not-for-profit nonuniversity, 31% university based, and 11% for profit). Automatic consultation of pharmacy services for all vancomycin dosing was reported in 51% of the institutions. Among the dosing and monitoring practices endorsed by the consensus guidelines, participant institutions commonly followed these recommendations: use of trough concentrations without peak concentrations, maintenance of trough concentration higher than 10 mg/L, and target trough concentrations of 15-20 mg/L for complicated infections. In contrast, there was less consistent application of appropriate timing of trough concentrations, use of loading doses, and use of actual body weight. The remaining challenges and controversies surrounding vancomycin dosing are discussed.

CONCLUSION

Despite the availability of consensus guideline recommendations, practices for dosing and monitoring of vancomycin are not universally applied. The findings of this survey highlight many opportunities for future research and quality improvement strategies.

Analysis of vancomycin therapeutic drug monitoring trends at pediatric hospitals

BACKGROUND

Vancomycin treatment failures in adults with methicillin-resistant Staphylococcus aureus bacteremia are well documented despite established therapeutic monitoring consensus recommendations. Vancomycin use in children has unique challenges, and consensus guidelines are lacking. We evaluated trends in vancomycin monitoring in children and estimated the impact of adult guidelines on patterns of vancomycin use.

METHODS

A retrospective, descriptive study was designed. Data were obtained from the Pediatric Health Information System from 40 not-for-profit, tertiary care pediatric hospitals in the United States. Patients receiving vancomycin during hospitalizations ending July 1, 2007 through June 30, 2011 were included, and the number of vancomycin monitoring determinations per course of therapy was queried. Vancomycin utilization and monitoring practices were evaluated across institutions, age groups and time intervals.

RESULTS

A total of 104,586 patients met study criteria. The mean duration of vancomycin administration was 5 (median 3, range 1-257) days. A mean of 1 (median 1, range 0-186) serum vancomycin concentration was obtained per patient; 46% of patients had none. Eighty-one percent of those receiving vancomycin more than 3 days had monitoring performed at least once. Monitoring practices did not correlate with length of therapy (r² = 0.11). Monitoring frequency increased across all age groups (P < 0.05) after publication of adult guidelines in January 2009.

CONCLUSIONS

Vancomycin monitoring practices are highly variable in children admitted to pediatric hospitals. The frequency with which serum vancomycin concentrations were monitored in children increased after the publication of the adult guidelines. Pediatric consensus guidelines should be developed to optimize patient care and resource utilization.