Evaluation of a daptomycin dose-optimization protocol

Impact on Antibiotic Resistance, Therapeutic Success, and Control of Side Effects in Therapeutic Drug Monitoring (TDM) of Daptomycin: A Scoping Review

Antimicrobial resistance (AR) is a problem that threatens the search for adequate safe and effective antibiotic therapy against multi-resistant bacteria like methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococci (VRE) and Clostridium difficile, among others. Daptomycin is the treatment of choice for some infections caused by Gram-positive bacteria, indicated most of the time in patients with special clinical conditions where its high pharmacokinetic variability (PK) does not allow adequate plasma concentrations to be reached. The objective of this review is to describe the data available about the type of therapeutic drug monitoring (TDM) method used and described so far in hospitalized patients with daptomycin and to describe its impact on therapeutic success, suppression of bacterial resistance, and control of side effects. The need to create worldwide strategies for the appropriate use of antibiotics is clear, and one of these is the performance of therapeutic drug monitoring (TDM). TDM helps to achieve a dose adjustment and obtain a favorable clinical outcome for patients by measuring plasma concentrations of an administered drug, making a rational interpretation guided by a predefined concentration range, and, thus, adjusting dosages individually.

Comparison of Antibiotic Dosing Before and After Implementation of an Electronic Order Set

BACKGROUND

To maximize resources, the antimicrobial stewardship program at a pediatric tertiary care hospital made pediatric dosing specific guidance within the electronic health record available to all hospitals within the health system.

OBJECTIVE

The objective of this study was to compare the appropriateness of antibiotic dosing before and after the implementation of an electronic intravenous (IV) antibiotic order set.

METHODS

This was a retrospective cohort study evaluating orders from patients younger than 18 years who received cefepime, piperacillin-tazobactam, tobramycin, or gentamicin at 12 health-system hospitals. Antibiotic dosing regimens and order set use were evaluated in patients who received the specified antibiotics during the 6-month time frame prior to and following electronic order set availability at each hospital.

RESULTS

In the before and after implementation periods, 360 and 387 total antibiotic orders were included, respectively. Most orders were gentamicin (55.8% in the before implementation period and 54.5% in the after implementation period) followed by piperacillin-tazobactam (22.5% in the before period and 22.2% in the after period). Overall, 663 orders were classified as appropriate (88.8%). Appropriateness was similar in the before or after implementation periods (87.8 vs. 89.7%, p = 0.415). There was a significant difference in appropriateness if a blank order versus the electronic IV antibiotic order set was used (82.8 vs. 90.5%; p = 0.024).

CONCLUSION

No difference in antibiotic appropriateness overall was found in the before and after implementation periods. However, when specifically compared with the appropriateness of dosing when blank order forms were used, dosing was more appropriate when electronic antibiotic order sets were used.

Feasibility and applicability of antimicrobial stewardship in immunocompromised patients

PURPOSE OF REVIEW

Antimicrobial stewardship is the primary intervention in the battle against antimicrobial resistance, but clinicians do not always apply many key antimicrobial stewardship principles to patients with significant immune defects due to lack of data and fear of bad outcomes. We review evidence regarding the application of stewardship principles to immunocompromised patients, with a focus on solid organ and hematopoietic stem cell transplant recipients.

RECENT FINDINGS

Antimicrobial stewardship programs (ASPs), targeting immunocompromised patient populations such as oncology and transplant, are gaining traction. Emerging literature suggests that several stewardship interventions can be adapted to immunocompromised hosts and improve antimicrobial utilization, but data supporting improved outcomes is very limited.

SUMMARY

The application of antimicrobial stewardship principles to immunocompromised patients is feasible, necessary, and urgent. As antimicrobial stewardship programs gain momentum across a diverse range of healthcare settings more immunocompromised patients will fall under their purview. It is imperative that centers applying antimicrobial stewardship principles share their experience and establish collaborative research efforts to advance our knowledge base in applying antimicrobial stewardship initiatives to immunocompromised host populations, both in terms of programmatic success and patient outcomes.

Evaluation of a standardized daptomycin dosing nomogram

PURPOSE

Implementation of a standardized daptomycin dosing protocol in a community teaching hospital to determine potential cost savings, effectiveness, and safety is presented.

METHODS

A retrospective review of randomly selected patients receiving daptomycin therapy from October 2013 to January 2014 was performed to establish a preimplementation patient control group. A specific time for preparing daptomycin in the i.v. room was used based on a standardized administration time of 4 p.m. Reconstituted doses were stored for up to 48 hours in the refrigerator in plastic syringes. All daptomycin doses were given by rapid i.v. administration. For all patients who received daptomycin, the protocol specified that a baseline creatine phosphokinase level be evaluated within 24 hours of the start date and on day 3, day 7, and weekly thereafter until daptomycin therapy was completed or discontinued.

RESULTS

The most frequent indications for daptomycin use preimplementation and postimplementation were related to catheter use or persistent bacteremia and skin and soft tissue infections. Through the implementation of the standardized dosing nomogram and optimization of i.v. room workflow, the amount of waste decreased by 21,500 mg and generated a savings of $13,845 over the course of the four-month study period, which can be extrapolated to $41,535 annually. The infection cure rate at completion of therapy was 56.7% in the preimplementation population compared with 70.0% in the postimplementation population. Daptomycin was well tolerated at the standardized doses used in the study.

CONCLUSION

Implementation of a standardized dosing nomogram reduced the amount of daptomycin wasted and resulted in cost savings. The standardized dosing nomogram did not impair the rate of clinical effectiveness or cause adverse events.

Antimicrobial Stewardship Intervention and Feedback to Infectious Disease Specialists: A Case Study in High-Dose Daptomycin

Infectious Diseases specialists have used high-dose daptomycin (≥6 mg/kg/day) in select patients with difficult to treat methicillin-resistant Staphylococcus aureus (MRSA) or vancomycin-resistant Enterococcus (VRE) infections to optimize outcomes. Antimicrobial stewardship programs enforce antimicrobial formulary restrictions; however, interventions specifically aimed at Infectious Disease specialists can be particularly challenging. The purpose of this study was to create a high-dose daptomycin algorithm for Infectious Disease specialists that are consistent with best-practices. Daptomycin prescribing habits pre- and post-daptomycin algorithm implementation were evaluated using a quasi-experimental study design. Patients were included if ≥18 years of age and received daptomycin for ≥48 h. Patients were excluded if daptomycin was initiated on an outpatient setting. During the 12-month pre-intervention phase, 112 patients were included, with 73 patients in the 12-month post-intervention phase. A statistically significant decrease in the mean daptomycin dose from 9.01 mg/kg to 7.51 mg/kg (p < 0.005) was observed, resulting in an annual drug cost-savings of over $75,000 without adversely affecting readmission rates due to infection. Creation of a daptomycin algorithm with consideration of pathogen, disease state, and prior treatment, is an effective means of influencing prescribing habits of Infectious Disease specialists.

Evaluation of the Treatment of Vancomycin-Resistant Enterococcal Urinary Tract Infections in a Large Academic Medical Center

BACKGROUND:

Vancomycin-resistant enterococci (VRE) are a common cause of nosocomial urinary tract infections (UTIs) among hospitalized patients. Clinicians need to differentiate between VRE-associated urinary colonization, asymptomatic bacteriuria, and UTIs to determine the need for treatment and length of therapy.

OBJECTIVE:

To characterize the diagnosis and management of VRE from urinary sources, including compliance with institutional treatment guidelines, and identify risk factors associated with clinical failure.

METHODS:

We performed a retrospective, single-center, cohort study among patients with VRE-positive cultures from urinary sources over a 3-year study period (July 2008-September 2011). Descriptive statistics were used to evaluate demographics, diagnostics, guideline compliance, pharmacotherapy, and outcomes. Risk factors associated with clinical failure were identified by multivariate logistic regression analysis.

RESULTS:

Two hundred sixty-nine distinct episodes of VRE met inclusion criteria among 252 patients. Forty-seven percent and 77% of episodes occurred in patients admitted to an intensive care unit and hospitalized for 7 or more days, respectively. Fifty-eight percent of the episodes were classified as asymptomatic bacteriuria or colonization. Compliance with institutional treatment guidelines for the appropriate drug, dose, and duration occurred in approximately 70% of the cases. Among noncompliant cases (n = 83), 48 (58%) were overtreated, and 35 (42%) were undertreated. Clinical failure among all cases was common, including mortality (17.1%). Factors independently associated with clinical failure determined on multivariate analysis included weight 100 kg or more (OR 5.30; 95% CI 1.42–12.21; p = 0.014), renal disease (OR 2.57; 95% CI 1.02–6.47; p = 0.048), indwelling catheter (OR 4.62; 95% CI 1.05–18.24; p = 0.046), and VRE bloodstream infection (OR 15.71; 95% CI 2.9–128.7; p < 0.001).

CONCLUSIONS:

Improved education is needed to minimize cases of overtreatment and undertreatment of VRE-associated UTIs and decrease inappropriate drug-related costs and clinical failure rates. Risk factors for clinical failure can be used to risk stratify VRE-associated UTIs and further guide treatment decisions.