Determination of alternative ceftolozane/tazobactam dosing regimens for patients with infections due to Pseudomonas aeruginosa with MIC values between 4 and 32 mg/L.

Background: Optimization of the antibiotics for patients with infections due to MDR Pseudomonas aeruginosa (MDR-PA) often requires consideration of alternate dose and infusion times that can be influenced by renal function. Objectives: We sought to identify ceftolozane/tazobactam dosing schemes that optimized the probability of target attainment (PTA) against infections due to MDR-PA with ceftolozane/tazobactam MICs between 4 and 32 mg/L across different categories of renal function. Methods: A prior validated ceftolozane/tazobactam population pharmacokinetic model was used for Monte Carlo simulation of 128 alternate permutations of dose, infusion time and renal function in 5000 cases/permutation. Four ceftolozane/tazobactam doses (250/125 mg to 2/1 g) every 8 h with infusion durations of 1-7 h and as continuous infusions were simulated. The model simulated ceftolozane/tazobactam clearance as a function of creatinine clearance (CLCR) within four categories of estimated renal function: 15-29, 30-50, 51-120 and 121-180 mL/min. The PTA was benchmarked on 40% free ceftolozane/tazobactam concentration time above the MIC. Results: The 512 alternate scenarios identified the current ceftolozane/tazobactam dose of 1/0.5 g to be optimal for MICs ≤32 mg/L (CLCR 15-50 mL/min), ≤16 mg/L (CLCR 51-120 mL/min) and ≤8 mg/L (CLCR 121-180 mL/min). Extended infusion of 4-5 h had a higher PTA than shorter and continuous infusions in simulations of augmented renal clearance across infections with MICs of 4-32 mg/L. Conclusions: Extended infusion ceftolozane/tazobactam regimens should be investigated as a potential dosing solution to improve the PTA against infections due to MDR-PA with higher ceftolozane/tazobactam MICs.

The burden of neutropenic sepsis in patients with advanced non-small cell lung cancer treated with single-agent docetaxel: A retrospective study.

OBJECTIVES: To describe rates of confirmed and suspected neutropenic sepsis (NS) and associated hospital resource utilisation in patients with non-small cell lung cancer (NSCLC) treated with docetaxel monotherapy following relapse after ≥1 line of chemotherapy in routine UK clinical practice. MATERIALS AND METHODS: A multi-centre, retrospective, observational research study was conducted in seven centres across England and Wales. Adult patients with stage III/IV NSCLC initiated on docetaxel monotherapy between 2010 and 2016 in routine clinical practice (aged ≥18 years at initiation) following failure of first-line chemotherapy were eligible. Data were collected from hospital medical records between May 2016 and July 2016, on all episodes of confirmed or suspected NS related to docetaxel monotherapy, including patient characteristics. Episodes of confirmed NS were defined as documented absolute neutrophil count <1.0×109/L, plus temperature >38°C or other signs/symptoms of sepsis, otherwise episodes were classified as suspected NS. RESULTS: 121 patients were included (median age 65.5 years; 57.9% male; median 4.0 cycles of docetaxel; 19.8% treated with prophylactic granulocyte-colony stimulating factor). Episodes of confirmed or suspected NS were recorded in 21/121 (17.4%) patients (11 confirmed episodes in 11 [9.1%] patients and 11 suspected episodes in 10 [8.3%] patients). Resource utilisation data were available for 21/22 episodes; the mean length of stay for confirmed NS admissions (n=11) was 9.2 (SD: 9.2) days and for suspected NS admissions (n=10) was 4.7 (SD: 4.6) days. The most commonly prescribed treatment for NS was piperacillin/tazobactam therapy (46.5% of all documented treatments). The mean total costs of managing patients with confirmed NS (n=11) and suspected NS (n=9) were £3163 (SD: £2921) and £1790 (SD: £1585) per patient, respectively. CONCLUSION: Rates of confirmed NS in UK clinical practice were broadly similar to those reported in clinical trials; however, the burden of suspected NS, not routinely reported elsewhere, is also substantial.

Using Population Pharmacokinetic Modeling and Monte Carlo Simulations To Determine whether Standard Doses of Piperacillin in Piperacillin-Tazobactam Regimens Are Adequate for the Management of Febrile Neutropenia.

Changes in the pharmacokinetics of piperacillin in febrile neutropenic patients have been reported to result in suboptimal exposures. This study aimed to develop a population pharmacokinetic model for piperacillin and perform dosing simulation to describe optimal dosing regimens for hematological malignancy patients with febrile neutropenia. Concentration-time data were obtained from previous prospective observational pharmacokinetic and interventional therapeutic drug monitoring studies. Nonparametric population pharmacokinetic analysis and Monte Carlo dosing simulations were performed with the Pmetrics package for R. A two-compartment model, with between-subject variability for clearance (CL), adequately described the data from 37 patients (21 males, age of 59 ± 12 years [means ± standard deviations] and weight of 77 ± 16 kg). Parameter estimates were CL of 18.0 ± 4.8 liters/h, volume of distribution of the central compartment of 14.3 ± 7.3 liters, rate constant for piperacillin distribution from the central to peripheral compartment of 1.40 ± 1.35 h-1, and rate constant for piperacillin distribution from the peripheral to central compartment of 4.99 ± 7.81 h-1 High creatinine clearance (CLCR) was associated with reduced probability of target attainment (PTA). Extended and continuous infusion regimens achieved a high PTA of >90% for an unbound concentration of piperacillin remaining above the MIC (fT>MIC) of 50%. Only continuous regimens achieved >90% PTA for 100% fT>MIC when CLCR was high. The cumulative fraction of response (FTA, for fractional target attainment) was suboptimal (<85%) for conventional regimens for both empirical and directed therapy considering 50% and 100% fT>MIC FTA was maximized with prolonged infusions. Overall, changes in piperacillin pharmacokinetics and the consequences on therapeutic dosing requirements appear similar to those observed in intensive care patients. Guidelines should address the altered dosing needs of febrile neutropenic patients exhibiting high CLCR or with known/presumed infections from high-MIC bacteria.

Cost-effectiveness of ceftolozane/tazobactam plus metronidazole compared with piperacillin/tazobactam as empiric therapy for the treatment of complicated intra-abdominal infections based on the in-vitro surveillance of bacterial isolates in the UK.

AIMS: An increase in the prevalence of antimicrobial resistance among gram-negative pathogens has been noted recently. A challenge in empiric treatment of complicated intra-abdominal infection (cIAI) is identifying initial appropriate antibiotic therapy, which is associated with reduced length of stay and mortality compared with inappropriate therapy. The objective of this study was to assess the cost-effectiveness of ceftolozane/tazobactam + metronidazole compared with piperacillin/tazobactam (commonly used in this indication) in the treatment of patients with cIAI in UK hospitals. METHODS: A decision-analytic Monte Carlo simulation model was used to compare costs (antibiotic and hospitalization costs) and quality-adjusted life years (QALYs) of patients infected with gram-negative cIAI and treated empirically with either ceftolozane/tazobactam + metronidazole or piperacillin/tazobactam. Bacterial isolates were randomly drawn from the Program to Assess Ceftolozane/Tazobactam Susceptibility (PACTS) database, a surveillance database of non-duplicate bacterial isolates collected from patients in the UK infected with gram-negative pathogens. Susceptibility to initial empiric therapy was based on the measured susceptibilities reported in the PACTS database. RESULTS: Ceftolozane/tazobactam + metronidazole was cost-effective when compared with piperacillin/tazobactam, with an incremental cost-effectiveness ratio (ICER) of £4,350/QALY and 0.36 hospitalization days/patient saved. Costs in the ceftolozane/tazobactam + metronidazole arm were £2,576/patient, compared with £2,168/patient in the piperacillin/tazobactam arm. The ceftolozane/tazobactam + metronidazole arm experienced a greater number of QALYs than the piperacillin/tazobactam arm (14.31/patient vs 14.21/patient, respectively). Ceftolozane/tazobactam + metronidazole remained cost-effective in one-way sensitivity and probabilistic sensitivity analyses. CONCLUSIONS: Economic models can help to identify the appropriate choice of empiric therapy for the treatment of cIAI. Results indicated that empiric use of ceftolozane/tazobactam + metronidazole is cost-effective vs piperacillin/tazobactam in UK patients with cIAI at risk of resistant infection. This will be valuable to commissioners and clinicians to aid decision-making on the targeting of resources for appropriate antibiotic therapy under the premise of antimicrobial stewardship.

Cost-effectiveness of ceftolozane/tazobactam compared with piperacillin/tazobactam as empiric therapy based on the in-vitro surveillance of bacterial isolates in the United States for the treatment of complicated urinary tract infections.

BACKGROUND: A challenge in the empiric treatment of complicated urinary tract infection (cUTI) is identifying the initial appropriate antibiotic therapy (IAAT), which is associated with reduced length of stay and mortality compared with initial inappropriate antibiotic therapy (IIAT). We evaluated the cost-effectiveness of ceftolozane/tazobactam compared with piperacillin/tazobactam (one of the standard of care antibiotics), for the treatment of hospitalized patients with cUTI. METHODS: A decision-analytic Monte Carlo simulation model was developed to compare the costs and effectiveness of empiric treatment with either ceftolozane/tazobactam or piperacillin/tazobactam in hospitalized adult patients with cUTI infected with Gram-negative pathogens in the US. The model applies the baseline prevalence of resistance as reported by national in-vitro surveillance data. RESULTS: In a cohort of 1000 patients, treatment with ceftolozane/tazobactam resulted in higher total costs compared with piperacillin/tazobactam ($36,413 /patient vs. $36,028/patient, respectively), greater quality-adjusted life years (QALYs) (9.19/patient vs. 9.13/patient, respectively) and an incremental cost-effectiveness ratio (ICER) of $6128/QALY. Ceftolozane/tazobactam remained cost-effective at a willingness to pay of $100,000 per QALY compared to piperacillin/tazobactam over a range of input parameter values during one-way and probabilistic sensitivity analysis. CONCLUSIONS: Model results show that ceftolozane/tazobactam is likely to be cost-effective compared with piperacillin/tazobactam for the empiric treatment of hospitalized cUTI patients in the United States.

Using a simple point-prevalence survey to define appropriate antibiotic prescribing in hospitalised children across the UK.

BACKGROUND: The National Health Service England, Commissioning for Quality and Innovation for Antimicrobial Resistance (CQUIN AMR) aims to reduce the total antibiotic consumption and the use of certain broad-spectrum antibiotics in secondary care. However, robust baseline antibiotic use data are lacking for hospitalised children. In this study, we aim to describe, compare and explain the prescription patterns of antibiotics within and between paediatric units in the UK and to provide a baseline for antibiotic prescribing for future improvement using CQUIN AMR guidance. METHODS: We conducted a cross-sectional study using a point prevalence survey (PPS) in 61 paediatric units across the UK. The standardised study protocol from the Antibiotic Resistance and Prescribing in European Children (ARPEC) project was used. All inpatients under 18 years of age present in the participating hospital on the day of the study were included except neonates. RESULTS: A total of 1247 (40.9%) of 3047 children hospitalised on the day of the PPS were on antibiotics. The proportion of children receiving antibiotics showed a wide variation between both district general and tertiary hospitals, with 36.4% ( 95% CI 33.4% to 39.4%) and 43.0% (95% CI 40.9% to 45.1%) of children prescribed antibiotics, respectively. About a quarter of children on antibiotic therapy received either a medical or surgical prophylaxis with parenteral administration being the main prescribed route for antibiotics (>60% of the prescriptions for both types of hospitals). General paediatrics units were surprisingly high prescribers of critical broad-spectrum antibiotics, that is, carbapenems and piperacillin-tazobactam. CONCLUSIONS: We provide a robust baseline for antibiotic prescribing in hospitalised children in relation to current national stewardship efforts in the UK. Repeated PPS with further linkage to resistance data needs to be part of the antibiotic stewardship strategy to tackle the issue of suboptimal antibiotic use in hospitalised children.

Evaluation Outcomes Associated with Alternative Dosing Strategies for Piperacillin/Tazobactam: A Systematic Review and Meta-Analysis.

A better dosing strategy can improve clinical outcomes for patients. We systematically reviewed the literatures to determine whether any clinical benefits exist for piperacillin/tazobactam by extended or continuous infusion. Methods - A search of PubMed, Web of Science, ProQuest, ScienceDirect, Cochrane, Embase and related ICAAC and ACCP conferences were conducted up to September 5, 2015. Randomized controlled and observational studies that compared extended or continuous infusion with conventional intermittent infusion of piperacillin/tazobactam were identified from the databases above and analyzed. Two reviewers independently evaluated the methodology and extracted data from primary studies. A meta-analysis was performed using Revman 5.2 software. The quality of each study was assessed. Sensitivity analysis and publication bias were evaluated. Results - Three randomized controlled trials and twelve observational studies were included in this study. All included studies had high quality and no publication bias was found. Compared to the conventional intermittent infusion approach, the extended or continuous infusion group had a significant cost effectiveness (OR -0.89.02, CI (-114.69,-63.35), P<0.00001). No statistical difference was observed for clinical cure rate (OR 1.64, 95% CI (0.88, 3.30), P=0.12) between the two dosing regimens. The sensitivity analysis showed the results were stable. Conclusions - Our systematic review and meta-analysis found that the outcomes associated with alternative dosing strategies of piperacillin/tazobactam have changed compared with conclusions before for several literatures with large samples published. Further data on the outcomes should be generated for a better understanding of the extended or continuous infusion strategy. On the whole, our meta-analysis suggested that the extended or continuous infusion should be recommended for clinical use only considering its economic advantage, but there was no significantly higher clinical cure rate and lower mortality rate compared with the conventional intermittent infusion. This article is open to POST-PUBLICATION REVIEW. Registered readers (see "For Readers") may comment by clicking on ABSTRACT on the issue's contents page.

Nonoperative treatment of acute appendicitis in children: A feasibility study.

PURPOSE: Nonoperative treatment of acute appendicitis appears to be feasible in adults. It is unclear whether the same is true for children. METHODS: Children 5-18 years with <48 h symptoms of acute appendicitis were offered nonoperative treatment: 2 doses of piperacillin IV, then ampicillin/clavulanate ×1 week. Treatment failure (worsening on therapy) and recurrence (after completion of therapy) were noted. Patients who declined enrollment were asked to participate as controls. Cost-utility analysis was performed using Pediatric Quality of Life Scale (PedsQL®) to calculate quality-adjusted life month (QALM) for study and control patients. RESULTS: Twenty-four patients agreed to undergo nonoperative management, and 50 acted as controls. At a mean follow-up of 14 months, three of the 24 failed on therapy, and 2/21 returned with recurrent appendicitis at 43 and 52 days, respectively. Two patients elected to undergo an interval appendectomy despite absence of symptoms. Appendectomy-free rate at one year was therefore 71% (C.I. 50-87%). No patient developed perforation or other complications. Cost-utility analysis shows a 0.007-0.03 QALM increase and a $1359 savings from $4130 to $2771 per nonoperatively treated patient. CONCLUSION: Despite occasional late recurrences, antibiotic-only treatment of early appendicitis in children is feasible, safe, cost-effective and is experienced more favorably by patients and parents.

Effectiveness of Patient Choice in Nonoperative vs Surgical Management of Pediatric Uncomplicated Acute Appendicitis.

IMPORTANCE: Current evidence suggests that nonoperative management of uncomplicated appendicitis is safe, but overall effectiveness is determined by combining medical outcomes with the patient's and family's perspective, goals, and expectations. OBJECTIVE: To determine the effectiveness of patient choice in nonoperative vs surgical management of uncomplicated acute appendicitis in children. DESIGN, SETTING, AND PARTICIPANTS: Prospective patient choice cohort study in patients aged 7 to 17 years with acute uncomplicated appendicitis presenting at a single pediatric tertiary acute care hospital from October 1, 2012, through March 6, 2013. Participating patients and families gave informed consent and chose between nonoperative management and urgent appendectomy. INTERVENTIONS: Urgent appendectomy or nonoperative management entailing at least 24 hours of inpatient observation while receiving intravenous antibiotics and, on demonstrating improvement of symptoms, completion of 10 days of treatment with oral antibiotics. MAIN OUTCOMES AND MEASURES: The primary outcome was the 1-year success rate of nonoperative management. Successful nonoperative management was defined as not undergoing an appendectomy. Secondary outcomes included comparisons of the rates of complicated appendicitis, disability days, and health care costs between nonoperative management and surgery. RESULTS: A total of 102 patients were enrolled; 65 patients/families chose appendectomy (median age, 12 years; interquartile range [IQR], 9-13 years; 45 male [69.2%]) and 37 patients/families chose nonoperative management (median age, 11 years; IQR, 10-14 years; 24 male [64.9%]). Baseline characteristics were similar between the groups. The success rate of nonoperative management was 89.2% (95% CI, 74.6%-97.0%) at 30 days (33 of 37 children) and 75.7% (95% CI, 58.9%-88.2%) at 1 year (28 of 37 children). The incidence of complicated appendicitis was 2.7% in the nonoperative group (1 of 37 children) and 12.3% in the surgery group (8 of 65 children) (P = .15). After 1 year, children managed nonoperatively compared with the surgery group had fewer disability days (median [IQR], 8 [5-18] vs 21 [15-25] days, respectively; P < .001) and lower appendicitis-related health care costs (median [IQR], $4219 [$2514-$7795] vs $5029 [$4596-$5482], respectively; P = .01). CONCLUSIONS AND RELEVANCE: When chosen by the family, nonoperative management is an effective treatment strategy for children with uncomplicated acute appendicitis, incurring less morbidity and lower costs than surgery. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01718275.

Population Pharmacokinetics and Pharmacodynamics of Piperacillin/Tazobactam in Patients with Nosocomial Infections.

OBJECTIVE: The study was to establish a population pharmacokinetic (PPK) model of piperacillin (PIP) and tazobactam (TAZ) that explain pharmacokinetic variability and to propose optimized dosage regimens in patients with nosocomial infections. METHODS: In total, 310 PIP and 280 TAZ concentration-time points were collected at steady state over multiple dosing intervals from 50 patients who received PIP/TAZ infused within 30 min or over 3 h. Drug analysis was performed by high-performance liquid chromatography (HPLC). Nonlinear mixed effects modeling was employed to develop PPK model and 1000 Monte Carlo simulation was used to predict the probability of target attainment (PTA) with a target time of non-protein-bound concentration above MIC > 50 % of the dosing interval. RESULTS: A model with one-compartment model had the best predictive performance for the PPK model. The population estimates of PIP were 13.8 L/h (31.1 %) for clearance (CL) and 21.7 L (38 %) for volume of distribution (V). The population estimates of TAZ were 9.3 L/h (29.1 %) for CL and 16 L (35.3 %) for V. Influence of creatinine clearance (CLcr) and body weight were identified as important covariates for PIP/TAZ CL and V, respectively. A 30-min infusion of 4 g every 6 h achieved robust (≥90 %) PTAs for MIC ≤ 16 mg/L. As an alternative mode of administration, a 3-h infusion of 4 g every 6 h achieved robust PTAs for Pseudomonas aeruginosa and Klebsiella pneumoniae. CONCLUSIONS: Prolonged infusions achieved better PTAs compared with shorter infusions at similar daily doses. This benefit was most pronounced for MICs between 16 and 40 mg/L.

Adherence to European Association of Urology Guidelines on Prophylactic Antibiotics: An Important Step in Antimicrobial Stewardship.

BACKGROUND: The evolution of resistant pathogens is a worldwide health crisis and adherence to European Association of Urology (EAU) guidelines on antibiotic prophylaxis may be an important way to improve antibiotic stewardship and reduce patient harm and costs. OBJECTIVE: To evaluate the prevalence of antibiotic-resistant bacterial strains and health care costs during a period of adherence to EAU guidelines in a tertiary referral urologic institution. DESIGN, SETTING, AND PARTICIPANTS: A protocol for adherence to EAU guidelines for antibiotic prophylaxis for all urologic procedures was introduced in January 2011. Data for 3529 urologic procedures performed between January 2011 and December 2013 after protocol introduction were compared with data for 2619 procedures performed between January 2008 and December 2010 before protocol implementation. The prevalence of bacterial resistance and health care costs were compared between the two periods. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The outcome measures were the proportion of resistant uropathogens and costs related to antibiotic consumption and symptomatic postoperative infection. We used χ2 and Fisher's exact tests to test the significance of differences. RESULTS AND LIMITATIONS: The proportion of patients with symptomatic postoperative infection did not differ (180/3529 [5.1%] vs. 117/2619 [4.5%]; p=0.27). A total of 342 isolates from all patients with symptomatic postoperative infections were analysed. The rate of resistance of Escherichia coli to piperacillin/tazobactam (9.1% vs. 5.4%; p=0.03), gentamicin (18.3% vs. 11.2%; p=0.02), and ciprofloxacin (32.3% vs. 19.1%; p=0.03) decreased significantly after protocol introduction. The defined daily dose (DDD) use of ciprofloxacin fell from 4.2 to 0.2 DDD per 100 patient-days after implementation (p<0.001). Antibiotic drug costs (€76,980 vs. €36,700) and costs related to postoperative infections (€45,870 vs. €29,560) decreased following introduction of the protocol (p<0.001). CONCLUSIONS: Adherence to EAU guidelines on antibiotic prophylaxis reduced antibiotic usage without increasing post-operative infection rate and lowered the prevalence of resistant uropathogens. PATIENT SUMMARY: We analysed the impact of adherence to European Association of Urology guidelines on antibiotic prophylaxis for all surgical urologic procedures on the prevalence of infections and resistant bacterial strains and on costs. We found that adherence to the guidelines reduced the rate of bacterial resistance, in particular against piperacillin/tazobactam, gentamicin, and ciprofloxacin, and reduced costs without increasing the risk of postoperative infection after urologic procedures. We recommend adherence to the guidelines as an important part of antibiotic stewardship programmes.

Population pharmacokinetics of piperacillin in the early phase of septic shock: does standard dosing result in therapeutic plasma concentrations?

Antibiotic dosing in septic shock patients poses a challenge for clinicians due to the pharmacokinetic (PK) variability seen in this patient population. Piperacillin-tazobactam is often used for empirical treatment, and initial appropriate dosing is crucial for reducing mortality. Accordingly, we determined the pharmacokinetic profile of piperacillin (4 g) every 8 h, during the third consecutive dosing interval, in 15 patients treated empirically for septic shock. We developed a population pharmacokinetic model to assess empirical dosing and to simulate alternative dosing regimens and modes of administration. Time above the MIC (T>MIC) predicted for each patient was evaluated against clinical breakpoint MIC for Pseudomonas aeruginosa (16 mg/liter). Pharmacokinetic-pharmacodynamic (PK/PD) targets evaluated were 50% fT>4×MIC and 100% fT>MIC. A population PK model was developed using NONMEM, and data were best described by a two-compartment model. Central and intercompartmental clearances were 3.6 liters/h (relative standard error [RSE], 15.7%) and 6.58 liters/h (RSE, 16.4%), respectively, and central and peripheral volumes were 7.3 liters (RSE, 11.8%) and 3.9 liters (RSE, 9.7%), respectively. Piperacillin plasma concentrations varied considerably between patients and were associated with levels of plasma creatinine. Patients with impaired renal function were more likely to achieve predefined PK/PD targets than were patients with preserved or augmented renal function. Simulations of alternative dosing regimens showed that frequent intermittent bolus dosing as well as dosing by extended and continuous infusion increases the probability of attaining therapeutic plasma concentrations. For septic shock patients with preserved or augmented renal function, dose increment or prolonged infusion of the drug needs to be considered. (This study has been registered at ClinicalTrials.gov under registration no. NCT02306928.).

Penetration of piperacillin-tazobactam into human prostate tissue and dosing considerations for prostatitis based on site-specific pharmacokinetics and pharmacodynamics.

This study aimed to investigate the penetration of PIPC-TAZ into human prostate, and to assess effectiveness of PIPC-TAZ against prostatitis by evaluating site-specific PK-PD. Patients with prostatic hypertrophy (n = 47) prophylactically received a 0.5 h infusion of PIPC-TAZ (8:1.2-0.25 g or 4-0.5 g) before transurethral resection of the prostate. PIPC-TAZ concentrations in plasma (0.5-5 h) and prostate tissue (0.5-1.5 h) were analyzed with a three-compartment PK model. The estimated model parameters were, then used to estimate the drug exposure time above the minimum inhibitory concentration for bacteria (T > MIC, the PD indicator for antibacterial effects) in prostate tissue for six PIPC-TAZ regimens (2.25 or 4.5 g; once, twice, three times or four times daily; 0.5 h infusions). Prostate tissue/plasma ratio of PIPC was about 36% both for the maximum drug concentration (Cmax) and the area under the drug concentration-time curve (AUC). Against MIC distributions for isolates of Escherichia coli, Klebsiella species and Proteus species, regimens of 4.5 g twice daily and 2.25 g three times daily achieved a >90% probability of attaining the bacteriostatic target for PIPC (30% T > MIC) in prostate tissue; regimens of 4.5 g three times daily and 2.25 g four times daily achieved a >90% probability of attaining the bactericidal target for PIPC (50% T > MIC) in prostate tissue. However, against Pseudomonas aeruginosa isolates, none of the tested regimens achieved a >90% probability. PIPC-TAZ is appropriate for the treatment of prostatitis from the site-specific PK-PD perspective.

Clinical and Economic Impact of Empirical Extended-Infusion Piperacillin-Tazobactam in a Community Medical Center.

BACKGROUND: Current medical center practice allows for the automatic conversion of all piperacillin/tazobactam orders from intermittent to extended infusion (EI). OBJECTIVE: To compare the clinical and cost impact of empirical extended-infusion piperacillin/tazobactam. METHODS: All consecutive patients treated with piperacillin/tazobactam for >48 hours were reviewed for inclusion. Patients were stratified into 2 groups: (1) traditional infusion (TI), preprotocol implementation, and (2) EI, postprotocol implementation. Patient demographics and primary and secondary diagnoses were extracted from the hospital discharge database. All patients were assessed for the primary end point of all cause 14-day in-hospital mortality. Secondary outcomes included length of hospital stay, duration of antibiotic therapy, cost per treatment course, and occurrence of Clostridium difficile infection. RESULTS: A total of 2150 patients were included (EI = 632; TI = 1518). After adjusting for comorbidity, length of stay, and age, 14-day in-hospital mortality was similar between groups (odds ratio = 1.16; 95% CI = 0.85-1.58; P = 0.37). Length of stay was similar between the EI group versus TI (mean ± SD: 12.5 ± 9.58 days vs 11.8 ± 9.58 days, respectively; P = 0.10) after adjusting for age and Chalson-Deyo comorbidity index. Total cost per treatment course was reduced in the EI group by 13% compared with the TI group ($565.90 ± $257.70 vs $648.30 ± $349.20, respectively; P < 0.0001). CONCLUSION: Automatic substitution of EI for TI piperacillin/tazobactam is safe and associated with significant cost savings. EI piperacillin/tazobactam was not associated with a reduction in mortality or length of stay.

Impact of a Dynamic Microbiological Environment on the Clinical Efficacy of Ertapenem and Piperacillin/Tazobactam in the Treatment of Complicated Community-Acquired Intra-Abdominal Infection in Spain: A Cost-Consequence Analysis.

BACKGROUND AND OBJECTIVE: The microbial susceptibility of many antibiotics has been affected by prescribing patterns and their extensive use. The purpose of this evaluation was to assess how these changes could affect the initial efficacy of ertapenem and piperacillin/tazobactam in the treatment of complicated intra-abdominal infections (IAIs) acquired in the community and the potential consequences this may have in healthcare costs in Spain. METHODS: The Initial efficacy of ertapenem and piperacillin/tazobactam for patients with APACHE (Acute Physiology and Chronic Health Evaluation) II scores <10 was extracted from a multicenter randomized study and were combined with the current microbial susceptibilities obtained from the SMART study, a multinational surveillance program. Country-specific pathogens distribution was extracted from a national study in patients with community-acquired IAI. The estimated effectiveness was used in a decision-analytic model to compare total costs between ertapenem and piperacillin/tazobactam in the treatment of complicated IAI. The model performs extensive one-way and probabilistic sensitivity analyses. RESULTS: The model suggested a savings of €209 (year 2012 values) per patient when complicated IAIs acquired in the community (APACHE II <10) were treated with ertapenem instead of piperacillin/tazobactam. One-way sensitivity analyses showed length of stay as the key driver parameter. Further analysis of this parameter and probabilistic sensitivity analysis confirmed the robustness of our evaluation, with a 58% likelihood of ertapenem being dominant. CONCLUSIONS: Ertapenem appears to be a cost-saving strategy over piperacillin/tazobactam for the treatment of patients with complicated IAIs acquired in the community in Spain.

Extended-Infusion versus standard-infusion piperacillin-tazobactam for sepsis syndromes at a tertiary medical center.

Piperacillin-tazobactam (PTZ) is frequently used as empirical and targeted therapy for Gram-negative sepsis. Time-dependent killing properties of PTZ support the use of extended-infusion (EI) dosing; however, studies have shown inconsistent benefits of EI PTZ treatment on clinical outcomes. We performed a retrospective cohort study of adult patients who received EI PTZ treatment and historical controls who received standard-infusion (SI) PTZ treatment for presumed sepsis syndromes. Data on mortality rates, clinical outcomes, length of stay (LOS), and disease severity were obtained. A total of 843 patients (662 with EI treatment and 181 with SI treatment) were available for analysis. Baseline characteristics of the two groups were similar, except for fewer female patients receiving EI treatment. No significant differences between the EI and SI groups in inpatient mortality rates (10.9% versus 13.8%; P = 0.282), overall LOS (10 versus 12 days; P = 0.171), intensive care unit (ICU) LOS (7 versus 6 days; P = 0.061), or clinical failure rates (18.4% versus 19.9%; P = 0.756) were observed. However, the duration of PTZ therapy was shorter in the EI group (5 versus 6 days; P < 0.001). Among ICU patients, no significant differences in outcomes between the EI and SI groups were observed. Patients with urinary or intra-abdominal infections had lower mortality and clinical failure rates when receiving EI PTZ treatment. We did not observe significant differences in inpatient mortality rates, overall LOS, ICU LOS, or clinical failure rates between patients receiving EI PTZ treatment and patients receiving SI PTZ treatment. Patients receiving EI PTZ treatment had a shorter duration of PTZ therapy than did patients receiving SI treatment, and EI dosing may provide cost savings to hospitals.

Continuous infusion of piperacillin/tazobactam in patients with severe infections: A possible pharmacokinetic optimisation?

Piperacillin/Tazobactam is a time-dependent antimicrobial combination (beta-lactam/beta-lactamase inhibitor) commonly used in the treatment of severe Gram-negative infections. The optimisation of its time-dependent bactericidal activity via continuous infusion could improve clinical outcomes. Several studies have been realized on the relevance of a continuous infusion, but, to date, no definitive position can be adopted on the matter and a well-designed randomized controlled trial is warranted. In other articles, continuous infusion regimens are also more cost efficient. This article is an update, including the most recent trials about this subject.

The trends in antibiotic use by general dental practitioners in the Czech Republic (2006-2012).

We assessed antibiotic prescribing in practical dentistry in the Czech Republic, as antibiotics are widely prescribed by dental practitioners and warning signals of their overuse can be observed. The individual antibiotic prescriptions were extracted from the database of the General Health Insurance Company and further analysed. The proportion of dentists' prescription within the whole primary health-care sector and the rate of prescriptions of particular antibiotics were both in defined daily doses per 1,000 insurees and day (DID) and in number of prescriptions calculated. The proportion of antibiotic use in dentistry increased from 0.63 DID in 2006 to 0.75 DID. We found a decline in use of narrow-spectrum penicillins by 4.8%, tetracyclines by 3.5% and macrolides by 3.6%, accompanied by increasing rate of prescription of aminopenicillins combined with beta-lactamase inhibitor by 8.9% and lincosamides by 8.5%. The consumption of clindamycin and amoxicillin combined with clavulanate in DID has increased by approximately 60% since 2006 thanks to the exclusive prescribing of two commercial oral products only. Factors contributing to this unfavourable trend are commercial influence or defensive medicine practice.

Clinical response at Day 3 of therapy and economic outcomes in hospitalized patients with acute bacterial skin and skin structure infection (ABSSSI).

OBJECTIVE: The FDA recently issued guidance for the types of infections that should be included in trials to support an indication for antibacterial treatment. The latest FDA guidance recommends assessing response to drug therapy at 48 to 72 hours as the primary endpoint in clinical trials. This study evaluated clinical and economic outcomes among acute bacterial skin and skin structure infections (ABSSSI) patients hospitalized at a 3000-bed healthcare system in New Jersey. RESEARCH DESIGN AND METHODS: In this retrospective cohort analysis, adult ABSSSI patients hospitalized between July 2010 and December 2011 were stratified based on infection type: cellulitis/erysipelas and major cutaneous abscess, wound infection, and all ABSSSI. Initial antibiotic therapy was assessed by individual agent, regimen, and MRSA coverage. Day 3 response to initial antibiotic therapy was evaluated based on temperature and lesion cessation outcomes; clinical response rates were assessed by initial therapy and pathogen for each cohort. The impact of response on length of stay (LOS), cost of care, and antibiotic treatment duration were also evaluated. RESULTS: Commonly used antibiotics included vancomycin, cefazolin, piperacillin-tazobactam, and ampicillin-sulbactam; over 40% of patients received empiric therapy with activity against MRSA. Clinical non-response to initial antimicrobial therapy at Day 3 was 39.9%, 30.3%, and 60.7%, for all ABSSSI, cellulitis/abscess, and wound infection patients, respectively. The cost of care among non-responders was over 1.5 times that of responders (p < 0.0001). Non-response to initial therapy was associated with a 3.7 day increase in duration of antibiotic treatment (p < 0.0001). CONCLUSIONS: Results of this study demonstrate that a significant percentage of ABSSSI patients, particularly those with wound infection, were not achieving clinical response at Day 3 of therapy. Failure to respond to drug therapy is associated with substantial increases in LOS, antibiotic treatment duration, and cost of care. LIMITATIONS: This had the inherent limitations associated with a retrospective chart review; because data was initially collected for clinical rather than research purposes, certain information may have been absent, incomplete, or missed by data abstractors.

Piperacillin-tazobactam as a cost effective monotherapy in febrile neutropenia.

BACKGROUND: Fever in neutropenic patient is a medical emergency. Timely intervention with antibiotics has been demonstrated to be effective. We assessed Piperacillin-Tazobactem as a cost effective mono-therapy in solid malignancy patients in our institution in relation to dual antibiotic therapy and other monotherapies. METHODS: This study was conducted to determine the efficacy, and cost effectiveness of Piperacillin-Tazobactem as monotherapy in febrile neutropenia. Total 150 patients with chemotherapy induced febrile neutropenia were selected. Piperacillin-Tazobactem was given intravenously 4500 mg every 6 hour. Outcome was assessed as success and failure. Success was defined as afebrile for four consecutive days, clearance of signs of infection, no new cultures, and no recurrence of primary infection after completion of therapy. Failure was defined as modification or addition of antibiotic due to clinical deterioration, cultured organism resistant to Piperacillin-Tazobactem and Death. RESULTS: The mean age was 43 years, 31% males and 69% were females. Out of total 150 patients, 73 patients were of breast carcinoma. There were 143 patients with negative blood cultures, and 7 patients with positive blood cultures, out of which 3 patients were resistant to Piperacillin-Tazobactem. Success was achieved in 83.3% of total patients. Daily cost of Piperacillin-Tazobactem was much less in relation to other monotherapies and dual antibiotic therapy including Gentamicin. None of the patient had adverse effects of Piperacillin-Tazobactem. CONCLUSION: We concluded that Piperacillin-Tazobactem is a safe, well tolerated as well as cost effective monotherapy in patient with febrile neutropenia with solid cancers. Only two percent organisms were resistant to Pipercillin-Tazobactam.