Efficacy and safety of piperacillin/tazobactam versus biapenem in late elderly patients with nursing- and healthcare-associated pneumonia

Population Pharmacokinetics of Piperacillin/Tazobactam Across the Adult Lifespan

BACKGROUND AND OBJECTIVE

Piperacillin/tazobactam is one of the most frequently used antimicrobials in older adults. Using an opportunistic study design, we evaluated the pharmacokinetics of piperacillin/tazobactam as a probe drug to evaluate changes in antibacterial drug exposure and dosing requirements, including in older adults.

METHODS

A total of 121 adult patients were included. The population pharmacokinetic models that best characterized the observed plasma concentrations of piperacillin and tazobactam were one-compartment structural models with zero-order input and linear elimination.

RESULTS

Among all potential covariates, estimated creatinine clearance had the most substantial impact on the elimination clearance for both piperacillin and tazobactam. After accounting for renal function and body size, there was no remaining impact of frailty on the pharmacokinetics of piperacillin and tazobactam. Monte Carlo simulations indicated that renal function had a greater impact on the therapeutic target attainment than age, although these covariates were highly correlated. Frailty, using the Canadian Study of Health and Aging Clinical Frailty Scale, was assessed in 60 patients who were ≥ 65 years of age.

CONCLUSIONS

The simulations suggested that adults ≤ 50 years of age infected with organisms with higher minimum inhibitory concentrations may benefit from continuous piperacillin/tazobactam infusions (12 g/day of piperacillin component) or extended infusions of 4 g every 8 hours. However, for a target of 50% fT + minimum inhibitory concentration, dosing based on renal function is generally preferable to dosing by age, and simulations suggested that patients with creatinine clearance ≥ 120 mL/min may benefit from infusions of 4 g every 8 hours for organisms with higher minimum inhibitory concentrations.

Evaluation of the risk of acute kidney injury with the use of piperacillin/tazobactam among adult critically ill patients

PURPOSE

Piperacillin/tazobactam (PT), when combined with vancomycin, is associated with an increased risk of acute kidney injury (AKI). It is not known whether PT alone is associated with a higher incidence of AKI compared to other β-lactams among critically ill patients. The objective of this study was to compare the incidence of AKI associated with the use of PT to other β-lactams among adult critically ill patients METHODS: This retrospective study was conducted in the surgical and the medical intensive care units at two hospitals within Hamad Medical Corporation (HMC) in Qatar and included adult critically ill patients who received at least one dose of anti-pseudomonal β-lactams. The primary outcome was acute kidney injury, defined using the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Multiple logistic regression with adjustment for pre-specified potential confounders was used for the primary outcome analysis.

RESULTS

A total of 669 patients were included in the analysis: 507 patients in the PT group and 162 patients in the control (meropenem/cefepime) group. AKI occurred in 136 (26.8%) members of the PT group and 38 (23.5%) members of the control group [odds ratio (OR) 1.2; 95% confidence interval (CI) 0.79-1.8]. The results were not significantly altered after adjusting for the pre-specified potential confounders (adjusted OR 1.38; 95% CI 0.88-2.15).

CONCLUSION

In this study, PT was not associated with a higher risk of AKI compared to cefepime or meropenem among adult critically ill patients.

Piperacillin/tazobactam vs carbapenems for patients with bacterial infection: Protocol for a systematic review

INTRODUCTION

Early empirical broad-spectrum antimicrobial therapy is recommended for patients with severe infections, including sepsis. β-lactam/β-lactamase inhibitor combinations or carbapenems are often used to ensure coverage of likely pathogens. Piperacillin/tazobactam is proposed as a carbapenem-sparing agent to reduce the incidence of multidrug-resistant bacteria and superinfections. In the recently published MERINO trial, increased mortality from piperacillin/tazobactam was suggested in patients with bacteraemia with resistant Escherichia coli or Klebsiella species. Whether these findings also apply to empirical piperacillin/tazobactam in patients with other severe infections, including sepsis, is unknown. We aim to assess the benefits and harms of empirical and definitive piperacillin/tazobactam vs carbapenems for patients with severe bacterial infections.

METHODS AND ANALYSIS

This protocol has been prepared according to the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols statement, the Cochrane Handbook and the Grading of Recommendations, Assessment, Development, and Evaluation approach. We will include randomised clinical trials assessing piperacillin/tazobactam vs carbapenems in patients with severe bacterial infections of any origin. The primary outcome will be all-cause short-term mortality ≤ 90 days. Secondary outcomes will include all-cause long-term mortality > 90 days, adverse events, quality of life, use of life support, secondary infections, antibiotic resistance, and length of stay. We will conduct meta-analyses, including pre-planned subgroup and sensitivity analyses for all assessed outcomes. The risk of random errors in the meta-analyses will be assessed by trial sequential analysis.

Higher incidence of acute kidney injury in patients treated with piperacillin/tazobactam than in patients treated with cefepime: a single-center retrospective cohort study

Background

Piperacillin/tazobactam (PIPC/TAZ) and cefepime (CFPM) are commonly used for the treatment of nosocomial and healthcare-associated infections. Recent reports have suggested that the incidence of acute kidney injury (AKI) in patients treated with a combination of vancomycin (VCM) and PIPC/TAZ is higher than that in patients treated with CFPM. However, there have been few reports on a comparison of the incidences of AKI in patients treated with PIPC/TAZ monotherapy and patients treated with CFPM. In this study, we investigated whether the incidence of AKI in patients treated with PIPC/TAZ is higher than that in patients treated with CFPM.

Methods

This study was a single-center retrospective observational study. Patients who died during the therapeutic period, patients younger than 18 years of age, and patients undergoing hemodialysis were excluded. Primary outcomes were the incidence of AKI and the AKIN stages defined by the Acute Kidney Injury Network. Secondary outcomes were discontinuation and/or change of antibiotics and initiation of dialysis due to AKI. We also investigated the time to onset and the risk factors of AKI in this population.

Results

There were 163 patients in the PIPC/TAZ group and 103 patients in the CFPM group. The incidence of AKI in patients treated with PIPC/TAZ (8.6%) was significantly higher than that in patients treated with CFPM (0.9%) (odds ratio (OR), 9.53; 95% confidence interval (CI), 1.41–408; p= 0.011). AKI severity was mostly stage 1 in both groups. There was no discontinuation and/or changes of antibiotics and there was no initiation of dialysis in either group. The onset of AKI in the PIPC/TAZ group (median period of 4 days) was earlier than that in the CFPM group. PIPC/TAZ was determined to be an independent risk factor of AKI in multivariate analysis (adjusted OR, 9.56; 95% CI, 1.21–75.3; p = 0.032).

Conclusions

This study showed that the incidence of AKI in patients who received PIPC/TAZ was higher than that in patients who received CFPM. Furthermore, the onset of AKI was earlier in patients who received PIPC/TAZ than in patients who received CFPM. PIPC/TAZ was an independent risk factor of AKI in this study population.

Impact of piperacillin/tazobactam on nephrotoxicity in patients with Gram-negative bacteraemia

Piperacillin/tazobactam (TZP) has been associated with nephrotoxicity in patients receiving vancomycin. Its impact on nephrotoxicity in patients with Gram-negative bacteraemia (GNB) is unclear. This study evaluated the impact of TZP on nephrotoxicity in patients with GNB. This retrospective cohort included patients aged ≥18 years receiving ≥48 h of therapy for bacteraemia due to Escherichia coli, Pseudomonas aeruginosa, Enterobacter, Klebsiella, Acinetobacter or Stenotrophomonas maltophilia from 1/01/2008-8/31/2011. Patients with baseline serum creatinine (SCr) ≥3.5 mg/dL, polymicrobial infection or recurrent bacteraemia were excluded. Nephrotoxicity was defined as a ≥0.5 mg/dL increase in SCr or ≥50% increase from baseline for ≥2 consecutive days. Any variable demonstrating a 10% change in exposure effect was retained in the final model. All variables biologically reasonable causes of nephrotoxicity were also considered for inclusion. The median age of the cohort (n = 292) was 76 years; 38.0% had a cancer diagnosis and ICU residence was common (21.9%). There was no difference in nephrotoxicity incidence based on days of TZP received (0 days, 13.6%; 1-2 days, 14.7%; 3-4 days, 6.9%; ≥5 days, 16.7%; P = 0.71). In multivariable analysis, baseline SCr, total body weight and vasopressor use were independently associated with nephrotoxicity. Duration of TZP was not associated with nephrotoxicity in multivariable analysis (1-2 days, OR = 0.91, 95% CI 0.39-2.12; 3-4 days, OR = 0.48, 95% CI 0.10-2.46; ≥5 days, OR = 0.57, 95% CI 0.11-3.02). In this cohort of GNB patients, duration of TZP was not associated with nephrotoxicity.

[Retrospective Analysis of Factors Decreasing the Efficacy of Tazobactam/Piperacillin for Pneumonia in Elderly Patients]

　Tazobactam/piperacillin (TAZ/PIPC) is an antimicrobial drug agent with a broad spectrum of antibacterial activity and is recommended as first-line therapy for hospital-acquired pneumonia, nursing- and healthcare-associated pneumonia, and other severe pneumonias. Nevertheless, in clinical settings, TAZ/PIPC is not fully effective in the treatment of pneumonia in the elderly. In the present study, we retrospectively investigated the efficacy of TAZ/PIPC for pneumonia in elderly patients and identified factors that reduced its efficacy. Ninety-nine patients (mean age of 83.4 years and no significant difference in the sex ratio) were included in the present study. The efficacy rate of TAZ/PIPC for pneumonia in elderly patients was 81.8%, which was approximately 7 to 10% lower than that in domestic phase III trials. A multivariate analysis identified the complications of chronic respiratory disease as a significant factor attenuating the therapeutic effects of TAZ/PIPC [odds ratio 4.050, 95% confidence interval (CI) 1.008-16.271]. In conclusion, TAZ/PIPC may not be sufficiently effective for pneumonia in elderly patients with the complications of chronic respiratory disease as a background.

Bacterial Pneumonia in Elderly Japanese Populations

Bacterial pneumonia is one of the most important infectious diseases in terms of incidence, effect on quality of life, mortality, and impact on society. Pneumonia was the third leading cause of death in Japan in 2011. In 2016, 119 650 Japanese people died of pneumonia, 96% of whom were aged 65 years and above. The symptoms of pneumonia in elderly people are often atypical. Aspiration pneumonia is seen more frequently than in young people because of swallowing dysfunction in the elderly. The mortality rate is also higher in the elderly than in young people. In Japan, the population is aging at an unprecedented rate, and pneumonia in the elderly will be increasingly important in medicine and medical economics in the future. To manage pneumonia in the elderly, it is important to accurately evaluate its severity, administer appropriate antibiotic treatment, and implement effective preventive measures.

Optimal dosing regimen of biapenem in Chinese patients with lower respiratory tract infections based on population pharmacokinetic/pharmacodynamic modelling and Monte Carlo simulation

In this study, a population pharmacokinetic (PPK) model of biapenem in Chinese patients with lower respiratory tract infections (LRTIs) was developed and optimal dosage regimens based on Monte Carlo simulation were proposed. A total of 297 plasma samples from 124 Chinese patients were assayed chromatographically in a prospective, single-centre, open-label study, and pharmacokinetic parameters were analysed using NONMEN. Creatinine clearance (CLCr) was found to be the most significant covariate affecting drug clearance. The final PPK model was: CL (L/h)=9.89+(CLCr-66.56)×0.049; Vc (L)=13; Q (L/h)=8.74; and Vp (L)=4.09. Monte Carlo simulation indicated that for a target of ≥40% T>MIC (duration that the plasma level exceeds the causative pathogen's MIC), the biapenem pharmacokinetic/pharmacodynamic (PK/PD) breakpoint was 4μg/mL for doses of 0.3g every 6h (3-h infusion) and 1.2g (24-h continuous infusion). For a target of ≥80% T>MIC, the PK/PD breakpoint was 4μg/mL for a dose of 1.2g (24-h continuous infusion). The probability of target attainment (PTA) could not achieve ≥90% at the usual biapenem dosage regimen (0.3g every 12h, 0.5-h infusion) when the MIC of the pathogenic bacteria was 4μg/mL, which most likely resulted in unsatisfactory clinical outcomes in Chinese patients with LRTIs. Higher doses and longer infusion time would be appropriate for empirical therapy. When the patient's symptoms indicated a strong suspicion of Pseudomonas aeruginosa or Acinetobacter baumannii infection, it may be more appropriate for combination therapy with other antibacterial agents.

Clinical effect of biapenem on nursing and healthcare-associated pneumonia (NHCAP)

The clinical effect of Biapenem (BIPM) on Nursing and Healthcare-associated pneumonia (NHCAP) was evaluated. One hundred and three NHCAP patients (Group B: 52 patients, Group C: 51 patients) to whom BIPM was administered were included in this study. Clinical effect, bacteriological effect, and adverse events were examined. Results revealed efficacy in 45 of 52 patients (efficacy rate: 86.5%) of NHCAP Group B, and 43 of 51 patients (efficacy rate: 84.3%) of NHCAP Group C, 88 of 103 patients (efficacy rate: 85.4%) as a whole. As for bacteriological effect, 10 (76.9%) of 13 Pseudomonas aeruginosa strains, 9 (90.0%) of 10 Klebsiella pneumoniae strains, 7 (87.5%) of 8 methicillin-sensitive Staphlococcus aureus strains, and 7 (100%) of 7 Streptococcus pneumonia strains were eradicated. As a whole, 38 (80.9%) of 47 strains were eradicated. Adverse events included drug fever and drug eruption in one patient each, and abnormal laboratory findings, including mild hepatic dysfunction in 18 patients and mild renal dysfunction in 5 patients. Based on the above, it was concluded that BIPM shows excellent clinical effect on NHCAP with fewer adverse events.

Clinical evaluation of the need for carbapenems to treat community-acquired and healthcare-associated pneumonia

Carbapenems have an overall broad antibacterial spectrum and should be protected against from the acquisition of drug resistance. The clinical advantages of carbapenem in cases of pneumonia have not been certified and the need for antipseudomonal antimicrobial agents to treat healthcare-associated pneumonia (HCAP) remains controversial. We introduced an antimicrobial stewardship program for carbapenem and tazobactam/piperacillin use and investigated the effects of this program on the clinical outcomes of 591 pneumonia cases that did not require intensive care unit management, mechanical ventilation or treatment with vasopressor agents [221 patients with community-acquired pneumonia (CAP) and 370 patients with HCAP]. Compared with the pre-intervention period, age, comorbidities and the severity and etiology of pneumonia did not differ during the intervention period. Carbapenems were rarely used during the intervention period in cases of pneumonia (CAP: 12% vs. 1%, HCAP: 13% vs. 1%), while antipseudomonal beta-lactam use was reduced from 33% to 8% among cases with HCAP. This reduction in the rate of carbapenem administration did not have an impact on the prognosis in the cases of CAP, and the in-hospital mortality was lower among the patients with HCAP during the intervention period (15% vs. 5%, p = 0.013). The causes of death in the cases of HCAP were not directly related to pneumonia during the intervention period. The current study shows that carbapenem use can be avoided in cases of CAP or HCAP that are not in a critical condition. The frequent use of antipseudomonal beta-lactams does not improve the clinical outcomes of HCAP.

Amoxicillin plus temocillin as an alternative empiric therapy for the treatment of severe hospital-acquired pneumonia: results from a retrospective audit

A formulary decision was made at a large provider of acute hospital services in Surrey to replace piperacillin/tazobactam with amoxicillin+temocillin for the empiric treatment of severe hospital-acquired pneumonia. This decision was made because the use of broad-spectrum-β-lactam antibiotics is a known risk factor for Clostridium difficile infection (CDI) and for the selection of resistance. After the antibiotic formulary was changed, a retrospective audit was conducted to assess the effect of this change. Data from patients hospitalised between January 2011 and July 2012 for severe hospital-acquired pneumonia and treated empirically with piperacillin/tazobactam or amoxicillin+temocillin were reviewed retrospectively. Clinical characteristics of patients, data related to the episode of pneumonia, clinical success and incidence of significant diarrhoea and CDI were analysed. One hundred ninety-two episodes of severe hospital-acquired pneumonia in 188 patients were identified from hospital records. Ninety-eight patients received piperacillin/tazobactam and 94 amoxicillin+temocillin. At baseline, the two treatment groups were comparable, except that more patients with renal insufficiency were treated with piperacillin/tazobactam. Clinical success was comparable (80 versus 82 %; P = 0.86), but differences were observed between piperacillin/tazobactam and amoxicillin+temocillin for the rates of significant diarrhoea (34 versus 4 %, respectively; P < 0.0001) and for CDI (7 versus 0 %, respectively; P < 0.0028). This preliminary study suggests that the combination amoxicillin+temocillin is a viable alternative to piperacillin/tazobactam for the treatment of severe hospital-acquired pneumonia. This combination appears to be associated with fewer gastrointestinal adverse events. Further studies are needed to evaluate the place of amoxicillin+temocillin as empiric treatment of severe hospital-acquired pneumonia.

Update on the pathogenesis and management of pneumonia in the elderly-roles of aspiration pneumonia

Pneumonia in the elderly results in the highest mortality among cases of community-acquired pneumonia (CAP). The pathophysiology of pneumonia in the elderly is primarily due to aspiration pneumonia (ASP). ASP comprises two pathological conditions: airspace infiltration with bacterial pathogens and dysphagia-associated miss-swallowing. The first-line therapy for the treatment of bacterial pneumonia in the elderly is a narrow spectrum of antibiotics, including sulbactam/ampicillin, which are effective against major lower respiratory infection pathogens and anaerobes. The bacterial pathogens of ASP cases of pneumonia in the elderly are similar to those associated with adult CAP. In addition to an appropriate course of antibiotics, pharmacologic and non-pharmacologic approaches for dysphagia and upper airway management are necessary for the treatment and prevention of pneumonia. Swallowing rehabilitation, oral health care, pneumococcal vaccination, gastroesophageal reflux management, and a head-up position during the night are necessary for the treatment and prevention of repeated episodes of pneumonia in elderly patients. In addition, tuberculosis should always be considered for the differential diagnosis of pneumonia in this patient population.