Incidence of Acute Kidney Injury Among Critically Ill Patients With Brief Empiric Use of Antipseudomonal β-Lactams With Vancomycin

Acute kidney injury with combination vancomycin and piperacillin-tazobactam therapy in the ICU: A retrospective cohort study

Vancomycin and piperacillin-tazobactam are commonly used antibiotics. There is increasing evidence to indicate that these therapies in combination predispose patients to acute kidney injury (AKI). However, studies of intensive care unit (ICU) patients with these antibiotics have produced conflicting results. In this single-centre, retrospective cohort study, data was collected on ICU patients prescribed combination vancomycin and piperacillin-tazobactam (VPT) for at least 48 h, compared with patients prescribed vancomycin with either cefepime or meropenem (VMC) for the same time period. Primary outcome was incidence of AKI; secondary outcomes included a desirability of outcome ranking (DOOR) scale, and association between antibiotic duration and kidney injury. A total of 260 patients were included. AKI was observed in 27% of cases overall. Incidence of AKI was higher with VPT compared with VMC on bivariate (relative risk reduction [RRR] 1.9, 95% confidence interval [CI] 0.9-4.1, P = 0.08) and multivariate (RRR 2.2, 95% CI 1.0-4.9, P = 0.05) analyses. Longer duration of antibiotic therapy was associated with increased rates of AKI independent of which antibiotics were prescribed: RRR 4.9, 95% CI 2.1-11.1, P = <0.001 for 5-6 days compared with <5 days, and RRR 2.3, 95% CI 1.0-5.5, P = 0.05 for >7 days compared with <5 days. This study demonstrated an association between increased risk of nephrotoxicity and combination VPT therapy in ICU patients. The concept remains controversial, with recent suggestions that VPT does not truly cause nephrotoxicity. Given our findings and the weight of previous studies, there is a strong mandate to undertake prospective trials to resolve the issue.

Piperacillin-Tazobactam Added to Vancomycin Increases Risk for Acute Kidney Injury: Fact or Fiction?

Vancomycin and piperacillin-tazobactam are 2 of the most commonly prescribed antibiotics in hospitals. Recent data from multiple meta-analyses suggest that the combination increases the risk for vancomycin-induced kidney injury when compared to alternative viable options. However, these studies are unable to prove biologic plausibility and causality as randomized controlled trials have not been performed. Furthermore, these studies define acute kidney injury according to thresholds of serum creatinine rise. Serum creatinine is not a direct indicator of renal injury, rather a surrogate of glomerular function. More reliable, specific, and sensitive biomarkers are needed to truly define if there is a causal relationship with increased toxicity when piperacillin-tazobactam is added to vancomycin. This viewpoint will explore the available evidence for and against increased acute kidney injury in the setting of vancomycin and piperacillin-tazobactam coadministration.

The Right Time to Safely Re-Evaluate Empirical Antimicrobial Treatment of Hip or Knee Prosthetic Joint Infections

Currently, no guideline provides recommendations on the duration of empirical antimicrobial treatment (EAT) in prosthetic joint infection (PJI). The aim of our study was to describe the time to growth of bacteria involved in PJI, rendering possible decreased duration of EAT. Based on a French multicentre prospective cohort study, culture data from patients with confirmed hip or knee PJI were analysed. For each patient, five samples were processed. Time to positivity was defined as the first positive medium in at least one sample for virulent pathogens and as the first positive medium in at least two samples for commensals. Definitive diagnosis of polymicrobial infections was considered the day the last bacteria were identified. Among the 183 PJIs, including 28 polymicrobial infections, microbiological diagnosis was carried out between Day 1 (D1) and D5 for 96.7% of cases. There was no difference in the average time to positivity between acute and chronic PJI (p = 0.8871). Microbiological diagnosis was given earlier for monomicrobial than for polymicrobial infections (p = 0.0034). When an optimized culture of peroperative samples was carried out, almost all cases of PJI were diagnosed within five days, including polymicrobial infections. EAT can be re-evaluated at D5 according to microbiological documentation.

Mortality, Morbidity, and Costs After Implementation of a Vasopressin Guideline in Medical Intensive Care Patients With Septic Shock: An Interrupted Time Series Analysis

Background: Vasopressin decreases vasopressor requirements in patients with septic shock. However, the optimal norepinephrine dose for initiation or cessation of vasopressin is unclear. Objective: Analyze monthly intensive care unit (ICU) mortality rates 1 year preimplementation and postimplementation of a guideline suggesting a norepinephrine dose of 50 µg/min or more for initiation of vasopressin and early cessation of vasopressin. Methods: This retrospective quasi-experimental study included adult patients with septic shock admitted to the medical ICU of a tertiary care medical center over 2 years. Time periods were evaluated with interrupted time series analysis. Results: A total of 1148 patients were included: 573 patients preguideline and 575 patients postguideline. Group characteristics were well balanced at baseline, except patients postguideline had higher sequential organ failure assessment scores. Postguideline, fewer patients were initiated on vasopressin (305 [53.2%] vs 217 [37.7%], absolute difference -15.5% [95% CI -21.2% to -9.8%]), and the norepinephrine dose at vasopressin initiation was higher (median 25 [interquartile range 18, 40] µg/min vs 40 [22, 52] µg/min; median difference 15 [95% CI 11 to 19] µg/min; P < 0.01). After guideline implementation, there was no evidence for a difference in ICU mortality rate slope (slope change 0.07% [95% CI -0.8% to 1.0%] per month; P 0.87), but the vasoactive cost level decreased by US$183 (95% CI -US$327 to -US$39) per patient immediately after implementation. Conclusion and Relevance: Implementation of a guideline suggesting a high norepinephrine dose threshold for vasopressin initiation and early vasopressin cessation in patients with septic shock appears to be safe and may decrease vasoactive costs.

The association of acute kidney injury with the concomitant use of vancomycin and piperacillin/tazobactam in children: A systematic review and meta-analysis

Concomitant use of vancomycin plus piperacillin/tazobactam (TZP) has been associated with increased risk of acute kidney injury (AKI) in hospitalized adults. In this systematic review and meta-analysis, we searched PubMed and EMBASE for pediatric studies examining this hypothesis, with reference to vancomycin monotherapy or in combination with another beta-lactam antibiotic. Out of 1381 non-duplicate studies, 10 met our inclusion criteria. We performed a random effects meta-analysis, based on crude odds ratios, and we accounted for both quality of included studies and publication bias. In primary analysis, concomitant vancomycin and TZP use yielded a statistically significant association with the development of AKI. More specifically, children with AKI had higher odds to have been exposed to vancomycin plus TZP, in comparison with vancomycin monotherapy (OR 8.15; 95% CI: 3.49-18.99), or vancomycin plus any other beta-lactam antibiotic (OR 3.48; 95% CI: 2.71-4.46). Based on the results of the Newcastle Ottawa Scale quality assessment, a secondary analysis including only higher quality studies (6 out of 10 studies) yielded again higher odds of exposure to vancomycin plus TZP, compared to vancomycin plus another beta-lactam antibiotic (OR 3.76; 95% CI: 2.56-5.51). Notably, even after controlling for possible publication bias our results remained statistically significant (OR 3.09; 95% CI: 2.30-4.14). In conclusion, the concomitant use of vancomycin and TZP could be associated with AKI development and the clinical significance of this potential association needs to be studied further in the pediatric population.

Piperacillin/Tazobactam and Antibiotic-Associated Acute Kidney Injury in Critically Ill Children

BACKGROUND

There continues to be uncertainty about whether piperacillin/tazobactam (TZP) increases the risk of AKI in critically ill pediatric patients. We sought to compare rates of AKI among critically ill children treated with TZP or cefepime, an alternative frequently used in intensive care units, with and without vancomycin.

METHODS

We conducted a retrospective cohort study assessing the risk of AKI in pediatric intensive care unit patients after exposure to vancomycin, TZP, and cefepime, alone or in combination, within 48 hours of admission. The primary outcome was development of stage 2 or 3 AKI or an increase in AKI stage from 2 to 3 within the 6 days after the 48-hour exposure window. Secondary outcomes included lengths of stay, need for RRT, and mortality.

RESULTS

Of 5686 patients included, 494 (8.7%) developed stage 2 or 3 AKI. The adjusted odds of developing AKI after medication exposure were 1.56 for TZP (95% confidence interval [95% CI], 1.23 to 1.99), 1.13 for cefepime (95% CI, 0.79 to 1.64), and 0.86 for vancomycin (95% CI, 0.69 to 1.07). The adjusted odds of developing AKI for vancomycin plus TZP versus vancomycin plus cefepime was 1.38 (95% CI, 0.85 to 2.24).

CONCLUSIONS

Observational data in critically ill children show that TZP use is associated with increased odds of AKI. A weaker, nonsignificant association between vancomycin plus TZP and AKI compared with vancomycin plus cefepime, creates some uncertainty about the nature of the association between TZP and AKI. However, cefepime is an alternative not associated with AKI.

Comparison of acute kidney injury and clinical prognosis of vancomycin monotherapy and combination therapy with beta-lactams in the intensive care unit

Antibiotics induced acute kidney injury (AKI) risk in critically ill patients is not well known. This study aimed to evaluate the AKI development and clinical outcomes in critically ill adult patients treated with vancomycin (VAN) or combined with piperacillin-tazobactam (TZP) or meropenem (MEM). This was a retrospective study on critically ill adult patients who were given VAN, TZP or MEM and maintained for at least 48 h. The risk of AKI development and clinical outcomes were compared using the simple analysis and multivariate logistic regression. Three hundred forty patients were eligible. The incidence of any AKI was significantly higher in patients treated with VAN + TZP than those with VAN + MEM or VAN alone (52.7% vs. 27.7% vs. 25.7%; p < .0001). The adjusted odds of AKI increased 2.43-fold in VAN + TZP versus VAN, but not different in VAN + MEM versus VAN. However, AKI duration and recovery rate were not statistically different. In addition, all-cause death within 30 days after AKI onset was not significantly associated with antibiotic regimens. AKI incidence is higher in critically ill patients administered with VAN + TZP than those with VAN + MEM or VAN. However, no obvious evidence was found to prove that antibiotic-induced AKI leads to poor clinical outcomes.

Utilizing the Patient Care Process to Minimize the Risk of Vancomycin-Associated Nephrotoxicity

Vancomycin-associated acute kidney injury (AKI) is a popular topic in the medical literature with few clear answers. While many studies evaluate the risk of AKI associated with vancomycin, few data are high quality and/or long in duration of follow-up. This review takes the clinician through an approach to evaluate a patient for risk of AKI. This evaluation should include patient assessment, antibiotic prescription, duration, and monitoring. Patient assessment involves evaluating severity of illness, baseline renal function, hypotension/vasopressor use, and concomitant nephrotoxins. Evaluation of antibiotic prescription includes evaluating the need for methicillin-resistant Staphylococcus aureus (MRSA) coverage and/or vancomycin use. Duration of therapy has been shown to increase the risk of AKI. Efforts to de-escalate vancomycin from the antimicrobial regimen, including MRSA nasal swabs and rapid diagnostics, should be used to lessen the likelihood of AKI. Adequate monitoring includes therapeutic drug monitoring, ongoing fluid status evaluations, and a continual reassessment of AKI risk. The issues with serum creatinine make the timely evaluation of renal function and diagnosis of the cause of AKI problematic. Most notably, concomitant piperacillin-tazobactam can increase serum creatinine via tubular secretion, resulting in higher rates of AKI being reported. The few studies evaluating the long-term prognosis of AKI in patients receiving vancomycin have found that few patients require renal replacement therapy and that the long-term risk of death is unaffected for patients surviving after the initial 28-day period.

Incidence of Acute Kidney Injury in Critically Ill Patients Receiving Vancomycin with Concomitant Piperacillin-Tazobactam, Cefepime, or Meropenem

Critically ill patients are frequently treated with empirical antibiotic therapy, including vancomycin and β-lactams. Recent evidence suggests an increased risk of acute kidney injury (AKI) in patients who received a combination of vancomycin and piperacillin-tazobactam (VPT) compared with patients who received vancomycin alone or vancomycin in combination with cefepime (VC) or meropenem (VM), but most studies were conducted predominately in the non-critically ill population. A retrospective cohort study that included 2,492 patients was conducted in the intensive care units of a large university hospital with the primary outcome being the development of any AKI. The rates of any AKI, as defined by the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, were 39.3% for VPT patients, 24.2% for VC patients, and 23.5% for VM patients (P < 0.0001 for both comparisons). Similarly, the incidences of stage 2 and stage 3 AKI were also significantly higher for VPT patients than for the patients in the other groups. The rates of stage 2 and stage 3 AKI, respectively, were 15% and 6.6% for VPT patients, 5.8% and 1.8% for VC patients, and 6.6% and 1.3% for VM patients (P < 0.0001 for both comparisons). In multivariate analysis, the use of vancomycin in combination with piperacillin-tazobactam was found to be an independent predictor of AKI (odds ratio [OR], 2.161; 95% confidence interval [CI], 1.620 to 2.883). In conclusion, critically ill patients receiving the combination of VPT had the highest incidence of AKI compared to critically ill patients receiving either VC or VM.

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.