Understanding vancomycin nephrotoxicity augmented by β-lactams: a synthesis of endosymbiosis, proximal renal tubule mitochondrial metabolism, and β-lactam chemistry

The recent understanding that hydrophobic β-lactams have greater affinity for organic anion transporter-3 (OAT-3) of the proximal renal tubule could provide valuable insights for anticipating β-lactams that may exacerbate vancomycin-induced nephrotoxicity. Vancomycin alone provides oxidative stress on the highly metabolic proximal tubular cells. Hydrophobic β-lactams (eg, piperacillin and anti-staphylococcal β-lactams) could have greater OAT-3 mediated uptake into proximal tubular cells than hydrophilic β-lactams (eg, most cephalosporins and carbapenems), thereby causing greater mitochondrial stress on these susceptible cells. It remains to be seen whether concomitant drugs that inhibit OAT-3 mediated cellular uptake of β-lactams into proximal tubular cells or provide antioxidant effects might mitigate β-lactam augmented vancomycin nephrotoxicity. Furthermore, the serum creatinine rise seen with vancomycin and hydrophobic β-lactams might represent competition for creatinine-secreting transporters (of which OAT-3 is one), thus, indicating creatinine retention rather than renal injury. In the meantime, clinicians are advised to utilise less nephrotoxic combinations in both empirical and directed antibiotic selection settings until further research is conducted.

Impact of Limiting Vancomycin Loading Doses in Patients With Methicillin-resistant Staphylococcus aureus Infections After Hospital Protocol Revision

Background: Vancomycin loading doses are commonly used to quickly attain target serum concentrations; however, data supporting their effect on clinical patient outcomes is limited. In April 2020, our institution revised our pharmacist-driven vancomycin dosing protocol to reserve loading doses for hemodynamically unstable patients with suspected serious methicillin-resistant Staphylococcus aureus (MRSA) infections. Prior to the protocol update, all patients treated with vancomycin at our institution received a weight-based loading dose. The purpose of this study is to assess clinical efficacy and safety outcomes related to the use of vancomycin loading doses. Methods: A retrospective, quasi-experimental study was performed to compare clinical outcomes in adult patients treated with vancomycin for laboratory-confirmed MRSA infections. Patients who received vancomycin therapy prior to our institution's vancomycin dosing protocol revisions (pre-intervention) were compared to patients who received vancomycin after the revisions (post-intervention). The primary outcome was all-cause, inpatient mortality. Secondary outcomes included persistent signs and symptoms of infection ≥5 days after vancomycin initiation, switch to alternative anti-MRSA therapy, and nephrotoxicity. Results: A total of 122 patients (63 pre-intervention patients and 59 post-intervention patients) were included. Receipt of a vancomycin loading dose did not impact the rate of inpatient mortality (4.76%vs 6.78%; OR 1.46, 95% CI [0.31, 6.79]). All secondary outcomes were similar between the two groups, including persistent signs and symptoms of infection, switch to alternative anti-MRSA therapy, and nephrotoxicity. Conclusions: Routine use of vancomycin loading doses is not associated with improved outcomes in hemodynamically stable patients with MRSA infections.

The Effect of Vancomycin and Piperacillin-Tazobactam on Incidence of Acute Kidney Injury in Patients With Obesity

Background: Increasing evidence suggests that administration of combination vancomycin and piperacillin-tazobactam (VPT) increases the incidence of acute kidney injury (AKI) beyond that of vancomycin alone. But these investigations have not evaluated AKI risk specifically in an increasingly prevalent obese population in whom VPT pharmacokinetics are altered. Objective: To evaluate AKI risk with VPT administration to patients with obesity. Methods: We conducted a multicenter retrospective study of obese patients admitted to 2 separate academic teaching hospitals from January 2010 to December 2021, who received VPT, or vancomycin plus either cefepime, meropenem, or ceftazidime. The primary outcome evaluated AKI when patients were treated with or without VPT. Results: A total of 227 patients were evaluated (114 in VPT, vs 113 in control group). Overall, body mass index (35.6 kg/m2 ± 4.8vs 36.1 kg/m2 ± 5.2; P = .44) was similar between the VPT and control groups respectively. Total vancomycin dose on day 1 of antibiotic therapy (3,432 mg ± 935 vs 2,732 mg ± 912; P < .01) and nephrotoxin administration (75.4% vs 62.8%; P = .04) were higher in the VPT group. Incidence of AKI was higher in the VPT group (37.7%vs 14.2%; P = .01) and on regression analysis VPT was predictive of developing AKI (OR = 3.9; 95% CI = 2.0-7.7; P < .01). Conclusion and Relevance: In this retrospective study, the incidence of AKI was increased in obese patients receiving therapy with VPT. Vancomycin combination therapy with ceftazidime, cefepime, and meropenem appeared to be safe and was associated with less nephrotoxicity. Cautious use of VPT and further investigation with larger studies are warranted in this area.

Recombinant Klotho alleviates vancomycin-induced acute kidney injury by upregulating anti-oxidative capacity via JAK2/STAT3/GPx3 axis

Emerging studies support that Klotho protects against different kidney diseases. However, the role of Klotho in vancomycin induced acute kidney injury (Van-AKI) is largely unclear. Hence this study aimed to explore the regulatory mechanism of Klotho in Van-AKI. The mRNA expression of Klotho and the JAK2/STAT3/GPx3 in renal tissue were assessed by RNA sequence analysis after 600 mg/kg Van daily for seven days; Small interfering RNA and recombinant protein are applied to examine the mechanism action of Klotho in vitro and in vivo respectively. Flow cytometry and spectrophotometry detected the expression of reactive oxygen species and antioxidant enzymes. Transmission electron microscopy scanned the structural damage of mitochondria. Western blotting, qPCR, and immunofluorescence were employed to explore the JAK2/STAT3/GPx3 expression. RNA sequence analysis found that Van challenging reduced Klotho and GPx3 expression but increased JAK2/STAT3 in renal tissue. In HK-2 cells, Klotho were decreased by Van in a dose-dependent manner. Klotho siRNA enhanced the production of reactive oxygen species and the cell apoptosis ratio by regulating the JAK2/STAT3, and JAK2/STAT3 inhibitors prevented the decrease of GPx3. Meanwhile, 1 μg/ml recombinant human Klotho showed the opposite function to 120 pmol Klotho siRNA. In Van-AKI BALB/c mice, 20 μg/kg recombinant mouse Klotho once every two days improved the anti-oxidative enzyme expression, mitochondria structure, renal dysfunction, and histological damage. In conclusion, Klotho enhances antioxidant capacity through the JAK2/STAT3/GPx3 axis, which in turn improves Van-AKI.

Evaluation of Strategies for Reducing Vancomycin-Piperacillin/Tazobactam Incompatibility

BACKGROUND

Drug incompatibility is defined as a physical-chemical reaction between two or more injectable drugs and that results mainly in precipitation or insolubility. Several strategies for reducing incompatibilities have been implemented empirically in intensive care units. However, these strategies have never been compared directly (and particularly in terms of the particulate load and drug mass flow rate) under standardized conditions. The objective of the present in vitro study was to evaluate the impact of various strategies for preventing incompatibility between simultaneously infused vancomycin and piperacillin/tazobactam.

METHODS

An in-line filter, a dilute vancomycin solution (5 mg/mL), and an alternative saline administration line were evaluated separately. The infusion line outlet was connected to a dynamic particle counter. The antibiotic concentration was measured in an HPLC-UV assay.

RESULT

The use of an in-line filter and an alternative saline administration route did not significantly reduce the particulate load caused by vancomycin-piperacillin/tazobactam incompatibility. Dilution of the vancomycin solution was associated with a significantly lower particulate load and maintenance of the vancomycin mass flow rate.

DISCUSSION

It is important to systematically compare the efficacy of strategies for preventing drug incompatibility. The use of diluted vancomycin solution gave the best results in the case of vancomycin-piperacillin/tazobactam incompatibility.

Mechanisms of Piperacillin/Tazobactam Nephrotoxicity: Piperacillin/Tazobactam-Induced Direct Tubular Damage in Mice

Piperacillin/tazobactam (PT) is one of the most commonly prescribed antibiotics for critically ill patients in intensive care. PT has been reported to cause direct nephrotoxicity; however, the underlying mechanisms remain unknown. We investigated the mechanisms underlying PT nephrotoxicity using a mouse model. The kidneys and sera were collected 24 h after PT injection. Serum blood urea nitrogen (BUN), creatinine, neutrophil gelatinase-associated lipocalin (NGAL), and renal pathologies, including inflammation, oxidative stress, mitochondrial damage, and apoptosis, were examined. Serum BUN, creatinine, and NGAL levels significantly increased in PT-treated mice. We observed increased IGFBP7, KIM-1, and NGAL expression in kidney tubules. Markers of oxidative stress, including 8-OHdG and superoxide dismutase, also showed a significant increase, accompanied by mitochondrial damage and apoptosis. The decrease in the acyl-coA oxidase 2 and Bcl2/Bax ratio also supports that PT induces mitochondrial injury. An in vitro study using HK-2 cells also demonstrated mitochondrial membrane potential loss, indicating that PT induces mitochondrial damage. PT appears to exert direct nephrotoxicity, which is associated with oxidative stress and mitochondrial damage in the kidney tubular cells. Given that PT alone or in combination with vancomycin is the most commonly prescribed antibiotic in patients at high risk of acute kidney injury, caution should be exercised.

Nephrotoxicity of Vancomycin in Combination With Beta-Lactam Agents: Ceftolozane-Tazobactam vs Piperacillin-Tazobactam

BACKGROUND

Vancomycin (VAN)-associated acute kidney injury (AKI) is increased when VAN is combined with certain beta-lactams (BLs) such as piperacillin-tazobactam (TZP) but has not been evaluated with ceftolozane-tazobactam (C/T). Our aim was to investigate the AKI incidence of VAN in combination with C/T (VAN/C/T) compared with VAN in combination to TZP (VAN-TZP).

METHODS

We conducted a multicenter, observational, comparative study across the United States. The primary analysis was a composite outcome of AKI and risk, injury, failure, loss, end stage renal disease; Acute Kidney Injury Network; or VAN-induced nephrotoxicity according to the consensus guidelines. Multivariable logistic regression analysis was conducted to adjust for confounding variables and stratified Kaplan-Meir analysis to assess the time to nephrotoxicity between the 2 groups.

RESULTS

We included VAN/C/T (n = 90) and VAN-TZP (n = 284) at an enrollment ratio of 3:1. The primary outcome occurred in 12.2% vs 25.0% in the VAN-C/T and VAN-TZP groups, respectively (P = .011). After adjusting for confounding variables, VAN-TZP was associated with increased odds of AKI compared with VAN-C/T; with an adjusted odds ratio of 3.308 (95% confidence interval, 1.560-6.993). Results of the stratified Kaplan-Meir analysis with log-rank time-to-nephrotoxicity analysis indicate that time to AKI was significantly shorter among patients who received VAN-TZP (P = .004). Cox proportional hazards analysis demonstrated that TZP was consistent with the primary analysis (P = .001).

CONCLUSIONS

Collectively, our results suggest that the AKI is not likely to be related to tazobactam but rather to piperacillin, which is a component in VAN-TZP but not in VAN-C/T.

Risk Factors for Nephrotoxicity in Methicillin-Resistant Staphylococcus aureus Bacteraemia: A Post Hoc Analysis of the CAMERA2 Trial

BACKGROUND

Clinical risk factors for nephrotoxicity in Staphylococcus aureus bacteraemia remain largely undetermined, despite its common occurrence and clinical significance. In an international, multicentre, prospective clinical trial (CAMERA2), which compared standard therapy (vancomycin monotherapy) to combination therapy (adding an anti-staphylococcal beta-lactam) for methicillin-resistant S. aureus bacteraemia, significantly more people in the combination therapy arm experienced acute kidney injury compared with those in the monotherapy arm (23% vs 6%).

OBJECTIVE

The aim of this post hoc analysis was to explore in greater depth the risk factors for acute kidney injury from the CAMERA2 trial.

METHODS

Among participants of the CAMERA2 trial, demographic-related, infection-related and treatment-related risk factors were assessed for their relationship with acute kidney injury by univariable and multivariable logistic regression. Acute kidney injury was defined by a modified-KDIGO (Kidney Disease: Improving Global Outcomes) criteria (not including urinary output).

RESULTS

Of the 266 participants included, age (p = 0.04), randomisation to combination therapy (p = 0.002), vancomycin area under the concentration-time curve (p = 0.03) and receipt of (flu)cloxacillin as the companion beta-lactam (p < 0.001) were significantly associated with acute kidney injury. On a multivariable analysis, concurrent use of (flu)cloxacillin increased the risk of acute kidney injury over four times compared with the use of cefazolin or no beta-lactam. The association of vancomycin area under the concentration-time curve with acute kidney injury also persisted in the multivariable model.

CONCLUSIONS

For participants receiving vancomycin for S. aureus bacteraemia, use of (flu)cloxacillin and increased vancomycin area under the concentration-time curve were risk factors for acute kidney injury. These represent potentially modifiable risk factors for nephrotoxicity and highlight the importance of avoiding the use of concurrent nephrotoxins.

Comparative renal risk of long-term use of beta-lactams in combination with vancomycin across the continuum of care

Background

Data are controversial regarding nephrotoxicity risk with vancomycin plus piperacillin-tazobactam (VPT) compared to vancomycin alone or in combination with other beta-lactams (BLs) in acute care use. Furthermore, data are lacking on the incidence of acute kidney injury (AKI) with long-term use of VPT including outpatient parenteral antimicrobial therapy (OPAT).

Methods

This retrospective study included 826 adult patients on an intravenous vancomycin plus BL for ⩾2 weeks, including cefepime, piperacillin/tazobactam, ertapenem, or meropenem, from August 2017 to January 2022. The primary outcome was incidence of AKI. Univariate and multivariable Cox proportional hazard regression analyses were conducted to adjust for confounding variables. A secondary analysis based on the propensity score (PS)-matched cohort was performed.

Results

AKI occurred in 14.4% of patients in the VPT group (n = 15/104) compared to 5.5% in the other BL group (n = 40/722) (p < 0.001). Average time to AKI from start of combination therapy was 9.4 (1.7-12.0) days in the VPT group and 10.9 (5-22.7) days in the other BL group (p = 0.20). The median duration of vancomycin and BL in the overall cohort was approximately 1 month. Beyond BL selection, patient characteristics were not associated with AKI other than the receipt of concomitant acyclovir [hazard ratio (HR) 2.48 (95% confidence interval (CI): 1.33-4.65), p = 0.004]. In the PS-matched cohort, AKI occurred in 14.4% of patients in the VPT group (n = 15/104) and 5.3% in the other BL group (n = 11/208) (p = 0.006). Receipt of VPT [HR: 2.55 (1.36-4.78), p = 0.004] and acyclovir [HR: 2.38 (1.19-4.74), p = 0.014) remained significantly associated with AKI in the multivariable model.

Conclusion

Clinicians should exercise caution when using VPT for >2 weeks, including in the OPAT setting, even when no renal dysfunction is observed during the initial week of combination therapy.

Impact of a monthly antimicrobial stewardship quality assurance tool for elevated vancomycin levels

Objective:

We sought to determine the value of an audit-and-feedback monitoring method in facilitating meaningful practice changes to improve vancomycin dosing and monitoring.

Design:

Retrospective, multicenter, before-and-after implementation observational quality assurance initiative.

Setting:

The study was conducted in 7 not-for-profit, acute-care hospitals within a health system in southern Florida.

Methods:

The preimplementation period (September 1, 2019, through August 31, 2020) was compared to the postimplementation period (September 1, 2020, through May 31, 2022). All vancomycin serum-level results were screened for inclusion. The primary end point was the rate of fallout, defined as vancomycin serum level ≥25 µg/mL with acute kidney injury (AKI) and off-protocol dosing and monitoring. Secondary end points included the rate of fallout with respect to AKI severity, rate of vancomycin serum levels ≥25 µg/mL, and average number of serum-level evaluations per unique vancomycin patient.

Results:

In total, 27,611 vancomycin levels were analyzed from 13,910 unique patients. There were 2,209 vancomycin serum levels ≥25 µg/mL (8%) among 1,652 unique patients (11.9%). AKI was identified in 379 unique patients (23%) with a vancomycin levels ≥25 µg/mL. In total, 60 fallouts (35.2%) occurred in the 12-month preimplementation period (∼5 per month) and 41 fallouts (19.6%) occurred in the 21-month postimplementation period (∼2 per month; P = .0006). Failure was the most common AKI severity in both periods (risk: 35% vs 24.3%, P = .25; injury: 28.3% vs 19.5%, P = .30; failure: 36.7% vs 56%, P = .053). Overall, the number of evaluations of vancomycin serum levels per unique patient remained consistent throughout both periods (2 vs 2; P = .53).

Conclusions:

Implementation of a monthly quality assurance tool for elevated outlier vancomycin levels can improve dosing and monitoring practices resulting in enhanced patient safety.

Association of vancomycin plus piperacillin-tazobactam with early changes in creatinine versus cystatin C in critically ill adults: a prospective cohort study

PURPOSE

Although dozens of studies have associated vancomycin + piperacillin-tazobactam with increased acute kidney injury (AKI) risk, it is unclear whether the association represents true injury or a pseudotoxicity characterized by isolated effects on creatinine secretion. We tested this hypothesis by contrasting changes in creatinine concentration after antibiotic initiation with changes in cystatin C concentration, a kidney biomarker unaffected by tubular secretion.

METHODS

We included patients enrolled in the Molecular Epidemiology of SepsiS in the ICU (MESSI) prospective cohort who were treated for ≥ 48 h with vancomycin + piperacillin-tazobactam or vancomycin + cefepime. Kidney function biomarkers [creatinine, cystatin C, and blood urea nitrogen (BUN)] were measured before antibiotic treatment and at day two after initiation. Creatinine-defined AKI and dialysis were examined through day-14, and mortality through day-30. Inverse probability of treatment weighting was used to adjust for confounding. Multiple imputation was used to impute missing baseline covariates.

RESULTS

The study included 739 patients (vancomycin + piperacillin-tazobactam n = 297, vancomycin + cefepime n = 442), of whom 192 had cystatin C measurements. Vancomycin + piperacillin-tazobactam was associated with a higher percentage increase of creatinine at day-two 8.04% (95% CI 1.21, 15.34) and higher incidence of creatinine-defined AKI: rate ratio (RR) 1.34 (95% CI 1.01, 1.78). In contrast, vancomycin + piperacillin-tazobactam was not associated with change in alternative biomarkers: cystatin C: - 5.63% (95% CI - 18.19, 8.86); BUN: - 4.51% (95% CI - 12.83, 4.59); or clinical outcomes: dialysis: RR 0.63 (95% CI 0.31, 1.29); mortality: RR 1.05 (95%CI 0.79, 1.41).

CONCLUSIONS

Vancomycin + piperacillin-tazobactam was associated with creatinine-defined AKI, but not changes in alternative kidney biomarkers, dialysis, or mortality, supporting the hypothesis that vancomycin + piperacillin-tazobactam effects on creatinine represent pseudotoxicity.

Piperacillin–Tazobactam Plus Vancomycin-Associated Acute Kidney Injury in Adults: Can Teicoplanin or Other Antipseudomonal Beta-Lactams Be Remedies?

Numerous observational studies and meta-analyses have suggested that combination therapy consisting of piperacillin–tazobactam (TZP) and vancomycin (VAN) augments acute kidney injury (AKI) risk when compared to viable alternatives, such as cefepime–vancomycin (FEP–VAN) and meropenem–VAN. However, the exact pathophysiological mechanisms of this phenomenon are still unclear. One major limitation of the existing studies is the utilization of serum creatinine to quantify AKI since serum creatinine is not a sufficiently sensitive and specific biomarker to truly define the causal relationship between TZP–VAN exposure and nephrotoxicity. Even so, some preventive measures can be taken to reduce the risk of AKI when TZP–VAN is preferred. These measures include limiting the administration of TZP–VAN to 72 h, choosing FEP–VAN in place of TZP–VAN in appropriate cases, monitoring the VAN area under the curve level rather than the VAN trough level, avoiding exposure to other nephrotoxic agents, and minimizing the prescription of TZP–VAN for patients with a high risk of AKI. More data are needed to comment on the beneficial impact of the extended-infusion regimen of TZP on nephrotoxicity. Additionally, TZP and teicoplanin can be reasonable alternatives to TZP–VAN for the purpose of lowering AKI risk. However, the data are scarce to advocate this practice convincingly.

Evaluating the Safety of Trough Versus Area Under the Curve (AUC)-Based Dosing Method of Vancomycin With Concomitant Piperacillin-Tazobactam

Background: Vancomycin and piperacillin-tazobactam (VPT) is a common antibiotic combination used in hospitals, and there has been increasing data indicating that the combination is associated with increased rates of acute kidney injury (AKI). It is unclear if the dosing method of vancomycin would mitigate the risk of AKI seen with VPT. Objective: To observe and compare incidence of AKI in patients on VPT when using the trough-based dosing method versus the area-under-the-curve (AUC)-based dosing method. Methods: This was a multi-center, retrospective, observational study at 3 community hospitals. Adults receiving at least 48 hours of VPT were included. Patients with severe renal dysfunction, pregnant patients, prisoners, and patients with central nervous system infections, or malignancy were excluded. The primary outcome was incidence of AKI as defined by the Infectious Disease Society of America (IDSA) criteria. Results: A total of 300 patients were included in the study; 150 patients in both the trough and AUC groups. A total of 23 patients (15%) in the trough group and 17 patients (11%) in the AUC group met the primary outcome (odds ratio [OR]: 0.7058, 95% confidence interval [CI]: [0.3603, 1.3826], P = .3098). Conclusion and Relevance: The incidence of AKI was lower in the AUC group compared with the trough group; however, this was not significant. The results of our study suggest that there is no difference between incidence of AKI when using trough- or AUC-based dosing in those receiving VPT. Because of the small sample size and retrospective nature of the study, more data are needed.

Comparative Risk of Acute Kidney Injury Following Concurrent Administration of Vancomycin with Piperacillin/Tazobactam or Meropenem: A Systematic Review and Meta-Analysis of Observational Studies

The study aims to comparatively assess the nephrotoxicity of vancomycin when combined with piperacillin-tazobactam (V + PT) or meropenem (V + M) in adult patients hospitalized in general wards or intensive care units. We searched MEDLINE, Google Scholar, and Web of Science for observational studies evaluating incidences of AKI in adult patients receiving V + PT or V + M for at least 48 h in general wards or intensive care units. The primary outcome was AKI events, while the secondary outcomes were hospital length of stay, need for renal replacement therapy (RRT), and mortality events. The odds ratio (OR), or mean difference for the hospital length of stay, with a corresponding 95% confidence interval (CI) from the inverse variance weighting random-effects model were estimated for the risk of AKI, RRT, and mortality. Of the 112 studies identified, twelve observational studies were included in this meta-analysis with a total of 14,511 patients. The odds of having AKI were significantly higher in patients receiving V + PT compared with V + M (OR = 2.31; 95%CI 1.69–3.15). There were no differences between V + PT and V + M in the hospital length of stay, RRT, or mortality outcomes. Thus, clinicians should be vigilant while using V + PT, especially in patients who are at high risk of AKI.

Association of antibiotic use and acute kidney injury in patients hospitalized with community-acquired pneumonia

BACKGROUND

Acute kidney injury (AKI) is common among hospitalized patients with community-acquired pneumonia (CAP). We aimed to estimate and compare the risk of AKI for various antibiotic combinations in adults hospitalized for CAP.

METHODS

We conducted a retrospective cohort study of the Premier Healthcare Database containing all admissions for 660 US hospitals from 2010 to 2015. We included adults aged ≥18 years hospitalized with CAP and considered 6 different antibiotic combinations based on continuous use in the first 3 hospital days. The primary outcome was incident AKI, defined by ICD-9 codes 584.5-584-9. We evaluated associations of AKI with in-hospital mortality and length-of-stay. We excluded patients who were admitted directly to the intensive care unit, had AKI codes present on admission or had dialysis in the first 2 days. We used generalized linear mixed models with the hospital as a random effect and covariate adjustment for patient demographics, comorbidities, other treatments on day 0/1, and hospital characteristics.

RESULTS

The total sample included 449,535 patients, 3.15% of whom developed AKI. All other regimens but fluoroquinolones exhibited higher AKI odds than 3rd generation cephalosporin with or without macrolide. The combination of piperacillin/tazobactam and vancomycin with or without other antibiotics was associated with the highest AKI odds (OR = 1.89; 95% CI: 1.73-2.06). Patients with incident AKI had an increased odds of hospital mortality (OR = 6.37; 95% CI: 6.07-6.69) and longer length-of-stay (mean multiplier = 1.84; 95% CI: 1.82, 1.86).

CONCLUSION

Compared to 3rd generation cephalosporin with or without macrolide, piperacillin/tazobactam, vancomycin, and their combination were associated with higher odds of developing AKI, which in turn were associated with worse clinical outcomes.

Vancomycin-Associated Acute Kidney Injury: A Narrative Review from Pathophysiology to Clinical Application

Vancomycin is the most frequently used antibiotic, accounting for up to 35% of hospitalized patients with infection, because of its optimal bactericidal effectiveness and relatively low price. Vancomycin-associated AKI (VA-AKI) is a clinically relevant but not yet clearly understood entity in critically ill patients. The current review comprehensively summarizes the pathophysiological mechanisms of, biomarkers for, preventive strategies for, and some crucial issues with VA-AKI. The pathological manifestations of VA-AKI include acute tubular necrosis, acute tubulointerstitial nephritis (ATIN), and intratubular crystal obstruction. The proposed pathological mechanisms of VA-AKI include oxidative stress and allergic reactions induced by vancomycin and vancomycin-associated tubular casts. Concomitant administration with other nephrotoxic antibiotics, such as piperacillin–tazobactam, high vancomycin doses, and intermittent infusion strategies compared to the continuous infusion are associated with a higher risk of VA-AKI. Several biomarkers could be applied to predict and diagnose VA-AKI. To date, no promising therapy is available. Oral steroids could be considered for patients with ATIN, whereas hemodialysis might be applied to remove vancomycin from the patient. In the future, disclosing more promising biomarkers that could precisely identify populations susceptible to VA-AKI and detect VA-AKI occurrence early on, and developing pharmacological agents that could prevent or treat VA-AKI, are the keys to improve the prognoses of patients with severe infection who probably need vancomycin therapy.

Vancomycin Nephrotoxicity Causing Renal Transplant Acute Kidney Injury

Nephrotoxicity is a rather frequent side effect of vancomycin treatment. Attributes of vancomycin nephrotoxicity (VN) are well documented, including its clinical manifestations and renal morphologic changes. However, VN has not been emphasized as the cause of acute kidney injury (AKI) in the renal transplant setting. We report the first 3 such cases. In each of these cases, AKI developed concurrently with vancomycin treatment and resolved after its cessation. As compared with the general population, VN in the renal transplant setting displayed some unusual clinical behaviors. Its development was rather capricious, being noted in some but not every episode of vancomycin treatment, even in the same individual. AKI developed gradually in conjunction with protracted vancomycin treatment, in contrast to a precipitous course in the nontransplant setting. However, renal transplant biopsies showed typical features of VN in each case. VN is an unusual but now well-documented cause of AKI in renal transplant recipients. VN in this setting may display some atypical features, setting it apart from that in the general population. However, renal transplant biopsy changes are characteristic and are amenable to a definitive diagnosis.

Impact of Area Under the Concentration-Time Curve on the Prevalence of Vancomycin-Induced Nephrotoxicity in Combination With Tazobactam/Piperacillin or Cefepime: A Single-Institution Retrospective Study

PURPOSE

Risk for vancomycin-induced nephrotoxicity (VIN) is reportedly reduced by AUC-guided vancomycin dosing. However, it remains unknown whether the increased VIN risk in combination treatment with vancomycin and tazobactam/piperacillin, which is a VIN risk factor, can be diminished by AUC-guided vancomycin dosing (vancomycin-AUC). The aim of this study was to assess whether the evaluation of vancomycin-AUC + tazobactam/piperacillin (VT) combination therapy could prevent VIN.

METHODS

The data from patients who received VT or vancomycin + cefepime (VC; the control group) at Tokushima University Hospital (Kuramoto, Japan) between April 2010 and March 2020 were analyzed in this retrospective study. The between-group difference in the prevalence of VIN onset, stratified by AUC, was investigated. The AUC of vancomycin was calculated using the Bayesian method with the blood concentration of vancomycin. The risk factors and probability of VIN onset from the vancomycin exposure-toxicity curve were evaluated using the logistic model.

FINDINGS

The prevalences of VIN were 29.5% (18/61) and 7.1% (3/42) in the VT and VC groups, respectively. Multivariate logistic regression analysis of data from all patients revealed concurrent use of tazobactam/piperacillin (odds ratio [OR] = 4.59; P = 0.039) and AUC increase (OR = 1.01; P < 0.01) as risk factors for VIN, but only concurrent use of tazobactam/piperacillin was identified as a risk factor in patients with an AUC of <600 μg · h/mL, the guideline-recommended value (OR = 9.52; P = 0.041). Moreover, the vancomycin exposure-toxicity curve showed that in the guideline-recommended AUC range, VIN probability was consistently higher and the slope of VIN probability was greater in the VT group than in the VC group.

IMPLICATIONS

VIN risk was higher with VT than with VC, even when the AUC was controlled to the guideline-recommended range. These results strongly suggest that VIN prevention may be difficult with AUC-guided vancomycin dosing in patients receiving VT.

Select controversies in the management of methicillin-resistant Staphylococcus aureus bacteremia: answers and remaining questions from recent evidence

Methicillin-resistant Staphylococcus aureus (MRSA) bacteremia continues to cause significant morbidity and mortality despite advances in medical therapy. Vancomycin therapy remains the standard of care for most cases of MRSA bacteremia but has pharmacokinetic and pharmacodynamic limitations, dosing complications, and known toxicity. Welcomed clinical trials have recently addressed some of the controversies that plague this field, including optimization of vancomycin dosing and use of combination therapy. In this review, we discuss these trials and their implications for clinical care and future research.

Dealing with MDR bacteria and biofilm in the post-antibiotic era: Application of antimicrobial peptides-based nano-formulation

The rapid development of multidrug-resistant (MDR) bacteria due to the improper and overuse of antibiotics and the ineffective performance of antibiotics against the difficult-to-treat biofilm-related infections (BRIs) have urgently called for alternative antimicrobial agents and strategies in combating bacterial infections. Antimicrobial peptides (AMPs), owing to their compelling antimicrobial activity against MDR bacteria and BRIs without causing bacteria resistance, have attracted extensive attention in the research field. With the development of nanomaterial-based drug delivery strategies, AMPs-based nano-formulations have significantly improved the therapeutic effects of AMPs by ameliorating their hydrolytic stability, half-life in vivo, and solubility as well as reducing the cytotoxicity and hemolysis, etc. This review has comprehensively summarized the application AMPs-based nano-formulation in various bacterial infections models, including bloodstream infections (specifically sepsis), pulmonary infections, chronic wound infections, gastrointestinal infections, among others. The design of the nanomaterial-based drug delivery systems and the therapeutic effects of the AMPs-based nano-formulations in literature have been categorized and in details discussed. Overall, this review provides insights into the advantages and disadvantages of the current developed AMPs-based nano-formulations in literature for the treatment of bacterial infections, bringing inspirations and suggestions for their future design in the way towards clinical translation.

Comparison between early surgical treatment and conservative treatment of appendicitis in cancer patients

BACKGROUNDS

In cancer patients, the optimal appendicitis treatment has not been established. Therefore, we aimed to determine the ideal treatment option for appendicitis in cancer patients.

METHODS

This retrospective study included 185 cancer patients with acute appendicitis who were divided into the early surgical group (n = 152) involving surgery performed within 48 h following the appendicitis diagnosis or the conservative group (n = 33) involving intravenous antibiotics. We compared the appendicitis treatment efficacy between the groups.

RESULTS

In the early surgical group, the antibiotic duration [5.5 days (4.0-8.0) vs. 17.0 days (12.5-25.0), p < 0.001] and hospital stay length [7.0 days (5.0-11.75) vs. 10.0 days (8.0-32.0), p < 0.001] were significantly shorter. Regarding pathology, 16/171 (9.4%) patients who underwent surgery exhibited appendiceal tumours. During the 1-year follow-up period, one recurrence occurred in each group [1/152 (0.7%) vs. 1/33 (3.0%), p = 0.326]. The 1-year treatment success rate was higher in the early surgical group [99.3% (151/152) vs. 42.4% (14/33), p < 0.001].

CONCLUSION

Early surgical treatment yielded a significantly higher success rate than conservative treatment for appendicitis in cancer patients. Surgery for appendicitis in cancer patients should be considered not only for treatment but also for pathologic confirmation.

Intravenous magnesium sulfate for prevention of vancomycin plus piperacillin-tazobactam induced acute kidney injury in critically ill patients: An open-label, placebo-controlled, randomized clinical trial

BACKGROUND

Recent studies have shown an increased risk of acute kidney injury (AKI) induced by vancomycin + piperacillin-tazobactam (VPT) combination. In this study, the efficacy of intravenous magnesium sulfate in prevention of VPT induced AKI in critically ill patients admitted to the ICU has been evaluated.

METHODS

In an open-label, placebo-controlled, randomized clinical trial, 72 adults (≥ 18 years old) who had indications to receive VPT as empiric therapy were assigned to the magnesium or control group in 1:1 ratio. Concomitant with VPT, intravenous infusion of magnesium sulfate was started for patients in the magnesium group. The target serum level of magnesium was defined 3 mg/dl. Patients in the control group received normal saline as placebo. The target serum level of magnesium was defined 1.9 mg/dl in this group. The study's primary outcome was incidence of AKI during and up to 48 h after the treatment course. Escalation and de-escalation of VPT regimen, duration of hospitalization, length of ICU stay and 28-day mortality were secondary outcomes.

RESULTS

Thirty patients in each group completed the examination. Five patients in the magnesium group and 11 patients in the control group experienced AKI (p = 0.072). De-escalation of VPT regimen was done approximately in 60% of patients. Duration of hospitalization and length of ICU stay were not statistically different between the groups. Finally, 28-day mortality was 23.33% in each group. Although the incidence of AKI was not statistically different between the groups in unadjusted logistic regression model, it became significant after adjusting for confounding factors [unadjusted model (OR = 0.34; 95% CI: 0.10-1.16, p = 0.084), adjusted model: (OR = 0.26; 95% CI: 0.07-0.96, p = 0.04)].

CONCLUSIONS

Administration of magnesium sulfate with the target serum levels around 3 mg/dL reduced the incidence of AKI in critically ill patients who were receiving VPT as empric therapy.

Evaluating and Mitigating Risk of Acute Kidney Injury with the Combination of Vancomycin and Piperacillin-Tazobactam in Children

The antibiotic combination of vancomycin (VAN) and piperacillin-tazobactam (PTZ) has been associated with an increased risk of acute kidney injury (AKI) in both adult and pediatric patients. In this review, we highlight some of the limitations of existing pediatric studies evaluating the combination of VAN/PTZ, focusing on AKI risk in specific pediatric patient populations. We also review the variability in defining AKI in children and provide guidance to clinicians for use of prospective surveillance and stewardship in mitigating the risk of AKI in pediatric patients treated with combination of VAN/PTZ. Based on review of available pediatric studies, if the combination of VAN/PTZ is selected as an empirical antibiotic combination, it should be used in those at low risk for AKI and should be used with extreme caution in patients with additional nephrotoxic risks. Systems should be in place to monitor the use of VAN/PTZ and associated renal function in those receiving this antibiotic combination.

Lack of synergistic nephrotoxicity between vancomycin and piperacillin/tazobactam in a rat model and a confirmatory cellular model

BACKGROUND

Vancomycin and piperacillin/tazobactam are reported in clinical studies to increase acute kidney injury (AKI). However, no clinical study has demonstrated synergistic toxicity, only that serum creatinine increases.

OBJECTIVES

To clarify the potential for synergistic toxicity between vancomycin, piperacillin/tazobactam and vancomycin + piperacillin/tazobactam treatments by quantifying kidney injury in a translational rat model of AKI and using cell studies.

METHODS

(i) Male Sprague-Dawley rats (n = 32) received saline, vancomycin 150 mg/kg/day intravenously, piperacillin/tazobactam 1400 mg/kg/day intraperitoneally or vancomycin + piperacillin/tazobactam for 3 days. Urinary biomarkers and histopathology were analysed. (ii) Cellular injury was assessed in NRK-52E cells using alamarBlue®.

RESULTS

Urinary output increased from Day -1 to Day 1 with vancomycin but only after Day 2 for vancomycin + piperacillin/tazobactam-treated rats. Plasma creatinine was elevated from baseline with vancomycin by Day 2 and only by Day 4 for vancomycin + piperacillin/tazobactam. Urinary KIM-1 and clusterin were increased with vancomycin from Day 1 versus controls (P < 0.001) and only on Day 3 with vancomycin + piperacillin/tazobactam (P < 0.001, KIM-1; P < 0.05, clusterin). The histopathology injury score was elevated only in the vancomycin group when compared with piperacillin/tazobactam as a control (P = 0.04) and generally not so with vancomycin + piperacillin/tazobactam. In NRK-52E cells, vancomycin induced cell death with high doses (IC50 48.76 mg/mL) but piperacillin/tazobactam did not, and vancomycin + piperacillin/tazobactam was similar to vancomycin.

CONCLUSIONS

All groups treated with vancomycin demonstrated AKI; however, vancomycin + piperacillin/tazobactam was not worse than vancomycin. Histopathology suggested that piperacillin/tazobactam did not worsen vancomycin-induced AKI and may even be protective.

Eosinophilic pneumonia caused by cefepime: A case report and review

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Eosinophilic pneumonia (EP) is a diagnosis supported by increased blood eosinophils & infiltrates on chest radiographs.

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We highlight the first known case of EP caused by cefepime in a patient treated for pneumonia.

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Cefepime is commonly used for a variety of infections in hospitals and EP may be an underreported adverse event.

Eosinophilic pneumonia (EP) is characterized by accumulation of eosinophils in the lungs and has been associated with several medications, including antimicrobials. Cefepime is a commonly used broad-spectrum antimicrobial agent for the treatment of nosocomial infections but to date has not been associated with EP. We report the first documented case of EP secondary to cefepime for the treatment of pneumonia. The patient’s peripheral eosinophilia and leukocytosis resolved promptly after discontinuation of cefepime and initiation of steroid treatment.

Current Paradigms of Combination therapy in Methicillin-Resistant Staphylococcus aureus (MRSA) Bacteremia: Does it Work, Which Combination and For Which Patients?

The last several years have seen an emergence of literature documenting the utility of combination antimicrobial therapy, particularly in the salvage of refractory MRSA bacteremia. Recent clinical data are shaping conundrums of which regimens may be more beneficial, which can be potentially harmful, and which subset of patients stand to benefit from more aggressive treatment regimens than called for by current standards. In addition, the incorporation of combination therapy for MRSA bacteremia should be accompanied by the reminder that antimicrobial therapy does not need to be uniform for the entire duration, with an early intensive phase in high inoculum infections (e.g. with combination therapy), followed by a consolidation phase (i.e. monotherapy). This review and perspective consolidates the recent data on this subject and directs future goals in filling the knowledge gaps to methodically move forward towards improving patient outcomes.

Development of the Three Antimicrobial Stewardship E's (TASE) framework and Association between Stewardship Interventions and intended Results (ASIR) analysis to identify key facility-specific interventions and strategies for successful antimicrobial stewardship

BACKGROUND

Successful antimicrobial stewardship (AS) interventions have been described previously. Currently, a uniform operational approach to planning and implementing successful AS interventions does not exist. From 2015 to 2019, concomitant vancomycin and piperacillin-tazobactam use (CVPTU) for >48 hours at Vanderbilt University Medical Center (VUMC) significantly decreased through AS efforts. We analyzed the interventions that led to this change and created a model to inform future intervention planning and development.

METHODS

VUMC adult admissions from January 2015 to August 2019 were evaluated for CVPTU. Percentage of admissions receiving CVPTU >48 hours, the primary outcome, was evaluated using statistical process control charts. We created the Three Antimicrobial Stewardship E's (TASE) framework and Association between Stewardship Interventions and intended Results (ASIR) analysis to assess potential intensity and impact of interventions associated with successful change during this time period and to identify guiding principles for development of future initiatives.

RESULTS

The mean percentage of admissions receiving CVPTU per month declined from 4.2% to 0.7%. Over 8 time periods, we identified 4 high, 3 moderate and 1 low intervention intensity periods. Continuous provider-level AS education was present throughout. Creation and dissemination of division and department algorithms and reinforcement via computerized provider order entry sets preceded the largest reduction in CVPTU and sustained prescribing practice changes.

CONCLUSIONS

The TASE framework and ASIR analysis successfully identified pivotal interventions and strategies needed to effect and sustain change at VUMC. Further research is needed to validate its effectiveness as a stewardship intervention planning tool at our institution and others.

Vancomycin-Associated Tubular Casts and Vancomycin Nephrotoxicity

Introduction

Vancomycin nephrotoxicity is frequent and may be due to drug-induced acute tubular necrosis (ATN) or tubulointerstitial nephritis (TIN). Vancomycin-associated tubular cast (VTC) was recently described and may represent a novel cause of vancomycin nephrotoxicity. However, much is still unknown about VTC.

Materials and Methods

Thirty-seven kidney biopsy specimens from patients who were treated with vancomycin and developed acute kidney injury (AKI) were found among a total of 4673 biopsy samples between 2010 and 2019. These biopsy specimens were subjected to light microscopy, immunofluorescence, electron microscopy, and immunolocalization for vancomycin, uromodulin, myoglobin, tubular segment–specific markers, and examined for VTCs. The findings were correlated with the clinical course.

Results

VTCs displayed precipitated vancomycin casts in a background of uromodulin; the casts were limited to the distal tubules, and always associated with a background of more diffuse renal injury (ATN or TIN). The diagnosis of vancomycin nephrotoxicity was made in in 28 of 37 patients. VTC was noted in 25 of 28 biopsy samples from patients diagnosed with vancomycin nephrotoxicity and in one of nine biopsy samples from patients without this diagnosis. Vancomycin nephrotoxicity was diagnosed in 25 of 26 patients whose biopsy specimens showed VTC, but in only 3 of 11 patients without VTC in the biopsy samples.

Conclusions

VTC displays a characteristic morphologic profile amenable to ready recognition in biopsy specimens. It results from coprecipitation of vancomycin and uromodulin. It facilitates the biopsy diagnosis of vancomycin nephrotoxicity. It may have a nephrotoxic effect superimposing on and independent from the ATN or interstitial nephritis in the pathogenesis of vancomycin nephrotoxicity.

Cefepime use: A need for antimicrobial stewardship

OBJECTIVES

Unlike other 3GCs, Cefepime is a cephalosporin that has, in animal model studies, shown a low risk of selecting resistant mutants. It also enables carbapenems to be saved in treatment of Pseudomonasaeruginosa and the CESP group (Citrobacter, Enterobacter, Serratia and Providencia, as well as the genus Klebsiellaaerogenes, Morganella and Hafnia), consequently producing cephalosporinase. We aimed to determine whether its prescription in a French teaching hospital met criteria for proper use.

PATIENTS AND METHODS

We conducted a retrospective study of proper cefepime use between March 1st, 2018 and February 28th, 2019, to assess indication, antimicrobial stewardship, dosing schedule, microbiological documentation, reevaluation, and treatment duration. Prescriptions were then compared to local guidelines established from international literature.

RESULTS

Out of 142 cefepime prescriptions, 97.2% were prescribed as validated according to indication. The duration of the documented treatments matched the guidelines for 56.5% of patients, dosage was adapted to the indication for 77.4% and to kidney function for 97.2%. Bacteriological documentation was performed in all cases and an antibiogram was generated in 99.2% of cases. The treatment was reassessed between 48 and 72h and between the 7th and 10th day for 44.2% and 60.9% of the prescriptions respectively. The antimicrobial stewardship team managed half of the prescriptions. Only 13.4% of prescriptions met all criteria for proper use.

CONCLUSION

Notwithstanding a highly sizable majority of validated indications, a very small proportion of cefepime prescriptions met all the criteria for proper use. In the context of increased cefepime consumption, which is favored by its increased place in the latest recommendations published in 2019, proper use of cefepime prescriptions needs to be more effectively promoted.

Baseline kidney function is associated with vancomycin-induced acute kidney injury in children: a prospective nested case-control study

BACKGROUND

Children with kidney insufficiency are susceptible to vancomycin-induced acute kidney injury (VIAKI), but there is a lack of compelling clinical data. We conducted a nested case-control study to evaluate the relationship between kidney insufficiency and incidence of VIAKI in children.

METHODS

Patients were considered to have VIAKI if they met the criteria for eGFR change according to pRIFLE-I or p-RIFLE-F. Case group comprised patients who developed VIAKI. Case-control ratio was 1:3; patients were matched for age, severity, and nature of illness and initial vancomycin dose. Primary endpoint was incidence of VIAKI at three levels of kidney function, calculated using Kaplan-Meier curve and log-rank test. Secondary endpoint was treatment-related in-hospital mortality amongst case and control groups.

RESULTS

Amongst 386 children who fit study criteria, 31 developed VIAKI (8.03%). Thirty-one cases and 93 controls were selected from the observed cohort. Three risk factors were identified for VIAKI: moderate kidney insufficiency (OR 8.8, 2.4-32.8), vancomycin trough concentration ≥ 15 μg/mL (OR 7.7, 1.7-34.4), and furosemide use (OR 24.8, 6.4-98.2). A significant difference in time to VIAKI was noted between patients with moderate kidney insufficiency and patients with mild kidney insufficiency or normal kidney function (p < 0.001). In-hospital mortality rate in case group was 45.2%, compared to 18.3% in control group (p < 0.01).

CONCLUSIONS

Children with moderate kidney insufficiency are more likely to develop VIAKI than those with normal and mild kidney insufficiency. Patients who develop VIAKI have higher in-hospital mortality than those who do not develop VIAKI.

Combination of vancomycin plus piperacillin and risk of acute kidney injury: a worldwide pharmacovigilance database analysis

BACKGROUND

Excess of acute kidney injury (AKI) secondary to the association of vancomycin plus piperacillin is debated.

OBJECTIVES

To detect a signal for an increased risk of AKI with the vancomycin and piperacillin combination compared with other vancomycin-based regimens.

METHODS

Using VigiBase, the WHO global database of individual case safety reports (ICSR) from 1997 to 2019, we conducted a disproportionality analysis comparing the reporting of AKI cases between different vancomycin-based regimens (vancomycin plus piperacillin, cefepime or meropenem). To take into account a possible notoriety bias, we secondarily restricted the study period to before 2014, the date of the first publication of AKI in patients receiving vancomycin plus piperacillin. Results are expressed using the reporting OR (ROR) and its 95% CI.

RESULTS

From 1997 to 2019, 53 701 ICSR concerning vancomycin have been registered in the database, including 6016 reports of AKI (11.2%), among which 925 (15.4%) were reported with vancomycin/piperacillin, 339 (5.6%) with vancomycin/cefepime and 197 (3.7%) with vancomycin/meropenem. ROR (95% CI) for AKI was 2.6 (2.4-2.8) for vancomycin/piperacillin, 2.5 (2.2-2.9) for vancomycin/cefepime and 0.5 (0.4-0.6) for vancomycin/meropenem versus other vancomycin-containing regimens. After restriction of the study period to 1997-2013, the ROR for AKI remains significant only for vancomycin/piperacillin [ROR (95% CI) = 2.1 (1.8-2.4)].

CONCLUSIONS

We found a disproportionality in reports of AKI in patients receiving vancomycin plus piperacillin compared with vancomycin in other regimens. This suggests a drug-drug interaction between these two antibiotics resulting in an increased risk of AKI.

Alteration in Acute Kidney Injury Potential with the Combination of Vancomycin and Imipenem-Cilastatin/Relebactam or Piperacillin/Tazobactam in a Preclinical Model

The risk of vancomycin (VAN)-associated acute kidney injury (AKI) may be altered with combination regimens. The specific AKI risk when VAN is combined with imipenem-cilastatin/relebactam (IMP-C/REL) or piperacillin/tazobactam (TZP) has not been clearly defined. We sought to quantify the dose-AKI relationships of VAN alone and in combination with TZP or IMP-C/REL. Male C57BL/6J mice (Charles River Laboratory) aged 10 to 12 weeks were dosed with study drug regimens in three stages. Stage 1 consisted of a VAN dose-ranging design (0 to 600 mg/kg daily) over a 7-day period to identify the VAN monotherapy dose-AKI relationship in the murine model. Stage 2 evaluated the approximate VAN dose eliciting 50% AKI response in stage 1 in combination with the highest human equivalent doses (HEDs) used in preclinical murine models (2.5 and 320 mg/kg daily for TZP and IMP-C/REL, respectively). Stage 3 tested these combinations with fractionated doses of TZP or IMP-C/REL administered at 6- and 12-h intervals. In these studies, AKI was defined with biomarkers (serum creatinine [SCr], blood urea nitrogen [BUN]) and with histopathological assessment by a treatment-blinded pathologist. VAN doses of 300 to 500 mg/kg daily reproducibly led to development of AKI within 4 days of dosing. Mice treated with VAN alone had a near doubling of their baseline SCr and BUN levels compared with mice treated with control, IMP-C/REL alone, or TZP alone. Both VAN+IMP-C/REL and VAN+TZP had significantly (P < 0.05) lower SCr and BUN values than VAN alone when dosed once daily. This nephroprotective effect was retained with VAN+IMP-C/REL but not VAN+TZP when IMP-C/REL and TZP were administered every 6 h. Biomarker results were concordant with histopathological findings. The VAN dose-AKI relationship can be attenuated with single daily HEDs of TZP or IMP-C/REL in mice. IMP-C/REL, but not TZP, retained a nephroprotective effect compared with VAN monotherapy when administered as fractionated doses.

Evaluation of area under the concentration-time curve-guided vancomycin dosing with or without piperacillin-tazobactam on the incidence of acute kidney injury

OBJECTIVES

Recent studies suggest that the combination of piperacillin-tazobactam (P-T) and vancomycin increases the risk for acute kidney injury (AKI). The purpose of this study was to determine if area under the concentration-time curve (AUC)-guided vancomycin dosing reduced the incidence of AKI in a sample of patients who also received P-T.

METHODS

This single-centre, retrospective, pre-post quasi-experimental study compared the incidence of AKI before and after a health-system-wide change from trough- to AUC-guided vancomycin dosing using two post-distribution levels. The primary outcome was AKI, defined as an increase in serum creatinine ≥0.5 mg/dL or 50% from baseline for two consecutive measurements, in patients who received vancomycin with or without concomitant P-T.

RESULTS

In total, 636 patients were included in this study (308 trough-guided, 328 AUC-guided); of these, 118 patients in each group received concomitant P-T. The primary outcome occurred in 35 (11.4%) patients in the trough-guided group and 24 (7.3%) patients in the AUC-guided group (P=0.105). There was no difference in the incidence of AKI in the population receiving concomitant P-T between dosing strategies. The incidence of AKI was significantly higher in patients who received concomitant P-T compared with patients who did not receive concomitant P-T in both the trough-guided group [21/118 (17.8%) versus 14/190 (7.4%), respectively; P=0.003] and the AUC-guided group [16/118 (13.6%) versus 8/210 (3.8%), respectively; P=0.0011].

CONCLUSIONS

The incidence of AKI did not differ significantly between trough- and AUC-guided vancomycin dosing. Caution should be taken when combining vancomycin and P-T regardless of dosing strategy. Larger studies are needed to confirm these findings.

Risk of Acute Kidney Injury in Combat-Injured Patients Associated With Concomitant Vancomycin and Extended-Spectrum β-Lactam Antibiotic Use

BACKGROUND

Multidrug-resistant infections complicating combat-related trauma necessitate the use of broad-spectrum antimicrobials. Recent literature posits an association between vancomycin (VANC) and piperacillin-tazobactam (VPT) combination therapy and acute kidney injury (AKI). We examined whether therapy with VPT was associated with an increased risk of AKI compared to VANC and other broad-spectrum β-lactam antibiotics (VBL) following combat-related injuries.

METHODS

Patients within the Trauma Infectious Disease Outcomes Study (TIDOS) who received ≥48 hours concomitant VPT or VBL started within 24 hours of each other were assessed. Exclusion criteria were receipt of renal replacement therapy and baseline creatinine >1.5 mg/dL. Acute kidney injury was defined by meeting any of the Risk, Injury, Failure, Loss, End Stage Renal Disease (RIFLE), AKIN, or VANC consensus guidelines criteria 3 to 7 days after therapy initiation. Variables significantly associated with AKI were used in inverse probability treatment weighting to perform univariate and subsequent logistic regression multivariate modeling to determine significant risk factors for AKI.

RESULTS

Sixty-one patients who received VPT and 207 who received VBL were included. Both groups had a median age of 24 years and initial median creatinine of 0.7 mg/dL. The VBL patients were more likely to have sustained blast injuries (P = .001) and received nephrotoxic agents (amphotericin [P = .002] and aminoglycosides [P < .001]). In the VBL group, AKI incidence was 9.7% compared to 13.1% in the VPT group (P = .438). Multivariate analysis identified a relative risk of 1.727 (95% CI: 1.027-2.765) for AKI associated with VPT exposure. Acute kidney injury severity generally met RIFLE Risk criteria and was 1 day in duration. Only 1 patient had persistent renal dysfunction 30 days after therapy completion.

CONCLUSION

In this young and previously healthy, severely ill combat-injured population, VPT was associated with nearly twice the risk of AKI compared to VBL. Nevertheless, AKI was of low severity, short duration, and had high rates of renal recovery.

[Combinatorial Vancomycin and Piperacillin/Tazobactam Results in Elevated Vancomycin Trough Concentration and Acute Kidney Injury: A Case Report]

In the hospital, antibiotics are widely used to treat infections. We report a case of acute kidney injury (AKI) caused by an antibiotic drug combination. A 30-year-old Japanese male presented with lung metastases, pneumothorax, empyema, and methicillin-resistant Staphylococcus aureus (MRSA) infection. The patient received a combination of vancomycin and piperacillin/tazobactam, which resulted in elevated vancomycin trough concentration and subsequently in AKI. Renal function was restored upon vancomycin and piperacillin/tazobactam cessation. Though this patient had AKI most likely due to the combined use of two agents as has been reported in many cases, vancomycin trough concentration showed an unexpected abnormal increase when halting vancomycin treatment. This is the first report indicating a drug-drug interaction between vancomycin and piperacillin/tazobactam with unexpected abnormal vancomycin trough concentration, leading to AKI, additionally we think that there was a situation that he stressed against the kidney by a history of medications caused renal dysfunction and co-administration. We suggest that when using vancomycin in combination with piperacillin/tazobactam, the trough concentration of vancomycin must be confirmed simultaneously with renal function and evaluation, and that the combination of these two drugs should be minimized.

Acute kidney injury following the concurrent administration of antipseudomonal β-lactams and vancomycin: a network meta-analysis

BACKGROUND

Acute kidney injury is a major complication of vancomycin treatment, especially when it is co-administered with other nephrotoxins.

OBJECTIVES

This meta-analysis aims to comparatively assess the nephrotoxicity of antipseudomonal β-lactams when combined with vancomycin.

DATA SOURCES

Medline, Scopus, CENTRAL and Clinicaltrials.gov databases were systematically searched from inception through 20 August 2019.

STUDY ELIGIBILITY CRITERIA

Studies evaluating acute kidney injury risk following the concurrent use of antipseudomonal β-lactams and vancomycin were selected.

PARTICIPANTS

Adult and paediatric patients treated in hospital or intensive care unit.

INTERVENTIONS

Administration of vancomycin combined with any antipseudomonal β-lactam.

METHODS

Acute kidney injury incidence was defined as the primary outcome. Secondary outcomes included severity, onset, duration, need of renal replacement therapy, length of hospitalization and mortality. Quality of evidence was assessed using the ROBINS-I tool and the Confidence In Network Meta-Analysis approach.

RESULTS

Forty-seven cohort studies were included, with a total of 56 984 patients. In the adult population, the combination of piperacillin-tazobactam and vancomycin resulted in significantly higher nephrotoxicity rates than vancomycin monotherapy (odds ratio (OR) 2.05, 95% confidence intervals (CI) 1.17-3.46) and its concurrent use with meropenem (OR 1.84, 95% CI 1.02-3.10) or cefepime (OR 1.80, 95% CI 1.13-2.77). In paediatric patients, acute kidney injury was significantly higher with vancomycin plus piperacillin-tazobactam than vancomycin alone (OR 4.18, 95% CI 1.01-17.29) or vancomycin plus cefepime OR 3.71, 95% CI 1.08-11.24). No significant differences were estimated for the secondary outcomes. Credibility of outcomes was judged as moderate, mainly due to imprecision and inter-study heterogeneity.

CONCLUSIONS

The combination of vancomycin and piperacillin-tazobactam is associated with higher acute kidney injury rates than its parallel use with meropenem or cefepime. Current evidence is exclusively observational and is limited by inter-study heterogeneity. Randomized controlled trials are needed to verify these results and define preventive strategies to minimize nephrotoxicity risk.

Development and Validation of a Risk Prediction Model of Vancomycin-Associated Nephrotoxicity in Elderly Patients: A Pilot Study

This exploratory study aimed to develop a risk prediction model of vancomycin‐associated nephrotoxicity (VANT) in elderly patients. Clinical information of elderly patients who received vancomycin therapy from January 2016 to June 2018 was retrieved. A total of 255 patients were included in this study. Univariate analysis and multivariable logistic regression analysis revealed that vancomycin trough concentration ≥ 20 mg/L (odds ratio (OR) = 3.009; 95% confidence interval (CI) 1.345–6.732), surgery (OR = 3.357; 95% CI 1.309–8.605), the Charlson Comorbidities Index ≥ 4 points (OR = 2.604; 95% CI 1.172–5.787), concomitant use of cardiotonic drug (OR = 3.283; 95% CI 1.340–8.042), plasma volume expander (OR = 3.459; 95% CI 1.428–8.382), and piperacillin/tazobactam (OR = 2.547; 95% CI 1.680–6.007) were risk factors for VANT in elderly patients. Furthermore, a VANT risk prediction model was developed, which had good discriminative power and was well‐calibrated.

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.

Effect of serum concentration and concomitant drugs on vancomycin-induced acute kidney injury in haematologic patients: a single-centre retrospective study

PURPOSE

Appropriate use of vancomycin (VCM) is important in preventing acute kidney injury (AKI). Because of the high frequency of VCM use for febrile neutropenia and concomitant use of other nephrotoxic drugs, haematologic patients have a different nephrotoxic background compared with patients with other diseases. Therefore, it is unclear whether the risk factors of VCM-induced AKI identified in other patient groups are also applicable to haematologic patients. Herein, we performed a single-centre retrospective analysis to identify the factors associated with VCM-induced AKI in haematologic patients.

METHODS

We retrospectively analysed 150 haematologic patients to whom VCM was administered between April 2010 and March 2018 at Tokushima University Hospital. VCM-induced AKI was defined according to Kidney Disease Improving Global Outcomes (KDIGO) criteria. Multivariate logistic regression analyses were performed to identify risk factors for VCM-induced AKI.

RESULTS

Seventeen patients had VCM-induced AKI. Multivariate analysis revealed that the risk factors of VCM-induced AKI were an initial VCM trough concentration of > 15 mg/L and concomitant use of tazobactam/piperacillin (TAZ/PIPC) and liposomal amphotericin B (L-AMB). Patients with an initial VCM trough concentration of < 10 mg/L showed significantly lower efficacy in febrile neutropenia. Interestingly, concomitant L-AMB use increased the incidence of VCM-induced AKI in a VCM concentration-dependent manner, whereas concomitant TAZ/PIPC increased the incidence in a VCM concentration-independent manner.

CONCLUSIONS

The optimal initial VCM trough concentration was 10-15 mg/L in haematologic patients, considering safety and effectiveness. There were differences in the effect of VCM-induced AKI between nephrotoxic drugs.

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.

The Risk of Acute Kidney Injury in Critically Ill Patients Receiving Concomitant Vancomycin With Piperacillin-Tazobactam or Cefepime

PURPOSE

The objective of this study was to compare the incidence of acute kidney injury (AKI) among critically ill patients receiving combination therapy with vancomycin plus piperacillin-tazobactam (VPT) against patients receiving vancomycin plus cefepime (VC).

METHODS

A retrospective cohort study of adult patients admitted to an intensive care unit between September 2012 and December 2016 was conducted. Patients were included if they received combination therapy with VPT or VC for ≥48 hours. Patients were excluded if creatinine clearance was <60 mL/min or received renal replacement therapy prior to the initiation of therapy. The primary end point was AKI, as defined by the Acute Kidney Injury Network classification, during or within 48 hours of completion of therapy. The incidence of AKI was compared between groups and multivariate analysis was performed to control for relevant confounders.

RESULTS

A total of 394 patients received either VPT (n = 258) or VC (n = 136). There were no differences in baseline serum creatinine (0.8 [0.3]mg/dL vs 0.7 [0.3] mg/dL, P = 0.207), use of vasopressors (44% vs 38%, P = 0.255), mechanical ventilation (45% vs 40%, P = 0.350), or initial vancomycin trough (11.2 [5] mg/L vs 11 [4.8] mg/L, P = 0.668) between VPT and VC groups, respectively. The incidence of AKI was 28.7% for VPT patients versus 21.3% for VC patients (P = 0.114). Multivariate analysis revealed vancomycin trough >20 mg/L (odds ratio, OR [95% confidence interval, CI] = 2.69 [1.62-4.47]), baseline SCr (OR [95% CI] = 3.34 [1.43-7.80]), vasopressors (OR [95% CI] = 1.77 [1.04-3.04]), and duration of combination therapy (OR [95% CI] = 1.009 [1.003-1.015]) as independent risk factors for AKI.

CONCLUSION

The risk of AKI was similar between VPT and VC groups in critically ill patients. Risk factors for AKI were related to baseline renal function, duration of combination therapy, supratherapeutic vancomycin troughs, and severity of illness.

Comparative incidence and excess risk of acute kidney injury in hospitalised patients receiving vancomycin and piperacillin/tazobactam in combination or as monotherapy

Combination therapy with vancomycin and piperacillin/tazobactam (TZP) has been associated with increased risk of acute kidney injury (AKI) compared with monotherapy with either agent. This retrospective, matched cohort study was conducted to assess the comparative incidence of AKI due to combination therapy in patients receiving vancomycin and TZP in combination or as monotherapy. Patients aged ≥18 years admitted to Albany Medical Center (Albany, NY) between September 2013 and August 2014 who had received therapy for at least two consecutive days were included. Patients who were pregnant, neutropenic, had AKI on admission or with cystic fibrosis were excluded. Patients were matched on baseline risk of AKI. The main outcome of interest was AKI, defined as an increase in serum creatinine of ≥0.3 mg/L or ≥50% within 48 h. Secondary outcomes evaluated were length of hospital and ICU stay and inpatient mortality associated with AKI. The risk of AKI was 7.0%, 8.5% and 26.8% in the vancomycin monotherapy, TZP monotherapy and combination groups, respectively (P < 0.001). In the multivariate analysis, combination therapy was independently associated with an increased odds of AKI (adjusted odds ratio = 4.406, 95% confidence interval 1.472-13.188) compared with vancomycin monotherapy. The excess risk of combination therapy was 11.3%. In this matched cohort study, there was an increased incidence of AKI in patients receiving vancomycin and TZP combination therapy. Further research is needed to determine the individual strategies to best prevent inpatient AKI in patients receiving this combination therapy.