Ampicillin-Sulbactam for Carbapenem-Susceptible Acinetobacter baumannii Pneumonia: A Case for High-Dose, Continuous Infusion Dosing Strategy in the Trauma ICU.

Background: The optimal ampicillin-sulbactam dosing regimen for carbapenem-susceptible Acinetobacter baumannii isolates in critically ill trauma patients has not been clearly defined. One strategy to provide the adequate sulbactam dose includes high-dose continuous infusion. Case(s) Description: We present three cases of critically ill trauma patients with augmented renal clearance treated with high-dose ampicillin-sulbactam through an intravenous continuous infusion for ventilator-associated pneumonia. All A. baumannii isolates were susceptible to sulbactam with low minimum inhibitory concentrations. All achieved clinical cure at the end of therapy and no recurrent pneumonia was noted. No clinically substantial adverse effect attributable to ampicillin-sulbactam therapy occurred. Discussion: There is limited evidence to endorse high-dose, continuous infusion ampicillin-sulbactam for treatment of infections caused by carbapenem-susceptible A. baumannii. This report presents three critically ill trauma patients with augmented renal clearance that achieved positive clinical outcomes with higher doses of ampicillin-sulbactam administered through a continuous infusion.

Application of Monte Carlo simulation to optimise the dosage regimen of meropenem in patients with augmented renal clearance for Pseudomonas aeruginosa infection.

Objective: To optimise the dosing regimen of meropenem for treating Pseudomonas aeruginosa (PA) infections in critically ill patients with augmented renal clearance (ARC) using pharmacokinetic/pharmacodynamic (PK/PD) principles and Monte Carlo simulation (MCS). Methods: This research involves an MCS based on PK data from patients with ARC and a minimum inhibitory concentration (MIC) distribution of PA. This study simplifies the methods section, focusing on the critical aspects of simulation and target values for effective treatment. Results: The study highlights key findings and emphasises that tailored dosing based on bacterial MIC values is essential for patients with ARC. It also notes that empirical treatment in patients with ARC should consider the MIC distribution, with 2 g every (q) 6 h administered to achieve the PK/PD target, while 3 g q 6 h is effective in inhibiting resistance. Conclusion: Tailored dosing based on bacterial MIC values is crucial for patients with ARC. Prolonged infusion time alone does not enhance efficacy. Empirical treatment in patients with ARC should consider MIC distribution; a dosage of 2 g q 6 h achieves the PK/PD target, while 3 g q 6 h (≥12 g daily) inhibits resistance.

Validation of Two Scoring Tools to Predict Risk of Augmented Renal Clearance in Trauma Patients.

INTRODUCTION: Augmented renal clearance (ARC) is prevalent in trauma populations. Identification is underrecognized by calculated creatinine clearance or estimated glomerular filtration rate equations. Predictive scores may assist with ARC identification. The goal of this study was to evaluate validity of the ARCTIC score and ARC Predictor to predict ARC in critically ill trauma patients. METHODS: This single center, retrospective study was performed at an academic level 1 trauma center. Critically ill adult trauma patients undergoing 24-h urine-collection were included. Patients with serum creatinine >1.5 mg/dL, kidney replacement therapy, suspected rhabdomyolysis, chronic kidney disease, or inaccurate urine collection were excluded. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for ARCTIC Score and ARC Predictor were calculated. Receiver operating characteristic curves were created for ARCTIC score and ARC Predictor models. RESULTS: One-hundred and twenty-two patients with ARC and 78 patients without ARC were included. The ARCTIC score sensitivity, specificity, PPV, and NPV were 89%, 54%, 75%, and 75%, respectively. The ARC Predictor demonstrated sensitivity, specificity, PPV, and NPV of 77%, 88%, 91%, and 71%, respectively. Regression analyses revealed both ARCTIC score ≥6 and ARC Predictor threshold >0.5 as significant risk factors for ARC in presence of traumatic brain injury, obesity, injury severity score, and negative nitrogen balance (ARCTIC ≥6: odds ratio 8.59 [95% confidence interval 3.90-18.92], P < 0.001; ARC Predictor >0.5: odds ratio 20.07 [95% confidence interval 8.53-47.19], P < 0.001). CONCLUSIONS: These findings corroborate validity of two pragmatic prediction tools to identify patients at high risk of ARC. Future studies evaluating correlations between ARCTIC score, ARC Predictor, and clinical outcomes are warranted.

The Impact of Augmented Renal Clearance on Vancomycin Pharmacokinetics and Pharmacodynamics in Critically Ill Patients.

Augmented renal clearance (ARC), defined as a creatinine clearance (CrCl) > 130 mL/min/1.73 m2, is observed in 30-65% of critically ill patients. When following standard dosage guidelines, patients with ARC often experience subtherapeutic vancomycin levels, resulting in treatment failure due to accelerated drug elimination. This review aims to explore ARC's impact on vancomycin pharmacokinetics and pharmacodynamics (PK/PD) indices in ARC patients, seeking to identify an accurate dose adjustment method for this patient population. In September 2023, a comprehensive literature search was conducted on the MEDLINE and EMBASE databases to include all available studies providing information on the impact of ARC on vancomycin therapy in critically ill adults. Articles that studied the pediatric population and those with insufficient PK data were excluded. A total of 21 articles met the inclusion criteria. The findings revealed a positive correlation between CrCl and vancomycin clearance, indicating low serum concentrations. Therefore, upward dosing adjustments are necessary to improve treatment success. Younger age consistently emerged as a major contributor to ARC and vancomycin PK/PD alterations. This study summarizes the PK/PD alterations, current dosage recommendations and proposes preliminary recommendations on possible dosing approaches to decrease the risk of subtherapeutic exposure in this patient population.

Dosing Regimen for Cefotaxime Should Be Adapted to the Stage of Renal Dysfunction in Critically Ill Adult Patients-A Retrospective Study.

Cefotaxime administration is recommended in doses of 3-12 g/day in adults with a Glomerular Filtration Rate (GFR) > 5 mL/min. This study aimed to assess the impact of renal function and obesity on cefotaxime concentrations in intensive care unit (ICU) patients. A retrospective cohort study was conducted on consecutive ICU patients receiving continuous cefotaxime infusion between 2020 and 2022 [IRBN992021/CHUSTE]. Doses were not constant; consequently, a concentration-to-dose ratio (C/D) was considered. Statistical analysis was performed to assess the relationship between cefotaxime concentrations, renal function, and obesity. A total of 70 patients, median age 61 years, were included, with no significant difference in cefotaxime concentrations between obese and non-obese patients. However, concentrations varied significantly by GFR, with underdosing prevalent in patients with normal to increased renal function and overdosing in those with severely impaired renal function. Adjustment of cefotaxime dosing according to GFR was associated with improved target attainment. Cefotaxime dosing in critically ill patients should consider renal function, with higher initial doses required in patients with normal to increased GFR and lower doses in those with severely impaired renal function. Therapeutic drug monitoring may aid in optimising dosing regimens. Prospective studies are warranted to validate these findings and inform clinical practice.

Quantification of meropenem in serum and cerebrospinal fluid in children with bacterial meningitis with augmented renal clearance by UPLC-MS/MS.

Meropenem is an ultrabroad-spectrum antimicrobial agent that is often recommended for the treatment of bacterial meningitis (BM) in children. However, a subtherapeutic phenomenon occurred in BM children complicated with augmented renal clearance (ARC) at the recommended dose of meropenem. To support its pharmacokinetics, a sensitive, fast and robust ultra-liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed to measure meropenem concentrations in serum and cerebrospinal fluid (CSF). The method involved protein precipitation, and samples were diluted with a large proportion of water to eliminate solvent effects. The separation of samples was performed on a Waters Acquity™ BEH C18 column (2.1 × 50 mm i.d., 1.7 µm) with a gradient profile. The mobile phases were formic acid-water (1:1000, v/v) and acetonitrile. The linear range was good, with a concentration range of 0.100-100 µg/mL for serum and 0.0400-20.0 µg/mL for CSF. The intra-day and inter-day precisions were less than 8.0%, and the intra-day and inter-day accuracies varied -6.6% from 6.5% for the both serum and CSF. The selectivity, carry-over, dilution integrity, matrix effect, recovery and stability were validated according to international guidelines. The developed UPLC-MS/MS method successfully determined the meropenem concentrations in the serum and CSF of children with BM complicated with ARC. The results indicated that under the recommended dosing regimen (40 mg/kg every 8 h), the time to reach the effective treatment target of 50%T > MIC was only approximately 3 h and lower CSF concentrations of meropenem were observed in children with BM with ARC.

Clinical Outcomes of Protocolized Antibiotic Dosing in Critically Ill Surgical Patients With Bacteremia and Augmented Renal Clearance Compared With Critically Ill Surgical Patients Without Augmented Renal Clearance.

Background: Augmented renal clearance (ARC) is a phenomenon observed in critically ill patients, leading to supraphysiologic drug clearance and concern for suboptimal antibiotic concentrations. The purpose of this study was to compare the clinical outcomes of our institutional protocolized antibiotic dosing regimen in critically ill patients with bacteremia and ARC compared with critically ill patients without ARC. Patients and Methods: We performed a retrospective study comparing the efficacy of an institutional protocolized antibiotic dosing regimen in critically ill patients with bacteremia and ARC compared with critically ill patients without ARC. The primary end point was in-hospital mortality. Secondary outcomes were intensive care unit (ICU) mortality, days requiring mechanical ventilation, ICU length of stay (LOS), hospital LOS, development of drug resistance to index antibiotic agent, and documented clearance of blood cultures within 72 hours. Results: There were 75 patients included in this study. Twenty percent of patients in the ARC group died in the hospital versus 31% in the non-ARC group (p = 0.26). The results for the ARC group versus the non-ARC group for the secondary outcomes of ICU mortality (20% vs. 26%; p = 0.56), ICU LOS (14.7 days vs. 7 days; p = 0.07), hospital LOS (28.3 days vs. 21.6 days; p = 0.03), days requiring mechanical ventilation (14 days vs. 12 days; p = 0.49), duration of antibiotic therapy (7.5 days vs. 9.0 days; p = 0.39), documented clearance of blood cultures within 72 hours (41% vs. 33%; p = 0.56), and the development of drug resistance to the index antibiotic agent (0% vs. 0%; p > 0.99) were also calculated. Conclusions: Among critically ill patients with bacteremia and ARC, there was no difference in in-hospital mortality compared with critically ill patients without ARC. There was a difference in hospital LOS, with a shorter duration of stay for the non-ARC group. There was no development of multi-drug-resistant organisms in either group.

Meropenem pharmacokinetic/pharmacodynamic target attainment and clinical response in ICU patients: A prospective observational study.

BACKGROUND: Several studies report lack of meropenem pharmacokinetic/pharmacodynamic (PK/PD) target attainment (TA) and risk of therapeutic failure with intermittent bolus infusions in intensive care unit (ICU) patients. The aim of this study was to describe meropenem TA in an ICU population and the clinical response in the first 72 h after therapy initiation. METHODS: A prospective observational study of ICU patients ≥18 years was conducted from 2014 to 2017. Patients with normal renal clearance (NRC) and augmented renal clearance (ARC) and patients on continuous renal replacement therapy (CRRT) were included. Meropenem was administered as intermittent bolus infusions, mainly at a dose of 1 g q6h. Peak, mid, and trough levels were sampled at 24, 48, and 72 h after therapy initiation. TA was defined as 100% T > 4× MIC or trough concentration above 4× MIC. Meropenem PK was estimated using traditional calculation methods and population pharmacokinetic modeling (P-metrics®). Clinical response was evaluated by change in C-reactive protein (CRP), Sequential Organ Failure Assessment (SOFA) score, leukocyte count, and defervescence. RESULTS: Eighty-seven patients were included, with a median Simplified Acute Physiology (SAPS) II score 37 and 90 days mortality rate of 32%. Median TA was 100% for all groups except for the ARC group with 45.5%. Median CRP fell from 175 (interquartile range [IQR], 88-257) to 70 (IQR, 30-114) (p < .001) in the total population. A reduction in SOFA score was observed only in the non-CRRT groups (p < .001). CONCLUSION: Intermittent meropenem bolus infusion q6h gives satisfactory TA in an ICU population with variable renal function and CRRT modality, except for ARC patients. No consistent relationship between TA and clinical endpoints were observed.

Enhanced renal clearance impacts levetiracetam concentrations in patients with traumatic brain injury with and without augmented renal clearance.

BACKGROUND: The purpose of this study was to examine the impact of ARC on levetiracetam concentrations during the first week following acute TBI. The hypothesis was levetiracetam concentrations are significantly lower in TBI patients with augmented renal clearance (ARC) compared to those with normal renal clearance. METHODS: This is a prospective cohort pharmacokinetic study of adults with moderate to severe TBI treated with levetiracetam during the first week after injury. Serial blood collections were performed daily for analysis of levetiracetam, cystatin C, and 12-hr creatinine clearance (CrCl) determinations. Patients were divided into two cohorts: with (CrCl ≥130 ml/min/1.73 m2) and without ARC. RESULTS: Twenty-two patients with moderate to severe TBI were included. The population consisted primarily of young male patients with severe TBI (mean age 40 years old, 68% male, median admission GCS 4). Each received levetiracetam 1000 mg IV every 12 h for the study period. ARC was present in 77.3% of patients, with significantly lower levetiracetam concentrations in ARC patients and below the conservative therapeutic range (< 6mcg/mL) for all study days. In patients without ARC, the serum concentrations were also below the expected range on all but two study days (Days 4 and 5). Four of the 22 (18.2%) patients exhibited seizure activity during the study period (two of these patients exhibited ARC). Cystatin C concentrations were significantly lower in patients with ARC, though the mean for all patients was within the typical normal range. CONCLUSIONS: ARC has a high prevalence in patients with moderate to severe TBI. Levetiracetam concentrations after standard dosing were low in all TBI patients, but significantly lower in patients with ARC. This study highlights the need to consider personalized drug dosing in TBI patients irrespective of the presence of ARC. CLINICAL TRIAL REGISTRATION: This study was registered at cliicaltrials.gov (NCT02437838) Registered on 08/05/2015, https://clinicaltrials.gov/ct2/show/NCT02437838 .

Impact of augmented renal clearance on anticoagulant therapy in critically ill patients with coronavirus disease 2019: A retrospective cohort study.

INTRODUCTION: This study aimed to determine the impact of augmented renal clearance (ARC) on anticoagulation therapy in critically ill patients with coronavirus disease 2019 (COVID-19). METHODS: This retrospective cohort study included adult patients with severe COVID-19 with ARC who had been treated at our hospital between 2020 and 2021. We measured the estimated glomerular filtration rate calculated by the Chronic Kidney Disease Epidemiology Collaboration formula (eGFRCKD-EPI) every morning, and ARC condition was defined as eGFRCKD-EPI ≥ 130 mL/min/1.73 m2. Multivariate regression analysis with Huber-White sandwich estimator was performed to examine the association of unfractionated heparin (UH) dosage between blood test timings with activated partial thromboplastin time (APTT) compared with and without ARC. RESULTS: We identified 38 enrolled patients: seven and 31 in the ARC and non-ARC groups, respectively. In the ARC coexisting condition, a higher dose of UH, which corresponded to the total dose in 24 h from the previous day, was required to achieve the same APTT prolongation, with a significant difference (p < 0.001). CONCLUSIONS: Our study suggests that careful monitoring and consideration of higher UH doses in critically ill patients with COVID-19 is necessary because anticoagulation failure can occur during ARC.

Potential benefits of therapeutic drug monitoring for beta-lactam antibiotics in augmented renal clearance patients: a case report.

Augmented renal clearance (ARC) is commonly described in critically ill patients, making drug pharmacokinetics even harder to predict in this population. This case report displays the value of therapeutic drug monitoring (TDM) of piperacillin/tazobactam (PTZ) in this population. We identified two patients with ARC and intermittent administration of PTZ who took part in a prospective, descriptive study conducted at Hôpital du Sacré-Cœur de Montréal. Both had plasma samples drawn at peak, middle, and end of their dosing intervals of PTZ. Minimal inhibitory concentrations (MICs) of 4 and 8 mg/L were chosen to evaluate therapeutic target attainment at middle and end of dosing interval. The first patient was a 52-year-old male with a renal clearance rate estimated at 147 mL/min who received 3.375 g PTZ every 6 h. The second patient, a 49-year-old male, had an estimated renal clearance rate of 163 mL/min and received the same regimen. Both patients had piperacillin concentrations above the target MICs at middle of the dosing interval, but they failed to reach a trough concentration above 8 mg/L. The present case report showcases two patients with subtherapeutic PTZ concentrations despite strict following of local administration protocols. This suboptimal administration could not only lead to treatment failure, but also to the selection and growth of resistant pathogens. Implementing TDM would offer the possibility to adjust drug regimens in real-time and prevent situations like these from occurring.

Personalized application of antimicrobial drugs in pediatric patients with augmented renal clearance: a review of literature.

The effect of renal functional status on drug metabolism is a crucial consideration for clinicians when determining the appropriate dosage of medications to administer. In critically ill patients, there is often a significant increase in renal function, which leads to enhanced drug metabolism and potentially inadequate drug exposure. This phenomenon, known as augmented renal clearance (ARC), is commonly observed in pediatric critical care settings. The findings of the current study underscore the significant impact of ARC on the pharmacokinetics and pharmacodynamics of antimicrobial drugs in critically ill pediatric patients. Moreover, the study reveals a negative correlation between increased creatinine clearance and blood concentrations of antimicrobial drugs. The article provides a comprehensive review of ARC screening in pediatric patients, including its definition, risk factors, and clinical outcomes. Furthermore, it summarizes the dosages and dosing regimens of commonly used antibacterial and antiviral drugs for pediatric patients with ARC, and recommendations are made for dose and infusion considerations and the role of therapeutic drug monitoring. CONCLUSION:  ARC impacts antimicrobial drugs in pediatric patients. WHAT IS KNOWN: • ARC is inextricably linked to the failure of antimicrobial therapy, recurrence of infection, and subtherapeutic concentrations of drugs. WHAT IS NEW: • This study provides an updated overview of the influence of ARC on medication use and clinical outcomes in pediatric patients. • In this context, there are several recommendations for using antibiotics in pediatric patients with ARC: 1) increase the dose administered; 2) prolonged or continuous infusion administration; 3) use of TDM; and 4) use alternative drugs that do not undergo renal elimination.

Predictors of augmented renal clearance based on iohexol plasma clearance in critically ill children.

BACKGROUND: Augmented renal clearance (ARC) holds a risk of subtherapeutic drug concentrations. Knowledge of patient-, disease-, and therapy-related factors associated with ARC would allow predicting which patients would benefit from intensified dosing regimens. This study aimed to identify ARC predictors and to describe ARC time-course in critically ill children, using iohexol plasma clearance (CLiohexol) to measure glomerular filtration rate (GFR). METHODS: This is a retrospective analysis of data from the "IOHEXOL" study which validated GFR estimating formulas (eGFR) against CLiohexol. Critically ill children with normal serum creatinine were included, and CLiohexol was performed as soon as possible after pediatric intensive care unit (PICU) admission (CLiohexol1) and repeated (CLiohexol2) after 48-72 h whenever possible. ARC was defined as CLiohexol exceeding normal GFR for age plus two standard deviations. RESULTS: Eighty-five patients were included; 57% were postoperative patients. Median CLiohexol1 was 122 mL/min/1.73 m2 (IQR 75-152). Forty patients (47%) expressed ARC on CLiohexol1. Major surgery other than cardiac surgery and eGFR were found as independent predictors of ARC. An eGFR cut-off value of 99 mL/min/1.73 m2 and 140 mL/min/1.73 m2 was suggested to identify ARC in children under and above 2 years, respectively. ARC showed a tendency to persist on CLiohexol2. CONCLUSIONS: Our findings raise PICU clinician awareness about increased risk for ARC after major surgery and in patients with eGFR above age-specific thresholds. This knowledge enables identification of patients with an ARC risk profile who would potentially benefit from a dose increase at initiation of treatment to avoid underexposure. TRIAL REGISTRATION: ClinicalTrials.gov NCT05179564, registered retrospectively on January 5, 2022.

Analysis of Pharmacokinetics/Pharmacodynamics Compliance and Influencing Factors of Meropenem Concentration in Patients with Augmented Renal Clearance / 医药导报

Objective To explore the pharmacokinetics/pharmacodynamics(PK/PD)parameters and influencing factors in patients with augmented renal clearance(ARC)to provide the basis for the rational use of meropenem.Methods Using the method of retrospective study,the patients with increased renal clearance who used meropenem monitored the concentration from January 2018 to December 2021.The PK/PD parameters of meropenem were analyzed,and multiple linear retrospective analyses discussed the influencing factors of meropenem valley concentration.Results A total of 58 patients were included in the study,and the trough concentration was 1.35[0.23,1.86]μg·mL-1,taking 100%fT＞MIC as PK/PD target value,the compliance rate was 20.69%.The compliance rate of daily dose＜3 g·d-1 was 8.70%,and≥3 g·d-1 was 31.43%,the difference was statistically significant.With MIC of 0.5,1,2,4,and 8 μg·mL-1,PK/PD compliance rates were 62.07%,48.28%,20.69%,8.62%and 0.Respectively.Multiple linear retrospective analyses showed that dose was an independent factor affecting meropenem valley concentration.Conclusion The PK/PD compliance rate of meropenem in patients with augmented renal clearance is low,even if MIC≤0.5 μg·mL-1,the routine dose is difficult to achieve the ideal PK/PD,so the clinical should recognize ARC and perform TDM as soon as possible,and use TDM to guide the medication regimen of meropenem for ARC patients.

Augmented renal clearance in septic patients with antibiotic blood concentration / 中国小儿急救医学

Augmented renal clearance（ARC）can be caused by the disease itself，inflammatory state，or therapeutic interventions，and is often associated with severe infections and trauma.Sepsis is one of the most important diseases with high morbidity and mortality in the world.Current studies suggest that ARC is significantly associated with inadequate antimicrobial therapy concentration in patients with sepsis，increasing the risk of clinical treatment failure.It is important to optimize the drug administration strategy for patients with ARC in sepsis，although the current clinical screening of ARC is not yet perfect.This review summarized the literature on changes in blood concentration of antibiotics and administration strategies in patients with sepsis with ARC，in order to provide appropriate medication and clinical guidance for ARC patients.

A descriptive pharmacokinetic/pharmacodynamic analysis of ceftazidime-avibactam in a case series of critically ill patients with augmented renal clearance.

To describe the pharmacokinetics/pharmacodynamics (PK/PD) of a 2 h infusion of ceftazidime-avibactam (CAZ-AVI) in critically ill patients with augmented renal clearance (ARC). A retrospective review of all critically ill patients with ARC who were treated with CAZ-AVI between August 2020 and May 2023 was conducted. Patients whose 12-h creatinine clearance prior to CAZ-AVI treatment and steady-state concentration (Css) of CAZ-AVI were both monitored were enrolled. The free fraction (fCss) of CAZ-AVI was calculated from Css. The joint PK/PD targets of CAZ-AVI were considered optimal when a Css/minimum inhibitory concentration (MIC) ratio for CAZ ≥4 (equivalent to 100% fT > 4 MIC) and a Css/CT ratio of AVI >1 (equivalent to 100% fT > CT 4.0 mg/L) were reached simultaneously, quasioptimal when only one of the two targets was reached, and suboptimal when neither target was reached. The relationship between PK/PD goal achievement, microbial eradication and the clinical efficacy of CAZ-AVI was evaluated. Four patients were included. Only one patient achieved optimal joint PK/PD targets, while the other three reached suboptimal targets. The patient with optimal PK/PD targets achieved microbiological eradication, while the other three patients did not, but all four patients achieved good clinical efficacy. Standard dosages may not enable most critically ill patients with ARC to reach the optimal joint PK/PD targets of CAZ-AVI. Optimal drug dose adjustment of CAZ-AVI in ARC patients requires dynamic drug concentration monitoring.

KIM-1, IL-18, and NGAL, in the Machine Learning Prediction of Kidney Injury among Children Undergoing Hematopoietic Stem Cell Transplantation-A Pilot Study.

Children undergoing allogeneic hematopoietic stem cell transplantation (HSCT) are prone to developing acute kidney injury (AKI). Markers of kidney damage: kidney injury molecule (KIM)-1, interleukin (IL)-18, and neutrophil gelatinase-associated lipocalin (NGAL) may ease early diagnosis of AKI. The aim of this study was to assess serum concentrations of KIM-1, IL-18, and NGAL in children undergoing HSCT in relation to classical markers of kidney function (creatinine, cystatin C, estimated glomerular filtration rate (eGFR)) and to analyze their usefulness as predictors of kidney damage with the use of artificial intelligence tools. Serum concentrations of KIM-1, IL-18, NGAL, and cystatin C were assessed by ELISA in 27 children undergoing HSCT before transplantation and up to 4 weeks after the procedure. The data was used to build a Random Forest Classifier (RFC) model of renal injury prediction. The RFC model established on the basis of 3 input variables, KIM-1, IL-18, and NGAL concentrations in the serum of children before HSCT, was able to effectively assess the rate of patients with hyperfiltration, a surrogate marker of kidney injury 4 weeks after the procedure. With the use of the RFC model, serum KIM-1, IL-18, and NGAL may serve as markers of incipient renal dysfunction in children after HSCT.

Real-Life Vancomycin Therapeutic Drug Monitoring in Coagulase-Negative Staphylococcal Bacteremia in Neonatal and Pediatric Intensive Care Unit: Are We Underestimating Augmented Renal Clearance?

Bloodstream infections (BSI) from coagulase-negative-staphylococci (CoNS) are among the most frequent healthcare-related infections. Their treatment involves the use of vancomycin, a molecule whose optimal pharmacokinetic/pharmacodynamic (PK/PD) target for efficacy and safety is an area-under-curve/minimum inhibitory concentration (AUC/MIC) ratio ≥ 400 with AUC < 600. BSIs from CoNS in pediatric and neonatal intensive care unit that occurred at the Gaslini Institute over five years were evaluated to investigate the efficacy of vancomycin therapy in terms of achieving the desired PK/PD target and determining whether any variables interfere with the achievement of this target. AUC/MIC ≥ 400 with AUC < 600 at 48 and 72 h after therapy initiation was achieved in only 21% of the neonatal population and 25% of the pediatric population. In the pediatric population, an inverse correlation emerged between estimated glomerular filtration rate (eGFR) and achieved AUC levels. Median eGFR at 72 h was significantly higher (expression of hyperfiltration) in events with AUC < 400, compared with those with AUC ≥ 400 (p < 0.001). A cut-off value of eGFR in the first 72 h has been identified (145 mL/min/1.73 m2), beyond which it is extremely unlikely to achieve an AUC ≥ 400, and therefore a higher dose or a different antibiotic should be chosen.

Role of a Real-Time TDM-Based Expert Clinical Pharmacological Advice Program in Optimizing the Early Pharmacokinetic/Pharmacodynamic Target Attainment of Continuous Infusion Beta-Lactams among Orthotopic Liver Transplant Recipients with Documented or Suspected Gram-Negative Infections.

(1) Objectives: To describe the attainment of optimal pharmacokinetic/pharmacodynamic (PK/PD) targets in orthotopic liver transplant (OLT) recipients treated with continuous infusion (CI) beta-lactams optimized using a real-time therapeutic drug monitoring (TDM)-guided expert clinical pharmacological advice (ECPA) program during the early post-surgical period. (2) Methods: OLT recipients admitted to the post-transplant intensive care unit over the period of July 2021-September 2023, receiving empirical or targeted therapy with CI meropenem, piperacillin-tazobactam, meropenem-vaborbactam, or ceftazidime-avibactam optimized using a real-time TDM-guided ECPA program, were retrospectively retrieved. Steady-state beta-lactam (BL) and/or beta-lactamase inhibitor (BLI) plasma concentrations (Css) were measured, and the Css/MIC ratio was selected as the best PK/PD target for beta-lactam efficacy. The PK/PD target of meropenem was defined as being optimal when attaining a fCss/MIC ratio > 4. The joint PK/PD target of the BL/BLI combinations (namely piperacillin-tazobactam, ceftazidime-avibactam, and meropenem-vaborbactam) was defined as being optimal when the fCss/MIC ratio > 4 of the BL and the fCss/target concentration (CT) ratio > 1 of tazobactam or avibactam, or the fAUC/CT ratio > 24 of vaborbactam were simultaneously attained. Multivariate logistic regression analysis was performed for testing potential variables that were associated with a failure in attaining early (i.e., at first TDM assessment) optimal PK/PD targets. (3) Results: Overall, 77 critically ill OLT recipients (median age, 57 years; male, 63.6%; median MELD score at transplantation, 17 points) receiving a total of 100 beta-lactam treatment courses, were included. Beta-lactam therapy was targeted in 43% of cases. Beta-lactam dosing adjustments were provided in 76 out of 100 first TDM assessments (76.0%; 69.0% decreases and 7.0% increases), and overall, in 134 out of 245 total ECPAs (54.7%). Optimal PK/PD target was attained early in 88% of treatment courses, and throughout beta-lactam therapy in 89% of cases. Augmented renal clearance (ARC; OR 7.64; 95%CI 1.32-44.13) and MIC values above the EUCAST clinical breakpoint (OR 91.55; 95%CI 7.12-1177.12) emerged as independent predictors of failure in attaining early optimal beta-lactam PK/PD targets. (4) Conclusion: A real-time TDM-guided ECPA program allowed for the attainment of optimal beta-lactam PK/PD targets in approximately 90% of critically ill OLT recipients treated with CI beta-lactams during the early post-transplant period. OLT recipients having ARC or being affected by pathogens with MIC values above the EUCAST clinical breakpoint were at high risk for failure in attaining early optimal beta-lactam PK/PD targets. Larger prospective studies are warranted for confirming our findings.