American Board of Internal Medicine Nephrology Procedure Requirements for Initial Certification: Time for a Change and Pursuing Consensus in the Nephrology Community.

In 1988, the American Board of Internal Medicine (ABIM) defined essential procedural skills in nephrology, and candidates for ABIM certification were required to present evidence of possessing the skills necessary for placement of temporary dialysis vascular access, hemodialysis, peritoneal dialysis, and percutaneous renal biopsy. In 1996, continuous renal replacement therapy was added to the list of nephrology requirements. These procedure requirements have not been modified since 1996 while the practice of nephrology has changed dramatically. In March 2021, the ABIM Nephrology Board embarked on a policy journey to revise the procedure requirements for nephrology certification. With the guidance of nephrology diplomates, training program directors, professional and patient organizations, and other stakeholders, the ABIM Nephrology Board revised the procedure requirements to reflect current practice and national priorities. The approved changes include the Opportunity to Train standard for placement of temporary dialysis catheters, percutaneous kidney biopsies, and home hemodialysis, which better reflects the current state of training in most training programs, and the new requirements for home dialysis therapies training will align with the national priority to address the underuse of home dialysis therapies. This perspective details the ABIM process for considering changes to the certification procedure requirements and how ABIM collaborated with the larger nephrology community in considering revisions and additions to these requirements.

Moving toward a contemporary classification of drug-induced kidney disease.

Drug-induced kidney disease (DIKD) accounts for about one-fourth of all cases of acute kidney injury (AKI) in hospitalized patients, especially in critically ill setting. There is no standard definition or classification system of DIKD. To address this, a phenotype definition of DIKD using expert consensus was introduced in 2015. Recently, a novel framework for DIKD classification was proposed that incorporated functional change and tissue damage biomarkers. Medications were stratified into four categories, including "dysfunction without damage," "damage without dysfunction," "both dysfunction and damage," and "neither dysfunction nor damage" using this novel framework along with predominant mechanism(s) of nephrotoxicity for drugs and drug classes. Here, we briefly describe mechanisms and provide examples of drugs/drug classes related to the categories in the proposed framework. In addition, the possible movement of a patient's kidney disease between certain categories in specific conditions is considered. Finally, opportunities and barriers to adoption of this framework for DIKD classification in real clinical practice are discussed. This new classification system allows congruencies for DIKD with the proposed categorization of AKI, offering clarity as well as consistency for clinicians and researchers.

Drug dosing considerations in continuous renal replacement therapy.

Acute kidney injury (AKI) is a common complication in critically ill patients, which is associated with increased in-hospital mortality. Delivering effective antibiotics to treat patients with sepsis receiving continuous renal replacement therapy (RRT) is complicated by variability in pharmacokinetics, dialysis delivery, lack of primary literature, and therapeutic drug monitoring. Pharmacokinetic alterations include changes in absorption, distribution, protein binding (PB), metabolism, and renal elimination. Drug absorption may be significantly changed due to alterations in gastric pH, perfusion, gastrointestinal motility, and intestinal atrophy. Volume of distribution for hydrophilic drugs may be increased due to volume overload. Estimation of renal clearance is challenged by the effective delivery of RRT. Drug characteristics such as PB, volume of distribution, and molecular weight impact removal of the drug by RRT. The totality of these alterations leads to reduced exposure. Despite our best knowledge, therapeutic drug monitoring of patients receiving continuous RRT demonstrates wide variability in antimicrobial concentrations, highlighting the need for expanded monitoring of all drugs. This review article will focus on changes in drug pharmacokinetics in AKI and dosing considerations to attain antibiotic pharmacodynamic targets in critically ill patients receiving continuous RRT.

Urinary Exosomes Identify Inflammatory Pathways in Vancomycin Associated Acute Kidney Injury.

BACKGROUND: Vancomycin is commonly used as a first line therapy for gram positive organisms such as methicillin resistant Staphylococcusaureus. Vancomycin-induced acute kidney injury (V-AKI) has been reported in up to 43% of patients, especially in those with higher targeted trough concentrations. The precise mechanism of injury in humans remains elusive, with recent evidence directed towards proximal tubule cell apoptosis. In this study, we investigated the protein contents of urinary exosomes in patients with V-AKI to further elucidate biomarkers of mechanisms of injury and potential responses. METHODS: Urine samples from patients with V-AKI who were enrolled in the DIRECT study and matched healthy controls from the UAB-UCSD O'Brien Center Biorepository were included in the analysis. Exosomes were extracted using solvent exclusion principle and polyethylene glycol induced precipitation. Protein identity and quantification was determined by label-free liquid chromatography mass spectrometry (LC/MS). The mean peak serum creatinine was 3.7 ± 1.4 mg/dL and time to kidney injury was 4.0 ± 3.0 days. At discharge, 90% of patients demonstrated partial recovery; 33% experienced full recovery by day 28. Proteomic analyses on five V-AKI and 7 control samples revealed 2009 proteins in all samples and 251 proteins significantly associated with V-AKI (Pi-score > 1). The top discriminatory proteins were complement C3, complement C4, galectin-3-binding protein, fibrinogen, alpha-2 macroglobulin, immunoglobulin heavy constant mu and serotransferrin. CONCLUSION: Urinary exosomes reveal up-regulation of inflammatory proteins after nephrotoxic injury in V-AKI. Further studies are necessary in a large patient sample to confirm these findings for elucidation of pathophysiologic mechanisms and validation of potential injury biomarkers.

Low dose posaconazole delayed release tablets for fungal prophylaxis in lung transplant recipients.

In November 2013, posaconazole delayed release (DR) tablets were approved by the FDA with the labeled dose of 300 mg daily for fungal prophylaxis. There are no studies demonstrating the appropriate dose in lung transplant recipients (LTR). We performed a 2-center retrospective cohort study of LTR taking posaconazole DR tablets for prophylaxis between January 2014 and January 2017. Mean serum trough concentrations and percentage of measurements ≥0.7 mcg/mL were compared by daily dose. Forty-nine subjects with 156 steady state serum posaconazole concentrations were included. There was a significant difference in percentage of first measured concentration ≥0.7 mcg/mL by initial daily dose (P = .04). The mean serum posaconazole concentration by dose was 0.9 (±0.42) mcg/mL for 100 mg daily, 1.66 (±0.91) mcg/mL for 200 mg daily, 2.39 (±1.49) mcg/mL for 300 mg daily, and 1.75 (±0.21) mcg/mL for 400 mg daily (P < .001). Mean concentrations were at goal in 63.3%, 96.9%, 94.9%, and 100% of subjects taking 100 mg, 200 mg, 300 mg, and 400 mg daily respectively (P = .04). Our results suggest that doses less than 300 mg daily of posaconazole DR tablets may be adequate to achieve target serum concentrations in LTR. Larger studies are needed to confirm these findings.

Drug-induced kidney disease in the ICU: mechanisms, susceptibility, diagnosis and management strategies.

PURPOSE OF REVIEW: Acute kidney injury (AKI) is a common complication in the critically ill population, is multifactorial and associated with increased mortality. Drug-induced kidney injury is a significant contributor to the development of AKI. The purpose of this review is to provide updates in the epidemiology, susceptibility and management of drug-induced kidney disease (DIKD). RECENT FINDINGS: Recent changes in guidelines for the management of serious infections in the critically ill have resulted in an increased frequency of DIKD. Varying definitions employed in clinical trials has complicated the awareness of this adverse event. Causality assessment is often missing from studies as it is complicated by the need to evaluate competing AKI risk factors. This has led to uncertainty in the nephrotoxic risk of commonly used drugs. SUMMARY: Standard criteria for DIKD should be applied in clinical trials to improve our understanding of the frequency of these events. Adjudication of these events will improve the clinician's ability to evaluate the causal relationship and relative contribution of specific drugs to the AKI event.

The 6R's of drug induced nephrotoxicity.

Drug induced kidney injury is a frequent adverse event which contributes to morbidity and increased healthcare utilization. Our current knowledge of drug induced kidney disease is limited due to varying definitions of kidney injury, incomplete assessment of concurrent risk factors and lack of long term outcome reporting. Electronic surveillance presents a powerful tool to identify susceptible populations, improve recognition of events and provide decision support on preventative strategies or early intervention in the case of injury. Research in the area of biomarkers for detecting kidney injury and genetic predisposition for this adverse event will enhance detection of injury, identify those susceptible to injury and likely mitigate risk. In this review we will present a 6R framework to identify and mange drug induced kidney injury - risk, recognition, response, renal support, rehabilitation and research.

Phenotype standardization for drug-induced kidney disease.

Drug-induced kidney disease is a frequent cause of renal dysfunction; however, there are no standards to identify and characterize the spectrum of these disorders. We convened a panel of international, adult and pediatric, nephrologists and pharmacists to develop standardized phenotypes for drug-induced kidney disease as part of the phenotype standardization project initiated by the International Serious Adverse Events Consortium. We propose four phenotypes of drug-induced kidney disease based on clinical presentation: acute kidney injury, glomerular, tubular, and nephrolithiasis, along with the primary and secondary clinical criteria to support the phenotype definition, and a time course based on the KDIGO/AKIN definitions of acute kidney injury, acute kidney disease, and chronic kidney disease. Establishing causality in drug-induced kidney disease is challenging and requires knowledge of the biological plausibility for the specific drug, mechanism of injury, time course, and assessment of competing risk factors. These phenotypes provide a consistent framework for clinicians, investigators, industry, and regulatory agencies to evaluate drug nephrotoxicity across various settings. We believe that this is the first step to recognizing drug-induced kidney disease and developing strategies to prevent and manage this condition.

Impact of single immunosuppressive drug withdrawal on lymphocyte immunoreactivity.

BACKGROUND: Chronic rejection is a major cause of graft loss in kidney transplant recipients. Nonadherence to drug therapy is a well-recognized cause of chronic rejection leading to long-term graft dysfunction and failure for transplant recipients. Immunosuppressive medications with short half-lives that require frequent dosing, such as tacrolimus, complicate transplant regimens and may increase noncompliance. Regimens could be simplified using drugs with long half-lives requiring once-daily administration, such as sirolimus. The impact of missing doses of single agents has not been studied extensively. Erratic compliance or temporary discontinuation of immunosuppressive drugs may have significant implications for chronic rejection. METHODS: Our study evaluated the impact of single drug withdrawal of commonly used immunosuppressive agents (sirolimus and tacrolimus) on lymphocyte responses. We analyzed lymphocyte proliferation, cytokine secretion, and adenosine triphosphate generation using a crossover study design with normal healthy patients. Lymphocyte proliferation was assessed using 5-bromo-2-deoxyuridine incorporation, and T cell function was analyzed by examining adenosine triphosphate generation. RESULTS: Our results indicate that sirolimus exerts prolonged suppression of lymphocyte proliferation and decreased interleukin 17A that lasts up to 48 h after drug withdrawal. In comparison, tacrolimus did not have a similar effect on lymphocyte proliferation or interleukin 17A secretion. CONCLUSION: Future analysis of sirolimus in diverse transplantation populations merits investigation.

SGLT-2 Inhibitors Versus GLP-1 Receptor Agonists Effects on Kidney and Clinical Outcomes in Veterans with Type 2 Diabetes.

BACKGROUND: The primary aim compared kidney endpoints between patients with type 2 diabetes (T2D) 36 months after initiation on a sodium-glucose cotransporter-2 inhibitor (SGLT2i) or a GLP-1 receptor agonist (GLP-1RA). Secondary aims compared estimated glomerular filtration rate (eGFR), hemoglobin A1c (HbA1c), weight, and urine albumin-to-creatinine ratio (UACR) changes. METHODS: We conducted a retrospective cohort study of propensity score matched veterans with T2D, baseline eGFR>20mL/min/1.73m2, and initiated on a SGLT2i vs GLP-1RA between 4/1/2009-9/1/2020. Cox proportional hazard models were constructed to evaluate effectiveness between both groups on composite endpoint (decline of >=40% in eGFR from baseline, ESRD event, and all-cause mortality) and its components adjusting for baseline characteristics. Spline models were constructed to evaluate eGFR change and linear mixed effects models were constructed to evaluate changes in HbA1c, weight, and UACR. We used an intent-to-treat (ITT) approach as our main analysis followed by a per-protocol (PP) approach excluding veterans who discontinued or switched therapy during the study period. RESULTS: A total of 29,146 propensity score matched veterans were included in SGLT2i and GLP-1RA groups (14,573 per group). In the ITT and PP analyses, veterans initiated on SGLT2i had a 35% (HR=0.65; 95% CI: 0.62, 0.68) and 34% (HR=0.66; 95% CI: 0.62, 0.69) reduction in the hazard of experiencing the composite endpoint compared to veterans initiated on GLP-1RA adjusting for baseline characteristics, respectively. Between 6-36 months, we found an improved chronic eGFR slope with SGLT2i compared to GLP-1RA in both ITT and PP analyses; +1.19 mL/min/1.73 m2 (95% CI: 0.93, 1.45) and +1.29 mL/min/1.73m2 (95% CI: 1.01, 1.57), respectively. The annual difference in chronic eGFR slope in both ITT and PP analyses were +0.97 mL/min/1.73m2/year (95% CI: 0.82, 1.11) and +1.08 mL/min/1.73m2/year (95% CI: 0.92, 1.25). Improved HbA1c, weight loss and UACR were reported for both groups. CONCLUSION: In this real-world study, veterans with T2D initiated on SGLT2i were associated with reduced hazard of experiencing mortality, worsening eGFR, or developing ESRD and improved glycemic, metabolic, and renal endpoints compared to GLP-1RA use.

Development and validation of a deep learning algorithm for the prediction of serum creatinine in critically ill patients.

Objectives: Serum creatinine (SCr) is the primary biomarker for assessing kidney function; however, it may lag behind true kidney function, especially in instances of acute kidney injury (AKI). The objective of the work is to develop Nephrocast, a deep-learning model to predict next-day SCr in adult patients treated in the intensive care unit (ICU). Materials and Methods: Nephrocast was trained and validated, temporally and prospectively, using electronic health record data of adult patients admitted to the ICU in the University of California San Diego Health (UCSDH) between January 1, 2016 and June 22, 2024. The model features consisted of demographics, comorbidities, vital signs and laboratory measurements, and medications. Model performance was evaluated by mean absolute error (MAE) and root-mean-square error (RMSE) and compared against the prediction day's SCr as a reference. Results: A total of 28 191 encounters met the eligibility criteria, corresponding to 105 718 patient-days. The median (interquartile range [IQR]) MAE and RMSE in the internal test set were 0.09 (0.085-0.09) mg/dL and 0.15 (0.146-0.152) mg/dL, respectively. In the prospective validation, the MAE and RMSE were 0.09 mg/dL and 0.14 mg/dL, respectively. The model's performance was superior to the reference SCr. Discussion and Conclusion: Our model demonstrated good performance in predicting next-day SCr by leveraging clinical data routinely collected in the ICU. The model could aid clinicians in in identifying high-risk patients for AKI, predicting AKI trajectory, and informing the dosing of renally eliminated drugs.

Drug-Induced Acute Kidney Injury Risk Prediction Models.

BACKGROUND: Acute kidney injury (AKI) risk prediction models can predict AKI with short lead times and excellent model performance. However, these prediction models have not ascertained the etiology of the AKI. Drugs are an important contributor to AKI, and it is difficult to distinguish drug causes from other etiologies. SUMMARY: Clinical adjudication of AKI etiology can reduce misclassification associated with temporal relationships, since expert adjudicators are trained to assess an outcome in a consistent manner using standardized definitions. Drug-induced acute kidney injury (DI-AKI) varies by drug and is heterogeneous in onset and mechanisms, limiting a universal approach to risk prediction and necessitating expert review. DI-AKI models should be constructed using a high-quality prospective dataset to maximize model performance, internal and external validity. Predictor selection and engineering requires careful attention to unique issues arising from interactions such as drug dose and concentrations. Various statistical methods, such as least absolute shrinkage and selection operator regression or advanced machine learning techniques, may be applied to perform feature selection and capture trends and interactions between predictors. Finally, the model should be carefully evaluated by internal and external validation. KEY MESSAGES: The development of DI-AKI risk prediction models is needed to identify high-risk patients, identify new risk factors, formulate, and apply preventative strategies. DI-AKI risk prediction models require a well-defined dataset of clinically adjudicated cases to improve model performance, validity, and reduce the risk of misclassification.

Subtle Changes in Tacrolimus Levels Have an Impact on Early Donor-Specific Antibodies in Kidney Transplantation.

Introduction: The impact of each immunosuppressive agent on de novo donor-specific antibodies in kidney transplant recipients varies among extant literature. Project aims: Patterns in immunosuppression and the effects on incidence of de novo donor-specific antibodies were evaluated. Design: Adult kidney transplant recipients from 2017 to 2019 without preformed antibodies were sampled. Allograft function, de novo donor-specific antibodies, tacrolimus concentrations, duration of goal-dose antiproliferatives, and steroid doses were recorded. Outcomes included incidence of de novo donor-specific antibodies, and their relation to tacrolimus concentrations, time at goal-dose antiproliferatives, and steroid doses. Results: Recipients (N = 153) were followed for 1 year; all were crossmatch negative and received rabbit antithymocyte globulin induction. Sixteen (10%) recipients developed de novo donor-specific antibodies in a median of 31 days [interquartile range, IQR: 12-67 days], most were Class II antibodies (87.5%). Incidence of de novo donor-specific antibodies did not differ based on induction dosing. Tacrolimus levels in the first month were lower for patients with de novo donor-specific antibodies (8.8 ng/mL vs 10.4 ng/mL, P < .01). There was no difference in time on goal antiproliferative doses, but higher steroid doses (0.4 vs 0.3 mg/kg/d; P = .02) were noted in patients with antibodies. Steroid dosing was likely impacted by baseline risk factors. Conclusion: A significant association was found between lower tacrolimus concentrations early post-transplant and incidence of de novo donor-specific antibodies. This highlighted the importance of clinician attention to subtle changes in tacrolimus and the impact it can have on antibody risk in the early post-transplant period.

Sirolimus Long-Term Tolerability and Impact on Kidney Function in Lung Transplantation: A Single-Center Experience.

BACKGROUND: After lung transplant, 2 common complications are calcineurin inhibitor (CNI) induced nephrotoxicity and bronchiolitis obliterans syndrome. The objective of this study was to investigate the long-term effects of sirolimus conversion after lung transplantation. METHODS: This was a retrospective cohort study of patients who had undergone lung transplantation at a single center from June 2003 to December 2016. We compared patients converted to a sirolimus-based regimen to those maintained on our standard tacrolimus-based regimen. Kidney function, pulmonary function, and immunosuppression concentrations were compared between the groups. Additionally, indications, toxicity monitoring parameters, and discontinuation rates for sirolimus were collected. RESULTS: During the study period, 176 of the 205 patients who underwent lung transplants were converted to a sirolimus-containing regimen (86%). The most common reason for sirolimus initiation was impairment of kidney function or CNI-associated neurotoxicity. Sirolimus was initiated at a median of 150 days post-transplantation and continued for a medium time of 5.02 (2.27-7.85) years. Of those patients converted to sirolimus, 39 (22%) had sirolimus subsequently discontinued secondary to an adverse event. No difference in pulmonary function was found between the groups at 1- and 3-years post-transplantation. In the sirolimus group, the median estimated glomerular filtration rate improved by 8.6 mL/min/1.73 m2 at 3 months post-conversion (P < .001), which was maintained at both 1 and 3 years (P = .014 and .025, respectively). CONCLUSION: Sirolimus is a viable immunosuppressant option after lung transplant, which successfully allows for the reduction or withdrawal of the CNI, resulting in sustained improvement in kidney function.

Digital health and acute kidney injury: consensus report of the 27th Acute Disease Quality Initiative workgroup.

Acute kidney injury (AKI), which is a common complication of acute illnesses, affects the health of individuals in community, acute care and post-acute care settings. Although the recognition, prevention and management of AKI has advanced over the past decades, its incidence and related morbidity, mortality and health care burden remain overwhelming. The rapid growth of digital technologies has provided a new platform to improve patient care, and reports show demonstrable benefits in care processes and, in some instances, in patient outcomes. However, despite great progress, the potential benefits of using digital technology to manage AKI has not yet been fully explored or implemented in clinical practice. Digital health studies in AKI have shown variable evidence of benefits, and the digital divide means that access to digital technologies is not equitable. Upstream research and development costs, limited stakeholder participation and acceptance, and poor scalability of digital health solutions have hindered their widespread implementation and use. Here, we provide recommendations from the Acute Disease Quality Initiative consensus meeting, which involved experts in adult and paediatric nephrology, critical care, pharmacy and data science, at which the use of digital health for risk prediction, prevention, identification and management of AKI and its consequences was discussed.

Clinical Characteristics and Outcomes of Drug-Induced Acute Kidney Injury Cases.

Introduction: Drug-induced acute kidney injury (DI-AKI) is a frequent adverse event. The identification of DI-AKI is challenged by competing etiologies, clinical heterogeneity among patients, and a lack of accurate diagnostic tools. Our research aims to describe the clinical characteristics and predictive variables of DI-AKI. Methods: We analyzed data from the Drug-Induced Renal Injury Consortium (DIRECT) study (NCT02159209), an international, multicenter, observational cohort study of enriched clinically adjudicated DI-AKI cases. Cases met the primary inclusion criteria if the patient was exposed to at least 1 nephrotoxic drug for a minimum of 24 hours prior to AKI onset. Cases were clinically adjudicated, and inter-rater reliability (IRR) was measured using Krippendorff's alpha. Variables associated with DI-AKI were identified using L1 regularized multivariable logistic regression. Model performance was assessed using the area under the receiver operating characteristic curve (ROC AUC). Results: A total of 314 AKI cases met the eligibility criteria for this analysis, and 271 (86%) cases were adjudicated as DI-AKI. The majority of the AKI cases were recruited from the United States (68%). The most frequent causal nephrotoxic drugs were vancomycin (48.7%), nonsteroidal antiinflammatory drugs (18.2%), and piperacillin/tazobactam (17.8%). The IRR for DI-AKI adjudication was 0.309. The multivariable model identified age, vascular capacity, hyperglycemia, infections, pyuria, serum creatinine (SCr) trends, and contrast media as significant predictors of DI-AKI with good performance (ROC AUC 0.86). Conclusion: The identification of DI-AKI is challenging even with comprehensive adjudication by experienced nephrologists. Our analysis identified key clinical characteristics and outcomes of DI-AKI compared to other AKI etiologies.

Impact of Medication Reconciliation by a Dialysis Pharmacist.

Integrating a pharmacist into a hemodialysis unit significantly reduced medication discrepancies and medication-related problems over time.Medication reconciliation for the Centers for Medicare and Medicaid Services End-Stage Renal Disease Quality Incentive Program can be optimally performed by a dialysis pharmacist.

How to optimize drug delivery in renal replacement therapy.

Drug dosing in the setting of acute kidney injury (AKI) is complicated by several factors such as pharmacokinetic changes in renal failure, inaccuracy of renal estimating equations in this setting, lack of therapeutic drug monitoring capability for most drugs, and use of extracorporeal renal replacement. Pharmacokinetic changes include decreases in protein binding and drug metabolism. Renal estimating equations most often overestimate renal clearance in AKI. Additionally, it is well recognized that some drugs are significantly cleared by extracorporeal therapy. Patients with AKI are therefore at risk for adverse outcomes of drug therapy. It has been reported that approximately half of patients with reduced renal clearance receive drug doses that are 2.5 times higher than the recommended maximum dose. To ensure efficacy and prevent toxicity, therapeutic drug monitoring is highly recommended. However, in the absence of drug monitoring, adequate concentrations can only be inferred from clinical response. A clinician must weigh the risks and benefits of possible over-dosing or under-dosing based on the therapeutic index of the drug and the clinical situation. This article will review the important factors to consider for drug dosing in patients with AKI receiving continuous renal replacement therapy and sustained low-efficiency dialysis.

A Clinician's Guide to Dosing Analgesics, Anticonvulsants, and Psychotropic Medications in Continuous Renal Replacement Therapy.

Acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) is a common complication in critical illness and has a significant impact on pharmacokinetic factors determining drug exposure, including absorption, distribution, transport, metabolism, and clearance. In this review, we provide a practical guide to drug dosing considerations in critically ill patients undergoing CRRT, focusing on the most commonly used analgesic, anticonvulsant, and psychotropic medications in the clinical care of critically ill patients. A literature search was conducted to identify articles in which drug dosing was evaluated in adult patients receiving CRRT between the years 1980 and 2020. We included articles with pharmacokinetic/pharmacodynamic analyses and those that described medication clearance via CRRT. A summary of the data focused on practical pharmacokinetic and pharmacodynamic principles is presented, with recommendations for drug dosing of analgesics, anticonvulsants, and psychotropic medications. Pharmacokinetic and pharmacodynamic studies to guide drug dosing of analgesics, anticonvulsants, and psychotropic medications in critically ill patients receiving CRRT are sparse. Considering the widespread use of these medications, narrow therapeutic index of these drug classes, and risks of over- and underdosing, additional studies in patients receiving CRRT are needed to inform drug dosing.

Pharmacokinetics of Intraperitoneal Vancomycin and Amikacin in Automated Peritoneal Dialysis Patients With Peritonitis.

Objective: The study aimed to evaluate the vancomycin and amikacin concentrations in serum and dialysate for automatic peritoneal dialysis (APD) patients. Methods: A total of 558 serum and dialysate samples of 12 episodes of gram-positive and 18 episodes of gram-negative peritonitis were included to investigate the relationship between vancomycin and amikacin concentrations in serum and dialysate on the first and third days of treatment. Samples were analysed 30, 120 min, and 48 h after intraperitoneal administration of vancomycin in peritonitis caused by gram-positive agents and 30, 120 min, and 24 h after intraperitoneal administration of amikacin in peritonitis caused by gram-negative agents. Vancomycin was administered every 72 h and amikacin once a day. The target therapeutic concentration of amikacin was 25-35 mg/l at the peak moment and 4-8 mg/l at the trough moment; and after 48 h for vancomycin, 15-20 mg/l at the trough moment. Results: For peritonitis caused by gram-negative agents, at the peak moment, therapeutic levels of amikacin were reached in dialysate in 80.7% of patients with evolution to cure and in 50% of patients evaluated as non-cure (p = 0.05). At the trough moment, only 38% were in therapeutic concentrations in the dialysate in the cure group and 42.8% in the non-cure group (p = 1). Peak plasma concentrations were subtherapeutic in 98.4% of the samples in the cure group and in 100% of the non-cure group. At the trough moment, therapeutic concentrations were present in 74.4% of the cure group and 71.4% of the non-cure group (p = 1). Regarding vancomycin and among gram-positive agents, therapeutic levels were reached at the peak moment in 94% of the cure group and 6% of the non-cure group (p = 0.007). After 48 h, 56.8% of the cure group had a therapeutic serum concentration whereas for the non-cure group it was only 33.3% (p = 0.39). Conclusion: Despite a small sample size, we demonstrated peak dialysate amikacin level and peak serum vancomycin level correlates well with Gram-negative and Gram positve peritonitis cure, respectively. It is suggested to study the antibiotics pharmacodynamics for a better understanding of therapeutic success in a larger sample.