Improving outcomes in patients with Acute Kidney Injury: the impact of hospital based automated AKI alerts

Electronic Acute Kidney Injury Alert at the Brandenburg Medical School: Implementation and Follow-Up

INTRODUCTION

Acute kidney injury (AKI) substantially worsens the prognosis of hospitalized patients worldwide. In order to optimize early AKI recognition and therapeutic intervention, AKI alert systems have been implemented and evaluated in the past. Herein, we aimed to analyze outcome variables of AKI patients under the conditions of a de novo-established AKI alert system at the Brandenburg Hospital of the Brandenburg Medical School.

METHODS

Automated e-mail messages were generated and sent to the nephrologist with responsibility based on an electronic algorithm. The message was exclusively generated if one of the two first KDIGO criteria was fulfilled. During period 1, all alerts were ignored. During the second period, every alert was followed up, coupled with therapeutic management of respective individuals according to an AKI care bundle. Endpoints were in-hospital death, need for dialysis, and renal recovery.

RESULTS

In periods 1 and 2, 200 and 112 patients were included. In period 1, 150 out of 200 AKI alerts were identified as correct (75%); in the second period, 93 out of 112 AKI alerts were accepted as correct (83%) (p = 0.16). Kidney replacement therapy was initiated in 21 (14%) of all period 1 patients and in 32 (34.4%) of the period 2 patients (p = 0.017). In-hospital mortality of affected patients was 24 (16%) in period 1 and 21 (22.5%) in period 2 (p = 0.4). Restoration of kidney function was 69 (46%) in period 1 and 45 (48.3%) in period 2 (p = 0.71).

CONCLUSIONS

We finally conclude that an AKI alert system, as implemented and followed-up in our study, did not significantly improve clinically relevant endpoints in AKI patients. Potential weaknesses were the lack of documentation of the time between receiving the alert and patient contact, and physicians in responsibility were not particularly informed about the alert system.

Performance of urinary C-C motif chemokine ligand 14 for the prediction of persistent acute kidney injury: a systematic review and meta-analysis

BACKGROUND

Urinary C-C motif chemokine ligand 14 (CCL14) has been described as an effective marker for delayed recovery of acute kidney injury (AKI), yet its efficacy has been found to vary between different trials. The goal of this research was to assess the predictive performance of urinary CCL14 as a marker for persistent AKI.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched the PubMed, Embase, and Cochrane databases up to April 2023 for studies of adults (> 18 years) that reported the diagnostic performance of urinary CCL14. The sensitivity, specificity, number of events, true positive, and false positive results were extracted and evaluated. Hierarchical summary receiver operating characteristic curves (HSROCs) were used to summarize the pooled test performance, and the Grading of Recommendations, Assessment, Development and Evaluations criteria were used to appraise the quality of evidence.

RESULTS

We included six studies with 952 patients in this meta-analysis. The occurrence of persistent AKI among these patients was 39.6% (377/952). The pooled sensitivity and specificity results of urinary CCL14 in predicting persistent AKI were 0.81 (95% CI 0.72-0.87) and 0.71 (95% CI 0.53-0.84), respectively. The pooled positive likelihood ratio (LR) was 2.75 (95% CI 1.63-4.66), and the negative LR was 0.27 (95% CI 0.18-0.41). The HSROC with pooled diagnostic accuracy was 0.84.

CONCLUSION

Our results suggest that urinary CCL14 can be used as an effective marker for predicting persistent AKI.

Organ Protection by Caloric Restriction Depends on Activation of the De Novo NAD+ Synthesis Pathway

SIGNIFICANCE STATEMENT

AKI is a major clinical complication leading to high mortality, but intensive research over the past decades has not led to targeted preventive or therapeutic measures. In rodent models, caloric restriction (CR) and transient hypoxia significantly prevent AKI and a recent comparative transcriptome analysis of murine kidneys identified kynureninase (KYNU) as a shared downstream target. The present work shows that KYNU strongly contributes to CR-mediated protection as a key player in the de novo nicotinamide adenine dinucleotide biosynthesis pathway. Importantly, the link between CR and NAD+ biosynthesis could be recapitulated in a human cohort.

BACKGROUND

Clinical practice lacks strategies to treat AKI. Interestingly, preconditioning by hypoxia and caloric restriction (CR) is highly protective in rodent AKI models. However, the underlying molecular mechanisms of this process are unknown.

METHODS

Kynureninase (KYNU) knockout mice were generated by Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) and comparative transcriptome, proteome and metabolite analyses of murine kidneys pre- and post-ischemia-reperfusion injury in the context of CR or ad libitum diet were performed. In addition, acetyl-lysin enrichment and mass spectrometry were used to assess protein acetylation.

RESULTS

We identified KYNU as a downstream target of CR and show that KYNU strongly contributes to the protective effect of CR. The KYNU-dependent de novo nicotinamide adenine dinucleotide (NAD+) biosynthesis pathway is necessary for CR-associated maintenance of NAD+ levels. This finding is associated with reduced protein acetylation in CR-treated animals, specifically affecting enzymes in energy metabolism. Importantly, the effect of CR on de novo NAD+ biosynthesis pathway metabolites can be recapitulated in humans.

CONCLUSIONS

CR induces the de novo NAD+ synthesis pathway in the context of IRI and is essential for its full nephroprotective potential. Differential protein acetylation may be the molecular mechanism underlying the relationship of NAD+, CR, and nephroprotection.

A deep-learning model to continuously predict severe acute kidney injury based on urine output changes in critically ill patients

BACKGROUND

Acute Kidney Injury (AKI), a frequent complication of pateints in the Intensive Care Unit (ICU), is associated with a high mortality rate. Early prediction of AKI is essential in order to trigger the use of preventive care actions.

METHODS

The aim of this study was to ascertain the accuracy of two mathematical analysis models in obtaining a predictive score for AKI development. A deep learning model based on a urine output trends was compared with a logistic regression analysis for AKI prediction in stages 2 and 3 (defined as the simultaneous increase of serum creatinine and decrease of urine output, according to  the Acute Kidney Injury Network (AKIN) guidelines). Two retrospective datasets including 35,573 ICU patients were analyzed. Urine output data were used to train and test the logistic regression and the deep learning model.

RESULTS

The deep learning model defined an area under the curve (AUC) of 0.89 (± 0.01), sensitivity = 0.8 and specificity = 0.84, which was higher than the logistic regression analysis. The deep learning model was able to predict 88% of AKI cases more than 12 h before their onset: for every 6 patients identified as being at risk of AKI by the deep learning model, 5 experienced the event. On the contrary, for every 12 patients not considered to be at risk by the model, 2 developed AKI.

CONCLUSION

In conclusion, by using urine output trends, deep learning analysis was able to predict AKI episodes more than 12 h in advance, and with a higher accuracy than the classical urine output thresholds. We suggest that this algorithm could be integrated in the ICU setting to better manage, and potentially prevent, AKI episodes.

The Impact of Outpatient Laboratory Alerting Mechanisms in Patients with AKI

Background

AKI is an abrupt decrease in kidney function associated with significant morbidity and mortality. Electronic notifications of AKI have been utilized in patients who are hospitalized, but their efficacy in the outpatient setting is unclear.

Methods

We evaluated the effect of two outpatient interventions: an automated comment on increasing creatinine results (intervention I; 6 months; n=159) along with an email to the provider (intervention II; 3 months; n=105), compared with a control (baseline; 6 months; n=176). A comment was generated if a patient's creatinine increased by >0.5 mg/dl (previous creatinine ≤2.0 mg/dl) or by 50% (previous creatinine >2.0 mg/dl) within 180 days. Process measures included documentation of AKI and clinical actions. Clinical outcomes were defined as recovery from AKI within 7 days, prolonged AKI from 8 to 89 days, and progression to CKD with in 120 days.

Results

Providers were more likely to document AKI in interventions I (P=0.004; OR, 2.80; 95% CI, 1.38 to 5.67) and II (P=0.01; OR, 2.66; 95% CI, 1.21 to 5.81). Providers were also more likely to discontinue nephrotoxins in intervention II (P<0.001; OR, 4.88; 95% CI, 2.27 to 10.50). The median time to follow-up creatinine trended shorter among patients with AKI documented (21 versus 42 days; P=0.11). There were no significant differences in clinical outcomes.

Conclusions

An automated comment was associated with improved documented recognition of AKI and the additive intervention of an email alert was associated with increased discontinuation of nephrotoxins, but neither improved clinical outcomes. Translation of these findings into improved outcomes may require corresponding standardization of clinical practice protocols for managing AKI.

Modulation of Endocannabinoids by Caloric Restriction Is Conserved in Mice but Is Not Required for Protection from Acute Kidney Injury

Acute kidney injury (AKI) is a frequent and critical complication in the clinical setting. In rodents, AKI can be effectively prevented through caloric restriction (CR), which has also been shown to increase lifespan in many species. In Caenorhabditis elegans (C. elegans), longevity studies revealed that a marked CR-induced reduction of endocannabinoids may be a key mechanism. Thus, we hypothesized that regulation of endocannabinoids, particularly arachidonoyl ethanolamide (AEA), might also play a role in CR-mediated protection from renal ischemia-reperfusion injury (IRI) in mammals including humans. In male C57Bl6J mice, CR significantly reduced renal IRI and led to a significant decrease of AEA. Supplementation of AEA to near-normal serum concentrations by repetitive intraperitoneal administration in CR mice, however, did not abrogate the protective effect of CR. We also analyzed serum samples taken before and after CR from patients of three different pilot trials of dietary interventions. In contrast to mice and C. elegans, we detected an increase of AEA. We conclude that endocannabinoid levels in mice are modulated by CR, but CR-mediated renal protection does not depend on this effect. Moreover, our results indicate that modulation of endocannabinoids by CR in humans may differ fundamentally from the effects in animal models.

Admission Serum Bicarbonate Predicts Adverse Clinical Outcomes in Hospitalized Cirrhotic Patients

A low serum bicarbonate (SB) level is predictive of adverse outcomes in kidney injury, infection, and aging. Because the liver plays an important role in acid-base homeostasis and lactic acid metabolism, we speculated that such a relationship would exist for patients with cirrhosis. To assess the prognostic value of admission SB on adverse hospital outcomes, clinical characteristics were extracted and analyzed from a large electronic health record system. Patients were categorized based on admission SB (mEq/L) into 7 groups based on the reference range (22-25) into mildly (18-21), moderately (14-17), and severely (<14) decreased groups and mildly (26-29), moderately (30-33), and severely (>30) increased groups, and the relationship of SB category with the frequency of complications (acute kidney injury/hepatorenal syndrome, portosystemic encephalopathy, gastrointestinal bleeding, ascites, and spontaneous bacterial peritonitis) and hospital metrics (length of stay [LOS], admission to an intensive care unit [ICU], and mortality) was assessed. A total of 2,693 patients were analyzed. Mean SB was 22.9 ± 4.5 mEq/L. SB was within the normal range (22-25 mEq/L) in 1,072 (39.8%) patients, and 955 patients (36%) had a low SB. As the SB category decreased, the incidence of complications progressively increased (p < 0.001). Increased MELD-Na score and low serum albumin also correlated with frequency of complications (p < 0.001). As the SB category decreased, LOS, ICU admission, and mortality progressively increased (p < 0.001). On multivariate analysis, the association of decreased SB with higher odds of complications, LOS, ICU admission, and mortality persisted. Conclusion. Low admission SB in patients with cirrhosis is associated with cirrhotic complications, longer LOS, increased ICU admissions, and increased hospital mortality.

Acute pediatric peritoneal dialysis: impact of an opt-out model and adaptable methods in a hospital in Nigeria

BACKGROUND Despite efforts to scale peritoneal dialysis (PD) uptake, access is still limited in Sub-Saharan Africa, including Nigeria. Thus, this study evaluated access to PD, cost-effectiveness, complications, and in-hospital mortality rate following the adoption of a local opt-out model approach for all children with acute kidney injury (AKI) that required PD.  METHODS This work was a retrospective review of 33 children with AKI that required dialysis between December 2014 and November 2016. PD was carried out using locally adaptable consumables in place of commercially produced consumables. All patients that required renal replacement therapy (RRT) were offered an option to opt-out irrespective of their financial status. Patients’ relevant data were retrieved from the case notes and analyzed.  RESULTS The median age was 7 years (range 3–12). 23 patients (70%) were males. Of the 33 patients that required RRT, 29 had PD. The children had an access rate of 88% (95% CI = 76.77–99.03). The access rate was not related to gender (p = 1.000), age group (p = 0.240), or socioeconomic status (p = 0.755). Complications were pericatheter leakage of fluid (n = 7, 24%), catheter malfunction (n = 5, 17%), abdominal wall edema (n = 3, 10%), scrotal edema (n = 2, 7%), and peritonitis (n = 1, 3%). In-hospital mortality was 3/29 (10%; 95% CI = 2.2–27.3). Cost analysis revealed that the cost of consumables was reduced by 88.5%.  CONCLUSIONS An opt-out model with the use of locally adaptable consumables improved PD access (88%) with a low in-hospital mortality rate. 

Impact of electronic alerts for acute kidney injury on patient outcomes: interrupted time-series analysis of population cohort data

Background

Automated acute kidney injury (AKI) electronic alerts (e-alerts) are rule-based warnings triggered by changes in creatinine and are intended to facilitate earlier detection in AKI. We assessed the impact of the introduction in the Tayside region of UK in April 2015 of automated AKI e-alerts with an accompanying education programme.

Methods

Interrupted time-series analysis using segmented regression was performed involving all adults with AKI aged ≥18 years who had a serum creatinine measured between 1 April 2013 and 31 March 2017. Analysis evaluated associations of AKI e-alert introduction on rate and severity (Stages 2–3) of AKI as well as mortality and occupied hospital bed days per patient per month in the population with AKI.

Results

There were 32 320 episodes of AKI during the observation period. Implementation of e-alerts had no effect on the rate of any AKI [incidence rate ratio (IRR) 0.996, 95% confidence interval (CI) 0.991 to 1.001, P = 0.086] or on the rate of severe AKI (IRR 0.995, 95% CI 0.990 to 1.000, P = 0.061). Subgroup analysis found no impact on the rate or severity of AKI in hospital or in the community. Thirty-day mortality following AKI did not improve (IRR 0.998, 95% CI 0.987 to 1.009, P = 0.688). There was a slight reduction in occupied bed days (β-coefficient −0.059, 95% CI −0.094 to −0.025, P = 0.002).

Conclusions

Introduction of automated AKI e-alerts was not associated with a change in the rate, severity or mortality associated with AKI, but there was a small reduction in occupied hospital bed days.

Derivation and Validation of a Risk Prediction Model for Vancomycin-Associated Acute Kidney Injury in Chinese Population

Background

Vancomycin is the standard therapy for methicillin-resistant Staphylococcus aureus (MRSA) infection; however, nephrotoxicity happened with a high incidence of 15%~40%. Weighting the risk before receiving vancomycin treatment facilitates timely prevention of nephrotoxicity, but no standardized strategy exists for this purpose.

Methods

A retrospective cohort study was performed. A total of 524 hospitalized patients treated with vancomycin were included in this study. They were divided into derivation cohort (n=341) and externally validation cohort (n=183) according to their admission time. Using univariate and multivariable logistic regression, we identified potential predictors of vancomycin-associated acute kidney injury (AKI) and developed a risk score by plotting nomogram. The predictive performance of this novel risk score was assessed and validated by discrimination and calibration. Besides, the risk score was also compared with existing prediction models according to integrated discrimination index (IDI) and net reclassification index (NRI).

Results

The incidence of AKI was 16.1% (55/341) in the derivation cohort and 16.4% (30/183) in the validation cohort. Three factors (vancomycin serum trough concentration, piperacillin/tazobactam and furosemide) were determined as predictors for vancomycin-associated AKI. The established three-item risk score showed a comparable discrimination in both derivation cohort (AUC=0.793, 95% CI: 0.732–0.855) and validation cohort (AUC=0.788, 95% CI: 0.698–0.877). The risk score also demonstrated a good calibration in the derivation cohort (χ²=6.079, P=0.638>0.05) and validation cohort (χ²=5.665, P=0.686>0.05). Compared with prediction by C_min alone, this risk score significantly improved reclassification accuracy (IDI=0.050, 95% CI: 0.024–0.076, P<0.001, NRI=0.166, 95% CI: 0.044–0.289, P=0.007).

Conclusion

The established model in this study is a simplified three-item risk score, which provides a robust tool for the prediction of AKI after receiving vancomycin treatment.

Acute kidney injury demographics and outcomes: changes following introduction of electronic acute kidney injury alerts-an analysis of a national dataset

BACKGROUND

Electronic alerts for acute kidney injury (AKI) have been widely advocated. Our aim was to describe the changes in AKI demographics and outcomes following implementation of a national electronic AKI alert programme.

METHODS

A prospective national cohort study was undertaken to collect data on all cases of AKI in adult patients (≥18 years of age) between 1 April 2015 and 31 March 2019.

RESULTS

Over the period of data collection, there were 193 838 AKI episodes in a total of 132 599 patients. The lowest incidence of AKI was seen in the first year after implementation of electronic alerts. A 30-day mortality was highest in Year 1 and significantly lower in all subsequent years. A direct comparison of mortality in Years 1 and 4 demonstrated a significantly increased relative risk (RR) of death in Year 1: RR = 1.08 [95% confidence interval (CI) 1.054-1.114 P < 0.001]. This translates into a number needed to treat in Year 4 for one additional patient to survive of 69.5 (95% CI 51.7-106.2) when directly comparing the outcomes across the 2 years. The increase in the number of cases and improved outcomes was more pronounced in community-acquired AKI, and was associated with a significant increase in patient hospitalization.

CONCLUSIONS

This study represents the first large-scale dataset to clearly demonstrate that a national AKI alerting system which highlights AKI is associated with a change in both AKI demographics and patient outcomes.

Does nephrotoxicity develop less frequently when vancomycin is combined with imipenem-cilastatin than with meropenem? A comparative study

Introduction: Nephrotoxicity is a frequent complication of vancomycin therapy. Experimental studies in different animal species have demonstrated the attenuation of vancomycin-associated nephrotoxicity with cilastatin administration. This study aimed to evaluate if imipenem-cilastatin attenuates vancomycin-associated nephrotoxicity, in patients treated with combinations of vancomycin and carbapenems. Methods: This retrospective, propensity-score matched study was conducted at King Faisal Specialist Hospital and Research Centre, Riyadh and Jeddah. Nephrotoxicity was compared in patients who received imipenem-cilastatin + vancomycin or meropenem + vancomycin. Patients with no history of renal disease who received imipenem-cilastatin + vancomycin or meropenem + vancomycin for a minimum of 72 h, from 1 January 2017 to 31 December 2017, were included. Nephrotoxicity was defined according to the RIFLE criteria (Risk, Injury, Failure, Loss, End-stage renal disease) if sustained for least 72 h. Results: A total of 227 patients were included in the analysis, consisting of 121 patients in the imipenem-cilastatin + vancomycin group, and 106 patients in the meropenem + vancomycin group. In the unmatched data set the rate of nephrotoxicity was 8.2% in imipenem-cilastatin + vancomycin group and 20.7% in the meropenem + vancomycin group (p = .007). Logistic regression analysis showed that imipenem-cilastatin + vancomycin therapy was associated with a 56% lower rate of nephrotoxicity compared to meropenem + vancomycin therapy. Propensity-score matching resulted in rates of nephrotoxicity of 6.2% and 17.1% in the imipenem-cilastatin + vancomycin group and the meropenem + vancomycin groups, respectively (p = .034). Conclusion: Vancomycin-associated nephrotoxicity developed less frequently when vancomycin was combined with imipenem-cilastatin than when combined with meropenem.

EGFR drives the progression of AKI to CKD through HIPK2 overexpression

The molecular mechanism underlying the transition of acute kidney injury (AKI) to chronic kidney disease (CKD) induced by vancomycin (VAN) remains largely unknown.

Methods: The mice model of VAN drives AKI to CKD was developed to investigate the role and molecular mechanism of epidermal growth factor receptor (EGFR). The EGF receptor mutant (Wa-2) mice and gefitinib were used to inactivation of EGFR. The homeodomain interacting protein kinase 2 (HIPK2) siRNA was applied to silence of HIPK2. Human proximal tubular epithelial cells (HK-2) were used to explore the molecular regulation methanism of EGFR. ChIp analysis was used to investigate if STAT3 interaction with the promoter of HIPK2.

Results: A novel VAN-induced AKI mouse model was established for the first time. Moreover, the expression levels collagen I&IV, α-SMA, p-EGFR and the expression of HIPK2 proteins were upregulated in this model. Interestingly, AKI caused by VAN was markedly attenuated in waved-2 mice at the early stage, as evidenced by the suppression of renal dysfunction, renal cell apoptosis and caspase3 activation. In the latter stage, renal fibrosis and inflammation were significantly ameliorated in Wa-2 mice, accompanied by the downregulation of profibrotic molecules and F4/80. Besides, the expression levels of HIPK2 and p-STAT3 were suppressed in Wa-2 mice during VAN-induced transition of AKI to CKD. In addition, renal fibrosis and inflammation, profibrotic molecules, and EGFR/STAT3/HIPK2 signaling were ameliorated by gefitinib treatment after VAN-induced AKI. These results were consistent with the findings of Wa-2 mice. EGFR/STAT3 signaling mediated VAN-induced HIPK2 expression in HK-2 cells. ChIp analysis revealed that STAT3 directly bound to the promoter region of HIPK2. Finally, inhibition of HIPK2 attenuated the VAN drove the progression of AKI to CKD.

Conclusion: These data suggest that EGFR plays an important role in VAN-driven progression of AKI to CKD.

Urinary Neutrophil Gelatinase Associated Lipocalins (NGALs) predict acute kidney injury post liver transplant

BACKGROUND

Acute Kidney Injury, a common complication of liver transplant, is associated with a significant increase in the risk of morbidity, mortality and graft loss. Current diagnostic criteria leaves a delay in diagnosis allowing further potential irreversible damage. Early biomarkers of renal injury are of clinical importance and Neutrophil Gelatinase Associated Lipocalins (NGALs) and Syndecan-1 were investigated.

METHODS

AKI was defined according to the Acute Kidney Injury Network criteria. Urine and blood samples were collected pre-operatively, immediately post-op and 24 h post reperfusion to allow measurement of NGAL and Syndecan-1 levels.

RESULTS

13 of 27 patients developed an AKI. Patients who developed AKI had significantly higher peak transaminases. Urinary NGAL, plasma NGAL and Syndecan-1 levels were significantly elevated in all patients post reperfusion. Urinary NGAL levels immediately post-op were significantly higher in patients who developed an AKI than those that didn't [1319 ng/ml vs 46.56 ng/ml, p ≤ 0.001]. ROC curves were performed and urinary NGAL levels immediately post-op were an excellent biomarker for AKI with an area under the curve of 0.948 (0.847-1.00).

CONCLUSIONS

Urinary NGAL levels measured immediately post-op accurately predict the development of AKI and their incorporation into clinical practise could allow early protocols to be developed to treat post transplant AKI.

The proteome microenvironment determines the protective effect of preconditioning in cisplatin-induced acute kidney injury

Acute kidney injury (AKI) leads to significant morbidity and mortality; unfortunately, strategies to prevent or treat AKI are lacking. In recent years, several preconditioning protocols have been shown to be effective in inducing organ protection in rodent models. Here, we characterized two of these interventions-caloric restriction and hypoxic preconditioning-in a mouse model of cisplatin-induced AKI and investigated the underlying mechanisms by acquisition of multi-layered omic data (transcriptome, proteome, N-degradome) and functional parameters in the same animals. Both preconditioning protocols markedly ameliorated cisplatin-induced loss of kidney function, and caloric restriction also induced lipid synthesis. Bioinformatic analysis revealed mRNA-independent proteome alterations affecting the extracellular space, mitochondria, and transporters. Interestingly, our analyses revealed a strong dissociation of protein and RNA expression after cisplatin treatment that showed a strong correlation with the degree of damage. N-degradomic analysis revealed that most posttranscriptional changes were determined by arginine-specific proteolytic processing. This included a characteristic cisplatin-activated complement signature that was prevented by preconditioning. Amyloid and acute-phase proteins within the cortical parenchyma showed a similar response. Extensive analysis of disease-associated molecular patterns suggested that transcription-independent deposition of amyloid P-component serum protein may be a key component in the microenvironmental contribution to kidney damage. This proof-of-principle study provides new insights into the pathogenesis of cisplatin-induced AKI and the molecular mechanisms underlying organ protection by correlating phenotypic and multi-layered omics data.

Acute Kidney Injury Definition and Diagnosis: A Narrative Review

Acute kidney injury (AKI) is a complex syndrome characterized by a decrease in renal function and associated with numerous etiologies and pathophysiological mechanisms. It is a common diagnosis in hospitalized patients, with increasing incidence in recent decades, and associated with poorer short- and long-term outcomes and increased health care costs. Considering its impact on patient prognosis, research has focused on methods to assess patients at risk of developing AKI and diagnose subclinical AKI, as well as prevention and treatment strategies, for which an understanding of the epidemiology of AKI is crucial. In this review, we discuss the evolving definition and classification of AKI, and novel diagnostic methods.

MBD2 upregulates miR-301a-5p to induce kidney cell apoptosis during vancomycin-induced AKI

Despite DNA methylation occurred in acute kidney injury (AKI), how it influenced progression of AKI remains unclear. Methyl-CpG-binding domain protein 2 (MBD2), a protein readers of methylation, was used to analyze the impact of DNA methylation on vancomycin (VAN)-induced AKI. Here, in cultured human kidney tubular epithelial cells (HK-2), we show that knockdown of MBD2 by siRNA attenuated VAN-induced apoptosis, caspase activity, and the expression of BAX and cleaved caspase 3. Interestingly, knockdown of MBD2 by siRNA was associated with the suppression of miR-301a-5p. Mechanistic studies confirmed MBD2 binds to these methylated CpG elements of miR-301a-5p promoter, and then activates miR-301a-5p promoter by suppressing methylation. Furthermore, anti-miR-301a-5p significantly blocked VAN-induced apoptosis and caspase activity in HK-2 cells, which was accompanied by downregulation of p53, and upregulation of MITF, HDGF and MDM-4 together. The latter genes were further identified as target genes of miR-301a-5p, and silencing of MDM-4 promoted p53 accumulation. In vivo, mice with MBD2 knockout (MBD2-KO) were counteracted to VAN-induced AKI, indicated by the analysis of renal function, histology, apoptosis and inflammation. MBD2-KO also significantly suppressed the expression of miR-301a-5p, p53, BAX and cleaved caspase 3, and restored the expression of MDM-4, MITF and HDGF. Finally, in vivo inhibition of miR-301a-5p also ameliorated VAN-induced AKI. Together, these results show the novel MBD2/miR-301a-5p/MITF, HDGF and MDM-4/p53 pathway in VAN-induced AKI.

A whole system approach to improving mortality associated with acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is in the main managed by non-nephrologists, many who feel challenged by or lack awareness of the complexity that the renal element adds to their patients' care. National reports have raised major concerns about the quality of care and have predicted that mortality reductions of 30% are achievable with good medical practice.

AIM

This quality improvement project evaluated whether a whole system approach could improve outcomes for patients with AKI.

DESIGN AND METHODS

Quality improvement methodology was used to understand hospital patterns, processes and professional knowledge. Change concepts were developed which included management of patients at risk, staff education and awareness program, development of a patient specific electronic alert to prompt diagnosis, easy to remember care bundle (ABCDE-IT), dedicated outreach team and patient and family empowerment leaflet.

RESULTS

Statistical process control analysis was used to verify outcomes over time. A shift in the in-hospital mortality rate corresponded to a relative 23.2% reduction in mortality and was sustained over the next 33 months (P < 0.0001). The favourable shift in mortality was temporally distinct from the improved AKI detection rate. This timeframe corresponded to lying below the 99.8% lower confidence limit in comparison with all English acute trusts for comparative AKI specific SHMI/HSMR mortality rates. Length of stay also reduced shortly after onset of the project by 14.1% or 2.6 day reduction (P < 0.0001).

CONCLUSION

This project demonstrated that an integrated, whole-system approach is necessary to ensure sustained improvements in AKI mortality and length of stay.

Understanding Electronic AKI Alerts: Characterization by Definitional Rules

INTRODUCTION

Automated acute kidney injury (AKI) electronic alerts are based on comparing creatinine with historic results.

METHODS

We report the significance of AKI defined by 3 "rules" differing in the time period from which the baseline creatinine is obtained, and AKI with creatinine within the normal range.

RESULTS

A total of 47,090 incident episodes of AKI occurred between November 2013 and April 2016. Rule 1 (>26 μmol/l increase in creatinine within 48 hours) accounted for 9.6%. Rule 2 (≥50% increase in creatinine within previous 7 days) and rule 3 (≥50% creatinine increase from the median value of results within the last 8-365 days) accounted for 27.3% and 63.1%, respectively. Hospital-acquired AKI was predominantly identified by rules 1 and 2 (71.7%), and community-acquired AKI (86.3%) by rule 3. Stages 2 and 3 were detected by rules 2 and 3. Ninety-day mortality was higher in AKI rule 2 (32.4%) than rule 1 (28.3%, P < 0.001) and rule 3 (26.6%, P < 0.001). Nonrecovery of renal function (90 days) was lower for rule 1 (7.9%) than rule 2 (22.4%, P < 0.001) and rule 3 (16.5%, P < 0.001). We found that 19.2% of AKI occurred with creatinine values within normal range, in which mortality was lower than that in AKI detected by a creatinine value outside the reference range (22.6% vs. 29.6%, P < 0.001).

DISCUSSION

Rule 1 could only be invoked for stage 1 alerts and was associated with acute on chronic kidney disease acquired in hospital. Rule 2 was also associated with hospital-acquired AKI and had the highest mortality and nonrecovery. Rule 3 was the commonest cause of an alert and was associated with community-acquired AKI.

Electronic Alerts for Acute Kidney Injury

BACKGROUND

Acute kidney injury (AKI) often takes a complicated course if diagnosed late and undertreated. Electronic alerts that provide an early warning of AKI are intended to support treating physicians in making the diagnosis of AKI and treating it appropriately. The available evidence on the effects of such alert systems is inconsistent.

METHODS

We employed the PRISMA recommendations for systematic literature reviews to identify relevant articles in the PubMed, Scopus, and Web of Science databases. All of the studies that were retrieved were independently assessed by two of the authors with respect to the methods of computer-assisted electronic alert systems and their effects on process indicators and clinical endpoints.

RESULTS

16 studies with a total of 32 842 patients were identified. 8.5% of admitted patients had community-acquired or hospital-acquired AKI, with an in-hospital mortality of 22.8%. Fifteen electronic alert systems were in use throughout the participating hospitals. In 13 of 15 studies, alarm activation was accompanied by concrete treatment recommendations. A randomized controlled trial in which no such recommendations were given did not reveal any benefit of the alert system for the patients. In controlled but non-randomized trials, however, the provision of concrete treatment recommendations when the alert was activated led to more frequent implementation of diagnostic or therapeutic measures, less loss of renal function, lower in-hospital mortality, and lower mortality after discharge compared to control groups without an electronic alert for AKI.

CONCLUSION

Non-randomized controlled trials of electronic alerts for AKI that were coupled with treatment recommendations have yielded evidence of improved care processes and treatment outcomes for patients with AKI. This review is limited by the low number of randomized trials and the wide variety of endpoints used in the studies that were evaluated.

Review of vancomycin-induced renal toxicity: an update

In recent times the use of larger doses of vancomycin aimed at curbing the increasing incidence of resistant strains of Staphylococcus aureus has led to a wider report of acute kidney injury (AKI). Apart from biological plausibility, causality is implied by the predictive association of AKI with larger doses, longer duration, and graded plasma concentrations of vancomycin. AKI is more likely to occur with the concurrent use of nephrotoxic agents, and in critically ill patients who are susceptible to poor renal perfusion. Although most vancomycin-induced AKI cases are mild and therefore reversible, their occurrence may be associated with greater incidence of end-stage kidney disease and higher mortality rate. The strategy for its prevention includes adequate renal perfusion and therapeutic drug monitoring in high-risk individuals. In the near future, there is feasibility of renoprotective use of antioxidative substances in the delivery of vancomycin.