Hospital Mortality in the United States following Acute Kidney Injury

Runt-related transcription factor 1 (RUNX1) is a mediator of acute kidney injury

Treatment for acute kidney injury (AKI) is suboptimal. A better understanding of the pathogenesis of AKI may lead to new therapeutic approaches. Kidney transcriptomics of folic acid-induced AKI (FA-AKI) in mice identified Runx1 as the most upregulated RUNX family gene. We then examined the expression of RUNX1 in FA-AKI, in bacterial lipopolysaccharide (LPS)-induced cytokine storm-AKI (CS-AKI), and in human AKI. In cultured mouse tubule cells, we explored the expression and role of RUNX1 in response to the cytokine TWEAK or LPS. A chemical inhibitor of RUNX1 (Ro5-3335) was used in animal models of AKI to test its potential as a therapeutic target. RUNX1 overexpression in FA-AKI was validated at the mRNA and protein levels and localized mainly to tubule cell nuclei. CS-AKI also upregulated kidney RUNX1. Increased tubule and interstitial RUNX1 expression were also observed in human AKI. In cultured mouse tubule cells, the pro-inflammatory cytokine TWEAK and LPS increased RUNX1 and IL-6 expression. Mechanistically, RUNX1 bound to the Il6 gene promoter and RUNX1 targeting with the chemical inhibitor Ro5-3335, or a specific small interfering RNA (siRNA), prevented the TWEAK- and LPS-induced upregulation of IL6 through a RUNX1/NFκB1 p50 pathway. In vivo, preventive Ro5-3335 improved kidney function and reduced inflammation in FA-AKI and CS-AKI. However, Ro5-3335 administration after the insult only improved kidney function in CS-AKI. Kidney transcriptomics identified inflammatory genes and transcription factor mRNAs such as Yap1 and Trp53 as key targets of Ro5-3335 in CS-AKI. In conclusion, RUNX1 contributes to AKI by driving the expression of genes involved in inflammation and represents a novel therapeutic target in AKI. © 2024 The Author(s). The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

Ccl5+ Macrophages drive pro-inflammatory responses and neutrophil recruitment in sepsis-associated acute kidney injury

Sepsis leads to dysfunctional immune responses with multi-organ damage, and acute kidney injury (AKI) is a common complication of sepsis. To gain a deeper understanding of the specific underlying mechanisms of sepsis, we investigated the effects of specific macrophages on sepsis. To gain a deeper understanding of the specific underlying mechanisms of sepsis, we investigated the effects of specific macrophages on sepsis. Single-cell sequencing of a mouse model of endotoxemia revealed that sepsis is a common complication of sepsis. Single-cell sequencing of a mouse model of endotoxemia revealed that the emerging macrophage subpopulation Ccl5+ Mac was significantly pro-inflammatory, activating a large number of pathways activating a large number of pathways associated with immune response and inflammatory response, including IL6-JAK-STAT3 signaling, TGF-β signaling, and inflammatory response. Interestingly, we found that Ccl5+ Mac recruits neutrophil through CCL5-CCR1 ligand receptor pairs by cellular communication analysis thereby further affecting sepsis. We therefore hypothesize that this macrophage subpopulation is actively involved in the underlying molecular mechanisms of AKI. We therefore hypothesize that this macrophage subpopulation is actively involved in the underlying molecular mechanisms of AKI in sepsis and provide valuable insights.

Validation of Cefiderocol Package Insert Dosing Recommendation for Patients Receiving Continuous Renal Replacement Therapy: A Prospective Multicenter Pharmacokinetic Study

Background

Cefiderocol is the first antibiotic with effluent flow rate-based dosing recommendations outlined in the product label for patients receiving continuous renal replacement therapy (CRRT). We aimed to investigate the population pharmacokinetics of cefiderocol among patients receiving CRRT and validate these dosing recommendations.

Methods

A multicenter, prospective cefiderocol pharmacokinetic study among intensive care unit patients receiving CRRT was conducted (2022-2023). Blood sampling was performed at steady-state and cefiderocol concentrations were assayed by validated liquid chromatography-tandem mass spectrometry. Population pharmacokinetic analyses were conducted in Pmetrics using R software. The free time above the minimum inhibitory concentration (f T > MIC) and total daily area under the concentration time curve (AUCdaily) were calculated.

Results

Fourteen patients with effluent flow rates ranging from 2.1 to 5.1 L/h were enrolled. Cefiderocol concentrations best fitted a 2-compartment model. Mean ± standard deviation (SD) parameter estimates for clearance, central compartment volume, and intercompartment transfer constants (k12 and k21) were 3.5 ± 1.5 L/hour, 10.7 ± 8.4 L, 3.9 ± 1.8 hours-1, and 2.2 ± 2.2 hours-1, respectively. With simulations based on product label dosing recommendations, all patients achieved 100% fT > MIC up to MIC 8 mg/L with an AUCdaily (mean ± SD) of 1444 ± 423 mg × hour/L. Cefiderocol was well tolerated among the 14 patients.

Conclusions

The current package insert dosing recommendations resulted in pharmacodynamically optimized cefiderocol exposures. Cefiderocol concentrations exceeded relevant MIC breakpoints in all patients at each effluent flow rate, and AUCdaily was within the range observed in patients in the phase 3 clinical trials, suggestive of a safe and therapeutic drug profile.

Forecasting acute kidney injury and resource utilization in ICU patients using longitudinal, multimodal models

BACKGROUND

Advances in artificial intelligence (AI) have realized the potential of revolutionizing healthcare, such as predicting disease progression via longitudinal inspection of Electronic Health Records (EHRs) and lab tests from patients admitted to Intensive Care Units (ICU). Although substantial literature exists addressing broad subjects, including the prediction of mortality, length-of-stay, and readmission, studies focusing on forecasting Acute Kidney Injury (AKI), specifically dialysis anticipation like Continuous Renal Replacement Therapy (CRRT) are scarce. The technicality of how to implement AI remains elusive.

OBJECTIVE

This study aims to elucidate the important factors and methods that are required to develop effective predictive models of AKI and CRRT for patients admitted to ICU, using EHRs in the Medical Information Mart for Intensive Care (MIMIC) database.

METHODS

We conducted a comprehensive comparative analysis of established predictive models, considering both time-series measurements and clinical notes from MIMIC-IV databases. Subsequently, we proposed a novel multi-modal model which integrates embeddings of top-performing unimodal models, including Long Short-Term Memory (LSTM) and BioMedBERT, and leverages both unstructured clinical notes and structured time series measurements derived from EHRs to enable the early prediction of AKI and CRRT.

RESULTS

Our multimodal model achieved a lead time of at least 12 h ahead of clinical manifestation, with an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.888 for AKI and 0.997 for CRRT, as well as an Area Under the Precision Recall Curve (AUPRC) of 0.727 for AKI and 0.840 for CRRT, respectively, which significantly outperformed the baseline models. Additionally, we performed a SHapley Additive exPlanation (SHAP) analysis using the expected gradients algorithm, which highlighted important, previously underappreciated predictive features for AKI and CRRT.

CONCLUSION

Our study revealed the importance and the technicality of applying longitudinal, multimodal modeling to improve early prediction of AKI and CRRT, offering insights for timely interventions. The performance and interpretability of our model indicate its potential for further assessment towards clinical applications, to ultimately optimize AKI management and enhance patient outcomes.

The role of Testis-Specific Protein Y-encoded-Like 2 in kidney injury

Renal ischemia-reperfusion injury (IRI) is a major cause of acute kidney injury (AKI). Recent findings suggest that Testis-Specific Protein Y-encoded-Like 2 (TSPYL2) plays a fibrogenic role in diabetes-associated renal injury. However, the role of TSPYL2 in IRI-induced kidney damage is not entirely clear. In this study, we found that the expression of TSPYL2 was upregulated in a mouse model of AKI and in the hypoxia/reoxygenation (H/R) cell model. Knockdown of TSPYL2 attenuated kidney injury after IRI. More specifically, the knockdown of TSPYL2 or aminocarboxymuconate-semialdehyde decarboxylase (ACMSD) alleviated renal IRI-induced mitochondrial dysfunction and oxidative stress in vitro and in vivo. Further investigation showed that TSPYL2 regulated SREBP-2 acetylation by inhibiting SIRT1 and promoting p300 activity, thereby promoting the transcriptional activity of ACMSD. In conclusion, TSPYL2 was identified as a pivotal regulator of IRI-induced kidney damage by activating ACMSD, which may lead to NAD+ content and the damaging response in the kidney.

Forecasting Acute Kidney Injury and Resource Utilization in ICU patients using longitudinal, multimodal models

Background

Advances in artificial intelligence (AI) have realized the potential of revolutionizing healthcare, such as predicting disease progression via longitudinal inspection of Electronic Health Records (EHRs) and lab tests from patients admitted to Intensive Care Units (ICU). Although substantial literature exists addressing broad subjects, including the prediction of mortality, length-of-stay, and readmission, studies focusing on forecasting Acute Kidney Injury (AKI), specifically dialysis anticipation like Continuous Renal Replacement Therapy (CRRT) are scarce. The technicality of how to implement AI remains elusive.

Objective

This study aims to elucidate the important factors and methods that are required to develop effective predictive models of AKI and CRRT for patients admitted to ICU, using EHRs in the Medical Information Mart for Intensive Care (MIMIC) database.

Methods

We conducted a comprehensive comparative analysis of established predictive models, considering both time-series measurements and clinical notes from MIMIC-IV databases. Subsequently, we proposed a novel multi-modal model which integrates embeddings of top-performing unimodal models, including Long Short-Term Memory (LSTM) and BioMedBERT, and leverages both unstructured clinical notes and structured time series measurements derived from EHRs to enable the early prediction of AKI and CRRT.

Results

Our multimodal model achieved a lead time of at least 12 hours ahead of clinical manifestation, with an Area Under the Receiver Operating Characteristic Curve (AUROC) of 0.888 for AKI and 0.997 for CRRT, as well as an Area Under the Precision Recall Curve (AUPRC) of 0.727 for AKI and 0.840 for CRRT, respectively, which significantly outperformed the baseline models. Additionally, we performed a SHapley Additive exPlanation (SHAP) analysis using the expected gradients algorithm, which highlighted important, previously underappreciated predictive features for AKI and CRRT.

Conclusion

Our study revealed the importance and the technicality of applying longitudinal, multimodal modeling to improve early prediction of AKI and CRRT, offering insights for timely interventions. The performance and interpretability of our model indicate its potential for further assessment towards clinical applications, to ultimately optimize AKI management and enhance patient outcomes.

Global biomarkers trends in acute kidney injury: a bibliometric analysis

OBJECTIVES

Acute kidney injury (AKI) is a common global condition with high morbidity and mortality rates. Biomarkers can aid in the diagnosis, prediction, intervention, and outcome assessment of AKI. This study aimed to summarize the current research status and identify research hotspots for AKI biomarkers using bibliometric analysis.

METHODS

Relevant original English language articles were retrieved from the Science Citation Index Expanded of the Web of Science Core Collection database, from inception to 31 December 2022. Full records and related cited references from all the documents were collected and analyzed.

RESULTS

A total of 16368 authors from 3379 institutions in 83 countries/regions contributed to 2916 documents that were published in 712 academic journals. Annual publication output followed exponential growth since 2008. The United States, the University of Pittsburgh, and the American Journal of Physiology-Renal Physiology were the most productive countries, institutions, and journals in terms of research outputs, respectively. The area of interest has shifted from neutrophil gelatinase-associated lipocalin, cell cycle, and tubular damage toward sepsis and COVID-19. Apoptosis, inflammation, and chronic kidney disease have become popular in recent years, and studies on ferroptosis, machine learning, COVID-19, and renal fibrosis will be the focus of future research.

IMPLICATIONS

This bibliometric study suggests that future research on AKI biomarkers would focus on ferroptosis, renal fibrosis and COVID-19. Artificial intelligence, such as machine learning, maybe the most promising direction for the discovery and validation of AKI biomarkers.

Epidemiology data on the cost and outcomes associated with pediatric acute kidney injury

BACKGROUND

Hospitalized children with acute kidney injury (AKI) have not been extensively studied for clinical outcomes including hospital stay, the need for mechanical ventilation, mortality rates, and healthcare utilization. We hypothesize significant financial costs and increased morbidity and mortality associated with pediatric AKI.

METHODS

This is a retrospective study of pediatric patients (age ≤18 years) included in the Kids' Inpatient Database (KID) between January 1, 2016, and December 31, 2021. The results of the data analysis were utilized for comparative testing between the AKI and non-AKI cohorts.

RESULTS

The study included 4842 children [with AKI (n = 2424) and without AKI (n = 2418)]. The odds of mortality (p = 0.004) and mechanical ventilation (p < 0.001) were observed to be significantly higher among those with AKI as compared to those without AKI. Additionally, the median (IQR) duration of stay in the hospital (p < 0.001) and total cost (p < 0.001) were significantly higher among those with AKI vs. those without AKI.

CONCLUSIONS

AKI in children was associated with higher odds of mortality, longer duration of hospital stay, increased requirement of mechanical ventilation, and increased hospital expenditure. The scientific community can utilize this information to better understand the outcomes associated with this disease process in this patient population.

IMPACT

This article has thoroughly evaluated epidemiologic data associated with pediatric acute kidney injury (AKI) in hospitalized patients This study assesses mortality, hospital expenditure, and other factors to strengthen single-center and few multi-center studies and provides novel data regarding insurance and cost associated with pediatric AKI With increased knowledge of current epidemiology and risk factors, the scientific community can better understand prevention and outcomes in hospitalized children with AKI.

Temporal trends of post-contrast acute kidney injury in patients with intravenous administration of iodinated contrast medium

Little is known about whether preventative practices for post-contrast acute kidney injury (PC-AKI) recommended in guidelines have been adopted in clinical practice and translated into a lower incidence of PC-AKI. The aim of this study was to examine the yearly trends in the incidence of PC-AKI, and comorbidities and care practices associated with PC-AKI in hospitalized patients who received intravenous administration of iodinated contrast medium (ICM). Adult patients receiving intravenous ICM at the Second Xiangya Hospital of Central South University in China between 2015 and 2021 were included. Temporal trends in the incidence and risk factors for PC-AKI were evaluated using logistic regression analyses with adjustments for relevant variables. The incidence of PC-AKI has declined significantly from 5.3% in 2015 to 4.1% in 2021 (p < 0.001). This decreasing trend persisted after extensive multivariable adjustments. Of the comorbidities associated with PC-AKI, the proportion of patients with congestive heart failure or hypertension increased, while the proportion of patients older than 75 years, or with an estimated glomerular filtration rate (eGFR) < 30 mL/min/1.73 m2, diabetic nephropathy, or renal stone disease decreased. Among the care practices associated with PC-AKI, the proportion of patients using nephrotoxic drugs decreased, whereas the proportion of patients receiving intravenous fluids > 1000 mL on the day of ICM administration or using iso-osmolar ICM increased. In conclusion, a declining trend in PC-AKI incidence was observed in patients receiving intravenous ICM between 2015 and 2021, which may be related to increased awareness and efforts to prevent PC-AKI.

Renal, but not platelet or skin, extracellular vesicles decrease oxidative stress, enhance nascent peptide synthesis, and protect from ischemic renal injury

Acute kidney injury (AKI) is deadly and expensive, and specific, effective therapy remains a large unmet need. We have demonstrated the beneficial effects of transplanted adult tubular cells and extracellular vesicles (EVs; exosomes) derived from those renal cells on experimental ischemic AKI, even when administered after renal failure is established. To further examine the mechanisms of benefit with renal EVs, we tested the hypothesis that EVs from other epithelia or platelets (a rich source of EVs) might be protective, using a well-characterized ischemia-reperfusion model. When given after renal failure was present, renal EVs, but not those from skin or platelets, markedly improved renal function and histology. The differential effects allowed us to examine the mechanisms of benefit with renal EVs. We found significant decreases in oxidative stress postischemia in the renal EV-treated group with preservation of renal superoxide dismutase and catalase as well as increases in anti-inflammatory interleukin-10. In addition, we propose a novel mechanism of benefit: renal EVs enhanced nascent peptide synthesis following hypoxia in cells and in postischemic kidneys. Although EVs have been used therapeutically, these results serve as "proof of principle" to examine the mechanisms of injury and protection.NEW & NOTEWORTHY Acute kidney injury is common and deadly, yet the only approved treatment is dialysis. Thus, a better understanding of injury mechanisms and potential therapies is needed. We found that organ-specific, but not extrarenal, extracellular vesicles improved renal function and structure postischemia when given after renal failure occurred. Oxidative stress was decreased and anti-inflammatory interleukin-10 increased with renal, but not skin or platelet, exosomes. We also propose enhanced nascent peptide synthesis as a novel protective mechanism.

An Innovative Approach to Minimizing Downtime in Continuous Kidney Replacement Therapy

Continuous kidney replacement therapy (CKRT) is often utilized to stabilize patients with severe acute kidney injury associated with significant electrolyte abnormalities and/or oliguria and concomitant fluid accumulation. Circuit downtime may reduce daily treatment time and affect delivered doses of CKRT. Studies have found clotting to be the leading cause of downtime and underdosing, which are associated with negative treatment outcomes. The NxStage Cartridge Express with Speedswap (NxStage Medical, Inc.) was designed to minimize downtime by allowing filter priming to occur in parallel with ongoing CKRT and by permitting filter exchanges without the need to replace the entire cartridge. Data from pilot studies suggest that filter exchanges using this system interrupt treatment by an average of 4 minutes per exchange-a considerable reduction from traditional systems that require treatment to be discontinued while the filter is primed, which can take 30 minutes or more. In addition to increasing patient time on therapy, this system has the potential to reduce costs for patients who require a high number of filter changes, and reduce nursing labor and environmental impact (reduced plastic waste). Future studies should confirm whether patients at higher risk of clotted/clogged filters benefit from CKRT with a system designed for rapid filter changes.

Incidence, predictors, clinical outcomes, and economic burden of recurrent acute kidney injury: a retrospective cohort study

OBJECTIVE

This study aimed to assess the incidence, predictors, mortality, and economic outcomes of recurrent Acute kidney injury (AKI) in Jordan.

METHODS

This was a retrospective cohort study that included adult patients who were admitted with AKI to university hospitals in the country from 2010-2019. Recurrent episodes of AKI, laboratory data, baseline medication list, and death dates were retrieved from patient's medical records. The incidence rate of recurrent AKI was estimated. Predictors of recurrent AKI and mortality during the five years post-discharge was evaluated. Total admission charges were described and evaluated in total and by service provided.

RESULTS

Among 1162 AKI patients, 57 patients (4.9%) died during the index admission (first admission during the study period), and among the survivors, 220 patients were re-hospitalized with a recurrent AKI during five years of follow-up. Patients with higher discharge serum creatinine level (SCr) at index admission had higher odds of AKI recurrence (OR = 1.001). Patients who were on respiratory, antineoplastic, or anticoagulant medications were also more susceptible to recurrence; ORs were 1.69, 2.77, and 4.16, respectively. Patients who were elderly, with recurrent AKI episodes, or with a more extended hospital stay at index admission were more likely to die during the five years post discharge. The median charge of recurrent admissions was higher than the median charge of the index admissions; 1519.17 JOD ($2142.7) versus 1362.85 JOD ($1922.2), respectively.

CONCLUSIONS

Recurrent AKI is associated with increased mortality and health expenditures. Higher discharge SCr levels at index admission, and chronic comorbidities are associated with a higher likelihood of AKI recurrence.

Intensive Care Unit-Acquired Weakness in Patients With Acute Kidney Injury: A Contemporary Review

Acute kidney injury (AKI) and intensive care unit-acquired weakness (ICU-AW) are 2 frequent complications of critical illness that, until recently, have been considered unrelated processes. The adverse impact of AKI on ICU mortality is clear, but its relationship with muscle weakness-a major source of ICU morbidity-has not been fully elucidated. Furthermore, improving ICU survival rates have refocused the field of intensive care toward improving long-term functional outcomes of ICU survivors. We begin our review with the epidemiology of AKI in the ICU and of ICU-AW, highlighting emerging data suggesting that AKI and AKI treated with kidney replacement therapy (AKI-KRT) may independently contribute to the development of ICU-AW. We then delve into human and animal data exploring the pathophysiologic mechanisms linking AKI and acute KRT to muscle wasting, including altered amino acid and protein metabolism, inflammatory signaling, and deleterious removal of micronutrients by KRT. We next discuss the currently available interventions that may mitigate the risk of ICU-AW in patients with AKI and AKI-KRT. We conclude that additional studies are needed to better characterize the epidemiologic and pathophysiologic relationship between AKI, AKI-KRT, and ICU-AW and to prospectively test interventions to improve the long-term functional status and quality of life of AKI survivors.

Results of the 2018 Japan Society for Blood Purification in Critical Care survey: current status and outcomes

Background

The Japan Society for Blood Purification in Critical Care (JSBPCC) has reported survey results on blood purification therapy (BPT) for critically ill patients in 2005, 2009, and 2013. To clarify the current clinical status, including details of the modes used, treated diseases, and survival rate, we conducted this cohort study using data from the nationwide JSBPCC registry in 2018.

Methods

We analyzed data of 2371 patients who underwent BPT in the intensive care units of 43 facilities to investigate patient characteristics, disease severity, modes of BPTs, including the dose of continuous renal replacement therapy (CRRT) and hemofilters, treated diseases, and the survival rate for each disease. Disease severity was assessed using Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores.

Results

BPT was performed 2867 times in the 2371 patients. Mean APACHE II and SOFA scores were 23.5 ± 9.4 and 10.0 ± 4.4, respectively. The most frequently used mode of BPT was CRRT (67.4%), followed by intermittent renal replacement therapy (19.1%) and direct hemoperfusion with the polymyxin B-immobilized fiber column (7.3%). The most commonly used anticoagulant was nafamostat mesilate (78.6%). Among all patients, the 28-day survival rate was 61.7%. CRRT was the most commonly used mode for many diseases, including acute kidney injury (AKI), multiple organ failure (MOF), and sepsis. The survival rate decreased according to the severity of AKI (P = 0.001). The survival rate was significantly lower in patients with multiple organ failure (MOF) (34.6%) compared with acute lung injury (ALI) (48.0%) and sepsis (58.0%). Multivariate logistic regression analysis revealed that sepsis, ALI, acute liver failure, cardiovascular hypotension, central nervous system disorders, and higher APACHE II scores were significant predictors of higher 28-day mortality.

Conclusion

This large-scale cohort study revealed the current status of BPT in Japan. It was found that CRRT was the most frequently used mode for critically ill patients in Japan and that 28-day survival was lower in those with MOF or sepsis. Further investigations are required to clarify the efficacy of BPT for critically ill patients.

Trial Registration: UMIN000027678.

Seasonal variation in the detection rate and all-cause in-hospital mortality of AKI in China: A nationwide cohort study

Background

Acute kidney injury (AKI) is a severe clinical syndrome that places a massive burden on medical systems worldwide, yet the seasonality of AKI remains unexplored in China. The aim of this study was to describe the seasonal variation in the detection rate and all-cause in-hospital mortality of AKI in China based on a nationwide cohort study.

Methods

This was a retrospective cohort recruiting a national sample of 7,291 adult patients treated in hospitals in 22 provinces of mainland China during January or July 2013. AKI was defined according to the 2012 Kidney Disease Improving Global Outcomes AKI creatinine criteria or expanded criteria of increase or decrease in serum creatinine level of 50% during the hospital stay. The seasonal group was determined according to the corresponding admission date for each patient. The detection rate of AKI refers to the ratio of identified AKI cases to the total number of adult admissions from the same regional or seasonal group.

Results

Both the detection rate (2.31 vs. 2.08%, p = 0.001) and in-hospital mortality rate (13.3 vs. 10.7%, p = 0.001) of AKI were higher in winter than in summer. The patients with AKI detected in winter had higher proportions of prehistory diseases, cardiac or vascular kidney injury factors, and severe comorbidities than those in summer (all p < 0.05). In the multivariable analysis, winter was an independent risk factor for in-hospital mortality of patients with AKI [odds ratio (OR) = 1.22, 95% confidence interval (CI), 1.03-1.44, p = 0.02] after adjusting for demographic factors, medical history, comorbidity, and climatic confounders. Higher ambient temperature (OR = 0.91, 95% CI, 0.86-0.97, p = 0.002, per 10°C increase), higher relative humidity level (OR = 1.14, 95% CI, 1.04-1.25, p = 0.005, per 10% increase), and living in temperate continental region (OR = 2.18, 95% CI, 1.63-2.91, p < 0.001) were each independently associated with in-hospital mortality.

Conclusion

The detection rate and all-cause in-hospital mortality of AKI showed a winter predominance in patients with AKI in China. Winter appeared to be an independent risk factor for all-cause in-hospital mortality in patients with AKI. Environmental factors, including lower ambient temperature, higher relative humidity level, and living in temperate continental climatic regions, were each independently associated with increased risks of in-hospital mortality in patients with AKI.

Prediction of Mortality Risk After Ischemic Acute Kidney Injury With a Novel Prognostic Model: A Multivariable Prediction Model Development and Validation Study

Background and Objectives:

Acute kidney injury (AKI) that results from ischemia is a common clinical syndrome and correlates with high morbidity and mortality among hospitalized patients. However, a clinical tool to predict mortality risk of ischemic AKI is not available. In this study, we aimed to develop and validate models to predict the 30-day and 1-year mortality risk of hospitalized patients with ischemic AKI.

Methods

A total of 1,836 admissions with ischemic AKI were recruited from 277,898 inpatients admitted to three affiliated tertiary general hospitals of Central South University in China between January 2015 and December 2015. Patients in the final analysis were followed up for 1 year. Study patients were randomly divided in a 7:3 ratio to form the training cohort and validation cohort. Multivariable regression analyses were used for developing mortality prediction models.

Results

Hepatorenal syndrome, shock, central nervous system failure, Charlson comorbidity index (≥2 points), mechanical ventilation, renal function at discharge were independent risk factors for 30-day mortality after ischemic AKI, while malignancy, sepsis, heart failure, liver failure, Charlson comorbidity index (≥2 points), mechanical ventilation, and renal function at discharge were predictors for 1-year mortality. The area under the receiver operating characteristic curves (AUROCs) of 30-day prediction model were 0.878 (95% confidence interval (CI): 0.849-0.908) in the training cohort and 0.867 (95% CI: 0.820–0.913) in the validation cohort. The AUROCs of the 1-year mortality prediction in the training and validation cohort were 0.803 (95% CI: 0.772–0.834) and 0.788 (95% CI: 0.741–0.835), respectively.

Conclusion

Our easily applied prediction models can effectively identify individuals at high mortality risk within 30 days or 1 year in hospitalized patients with ischemic AKI. It can guide the optimal clinical management to minimize mortality after an episode of ischemic AKI.

Clinical Profile of Adult Patients Presenting With Renal Dysfunction to a Tertiary Hospital Emergency Department

Background Renal dysfunction is a potentially life-threatening condition that is commonly encountered in the emergency department (ED). This study aimed to describe the clinical profile of patients presenting with renal dysfunction to a tertiary-level hospital ED. Methods Medical records of patients presenting to the ED with renal dysfunction over a six-month period (July-December 2017) were reviewed. A descriptive analysis of the data was performed. Results Serum creatinine levels were measured in 7,442 (69.9%) of the 10,642 patients that were triaged into the ED. Of these, 208 (2.8%) were identified with renal dysfunction, of which 192 consented to study participation. The median age of study subjects was 49.5 (IQR 38.8-63.0) years; 108 (56.3%) were male; proteinuria on urine dipsticks was demonstrated in 108 (56.3%); 72 (37.5%) were HIV-positive; 66 (39.6%) required dialysis; 11 (5.7%) were admitted to the ICU; and 59 (30.7%) died prior to hospital discharge. More patients presented with acute kidney injury (AKI) (46.9%) compared to chronic kidney disease (CKD) (27.6%) and acute on chronic kidney disease (AoCKD) (25.5%). Sepsis was the most common precipitant of AKI (42.2%) and AoCKD (30.6%), while chronic hypertension (35.8%) and diabetes mellitus (34.0%) were the most common comorbidities in subjects with CKD. Conclusion Patients presenting to the ED with various risk factors and comorbidities, including HIV, sepsis, hypertension, and diabetes mellitus, may have underlying renal dysfunction. ED clinicians should therefore adopt a low threshold to screen for renal dysfunction in these patients.

In-Hospital and 1-Year Mortality Trends in a National Cohort of US Veterans with Acute Kidney Injury

BACKGROUND AND OBJECTIVES

AKI, a frequent complication among hospitalized patients, confers excess short- and long-term mortality. We sought to determine trends in in-hospital and 1-year mortality associated with AKI as defined by Kidney Disease Improving Global Outcomes consensus criteria.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study used data from the national Veterans Health Administration on all patients hospitalized from October 1, 2008 to September 31, 2017. AKI was defined by Kidney Disease Improving Global Outcomes serum creatinine criteria. In-hospital and 1-year mortality trends were analyzed in patients with and without AKI using Cox regression with year as a continuous variable.

RESULTS

We identified 1,688,457 patients and 2,689,093 hospitalizations across the study period. Among patients with AKI, 6% died in hospital, and 28% died within 1 year. In contrast, in-hospital and 1-year mortality rates were 0.8% and 14%, respectively, among non-AKI hospitalizations. During the study period, there was a slight decline in crude in-hospital AKI-associated mortality (hazard ratio, 0.98 per year; 95% confidence interval, 0.98 to 0.99) that was attenuated after accounting for patient demographics, comorbid conditions, and acute hospitalization characteristics (adjusted hazard ratio, 0.99 per year; 95% confidence interval, 0.99 to 1.00). This stable temporal trend in mortality persisted at 1 year (adjusted hazard ratio, 1.00 per year; 95% confidence interval, 0.99 to 1.00).

CONCLUSIONS

AKI associated mortality remains high, as greater than one in four patients with AKI died within 1 year of hospitalization. Over the past decade, there seems to have been no significant progress toward improving in-hospital or long-term AKI survivorship.

Sustained low efficiency dialysis is non-inferior to continuous renal replacement therapy in critically ill patients with acute kidney injury: A comparative meta-analysis

BACKGROUND

Critically ill adults with acute kidney injury (AKI) experience considerable morbidity and mortality. This systematic review aimed to compare the effectiveness of continuous renal replacement therapy (CCRT) versus sustained low efficiency dialysis (SLED) for individuals with AKI.

METHODS

We carried out a systematic search of existing databases according to standard methods and random effects models were used to generate the overall estimate. Heterogeneity coefficient was also calculated for each outcome measure.

RESULTS

Eleven studies having 1160 patients with AKI were included in the analyses. Meta-analysis results indicated that there was no statistically significant difference between SLED versus continuous renal replacement therapy (CRRT) in our primary outcomes, like mortality rate (rate ratio [RR] 0.67, 95% confidence interval [CI] 0.44-1.00; P = .05), renal recovery (RR 1.08, 95% CI 0.83-1.42; P = .56), and dialysis dependence (RR = 1.03, 95% CI 0.69-1.53; P = .89). Also, no statistically significant difference was observed for between SLED versus CRRT in the secondary outcomes: that is, length of intensive care unit stay (mean difference -0.16, 95% CI -0.56-0.22; P = .41) and fluid removal rate (mean difference -0.24, 95% CI -0.72-0.24; P = .32). The summary mean difference indicated that there was a significant difference in the serum phosphate clearance among patients treated with SLED and CRRT (mean difference -1.17, 95% CI -1.90 to -0.44, P = .002).

CONCLUSIONS

The analysis indicate that there was no major advantage of using continuous renal replacement compared with sustained low efficiency dialysis in hemodynamically unstable AKI patients. Both modalities are equally safe and effective in treating AKI among critically ill patients.

Continuous Renal Replacement Therapy Liberation and Outcomes of Critically Ill Patients With Acute Kidney Injury

OBJECTIVE

To examine the association between continuous renal replacement therapy (CRRT) liberation and clinical outcomes among patients with acute kidney injury (AKI) requiring CRRT.

METHODS

This single-center, retrospective cohort study included adult patients admitted to intensive care units with AKI and treated with CRRT from January 1, 2007, to May 4, 2018. Based on the survival and renal replacement therapy (RRT) status at 72 hours after the first CRRT liberation, we classified patients into liberated, reinstituted, and those who died. We observed patients for 90 days after CRRT initiation to compare the major adverse kidney events (MAKE₉₀).

RESULTS

Of 1135 patients with AKI, 228 (20%), 437 (39%), and 470 (41%) were assigned to liberated, reinstituted, and nonsurvival groups, respectively. The MAKE₉₀, mortality, and RRT independence rates of the cohort were 62% (707 cases), 59% (674 cases), and 40% (453 cases), respectively. Compared with reinstituted patients, the liberated group had a lower MAKE₉₀ (29% vs 39%; P=.009) and higher RRT independence rate (73% vs 65%; P=.04) on day 90, but without significant difference in 90-day mortality (26% vs 33%; P=.05). After adjustments for confounders, successful CRRT liberation was not associated with lower MAKE₉₀ (odds ratio, 0.71; 95% CI, 0.48 to 1.04; P=.08) but was independently associated with improved kidney recovery at 90-day follow-up (hazard ratio, 1.81; 95% CI, 1.41 to 2.32; P<.001).

CONCLUSION

Our study demonstrated a high occurrence of CRRT liberation failure and poor 90-day outcomes in a cohort of AKI patients treated with CRRT.

Expanded renal lymphatics improve recovery following kidney injury

Acute kidney injury (AKI) is a major cause of patient mortality and a major risk multiplier for the progression to chronic kidney disease (CKD). The mechanism of the AKI to CKD transition is complex but is likely mediated by the extent and length of the inflammatory response following the initial injury. Lymphatic vessels help to maintain tissue homeostasis through fluid, macromolecule, and immune modulation. Increased lymphatic growth, or lymphangiogenesis, often occurs during inflammation and plays a role in acute and chronic disease processes. What roles renal lymphatics and lymphangiogenesis play in AKI recovery and CKD progression remains largely unknown. To determine if the increased lymphatic density is protective in the response to kidney injury, we utilized a transgenic mouse model with inducible, kidney-specific overexpression of the lymphangiogenic protein vascular endothelial growth factor-D to expand renal lymphatics. "KidVD" mouse kidneys were injured using inducible podocyte apoptosis and proteinuria (POD-ATTAC) or bilateral ischemia reperfusion. In the acute injury phase of both models, KidVD mice demonstrated a similar loss of function measured by serum creatinine and glomerular filtration rate compared to their littermates. While the initial inflammatory response was similar, KidVD mice demonstrated a shift toward more CD4+ and fewer CD8+ T cells in the kidney. Reduced collagen deposition and improved functional recovery over time was also identified in KidVD mice. In KidVD-POD-ATTAC mice, an increased number of podocytes were counted at 28 days post-injury. These data demonstrate that increased lymphatic density prior to injury alters the injury recovery response and affords protection from CKD progression.

Acute kidney injury in hospitalized patients with COVID-19: A Portuguese cohort

INTRODUCTION

The incidence of acute kidney injury (AKI) in coronavirus disease 2019 (COVID-19) patients ranges from 0.5% to 35% and has been associated with worse prognosis. The purpose of this study was to evaluate the incidence, severity, duration, risk factors and prognosis of AKI in hospitalized patients with COVID-19.

METHODS

We conducted a retrospective single-center analysis of 192 hospitalized COVID-19 patients from March to May of 2020. AKI was diagnosed using the Kidney Disease Improving Global Outcome (KDIGO) classification based on serum creatinine (SCr) criteria. Persistent and transient AKI were defined according to the Acute Disease Quality Initiative (ADQI) workgroup definitions.

RESULTS

In this cohort of COVID-19 patients, 55.2% developed AKI (n=106). The majority of AKI patients had persistent AKI (n=64, 60.4%). Overall, in-hospital mortality was 18.2% (n=35) and was higher in AKI patients (28.3% vs. 5.9%, p<0.001, unadjusted OR 6.03 (2.22-16.37), p<0.001). In this multivariate analysis, older age (adjusted OR 1.07 (95% CI 1.02-1.11), p=0.004), lower Hb level (adjusted OR 0.78 (95% CI 0.60-0.98), p=0.035), duration of AKI (adjusted OR 7.34 for persistent AKI (95% CI 2.37-22.72), p=0.001) and severity of AKI (adjusted OR 2.65 per increase in KDIGO stage (95% CI 1.32-5.33), p=0.006) were independent predictors of mortality.

CONCLUSION

AKI was frequent in hospitalized patients with COVID-19. Persistent AKI and higher severity of AKI were independent predictors of in-hospital mortality.

Predicting successful continuous renal replacement therapy liberation in critically ill patients with acute kidney injury

PURPOSE

No standardized criteria for continuous renal replacement therapy (CRRT) liberation have been established. We sought to develop and internally validate prediction models for successful CRRT liberation in critically ill patients with acute kidney injury (AKI).

MATERIALS AND METHODS

This single-center, retrospective cohort study included adult patients admitted to intensive care units (ICUs) with AKI and treated with CRRT from January 1, 2007, to May 4, 2018, at a tertiary referral hospital. The cohort was randomly divided into derivation and validation sets. The outcomes were successful CRRT liberation, defined as renal replacement therapy (RRT)-free survival within 72 h after the liberation and hospital discharge. Multivariate logistic regression models were developed and internally validated.

RESULTS

Of 1135 AKI patients requiring CRRT, successful CRRT liberation and RRT-free survival at hospital discharge were observed in 228 (20%) and 395 (35%) individuals, respectively. The independent predictors included mean hourly urine output within 12 h before liberation, mean serum creatinine value within 24 h before liberation, cumulative fluid balance from ICU admission to liberation, CRRT duration before liberation, and the requirement of vasoactive agents within 24 h before liberation. The models demonstrated good discrimination (AUROC, 0.76 and 0.78; positive predictive value, 36% and 48%; negative predictive value, 92% and 94%; respectively) and calibration in the validation set.

CONCLUSIONS

These validated models could assist the decision-making related to the CRRT liberation in critically ill patients with AKI.

Immunomodulatory Effects of Mesenchymal Stem Cells on Drug-Induced Acute Kidney Injury

Drug-induced nephrotoxicity is an important and increasing cause of acute kidney injury (AKI), which accounts for approximately 20% of hospitalized patients. Previous reviews studies on immunity and AKI focused mainly on ischemia-reperfusion (IR), whereas no systematic review addressing drug-induced AKI and its related immune mechanisms is available. Recent studies have provided a deeper understanding on the mechanisms of drug-induced AKI, among which acute tubular interstitial injury induced by the breakdown of innate immunity was reported to play an important role. Emerging research on mesenchymal stem cell (MSC) therapy has revealed its potential as treatment for drug-induced AKI. MSCs can inhibit kidney damage by regulating the innate immune balance, promoting kidney repair, and preventing kidney fibrosis. However, it is important to note that there are various sources of MSCs, which impacts on the immunomodulatory ability of the cells. This review aims to address the immune pathogenesis of drug-induced AKI versus that of IR-induced AKI, and to explore the immunomodulatory effects and therapeutic potential of MSCs for drug-induced AKI.

Evaluating the Cost-Effectiveness of Celecoxib versus Ibuprofen and Naproxen in Patients with Osteoarthritis in United Arab Emirates Based on the PRECISION Trial

OBJECTIVE

Data on osteoarthritis patients from the PRECISION trial were used to evaluate the cost-effectiveness of celecoxib (100 mg twice daily) versus ibuprofen (600-800 mg three times daily) and naproxen (375-500 mg twice daily). The perspective was that of the United Arab Emirates (UAE) healthcare system.

METHODS

Discrete-state Markov model with monthly cycles, 30-month horizon, and 3% discount rate was constructed to assess incremental costs per quality adjusted life year (QALYs) gained from reduced incidence of three safety domains examined in PRECISION: renal, serious gastrointestinal (GI), and major adverse cardiovascular events (MACE). Costs for managing these toxicities were derived from Dubai Administrative Billing Claims (2018). Median monthly drug costs were derived from UAE Ministry of Health and Prevention's published prices ($26.98 celecoxib; $20.25 ibuprofen; $20.50 naproxen). Health utility and excess mortality associated with toxicities were sourced from the literature. The willingness-to-pay thresholds used were 1 and 3 GDP per capita ($40,000-$120,000).

RESULTS

The total average cost per patient was $812.88 for celecoxib, $775.26 for ibuprofen, and $731.17 for naproxen while cost components attributed to toxicities were lowest with celecoxib ($360.26, $438.31, and $388.60, respectively). Patients on celecoxib had more QALYs (1.339), compared with ibuprofen (1.335) and naproxen (1.337), resulting in an incremental cost-effectiveness ratio of $11,502/QALY gained for celecoxib versus ibuprofen and $39,779 for celecoxib versus naproxen. Probabilistic sensitivity analyses demonstrated celecoxib to be 81% cost-effective versus ibuprofen and 50% versus naproxen at $40,000/QALY. The most influential model parameters were MACE relative safety and drug costs.

CONCLUSION

From UAE third payer perspective, celecoxib is a long-term cost-effective treatment for osteoarthritis patients when compared with ibuprofen, and equally likely as naproxen to be cost-effective. With the expected increasing burden of chronic diseases in the Gulf region, study findings can inform decisions regarding the cost-effective pain management of osteoarthritis in UAE.

CLINICALTRIALSGOV REGISTRATION NUMBER

NCT00346216.

Impact of diabetes mellitus on short-term prognosis, length of stay, and costs in patients with acute kidney injury: A nationwide survey in China

Background

International data suggest that people with diabetes mellitus (DM) are at increased risk for worse acute kidney injury (AKI) outcomes; however, the data in China are limited. Therefore, this study aimed to describe the association of DM with short-term prognosis, length of stay, and expenditure in patients with AKI.

Methods

This study was based on the 2013 nationwide survey in China. According to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) and expanded criteria of AKI, 7604 patients with AKI were identified, and 1404 and 6200 patients were with and without DM, respectively. Clinical characteristics, outcomes, length of stay, and costs of these patients were compared. Multivariate regression analyses were conducted to evaluate the association of DM with mortality, failed renal recovery, length of stay, and costs.

Results

Patients with AKI and DM were older, had higher male preponderance (61.9%), presented with more comorbidities, and had higher serum creatinine levels compared with those without DM. An apparent increase in all-cause in-hospital mortality, length of stay, and costs was found in patients with DM. DM was not independently associated with failed renal recovery (adjusted OR (95%CI): 1.08 (0.94–1.25)) and in-hospital mortality (adjusted OR (95%): 1.16 (0.95–1.41)) in multivariate models. However, the diabetic status was positively associated with the length of stay (β = 0.06, p<0.05) and hospital expenditure (β = 0.10, p<0.01) in hospital after adjusting for possible confounders.

Conclusion

In hospitalized AKI patients, DM (vs. no DM) is independently associated with longer length of stay and greater costs, but is not associated with an increased risk for failed renal recovery and in-hospital mortality.

Advances in the Management of Renal Dysfunction in Patients With Cirrhosis

Renal dysfunction frequently develops in patients with advanced liver disease. Renal dysfunction in this setting is associated with adverse outcomes and an unfavorable prognosis. Hepatorenal syndrome (HRS), defined as worsening renal function in patients with advanced cirrhosis that can present either acutely (<3 months) or more indolently in the absence of other etiologies, remains a common cause of acute kidney injury. If reversal is not promptly achieved, rapid decline to mortality is common. Volume expansion and vasoconstrictors are the mainstays of therapy. Terlipressin, a vasopressin analogue licensed in several countries but not in the United States, is currently used for the treatment of HRS. Timely liver transplantation remains the only effective therapeutic option for a large group of patients with persistent renal dysfunction despite pharmacotherapy. In patients with underlying chronic renal dysfunction, simultaneous liver-kidney transplantation should be considered. The aim of this article is to present an overview of renal dysfunction in patients with cirrhosis, including diagnosis and management.

Protective Role of Sulodexide on Renal Injury Induced by Limb Ischemia-Reperfusion

Background

Though widely known as a potent antithrombin agent with protective effects on the kidney and other remote organs, it is currently ambiguous when it comes to sulodexide's function on ischemia-reperfusion (I/R) injury. With this research, we pursued to further explore how sulodexide exerts its influence on limb I/R injury, in which deleterious effects on the kidney were what we primarily focused on.

Methods

We randomized twenty-four C57BL/6 male rats into three groups, namely, sham operation group (control group), I/R group, and sulodexide pretreatment group. Hematoxylin and eosin staining was applied for discovery of renal histological changes. Serum creatinine (Cr) and serum urea nitrogen (BUN) were measured. Apoptotic parameters were detected by the TdT-mediated dUTP Nick-End Labeling method. To what extent and levels that antiapoptotic and proapoptotic proteins were expressed could be sensitively revealed by immunohistochemistry assay. Lipid peroxidation product propylene glycol and inflammatory factors were examined by enzyme-linked immunosorbent assay. Additionally, an extracorporeal hypoxia-reoxygenation (H/R) model of human renal proximal tubule epithelial HK2 cells was established. Our targets lay in cell proliferation and apoptosis, and we used western blotting to reflect apoptosis-related gene expression.

Results

The levels of serum BUN, Cr, and inflammatory factors in sulodexide-intervened rats manifested significant reduction when compared with the I/R group. Also, sulodexide could protect the kidney from histological changes and could effectively inhibit intraparenchymal apoptosis. Furthermore, adding 2 μl/mL or 5 μl/mL of sulodexide to H/R model cells in vitro gave rise to significant restoration of the degenerative proliferation capacity of the HK2 cells following H/R injury and late cellular apoptosis experienced dramatic reduction versus the H/R group. When treated with 5 μl/mL of sulodexide at a dose of 10 mg/kg, the levels of the antiapoptotic proteins were increased, while the proapoptotic proteins showed opposite trends. Notable escalation on antiapoptotic protein expression level, in contrast with the opposite trends exhibited in proapoptotic proteins, was observed with 5 μl/mL sulodexide pretreatment with the dosage being 10 mg/kg.

Conclusion

Sulodexide can protect against kidney damage caused by I/R injury of the lower limbs by enhancing cell proliferation, inhibiting apoptosis, reducing inflammatory reactions, and scavenging oxygen free radicals.

Acute kidney injury is an independent predictor of in-hospital mortality in a general medical ward: A retrospective study from a tertiary care centre in south India

Background & objectives:

Acute kidney injury (AKI) has been identified as an independent risk factor for mortality in intensive care units. This retrospective study was conducted to determine the effect of AKI on in-hospital mortality in a general medical ward of a tertiary care hospital and risk factors for mortality in patients with AKI.

Methods:

Demographic and clinical details, and outcome data were collected from case records of patients. In all hospitalized patients, factors associated with increased in-hospital mortality, such as AKI, inotrope requirement, mechanical ventilation and primary disease were compared between patients who died during their hospital stay and those who were discharged alive. Among the hospitalized patients, who had AKI, likely predictors of in-hospital mortality were compared between dead and alive patients at discharge. Factors that were significant in univariate analysis were tested by multivariate regression analysis to identify those that independently predicted poor outcomes.

Results:

Of the 1150 patients admitted in a general medical ward in a year, 220 patients were identified to have AKI. In-hospital mortality rate among patients with AKI was 19.09 per cent as compared to 1.8 per cent without AKI [adjusted odds ratio (OR) 5.7 (95% CI: 1.56-20.74)]. The presence of AKI was an independent risk factor for death, with an adjusted OR of 6.0 [95% CI: 1.67-21.6]. Among patients with AKI, the presence of haematological malignancy, adjusted OR 25.86 (95% CI: 1.81-369.58), requirement of inotrope, adjusted OR 126.5 (95% CI: 19.39-825.93) and serum creatinine at admission (P<0.001) were found to be independent predictors of death. The presence of underlying chronic kidney disease and hospital-acquired AKI were not found to have an association with mortality.

Interpretation & conclusions:

The study showed the in-hospital mortality rate among patients with AKI in a general medical ward was 19.09 per cent. The occurrence of AKI was an independent risk factor for death, with haematological malignancy, use of vasopressors and higher serum creatinine at admission, significantly associated with death among patients with AKI. Large prospective studies need to be done to better understand the outcomes in AKI and the ways to present and manage AKI.

Long-term outcomes following vehicle trauma related acute kidney injury requiring renal replacement therapy: a nationwide population study

Acute kidney injury (AKI) is a frequent complication of traumatic injury; however, long-term outcomes such as mortality and end-stage kidney disease (ESKD) have been rarely reported in this important patient population. We compared the long-term outcome of vehicle-traumatic and non-traumatic AKI requiring renal replacement therapy (AKI-RRT). This nationwide cohort study used data from the Taiwan National Health Insurance Research Database. Vehicle-trauma patients who were suffered from vehicle accidents developing AKI-RRT during hospitalization were identified, and matching non-traumatic AKI-RRT patients were identified between 2000 and 2010. The incidences of ESKD, 30-day, and long-term mortality were evaluated, and clinical and demographic associations with these outcomes were identified using Cox proportional hazards regression models. 546 vehicle-traumatic AKI-RRT patients, median age 47.6 years (interquartile range: 29.0–64.3) and 76.4% male, were identified. Compared to non-traumatic AKI-RRT, vehicle-traumatic AKI-RRT patients had longer length of stay in hospital [median (IQR):15 (5–34) days vs. 6 (3–11) days; p < 0.001). After propensity matching with non-traumatic AKI-RRT cases with similar demographic and clinical characteristics. Vehicle-traumatic AKI-RRT patients had lower rates of long-term mortality (adjusted hazard ratio (HR), 0.473; 95% CI, 0.392–0.571; p < 0.001), but similar rates of ESKD (HR, 1.166; 95% CI, 0.829–1.638; p = 0.377) and short-term risk of death (HR, 1.134; 95% CI, 0.894–1.438; p = 0.301) as non-traumatic AKI-RRT patients. In competing risk models that focused on ESKD, vehicle-traumatic AKI-RRT patients were associated with lower ESKD rates (HR, 0.552; 95% CI, 0.325–0.937; p = 0.028) than non-traumatic AKI-RRT patients. Despite severe injuries, vehicle-traumatic AKI-RRT patients had better long-term survival than non-traumatic AKI-RRT patients, but a similar risk of ESKD. Our results provide a better understanding of long-term outcomes after vehicle-traumatic AKI-RRT.

Changing epidemiology and outcomes of acute kidney injury in hospitalized patients with cirrhosis - a US population-based study

BACKGROUND & AIMS

Acute kidney injury (AKI) is a significant clinical event in cirrhosis yet contemporary population-based studies on the impact of AKI on hospitalized cirrhotics are lacking. We aimed to characterize longitudinal trends in incidence, healthcare burden and outcomes of hospitalized cirrhotics with and without AKI using a nationally representative dataset.

METHODS

Using the 2004-2016 National Inpatient Sample (NIS), admissions for cirrhosis with and without AKI were identified using ICD-9 and ICD-10 codes. Regression analysis was used to analyze the trends in hospitalizations, costs, length of stay and inpatient mortality. Descriptive statistics, simple and multivariable logistic regression were used to assess associations between individual characteristics, comorbidities, and cirrhosis complications with AKI and death.

RESULTS

In over 3.6 million admissions for cirrhosis, 22% had AKI. AKI admissions were more costly (median $13,127 [IQR $7,367-$24,891] vs. $8,079 [IQR $4,956-$13,693]) and longer (median 6 [IQR 3-11] days vs. 4 [IQR 2-7] days). Over time, AKI prevalence doubled from 15% in 2004 to 30% in 2016. CKD was independently and strongly associated with AKI (adjusted odds ratio 3.75; 95% CI 3.72-3.77). Importantly, AKI admissions were 3.75 times more likely to result in death (adjusted odds ratio 3.75; 95% CI 3.71-3.79) and presence of AKI increased risk of mortality in key subgroups of cirrhosis, such as those with infections and portal hypertension-related complications.

CONCLUSIONS

The prevalence of AKI is significantly increased among hospitalized cirrhotics. AKI substantially increases the healthcare burden associated with cirrhosis. Despite advances in cirrhosis care, a significant gap remains in outcomes between cirrhotics with and without AKI, suggesting that AKI continues to represent a major clinical challenge.

LAY SUMMARY

Sudden damage to the kidneys is becoming more common in people who are hospitalized and have cirrhosis. Despite advances in cirrhosis care, those with damage to the kidneys remain at higher risk of dying.

Proinflammatory P2Y14 receptor inhibition protects against ischemic acute kidney injury in mice

Ischemic acute kidney injury (AKI), a complication that frequently occurs in hospital settings, is often associated with hemodynamic compromise, sepsis, cardiac surgery, or exposure to nephrotoxins. Here, using a murine renal ischemia/reperfusion injury (IRI) model, we show that intercalated cells (ICs) rapidly adopted a proinflammatory phenotype after IRI. Wwe demonstrate that during the early phase of AKI either blockade of the proinflammatory P2Y14 receptor located on the apical membrane of ICs or ablation of the gene encoding the P2Y14 receptor in ICs (a) inhibited IRI-induced increase of chemokine expression in ICs, (b) reduced neutrophil and monocyte renal infiltration, (c) reduced the extent of kidney dysfunction, and (d) attenuated proximal tubule damage. These observations indicate that the P2Y14 receptor participates in the very first inflammatory steps associated with ischemic AKI. In addition, we show that the concentration of the P2Y14 receptor ligand UDP-glucose (UDP-Glc) was higher in urine samples from intensive care unit patients who developed AKI compared with patients without AKI. In particular, we observed a strong correlation between UDP-Glc concentration and the development of AKI in cardiac surgery patients. Our study identifies the UDP-Glc/P2Y14 receptor axis as a potential target for the prevention and/or attenuation of ischemic AKI.

Carbon monoxide: An emerging therapy for acute kidney injury

Treating acute kidney injury (AKI) represents an important unmet medical need both in terms of the seriousness of this medical problem and the number of patients. There is also a large untapped market opportunity in treating AKI. Over the years, there has been much effort in search of therapeutics with minimal success. However, over the same time period, new understanding of the underlying pathobiology and molecular mechanisms of kidney injury have undoubtedly helped the search for new therapeutics. Along this line, carbon monoxide (CO) has emerged as a promising therapeutic agent because of its demonstrated cytoprotective, and immunomodulatory effects. CO has also been shown to sensitize cancer, but not normal cells, to chemotherapy. This is particularly important in treating cisplatin-induced AKI, a common clinical problem that develops in patients receiving cisplatin therapies for a number of different solid organ malignancies. This review will examine and make the case that CO be developed into a therapeutic agent against AKI.

Association Between Early Recovery of Kidney Function After Acute Kidney Injury and Long-term Clinical Outcomes

IMPORTANCE

The severity of acute kidney injury (AKI) is usually determined based on the maximum serum creatinine concentration. However, the trajectory of kidney function recovery could be an additional important dimension of AKI severity.

OBJECTIVE

To assess whether the trajectory of kidney function recovery within 72 hours after AKI is associated with long-term risk of clinical outcomes.

DESIGN, SETTING, AND PARTICIPANTS

This prospective, multicenter cohort study enrolled 1538 adults with or without AKI 3 months after hospital discharge between December 1, 2009, and February 28, 2015. Statistical analyses were completed November 1, 2018. Participants with or without AKI were matched based on demographic characteristics, site, comorbidities, and prehospitalization estimated glomerular filtration rate. Participants with AKI were classified as having resolving or nonresolving AKI based on previously published definitions. Resolving AKI was defined as a decrease in serum creatinine concentration of 0.3 mg/dL or more or 25% or more from maximum in the first 72 hours after AKI diagnosis. Nonresolving AKI was defined as AKI not meeting the definition for resolving AKI.

MAIN OUTCOMES AND MEASURES

The primary outcome was a composite of major adverse kidney events (MAKE), defined as incident or progressive chronic kidney disease, long-term dialysis, or all-cause death during study follow-up.

RESULTS

Among 1538 participants (964 men; mean [SD] age, 64.6 [12.7] years), 769 (50%) had no AKI, 475 (31%) had a resolving AKI pattern, and 294 (19%) had a nonresolving AKI pattern. After a median follow-up of 4.7 years, the outcome of MAKE occurred in 550 (36%) of all participants. The adjusted hazard ratio for MAKE was higher for patients with resolving AKI (adjusted hazard ratio, 1.52; 95% CI, 1.01-2.29; P = .04) and those with nonresolving AKI (adjusted hazard ratio 2.30; 95% CI, 1.52-3.48; P < .001) compared with participants without AKI. Within the population of patients with AKI, nonresolving AKI was associated with a 51% greater risk of MAKE (95% CI, 22%-88%; P < .001) compared with resolving AKI. The higher risk of MAKE among patients with nonresolving AKI was explained by a higher risk of incident and progressive chronic kidney disease.

CONCLUSIONS AND RELEVANCE

This study suggests that the 72-hour period immediately after AKI distinguishes the risk of clinically important kidney-specific long-term outcomes. The identification of different AKI recovery patterns may improve patient risk stratification, facilitate prognostic enrichment in clinical trials, and enable recognition of patients who may benefit from nephrology consultation.

Carbon monoxide: An emerging therapy for acute kidney injury

Treating acute kidney injury (AKI) represents an important unmet medical need both in terms of the seriousness of this medical problem and the number of patients. There is also a large untapped market opportunity in treating AKI. Over the years, there has been much effort in search of therapeutics with minimal success. However, over the same time period, new understanding of the underlying pathobiology and molecular mechanisms of kidney injury have undoubtedly helped the search for new therapeutics. Along this line, carbon monoxide (CO) has emerged as a promising therapeutic agent because of its demonstrated cytoprotective, and immunomodulatory effects. CO has also been shown to sensitize cancer, but not normal cells, to chemotherapy. This is particularly important in treating cisplatin-induced AKI, a common clinical problem that develops in patients receiving cisplatin therapies for a number of different solid organ malignancies. This review will examine and make the case that CO be developed into a therapeutic agent against AKI.

Short, and long-term mortality among cardiac intensive care unit patients started on continuous renal replacement therapy

PURPOSE

Patients requiring continuous renal replacement therapy (CRRT) are at high risk of death. Predictors of hospital mortality and post-discharge survival in cardiac intensive care unit (CICU) patients requiring CRRT have not been reported.

MATERIALS AND METHODS

Retrospective review of 198 CICU patients undergoing CRRT from 2006 to 2015. Multivariable regression identified predictors of hospital mortality and Cox proportional-hazards identified predictors of post-discharge mortality among hospital survivors.

RESULTS

The indication for CRRT was volume overload in 129 (65%) and metabolic abnormalities in 76 (38%). 105 (53%) subjects died in hospital, with 22% dialysis-free hospital survival. Cardiogenic shock was present in 159 (80%) subjects; 150 (76%) subjects received vasopressors and 101 (51%) subjects required mechanical ventilation. Hospital mortality was similar in cardiogenic and non-cardiogenic causes of CICU admission. Predictors of hospital death included semi-quantitative RV function, Braden score, VIS, and PaO2/FIO2 ratio. Median post-discharge Kaplan-Meier survival was 1.9 years. Predictors of post-hospital death included age, VIS, diabetes, Braden score, semi-quantitative RV function, prior heart failure, and dialysis dependence. The indication for CRRT was not predictive of survival.

CONCLUSION

Mortality is high among CICU patients requiring CRRT, and is predicted by the Braden score, RV dysfunction, respiratory failure and vasopressor load.

Deficiency in SIRP-α cytoplasmic recruitment confers protection from acute kidney injury

Acute kidney injury (AKI) remains an important source of progressive chronic kidney injury. Loss of renal blood flow with subsequent restoration, termed ischemia reperfusion (IR), is a common cause of AKI. The cell surface receptor signal regulatory protein α (SIRP-α) is expressed on macrophages and limits inflammation and phagocytosis. SIRP-α has recently been found to have wider cell-based expression and play a role in renal IR. We have explored this in a genetic model of deficient SIRP-α signaling. Mice lacking SIRP-α cytoplasmic signaling (SIRP-α^mut) and wild-type (WT) littermate controls underwent renal ischemia and reperfusion. Chimeric mice transplanted with WT or SIRP-α^mut bone marrow were similarly challenged following engraftment. Molecular and immunohistochemical analysis of renal function, tissue damage, and key molecular targets was performed. SIRP-α^mut mice were protected from renal IR compared with WT animals, demonstrating improved serum creatinine, less histologic damage, reduced proinflammatory cytokine production, and diminished production of reactive oxygen species (ROS). Resistance to renal IR in SIRP-α^mut occurred alongside down-regulation of CD47 and thrombospondin-1, which are known to exert SIRP-α crosstalk and also promote IR. In chimeric mice, lack of SIRP-α signaling conferred protection to IR regardless of the genotype of circulating cells. Renal tubular epithelial cells from SIRP-α^mut mice produced fewer ROS and proinflammatory cytokines in vitro. These results identify parenchymal SIRP-α as an independent driver of IR-mediated AKI and a potential therapeutic target.-Ghimire, K., Chiba, T., Minhas, N., Meijles, D. N., Lu, B., O'Connell, P., Rogers, N. M. Deficiency in SIRP-α cytoplasmic recruitment confers protection from acute kidney injury.

Predictive Modeling of the Risk of Acute Kidney Injury in Critical Care: A Systematic Investigation of The Class Imbalance Problem

Acute Kidney Injury (AKI) in critical care is often a quickly-evolving clinical event with high morbidity and mortality. Early prediction of AKI risk in critical care setting can facilitate early interventions that are likely to provide ben- efit. Recently there have been some research on AKI prediction with patient Electronic Health Records (EHR). The class imbalance problem is encountered in such prediction setting where the number of AKI cases is usually much smaller than the controls. This study systematically investigates the impact of class imbalance on the performance of AKI prediction. We systematically investigate several class-balancing strategies to address class imbalance, includ- ing traditional statistical approaches and the proposed methods (case-control matching approach and individualized prediction approach). Our results show that the proposed class-balancing strategies can effectively improve the AKI prediction performance. Additionally, some important predictors (e.g., creatinine, chloride, and urine) for AKI can be found based on the proposed methods.

Urine podoplanin heralds the onset of ischemia-reperfusion injury of the kidney

Ischemia-reperfusion injury represents one of the most common causes of acute kidney injury, a serious and often deadly condition that affects up to 20% of all hospitalized patients in the United States. However, the current standard assay used universally for the diagnosis of acute kidney injury, serum creatinine, does not detect renal damage early in its course. Serendipitously, we found that the immunofluorescent signal of the constitutive podocyte marker podoplanin fades in the glomerulus and intensifies in the tubulointerstitial compartment of the kidney shortly after ischemia-reperfusion injury in 8- to 10-wk-old male C57Bl/6j mice. Therefore, we sought to define the appearance and course of the podoplanin-positive signal in the kidney after ischemia-reperfusion injury. The tubulointerstitial podoplanin-positive signal increased as early as 2 h but persisted for 7 days after ischemia-reperfusion injury. In addition, the strength of this tubulointerstitial signal was directly proportional to the severity of ischemia, and its location shifted from the tubules to interstitial cells over time. Finally, we detected podoplanin in the urine of mice after ischemia, and we observed that an increase in the urine podoplanin-to-creatinine ratio correlated strongly with the onset of renal ischemia-reperfusion injury. Our findings indicate that the measurement of urine podoplanin harbors promising potential for use as a novel biomarker for the early detection of ischemia-reperfusion injury of the kidney.

ADAMTS13 protects mice against renal ischemia-reperfusion injury by reducing inflammation and improving endothelial function

Acute kidney injury (AKI) is a serious condition without efficient therapeutic options. Recent studies have indicated that recombinant human a disintegrin and metalloprotease with thrombospondin motifs 13 (rhADAMTS13) provides protection against inflammation. Therefore, we hypothesized that ADAMTS13 might protect against AKI by reducing inflammation. Bilateral renal ischemia-reperfusion injury (I/R) was used as AKI models in this study. Prophylactic infusion of rhADAMTS13 was employed to investigate potential mechanisms of renal protection. Renal function, inflammation, and microvascular endothelial function were assessed after 24 h of reperfusion. Our results showed that I/R mice increased plasma von Willebrand factor levels but decreased ADAMTS13 expression. Administration of rhADAMTS13 to I/R mice recovered renal function, histological injury, and apoptosis. Renal inflammation was reduced by rhADAMTS13, accompanied with the downregulation of p38/extracellular signal-regulated protein kinase phosphorylation and cyclooxygenase-2 expression. rhADAMTS13 restored vasodilation in afferent arterioles in I/R mice. Furthermore, rhADAMTS13 treatment enhanced phosphorylation of Akt at Ser473 and eNOS at Ser1177. Administration of the Akt pathway inhibitor wortmannin reduced the protective effect of rhADAMTS13. Our conclusions are that treatment with rhADAMTS13 ameliorates renal I/R injury by reducing inflammation, tubular cell apoptosis, and improving microvascular endothelial dysfunction. rhADAMTS13 could be a promising strategy to treat AKI in clinical settings.

Inhibition of heparanase protects against chronic kidney dysfunction following ischemia/reperfusion injury

Renal ischemia/reperfusion (I/R) injury occurs in patients undergoing renal transplantation and with acute kidney injury and is responsible for the development of chronic allograft dysfunction as characterized by parenchymal alteration and fibrosis. Heparanase (HPSE), an endoglycosidase that regulates EMT and macrophage polarization, is an active player in the biological response triggered by ischemia/reperfusion (I/R) injury. I/R was induced in vivo by clamping left renal artery for 30 min in wt C57BL/6J mice. Animals were daily treated and untreated with Roneparstat (an inhibitor of HPSE) and sacrificed after 8 weeks. HPSE, fibrosis, EMT-markers, inflammation and oxidative stress were evaluated by biomolecular and histological methodologies together with the evaluation of renal histology and measurement of renal function parameters. 8 weeks after I/R HPSE was upregulated both in renal parenchyma and plasma and tissue specimens showed clear evidence of renal injury and fibrosis. The inhibition of HPSE with Roneparstat-restored histology and fibrosis level comparable with that of control. I/R-injured mice showed a significant increase of EMT, inflammation and oxidative stress markers but they were significantly reduced by treatment with Roneparstat. Finally, the inhibition of HPSE in vivo almost restored renal function as measured by BUN, plasma creatinine and albuminuria. The present study points out that HPSE is actively involved in the mechanisms that regulate the development of renal fibrosis arising in the transplanted organ as a consequence of ischemia/reperfusion damage. HPSE inhibition would therefore constitute a new pharmacological strategy to reduce acute kidney injury and to prevent the chronic pro-fibrotic damage induced by I/R.

Multi-perspective predictive modeling for acute kidney injury in general hospital populations using electronic medical records

Objectives

Acute kidney injury (AKI) in hospitalized patients puts them at much higher risk for developing future health problems such as chronic kidney disease, stroke, and heart disease. Accurate AKI prediction would allow timely prevention and intervention. However, current AKI prediction researches pay less attention to model building strategies that meet complex clinical application scenario. This study aims to build and evaluate AKI prediction models from multiple perspectives that reflect different clinical applications.

Materials and Methods

A retrospective cohort of 76 957 encounters and relevant clinical variables were extracted from a tertiary care, academic hospital electronic medical record (EMR) system between November 2007 and December 2016. Five machine learning methods were used to build prediction models. Prediction tasks from 4 clinical perspectives with different modeling and evaluation strategies were designed to build and evaluate the models.

Results

Experimental analysis of the AKI prediction models built from 4 different clinical perspectives suggest a realistic prediction performance in cross-validated area under the curve ranging from 0.720 to 0.764.

Discussion

Results show that models built at admission is effective for predicting AKI events in the next day; models built using data with a fixed lead time to AKI onset is still effective in the dynamic clinical application scenario in which each patient's lead time to AKI onset is different.

Conclusion

To our best knowledge, this is the first systematic study to explore multiple clinical perspectives in building predictive models for AKI in the general inpatient population to reflect real performance in clinical application.

Aristolochic acid I determine the phenotype and activation of macrophages in acute and chronic kidney disease

Acute and chronic kidney injuries are multifactorial traits that involve various risk factors. Experimental animal models are crucial to unravel important aspects of injury and its pathophysiological mechanisms. Translating knowledge obtained from experimental approaches into clinically useful information is difficult; therefore, significant attention needs to be paid to experimental procedures that mimic human disease. Herein, we compared aristolochic acid I (AAI) acute and chronic kidney injury model with unilateral ischemic-reperfusion injury (uIRI), cisplatin (CP)- or folic acid (FA)-induced renal damage. The administration of AAI showed significant changes in serum creatinine and BUN upon CKD. The number of neutrophils and macrophages were highly increased as well as AAI-induced CKD characterized by loss of tubular epithelial cells and fibrosis. The in vitro and in vivo data indicated that macrophages play an important role in the pathogenesis of AA-induced nephropathy (AAN) associated with an excessive macrophage accumulation and an alternative activated macrophage phenotype. Taken together, we conclude that AA-induced injury represents a suitable and relatively easy model to induce acute and chronic kidney injury. Moreover, our data indicate that this model is appropriate and superior to study detailed questions associated with renal macrophage phenotypes.

Repetitive ischemic injuries to the kidneys result in lymph node fibrosis and impaired healing

The contribution of the kidney-draining lymph node (KLN) to the pathogenesis of ischemia-reperfusion injury (IRI) of the kidney and its subsequent recovery has not been explored in depth. In addition, the mechanism by which repetitive IRI contributes to renal fibrosis remains poorly understood. Herein, we have found that IRI of the kidney is associated with expansion of high endothelial venules (HEVs) and activation of fibroblastic reticular cells (FRCs) in the KLN, as demonstrated by significant expansion in the extracellular matrix. The lymphotoxin α signaling pathway mediates activation of FRCs, and chronic treatment with lymphotoxin β receptor-immunoglobulin fusion protein (LTβr-Ig) resulted in marked alteration of the KLN as well as augmentation of renal fibrosis. Depletion of FRCs reduced T cell activation in the KLN and ameliorated renal injury in acute IRI. Repetitive renal IRI was associated with senescence of FRCs, fibrosis of the KLN, and renal scarring, which were ameliorated by FRC administration. Therefore, our study emphasizes the critical role of FRCs in both the initiation and repair phases of injury following IRI of the kidney.

Factors Affecting Inpatient Mortality in Elderly People with Acute Kidney Injury

Background

Acute Kidney Injury (AKI) is common in elderly people (EP). There is paucity of data on predictor of mortality in EP with AKI.

Objective

This study was done to know more about factors associated with inpatient mortality in EP with AKI.

Methods

We retrospectively reviewed medical records of patients aged 65 years or above hospitalized with a diagnosis of AKI at Aga Khan University Hospital, Karachi, between January 2005 and December 2010. Binary logistic regression models were constructed to identify factors associated with mortality in EP with AKI.

Results

431 patients had AKI, with 341 (79.1%) having stage I AKI, 56 (13%) having stage II AKI, and 34 (7.9%) having stage III AKI. Out of 431 patients, 142 (32.9%) died. Mortality increased with increasing severity of AKI. Mortality was 50% (17/34) in AKI stage III, 44.6% (25/56) in AKI stage II, and 29.3% (100/341) in AKI stage I. Factors associated with increased inpatients mortality were presence of stage III AKI (OR: 3.20, P = 0.04, 95% CI: 1.05-9.72), presence of oliguria (OR: 3.42, P = 0.006, 95% CI: 1.42-8.22), and need for vasopressors (OR: 6.90, P < 0.001, 95% CI: 2.42-19.65). Median bicarbonate 18 versus 17 between those who survived and those who died was associated with less mortality (OR: 0.94, P = 0.02, 95% CI: 0.89-0.99). History of hypertension (OR: 0.49, P = 0.03, 95% CI: 0.25-0.95) and high admission creatinine (OR: 0.68, P = 0.01, 95% CI: 0.50-0.91) were also associated with less mortality.

Conclusion

Mortality in EP increases with increasing severity of AKI. Presence of stage III AKI, oliguria, and hemodynamic instability needing vasopressor are associated with increased mortality. Increased median bicarbonate, presence of hypertension, and high admission creatinine were various factors associated with decreased inpatient mortality. Increasing age and need for dialysis did not increase mortality in elderly population.

Acute Kidney Injury in Critically Ill Patients with Sepsis: Clinical Characteristics and Outcomes

Objective: The objectives of this study were to examine the clinical profile of critically ill patients with septic acute kidney injury (AKI) and to investigate clinical characteristics associated with the outcome of patients. Methods: Data from 582 critically ill patients were collected and retrospectively reviewed. Patients were divided into two groups: without AKI development and with AKI development. Baseline characteristics, laboratory, and other clinical data were compared between these two groups, and correlations between the characteristics and AKI development were examined. Patients with AKI development were further divided into two groups according to the survival outcome, and variables associated with the outcome were determined. Results: AKI was developed in 54.12% (n = 315) of patients, and these patients had blood pressure, SOFA score, APACHE II score, GCS, and various blood chemistry and hematology characteristics significantly different from the patients without AKI. Demographic characteristics (e.g. age and weight) were comparable between the two groups of patients. Among the 315 patients with AKI, 136 of them died during the study period. Multivariate logistic regression analysis revealed that the outcome of patients was associated with lung infection, coagulation system dysfunction, staphylococcus aureus infection, and use of various treatments (epinephrine, norepinephrine, and the use of mechanical ventilation) after AKI development. Conclusion: AKI occurred in approximately half of the critically ill patients admitted to ICU. The site and type of infections, as well as the use of vasopressor agents, were associated with the outcome.

Sulodexide pretreatment attenuates renal ischemia-reperfusion injury in rats

Sulodexide is a potent antithrombin agent, however, whether it has beneficial effects on renal ischemia-reperfusion injury (IRI) remains unknown. In the present study, we assessed the therapeutic effects of sulodexide in renal IRI and tried to investigate the potential mechanism. One dose of sulodexide was injected intravenously in Sprague-Dawley rats 30 min before bilateral kidney ischemia for 45 min. The animals were sacrificed at 3h and 24h respectively. Our results showed that sulodexide pretreatment improved renal dysfunction and alleviated tubular pathological injury at 24h after reperfusion, which was accompanied with inhibition of oxidative stress, inflammation and cell apoptosis. Moreover, we noticed that antithrombin III (ATIII) was activated at 3h after reperfusion, which preceded the alleviation of renal injury. For in vitro study, hypoxia/reoxygenation (H/R) injury model for HK2 cells was carried out and apoptosis and reactive oxygen species (ROS) levels were evaluated after sulodexide pretreatment. Consistently, sulodexide pretreatment could reduce apoptosis and ROS level in HK2 cells under H/R injury. Taken together, sulodexide pretreatment might attenuate renal IRI through inhibition of inflammation, oxidative stress and apoptosis, and activation of ATIII.

Acute kidney injury in major abdominal surgery: incidence, risk factors, pathogenesis and outcomes

Acute kidney injury (AKI) is a common complication in patients undergoing major abdominal surgery. Various recent studies using modern standardized classifications for AKI reported a variable incidence of AKI after major abdominal surgery ranging from 3 to 35%. Several patient-related, procedure-related factors and postoperative complications were identified as risk factors for AKI in this setting. AKI following major abdominal surgery has been shown to be associated with poor short- and long-term outcomes. Herein, we provide a contemporary and critical review of AKI after major abdominal surgery focusing on its incidence, risk factors, pathogeny and outcomes.

Antithrombin III prevents progression of chronic kidney disease following experimental ischaemic-reperfusion injury

Acute kidney disease (AKI) leads to increased risk of progression to chronic kidney disease (CKD). Antithrombin III (ATIII) is a potent anticoagulant with anti-inflammatory properties, and we previously reported that insufficiencies of ATIII exacerbated renal ischaemia-reperfusion injury (IRI) in rats. In this study, we examined the characteristic of AKI-CKD transition in rats with two distinct AKI models. Based on our observation, left IRI plus right nephrectomy (NX-IRI) was used to determine whether ATIII had therapeutic effects in preventing CKD progression after AKI. It was observed that NX-IRI resulted in significant functional and histological damage at 5 weeks after NX-IRI compared with sham rats, which was mitigated by ATIII administration. Besides, we noticed that ATIII administration significantly reduced NX-IRI-induced interstitial fibrosis. Consistently, renal expression of collagen-1, α-smooth muscle actin and fibronectin were substantial diminished in ATIII-administered rats compared with un-treated NX-IRI rats. Furthermore, the beneficial effects of ATIII were accompanied with decreased M1-like macrophage recruitment and down-regulation of M1-like macrophage-dependent pro-inflammatory cytokines such as tumour necrosis factor α, inducible nitric oxide synthase and interleukin-1β, indicating that ATIII prevented AKI-CKD transition via inhibiting inflammation. Overall, ATIII shows potential as a therapeutic strategy for the prevention of CKD progression after AKI.