Acute Kidney Injury Classification for Critically Ill Cirrhotic Patients: A Comparison of the KDIGO, AKIN, and RIFLE Classifications

Evaluating outcomes in critically ill patients with undiagnosed acute kidney injury: a comparison of the incidence of physician-diagnosed vs KDIGO criteria-diagnosed acute kidney injury

Background

Acute kidney injury (AKI) independently predicts adverse outcomes, including morbidity, mortality, and prolonged hospital stays. Historically, inconsistent diagnostic criteria hindered the assessment of its prevalence. To address this, criteria such as Risk, Injury, Failure, Loss, and End-Stage Kidney Disease (RIFLE), Acute Kidney Injury Network (AKIN), and Kidney Disease: Improving Global Outcomes (KDIGO) were developed. Applying these criteria remains challenging, especially in critical care settings, leading to underdiagnosis and poorer outcomes.

Methods

This retrospective cohort study examined AKI incidence in critically ill patients by applying KDIGO criteria to charts of patients in the intensive care unit (ICU), comparing them to physician-diagnosed AKI. We examined the consequences for physician-undiagnosed AKI patients by analyzing variables such as mortality and hospital/ICU length of stay.

Results

Of the 1063 patients meeting KDIGO AKI criteria, physicians diagnosed 486 cases, missing 54% of AKI cases identified by KDIGO criteria. AKI was associated with longer hospital and ICU stays and higher mortality. Early stage AKI was particularly prone to underdiagnosis.

Discussion

This study reveals the underdiagnosis of AKI by ICU physicians. This significantly impacts patients with cardiovascular disease, complicating recovery from cardiac procedures and affecting both short-term and long-term outcomes. Enhancing early AKI surveillance offers an opportunity to optimize care and improve outcomes.

Mortality of Acute Kidney Injury in Cirrhosis: A Systematic Review and Meta-Analysis of Over 5 Million Patients Across Different Clinical Settings

BACKGROUND

Acute kidney injury (AKI) represents a commonly seen condition in the natural course of cirrhosis associated with unfavourable outcomes.

AIMS

To evaluate and compare the pooled mortality rates of patients with cirrhosis, with versus without AKI, across different clinical settings and diagnostic criteria.

METHODS

A systematic search of several databases was performed up to Oct 2023. Meta-analysis was performed using a generalised linear mixed model with a random effects model for all calculations.

RESULTS

A total of 59 studies comparing patients with cirrhosis, with and without AKI, were included in the meta-analysis, encompassing 1,153,193 individuals with AKI and 4,630,814 without AKI. AKI development predisposed to significantly higher short (in-hospital and 30-days)-, intermediate (90-days)- and long (1-year)-term mortality rates in both inpatients and outpatients. Remarkably, patients with AKI admitted to intensive care unit (ICU) or diagnosed with acute-on-chronic liver failure (ACLF) experienced the higher short-term mortality rates, reaching 76% [95% confidence interval (CI): 73%-79%] and 54% (95%CI: 33%-73%), respectively. AKI staging correlated with mortality risk, with higher stages indicating higher mortality rates, while the timing of AKI development, whether community-acquired or hospital-acquired, plays a crucial role in patient prognosis, with distinct mortality patterns observed in each group. The selection of diagnostic criteria for AKI may also impact its association with the short-term mortality risk.

CONCLUSIONS

AKI substantially affects the prognosis of patients with cirrhosis, especially those in ICU and/or with ACLF. Prognosis is also greatly influenced by the AKI stage, timing of onset and diagnostic criteria.

Incidence and risk factors of acute kidney injury in cirrhosis: a systematic review and meta-analysis of 5,202,232 outpatients, inpatients, and ICU-admitted patients

INTRODUCTION

Acute kidney injury (AKI) is a commonly seen condition in the natural course of cirrhosis. The aim of this study was to evaluate the pooled incidence and risk factors of AKI in different clinical stages and situations in patients with cirrhosis.

METHODS

Search was conducted on 13 December 2023 across MEDLINE (PubMed), Embase, and Cochrane databases. Meta-analysis was performed using a generalized linear mixed model.

RESULTS

In total, 73 studies with 5,202,232 patients were finally enrolled in the meta-analysis. AKI commonly occurs among hospitalized cirrhotics experiencing any decompensation event (29%) as well as among stable outpatients (28%) throughout a 1-year follow-up period. On admission, patients with infection or sepsis/septic shock had the highest AKI rate (47%), followed by those with hepatic encephalopathy (41%). Furthermore, the severity of liver disease proved to be a substantial driver for AKI development, while patients at intensive care unit had the greatest AKI incidence (61%).

CONCLUSIONS

Both hospitalized patients and stable outpatients with cirrhosis exhibited an elevated susceptibility to AKI. Patients at intensive care unit and those with severe liver disease, infection, sepsis/septic shock, hepatic encephalopathy, or acute on chronic liver failure upon admission are at higher risk for AKI.

TRIAL REGISTRATION

PROSPERO, registered 09/12/23, CRD42023487736.

Development and validation of a nomogram for predicting in-hospital death in cirrhotic patients with acute kidney injury

BACKGROUND

The purpose of this study was to develop a nomogram for predicting in-hospital mortality in cirrhotic patients with acute kidney injury (AKI) in order to identify patients with a high risk of in-hospital death early.

METHODS

This study collected data on cirrhotic patients with AKI from 2008 to 2019 using the Medical Information Mart for Intensive Care IV. Multivariate logistic regression was used to identify confounding factors related to in-hospital mortality, which were then integrated into the nomogram. The concordance index (C-Index) was used to evaluate the accuracy of the model predictions. The area under the curve (AUC) and decision curve analysis (DCA) was used to assess the predictive performance and clinical utility of the nomogram.

RESULTS

The final study population included 886 cirrhotic patients with AKI, and 264 (29.8%) died in the hospital. After multivariate logistic regression, age, gender, cerebrovascular disease, heart rate, respiration rate, temperature, oxygen saturation, hemoglobin, blood urea nitrogen, serum creatinine, international normalized ratio, bilirubin, urine volume, and sequential organ failure assessment score were predictive factors of in-hospital mortality. In addition, the nomogram showed good accuracy in estimating the in-hospital mortality of patients. The calibration plots showed the best agreement with the actual presence of in-hospital mortality in patients. In addition, the AUC and DCA curves showed that the nomogram has good prediction accuracy and clinical value.

CONCLUSIONS

We have created a prognostic nomogram for predicting in-hospital death in cirrhotic patients with AKI, which may facilitate timely intervention to improve prognosis in these patients.

Preoperative serum selenium predicts acute kidney injury after adult cardiac surgery

BACKGROUND

The relationship between serum selenium (Se) and acute kidney injury after adult cardiac surgery (CSA-AKI) remains controversial. This study aimed to investigate the association of preoperative Se level with incident CSA-AKI.

METHOD AND RESULTS

A retrospective cohort study was conducted on patients who underwent cardiac surgery. The primary outcome was incident CSA-AKI. Multivariable logistic regression models and natural cubic splines were used to estimate the association of Se levels and primary outcome. A total of 453 patient with a mean age of 62.97 years were included. Among all patients, 159 (35.1%) incident cases of CSA-AKI were identified. The level of preoperative Se concentration in patients with CSA-AKI was significant lower than that in patients without CSA-AKI. The higher preoperative Se level was significantly associated with decreased risk of CSA-AKI (adjusted OR 0.91, 95% CI: 0.87-0.99). Dose-response relationship curve revealed a nearly L-shape correlation between serum Se selenium levels and incident CSA-AKI.

CONCLUSION

Our study suggested that a higher level of serum Se was significantly associated with lower risk of CSA-AKI. Further prospective studies are needed to clarify the causal relationship between serum Se level and incident CSA-AKI.

Impact of acute kidney injury on the risk of mortality in patients with cirrhosis: a systematic review and meta-analysis

Objective

To compare the risk of mortality in patients with cirrhosis with and without the associated acute kidney injury (AKI).

Methods

We performed a systematic search in the PubMed, Embase, and Scopus databases for observational studies that were done on patients with cirrhosis. Eligible studies reported AKI in patients with cirrhosis and compared mortality among patients with and without AKI. We used a random-effects model, using STATA version 16.0, for deriving pooled effect sizes that were reported as odds ratio (OR) with 95% confidence intervals (CIs).

Results

Thirty-two studies were included. In patients with cirrhosis, AKI was significantly associated with higher in-hospital mortality (OR 5.92), and mortality at 30 days (OR 4.78), 90 days (OR 4.34), and at 1 year follow-up (OR 4.82) compared to patients without AKI.

Conclusions

AKI is associated with an increased risk of mortality in patients with cirrhosis. Careful monitoring to identify the development of AKI and early prompt management is necessary.

Incidence and Risk Factors of Colistin-Induced Nephrotoxicity Associated with The International Consensus Guidelines for the Optimal Use of the Polymyxins: A Retrospective Study in a Tertiary Care Hospital, Saudi Arabia

Background: Colistin is an effective therapy against multidrug-resistant gram-negative bacteria. However, nephrotoxicity is a major issue with its use. Objective: We aimed to evaluate the incidence and the potential risk factors of nephrotoxicity in colistin-treated patients. Methods: A retrospective cohort study was conducted. All adult patients aged 18 years and older who received colistin for ≥72 h were included in the study, while end-stage kidney disease patients requiring dialysis or had renal transplants were excluded. The incidence and severity of acute kidney injury (AKI) were assessed based on the Kidney Disease Improving Global Outcomes (KDIGO). Result: Out of 128 patients who received colistin, 51.56% of them have experienced AKI. The incidence was increased among oldest patients (above 80) and those who did not receive the appropriate dose (p-value = 0.0003). In addition, the median time until the AKI occurred was 10 days after receiving the colistin treatment. Rates of AKI in patients with previous AKI (71.7%) were three times higher than patients who did not previously experience AKI (HR = 2.97, 95% CI [1.8-4.8]). Conclusions: Nephrotoxicity is a significant issue among patients who receive colistin in the hospital, especially among older patients and those who did not receive the appropriate dose. As a result, healthcare providers should play a major role in colistin dosing, especially among the older adult population.

Modelling kidney outcomes based on MELD eras - impact of MELD score in renal endpoints after liver transplantation

Background

Acute kidney injury is a common complication in solid organ transplants, notably liver transplantation. The MELD is a score validated to predict mortality of cirrhotic patients, which is also used for organ allocation, however the influence of this allocation criteria on AKI incidence and mortality after liver transplantation is still uncertain.

Methods

This is a retrospective single center study of a cohort of patients submitted to liver transplant in a tertiary Brazilian hospital: Jan/2002 to Dec/2013, divided in two groups, before and after MELD implementation (pre-MELD and post MELD). We evaluate the differences in AKI based on KDIGO stages and mortality rates between the two groups.

Results

Eight hundred seventy-four patients were included, 408 in pre-MELD and 466 in the post MELD era. The proportion of patients that developed AKI was lower in the post MELD era (p 0.04), although renal replacement therapy requirement was more frequent in this group (p < 0.01). Overall mortality rate at 28, 90 and 365 days was respectively 7%, 11% and 15%. The 1-year mortality rate was lower in the post MELD era (20% vs. 11%, p < 0.01). AKI incidence was 50% lower in the post MELD era even when adjusted for clinically relevant covariates (p < 0.01).

Conclusion

Liver transplants performed in the post MELD era had a lower incidence of AKI, although there were more cases requiring dialysis. 1-year mortality was lower in the post MELD era, suggesting that patient care was improved during this period.

Development and validation of a nomogram for predicting overall survival in cirrhotic patients with acute kidney injury

BACKGROUND

Acute kidney injury (AKI) is a common and severe complication in patients with cirrhosis, and is associated with poor prognosis. Therefore, identifying cirrhotic patients with AKI who are at high risk of mortality is very important and may be helpful for providing timely medical interventions to improve the prognosis of these patients. However, studies focused on investigating the risk factors for the mortality of cirrhotic patients with AKI were scarce.

AIM

To identify risk factors for mortality and establish a nomogram for predicting the prognosis of these patients.

METHODS

Two hundred fifty consecutive patients with cirrhosis and AKI were recruited and randomly divided into training cohort (n = 173) and validation cohort (n = 77). In the training cohort, potential risk factors for death were identified by performing a Cox regression analysis, and a nomogram was established. The predictive performance of the nomogram was internally and externally validated by calculating the area under the receiver operating characteristic curve (AUROC), constructing a calibration curve and performing decision curve analysis.

RESULTS

The serum sodium level, international normalized ratio, peak serum creatinine level > 1.5 mg/dL, the presence of hepatic encephalopathy and diabetes were potential risk factors for mortality of cirrhotic patients with AKI in the training dataset. A prognostic nomogram incorporating these variables was established for predicting the overall survival of these patients. Compared with Child-Turcotte-Pugh, the model for end-stage liver disease (MELD) and the MELD-Na scores, the nomogram in predicting 90- and 180-d mortality exhibited better discriminatory power with AUROCs of 0.792 and 0.801 for the training dataset and 0.817 and 0.862 for the validation dataset, respectively. With a nomogram score of 98, patients were divided into low- and high-risk groups, and high-risk patients had a higher mortality rate.

CONCLUSION

A prognostic nomogram displayed good performance for predicting the overall survival of cirrhotic patients with AKI, and will assist clinicians in evaluating the prognosis of these patients.

Distinct Subtyping of Successful Weaning from Acute Kidney Injury Requiring Renal Replacement Therapy by Consensus Clustering in Critically Ill Patients

Background: Clinical decisions regarding the appropriate timing of weaning off renal replacement therapy (RRT) in critically ill patients are complex and multifactorial. The aim of the current study was to identify which critical patients with acute kidney injury (AKI) may be more likely to be successfully weaned off RRT using consensus cluster analysis. Methods: In this study, critically ill patients who received RRT at three multicenter referral hospitals at several timepoints from August 2016 to July 2018 were enrolled. An unsupervised consensus clustering algorithm was used to identify distinct phenotypes. The outcomes of interest were the ability to wean off RTT and 90-day mortality. Results: A total of 124 patients with AKI requiring RRT (AKI-RRT) were enrolled. The 90-day mortality rate was 30.7% (38/124), and 49.2% (61/124) of the patients were successfully weaned off RRT for over 90 days. The consensus clustering algorithm identified three clusters from a total of 45 features. The three clusters had distinct features and could be separated according to the combination of urinary neutrophil gelatinase-associated lipocalin to creatinine ratio (uNGAL/Cr), Sequential Organ Failure Assessment (SOFA) score, and estimated glomerular filtration rate at the time of weaning off RRT. uNGAL/Cr (hazard ratio [HR] 2.43, 95% confidence interval [CI]: 1.36–4.33) and clustering phenotype (cluster 1 vs. 3, HR 2.7, 95% CI: 1.11–6.57; cluster 2 vs. 3, HR 44.5, 95% CI: 11.92–166.39) could predict 90-day mortality or re-dialysis. Conclusions: Almost half of the critical patients with AKI-RRT could wean off dialysis for over 90 days. Urinary NGAL/Cr and distinct clustering phenotypes could predict 90-day mortality or re-dialysis.

Predictors of Development of Hepatorenal Syndrome in Hospitalized Cirrhotic Patients with Acute Kidney Injury

Hepatorenal syndrome (HRS) is a type of acute kidney injury (AKI), occurring in patients with decompensated liver cirrhosis and is associated with high mortality. We aim to describe the predictors associated with the development of HRS in cirrhotic patients with AKI. We retrospectively analyzed 529 cirrhotic patient encounters with AKI across all Northwell Health institutions between 1 January 2015 and 31 December 2018. We performed multivariate analyses to determine independent predictors of development of HRS. Alcoholic cirrhosis was the most common identified etiology of cirrhosis. The mean Model for End-Stage Liver Disease Scorewas18 (±7). Ascites was the most commonly identified clinical feature of portal hypertension. Infection was identified in 38.4% of patients with urinary tract infection/pyelonephritis being the most common. Spontaneous bacterial peritonitis occurred in 5.9% of patients. The most common cause of AKI was pre-renal. Hepatorenal syndrome was identified in 9.8% of patient encounters. Predictors of HRS were history of ascites, serum creatinine >2.5 mg/dL, albumin <3 g/dL, bilirubin >2 mg/dL and spontaneous bacterial peritonitis. We demonstrate strong predictors for the development of HRS which can aid clinicians to attain an early diagnosis of HRS, leading to prompt and targeted management and improving outcomes.

Prognostic Implications of a Cumulative Renal Score Based on Both Serum Creatinine and Urine Output Criteria for Staging of Acute Kidney Injury: A Cohort Study

Purpose

Traditionally, the Kidney Disease: Improving Global Outcomes (KDIGO) stages acute kidney injury (AKI) into three stages based on the highest severity of increase in serum creatinine (SC) or urine output (UO) criteria. Clinically, however, the two criteria do not provide equivalent information. Thus, we aimed to develop a cumulative renal score (the sum of the highest KDIGO SC and UO severity stages) for staging of AKI, expanding the original three KDIGO stages to six stages. We hypothesized that the cumulative renal score would more accurately describe AKI severity and outcomes.

Patients and Methods

Critically ill adult patients were identified from the Multi-parameter Intelligent Monitoring in Intensive Care III Database. The primary outcome was hospital mortality. Logistic regression was used to explore the association between cumulative renal score and hospital mortality.

Results

A total of 17,404 critically ill adult patients were enrolled. Patients with higher cumulative renal scores had greater hospital mortality than patients with lower cumulative renal scores (score 0, 7.6%; score 1, 9.3%; score 2, 12.5%; score 3, 18.9%; score 4, 27.1%; score 5, 34.7%; score 6, 46.8%, p < 0.001). After adjustment for significant covariates, relative to cumulative renal score 0, cumulative renal scores 2–6 were associated with increased hospital mortality. Within the traditional KDIGO stage 2 AKI, when compared with cumulative renal score 2, cumulative renal score 4 had increased hospital mortality. Within the traditional KDIGO stage 3 AKI, when compared with cumulative renal score 3, cumulative renal score 6 had increased hospital mortality.

Conclusion

Our study demonstrates that the KDIGO SC and UO criteria have a cumulative effect on AKI severity staging. The cumulative renal score improves the traditional KDIGO AKI staging by applying the two sets of criteria sequentially and provides more insight into the relationship between AKI and outcomes.

Ambiguous definitions for baseline serum creatinine affect acute kidney diagnosis at the emergency department

Background

Acute kidney injury (AKI) incidence is increasing, however AKI is often missed at the emergency department (ED). AKI diagnosis depends on changes in kidney function by comparing a serum creatinine (SCr) measurement to a baseline value. However, it remains unclear to what extent different baseline values may affect AKI diagnosis at ED.

Methods

Routine care data from ED visits between 2012 and 2019 were extracted from the Utrecht Patient Oriented Database. We evaluated baseline definitions with criteria from the RIFLE, AKIN and KDIGO guidelines. We evaluated four baseline SCr definitions (lowest, most recent, mean, median), as well as five different time windows (up to 365 days prior to ED visit) to select a baseline and compared this to the first measured SCr at ED. As an outcome, we assessed AKI prevalence at ED.

Results

We included 47,373 ED visits with both SCr-ED and SCr-BL available. Of these, 46,100 visits had a SCr-BL from the − 365/− 7 days time window. Apart from the lowest value, AKI prevalence remained similar for the other definitions when varying the time window. The lowest value with the − 365/− 7 time window resulted in the highest prevalence (21.4%). Importantly, applying the guidelines with all criteria resulted in major differences in prevalence ranging from 5.9 to 24.0%.

Conclusions

AKI prevalence varies with the use of different baseline definitions in ED patients. Clinicians, as well as researchers and developers of automatic diagnostic tools should take these considerations into account when aiming to diagnose AKI in clinical and research settings.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12882-021-02581-x.

Effects of acute kidney injury on acute pancreatitis patients’ survival rate in intensive care unit: A retrospective study

BACKGROUND

Acute kidney injury (AKI) is one of the most common acute pancreatitis (AP)-associated complications that has a significant effect on AP, but the factors affecting the AP patients’ survival rate remains unclear.

AIM

To assess the influences of AKI on the survival rate in AP patients.

METHODS

A total of 139 AP patients were included in this retrospective study. Patients were divided into AKI group (n = 72) and non-AKI group (n = 67) according to the occurrence of AKI. Data were collected from medical records of hospitalized patients. Then, these data were compared between the two groups and further analysis was performed.

RESULTS

AKI is more likely to occur in male AP patients (P = 0.009). AP patients in AKI group exhibited a significantly higher acute physiologic assessment and chronic health evaluation II score, higher Sequential Organ Failure Assessment score, lower Glasgow Coma Scale score, and higher demand for mechanical ventilation, infusion of vasopressors, and renal replacement therapy than AP patients in non-AKI group (P < 0.01, P < 0.01, P = 0.01, P = 0.001, P < 0.01, P < 0.01, respectively). Significant differences were noted in dose of norepinephrine and adrenaline, duration of mechanical ventilation, maximum and mean values of intra-peritoneal pressure (IPP), maximum and mean values of procalcitonin, maximum and mean serum levels of creatinine, minimum platelet count, and length of hospitalization. Among AP patients with AKI, the survival rate of surgical intensive care unit and in-hospital were only 23% and 21% of the corresponding rates in AP patients without AKI, respectively. The factors that influenced the AP patients’ survival rate included body mass index (BMI), mean values of IPP, minimum platelet count, and hospital day, of which mean values of IPP showed the greatest impact.

CONCLUSION

AP patients with AKI had a lower survival rate and worse relevant clinical outcomes than AP patients without AKI, which necessitates further attention to AP patients with AKI in surgical intensive care unit.

Current knowledge about biomarkers of acute kidney injury in liver cirrhosis

Acute kidney injury (AKI) is common in advanced cirrhosis. Prerenal azotemia, hepatorenal syndrome, and acute tubular necrosis are the main causes of AKI in patients with cirrhosis. Evaluation of renal function and differentiation between functional and structural kidney injury are important issues in the management of cirrhosis. However, AKI in cirrhosis exists as a complex clinical spectrum rather than concrete clinical entity. Based on current evidence, changes in serum creatinine (Cr) levels remain the most appropriate standard for defining AKI in cirrhosis. However, serum Cr has a limited role in assessing renal function in this population. This review examines previous studies that investigated the ability of recent biomarkers for AKI in cirrhosis from the perspective of earlier and accurate diagnosis, classification of AKI phenotype, and prediction of clinical outcomes. Serum cystatin C and urine neutrophil gelatinase-associated lipocalin have been extensively studied in cirrhosis, and have facilitated improved diagnosis and prognosis prediction in patients with AKI. In addition, urine N-acetyl-β-D-glucosaminidase, interleukin 18, and kidney injury molecule 1 are other promising biomarkers for advanced cirrhosis. However, the clinical significance of these markers remains unclear because there are no cut-off values defining the normal range and differentiating phenotypes of AKI. In addition, AKI has been defined in terms of serum Cr, and renal biopsy-the gold standard-has not been carried out in most studies. Further discovery of innovate biomarkers and incorporation of various markers could improve the diagnosis and prognosis prediction of AKI, and will translate into meaningful improvements in patient outcomes.

Different Severity of Clinical Outcomes Between the 2 Subgroups of Stage 1 Acute Kidney Injury After Liver Transplantation

BACKGROUND

Although the Kidney Disease: Improving Global Outcomes (KDIGO) criteria is used to define acute kidney injury (AKI) after liver transplantation, the criteria was criticized for including 2 heterogeneous groups of different serum creatinine (sCr) criteria together in AKI stage 1. We investigated whether there are significant differences in clinical outcomes between 2 subgroups of patients within AKI stage 1.

METHODS

A total of 1440 cases were reviewed. The AKI stage 1 (n = 443) were divided into 2 subgroups based on changes in sCr level (stage 1a: ≥0.3 mg/dL of absolute sCr increase, n = 251; stage 1b: ≥50% relative sCr increase, n = 192). Propensity score analysis was performed between stage 1a and 1b groups, yielding 157 matched pairs. We compared the length of hospital stay, early allograft dysfunction, and 5-year all-cause mortality between these subgroups after matching. Kaplan-Meier analyses were performed to compare the graft or overall survival between the subgroups after matching. Sensitivity analysis for Acute Kidney Injury Network (AKIN) criteria was performed.

RESULTS

Length of hospital stay and 5-year all-cause mortality was significantly worse in patients with stage 1b compared to stage 1a after matching. Five-year graft or patient survival was significantly worse in patients with stage 1b compared to stage 1a after matching (Log-rank test P = 0.022 and P = 0.027, respectively). These results were the same regarding AKIN criteria.

CONCLUSIONS

The KDIGO criteria for AKI stage 1 could be further divided into 2 substages with different severity of clinical outcomes. This modified criteria could give additional prognostic information in patients undergoing liver transplantation.

Incidence, Mortality and Predictors of Acute Kidney Injury in Patients with Cirrhosis: A Systematic Review and Meta-analysis

Background and Aims: Acute kidney injury (AKI) is common in patients with cirrhosis but the incidence is heterogeneous among studies. We performed a meta-analysis to describe the incidence of AKI and its impact on patient mortality in patients with cirrhosis. We also evaluated the admission variables predicting development of AKI. Methods: A systematic search of various databases was performed up to November 2018. Meta-analyses were performed using random effects models. Results: Of 18,474 patients with cirrhosis from 30 selected studies, 5,648 developed AKI, with a pooled incidence of 29% (95% confidence interval [CI]: 28-30%, I 2 of 99%). In-hospital mortality assessed in eight studies was six-fold higher among AKI patients, as compared to those without AKI (odds ratio [OR] 6.72, 95% CI: 3.47-13, p<0.0001, I 2 of 70%). Three studies on patients admitted to intensive care showed about six-fold higher mortality among AKI patients (OR 5.90, 95% CI: 3.21-10.85, p>0.0001). Mortality remained significantly high, at days 30 and 90 and even at 1-year follow up after development of AKI. Of 12 admission variables analyzed, model for end-stage liver disease score, Child-Pugh-Turcotte stage C, presence of ascites, and presence of sepsis/septic shock were statistically significant risk factors for AKI. Conclusions: AKI occurred in about 29% of patients with cirrhosis and is associated with a six-fold increased risk of in-hospital mortality. Mortality remained high even in long-term follow-up of 1 year. Patients at risk for AKI development can be recognized at admission. Prospective studies are needed to develop strategies for improving outcome of these patients.

Rates and risk factors for nephrotoxicity and ototoxicity among tuberculosis patients in Tbilisi, Georgia

SETTING: Treatment of multidrug-resistant tuberculosis (MDR-TB) is lengthy and utilizes second-line anti-TB drugs associated with frequent adverse drug reactions (ADRs).OBJECTIVE: To evaluate the prevalence of and risk factors for ADRs among patients with MDR- and extensively drug-resistant TB (XDR-TB).DESIGN: A retrospective chart review of patients initiating treatment for M/XDR-TB in 2010-2012 in Tbilisi, Georgia.RESULTS: Eighty (54%) and 38 (26%) of 147 patients developed nephrotoxicity per RIFLE (Risk, Injury, Failure, Loss of kidney function, and End-stage kidney disease) classification and ototoxicity, respectively. Twenty-five (17%) patients required permanent interruption of injectables due to an ADR. Median hospital stay, total treatment duration and number of regimen changes were higher among those with nephrotoxicity and/or ototoxicity, compared to those without (P < 0.01). Multinomial logistic regression analysis identified increasing age (per year) as a risk factor for nephrotoxicity (aOR 1.08, 95%CI 1.03-1.12) and for both, nephro- and ototoxicity (aOR 1.11, 95%CI 1.05-1.17). Low baseline creatinine clearance (CrCl) was a significant risk factor for developing nephrotoxicity (aOR 1.05, 95%CI 1.02-1.07).CONCLUSION: Second-line injectable drug-related ADRs are common among M/XDR-TB patients. Patients with increasing age and low baseline CrCl should be monitored closely for injectable-related ADRs. Notably, our findings support WHO's latest recommendations on introduction of injectable free anti-TB treatment regimens.

Role of thrombocytopenia in risk stratification for acute kidney injury after living donor liver transplantation

The aim of our study was to investigate pre and intraoperative clinical factors, including platelet count, which could inform risk stratification of early acute kidney injury (AKI) after living donor liver transplantation (LDLT). Additionally, the impact of severe thrombocytopenia on AKI risk was assessed using a propensity score (PS)-matched analysis. In total, 591 adult patients who underwent LDLT between January 2009 and December 2018 at our hospital were retrospectively analyzed. Early postoperative AKI was determined based on the KDIGO criteria, and 149 patients (25.2%) developed AKI immediately after surgery. In a multivariate analysis, a lower preoperative platelet count was significantly associated with early postoperative AKI, together with diabetes mellitus, lower hourly urine output, and longer graft ischemic time; furthermore, a decrease in platelet count was correlated with AKI severity. After adjusting for the PS, the probability of AKI was significantly (1.9-fold) higher in patients with severe thrombocytopenia than in those without severe thrombocytopenia. Patients with thrombocytopenia showed a higher postoperative incidence of AKI and a higher requirement for dialysis than those without thrombocytopenia. The platelet count can easily be obtained via regular blood analysis of patients scheduled for LDLT and can be used to identify patients at risk for AKI.

Acute kidney injury in critically ill cirrhotic patients with spontaneous bacterial peritonitis: a comparison of KDIGO and ICA criteria

INTRODUCTION

Acute kidney injury (AKI) is an important independent predictor of mortality in cirrhotic patients with spontaneous bacterial peritonitis (SBP). However, the definition of AKI in cirrhosis has been debated for many years. This study aims to compare the prediction accuracy of Kidney Disease: Improving Global Outcomes (KDIGO) and International Club of Ascites (ICA) criteria for hospital mortality in cirrhotic patients with SBP admitted to the intensive care unit (ICU).

MATERIAL AND METHODS

Two hundred and sixteen cirrhotic patients with SBP consecutively admitted to the ICU during 2010-2017 were retrospectively analyzed. Demographic parameters and clinical variables were collected with case report forms. Risk factors for hospital mortality were identified through a multivariate logistic regression analysis. The predictive value of ICA and KDIGO criteria was analyzed by the area under the receiver operating characteristic curve (AUROC). The primary endpoint was hospital mortality.

RESULTS

Overall hospital mortality in our population was 73.6%. Incidence of AKI was 83.8% and 81.5% according to the KDIGO and ICA classifications respectively, associated with increased in-hospital and 180-day mortality. The AKI was an independent risk factor for hospital mortality. The risk factor of AKI according to KDIGO was greater than that of ICA. The AUROC for in-hospital mortality for ICA and KDIGO was 0.730 and 0.752, respectively. However, the predictive ability of ICA criteria for in-hospital mortality was non-inferior to that of KDIGO criteria (p = 0.123).

CONCLUSIONS

Both ICA and KDIGO criteria were good tools with excellent prediction performance for hospital mortality in cirrhotic patients with SBP admitted to the ICU.

Development and validation of quick Acute Kidney Injury-score (q-AKI) to predict acute kidney injury at admission to a multidisciplinary intensive care unit

AKI is associated with increased risk of death, prolonged length of stay and development of de-novo chronic kidney disease. The aim of our study is the development and validation of prediction models to identify the risk of AKI in ICU patients up to 7 days. We retrospectively recruited 692 consecutive patients admitted to the ICU at San Bortolo Hospital (Vicenza, Italy) from 1 June 2016 to 31 March 2017: 455 patients were treated as the derivation group and 237 as the validation group. Candidate variables were selected based on a literature review and expert opinion. Admission eGFR< 90 ml/min /1.73 mq (OR 2.78; 95% CI 1.78–4.35; p<0.001); SOFAcv ≥ 2 (OR 2.23; 95% CI 1.48–3.37; p<0.001); lactate ≥ 2 mmol/L (OR 1.81; 95% CI 1.19–2.74; p = 0.005) and (TIMP-2)•(IGFBP7) ≥ 0.3 (OR 1.65; 95% CI 1.08–2.52; p = 0.019) were significantly associated with AKI. For the q-AKI score, we stratified patients into different AKI Risk score levels: 0–2; 3–4; 5–6; 7–8 and 9–10. In both cohorts, we observed that the proportion of AKI patients was higher in the higher score levels.

Effect of continuous furosemide infusion on outcome of acute kidney injury

Objective:

To evaluate the clinical effects of continuous intravenous infusion with high-dose furosemide on early acute kidney injury (AKI) complicated with acute lung edema.

Methods:

Ninety patients who had been treated by furosemide at routine dose for 12 hour but with unsatisfactory outcomes were selected and subjected to continuous intravenous infusion with high-dose furosemide. The dose was adjusted according to hourly urine output. Serum levels of urea nitrogen, creatinine and potassium, pH, oxygenation index and mechanical ventilation time before and 6, 12, 24, 48 and 72 hour after treatment were compared.

Results:

The urine outputs before and 6, 12, 24, 48 and 72 hour after treatment were (10.71 ± 1.81), (164.52 ± 21.42), (189.71 ± 29.61), (181.33 ± 23.52), (176.82 ± 24.80) and (164.52 ± 18.91) ml/h respectively. Compared with data before treatment, the serum levels of urea nitrogen, creatinine and potassium significantly decreased while pH and oxygenation index significantly increased after six hour of treatment (P<0.05). After treatment, the kidney functions of 80 patients (88.9%) were completely recovered, without obvious adverse reactions.

Conclusion:

For patients with early AKI complicated with acute pulmonary edema who cannot be cured by diuretic agent at routine dose, high-dose furosemide increases urine output and improves success rate.

Clinical Aspects and Prognosis Evaluation of Cirrhotic Patients Hospitalized with Acute Kidney Injury

BACKGROUND

Acute kidney injury occurs in approximately 20% of hospitalized cirrhotic patients. Mortality is estimated at 60% within a month and 65% within a year.

AIMS

To evaluate survival in 30 days and in 3 months of cirrhotic patients hospitalized with acute kidney injury, identifying factors associated with mortality.

METHODS

52 patients with cirrhosis admitted to an academic tertiary center who presented acute kidney injury according to the International Club of Ascites criteria were evaluated. Clinical and laboratory data was collected at diagnosis between 2011 and 2015.

RESULTS

Average age was 54.6 (±10.7) years and 69.2% were male. The average MELD, MELD-Na, and Child-Pugh scores were 21.9 (±7.0), 24.5 (±6.7), and 10.1 (±2.2), respectively. Thirty patients (57.7%) were in acute kidney injury stage 1, 16 (30.8%) in stage 2, and six (11.6%) in stage 3. Mortality was 28.6% in 30 days and 44.9% in three months. In multivariate analysis, variables that were associated independently to mortality were lack of response to expansion treatment and Child-Pugh score. Mortality was 93.3% in three months among nonresponders compared to 28.6% among those who responded to volume expansion (p<0.0001).

CONCLUSION

Acute kidney injury in cirrhosis has dire prognosis, particularly in patients with advanced cirrhosis and in nonresponders to volume expansion.

Evaluation of the criteria of hepatorenal syndrome type of acute kidney injury in patients with cirrhosis admitted to ICU

INTRODUCTION

Acute kidney injury (AKI) is a common and devastating complication in patients with cirrhosis. In 2015, the International Club of Ascites (ICA) proposed the definition of hepatorenal syndrome (HRS) type of AKI (HRS-AKI) in patients with cirrhosis. This study aims to evaluate the criteria of HRS-AKI in patients with cirrhosis admitted to ICU with regard to the prognosis.

METHODS

A total of 349 cirrhotic patients consecutively admitted to intensive care unit (ICU) from 2010 to 2017 were retrospectively analyzed. Demographic parameters and clinical variables were collected with case report forms. The occurrence of AKI was determined according to ICA-AKI criteria. The phenotypes of AKI comprised pre-renal azotemia (PRA), acute tubular necrosis (ATN) and HRS. In our study, patients with PRA or ATN were classified to the non-HRS-AKI group.

RESULTS

The incidence of AKI was 73.0%, comprising PRA (18.6%), ATN (16.3%) and HRS (38.1%). The overall hospital mortality was 64.5%. Patients with AKI had a significantly higher in-hospital (76.1%) and 180-d (86.7%) mortality. AKI type was an independent risk factor for in-hospital mortality by a multivariate logistic regression. The in-hospital and 180-d mortality rates were of no significant difference among patients with HRS-AKI stages 1-3.

CONCLUSIONS

AKI is common in patients with cirrhosis admitted to ICU, associated with significant in-hospital mortality. HRS-AKI was the most common and severe type of AKI in patients with cirrhosis admitted to ICU. The current staging system may not be applicable for HRS-AKI in patients with cirrhosis admitted to ICU.

Hyperchloremia and postoperative acute kidney injury: a retrospective analysis of data from the surgical intensive care unit

Background

Whether perioperative hyperchloremia can induce postoperative acute kidney injury (AKI) is controversial. We investigated the association between perioperative hyperchloremia and postoperative AKI in patients admitted to the intensive care unit (ICU) after surgery.

Methods

We performed a retrospective observational study of patients admitted to the surgical ICU at a single tertiary care hospital between January 2011 and June 2016. Our primary objective was to determine whether hyperchloremia or an increase in serum chloride levels was associated with postoperative AKI. Perioperative hyperchloremia was defined as serum chloride levels ≥ 110 mmol·L^− 1 during postoperative days (PODs) 0–3. The increase in serum chloride levels was defined as the difference between preoperative and maximum postoperative serum chloride levels during the first 3 days after surgery.

Results

Of the 7991 patients included in the final analysis, 1876 (23.5%) developed hyperchloremia during PODs 0–3, and 1187 (14.9%) developed postoperative AKI. Exposure to hyperchloremia during the first 3 days after surgery was not associated with postoperative AKI (odds ratio, 1.09; 95% confidence interval, 0.80–1.49; P = 0.571). However, among patients with preoperative chronic kidney disease stage ≥ 3 (estimated glomerular filtration rate < 60 mL·min^− 1·1.73·m^− 2), the incidence of postoperative AKI was higher in patients with an increase > 6 mmol·L^− 1 in serum chloride levels than in patients with an increase ≤ 1 mmol·L^− 1 (odds ratio, 1.42; 95% confidence interval, 1.09–1.84; P = 0.009). In addition, the incidence of postoperative AKI stage ≥ 2 was not associated with exposure to hyperchloremia or with the increase in serum chloride levels during PODs 0–3, regardless of preoperative kidney function.

Conclusions

Exposure to perioperative hyperchloremia is not associated with postoperative AKI in surgical ICU patients. However, in patients with moderate-to-severe chronic kidney disease (stage ≥ 3), a substantial perioperative increase in serum chloride levels may reflect a higher risk of AKI.

Electronic supplementary material

The online version of this article (10.1186/s13054-018-2216-5) contains supplementary material, which is available to authorized users.

Risk factors, mortality and acute kidney injury outcomes in cirrhotic patients in the emergency department

Background

Acute kidney injury (AKI) is common in cirrhotic patients and is associated with negative outcomes. The aim of this study was to evaluate the presence of AKI and its progression according to KDIGO (Kidney Disease: Improving Global Outcomes) criteria in cirrhotic patients admitted to the emergency department and to determine the association of AKI with hospital mortality.

Methods

This retrospective study included 258 cirrhotic patients admitted to the emergency department of a university hospital from March 2015 to February 2017. AKI was diagnosed and classified according to the KDIGO criteria.

Results

The overall incidence of AKI in cirrhotic patients was 53.9%, and the overall hospital mortality was 28.4%. Mortality was associated with the presence, stage, and progression of AKI. Patients with AKI stage 1 and sCr < 1.5 mg/dl (KDIGO 1a) had a lower mortality rate than patients with AKI stage 1 and sCr > 1.5 mg/dl (KDIGO 1b). In the logistic regression analysis, three variables were independently associated with hospital mortality: cancer, AKI and progression of AKI.

Conclusions

According to the data presented, a single measure of creatinine is not enough, and there is a need for meticulous follow-up of the renal function of patients with hepatic cirrhosis hospitalized in an emergency unit. In addition, this study reinforces the need for subclassification of KDIGO 1 in cirrhotic patients, since patients with acute renal injury and creatinine greater than 1.5 mg/dL present a worse clinical outcome.

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.

Predictive Value of Serum Creatinine, Blood Urea Nitrogen, Uric Acid, and β2-Microglobulin in the Evaluation of Acute Kidney Injury after Orthotopic Liver Transplantation

Background

As a major complication after orthotopic liver transplantation (OLT), the occurrence of acute kidney injury (AKI) is frequently defined by serum creatinine (Cr); however, the accuracy of commonly used blood urea nitrogen (BUN), uric acid (UA), and β₂-microglobulin (β₂-MG) remains to be explored. This retrospective study compared the accuracy of these parameters for post-OLT AKI evaluation.

Methods

Patients who underwent OLT in three centers between July 2003 and December 2013 were enrolled. The postoperative AKI group was diagnosed by the Kidney Disease Improving Global Outcomes (KDIGO) criteria and classified by stage. Measurement data were analyzed using the t-test or Wilcoxon rank-sum test; enumerated data were analyzed using the Chi-square test or Fisher's exact test. Diagnostic reliability and predictive accuracy were evaluated using receiver operating characteristic (ROC) curve analysis.

Results

This study excluded 976 cases and analyzed 697 patients (578 men and 119 women); the post-OLT AKI incidence was 0.409. Compared with the no-AKI group, the AKI group showed very significant differences in Model for End-stage Liver Disease score (14.74 ± 9.91 vs. 11.07 ± 9.54, Z = 5.404; P < 0.001), hepatic encephalopathy (45 [15.8%] vs. 30 [7.3%], χ² = 12.699; P < 0.001), hemofiltration (28 [9.8%] vs. 0 [0.0%], χ² = 42.171; P < 0.001), and 28-day mortality (23 [8.1%] vs. 9 [2.2%], χ² = 13.323; P <0.001). Moreover, mean values of Cr, BUN, UA, and β₂-MG in the AKI group differed significantly at postoperative days 1, 3, and 7 (all P < 0.001). ROC curve area was 0.847 of Cr for the detection of AKI Stage 1 (sensitivity 80.1%, specificity 75.7%, cutoff value 88.23 μmol/L), 0.916 for Stage 2 (sensitivity 87.6%, specificity 82.6%, cutoff value 99.9 μmol/L), and 0.972 for Stage 3 (sensitivity 94.1%, specificity 88.2%, cutoff value 122.90 μmol/L).

Conclusion

The sensitivity and specificity of serum Cr might be a high-value indicator for the diagnosis and grading of post-OLT AKI.

Acute Variceal Bleeding Causes Significant Morbidity

BACKGROUND AND AIMS

The need for primary prophylaxis of variceal bleeding in children is unclear due to insufficient evidence of the efficacy of prophylactic therapy and the mortality and morbidity associated with the first bleeding event. Previous studies have provided estimates of mortality. We aimed to investigate the morbidity associated with acute variceal bleeding (AVB) in children and to identify contributing factors.

METHODS

We retrospectively reviewed children with chronic liver disease or portal vein thrombosis admitted with acute upper gastrointestinal bleeding between 2000 and 2015.

RESULTS

Seventy AVB episodes in 57 children (median age 6 years, 52% girls) were included, 58% with cirrhosis and 30% portal vein thrombosis. Approximately 67% were the patient's first bleed. Post-AVB morbidity was present in 57% of all episodes and in 64% of first bleeds and included: ascites (34%), infection (30%), respiratory complications (24%), intensive care unit admission (20%), rebleed (11%), encephalopathy (7%), acute kidney injury (6%), and failure to control bleed (4%). Two patients died (4% of first bleeds, 8% of cirrhotics' first bleeds) within 6 weeks of bleeding. Median length of stay was 7 days. Overall morbidity was associated with total bilirubin (P = 0.001). Ascites after AVB was associated with pediatric end-stage liver disease (P = 0.0007), total bilirubin (P = 0.001), and cirrhosis (P = 0.006). Median length of stay was longer in patients with morbidities (18 vs 4 days, P < 0.0001).

CONCLUSION

Children with AVB suffer significant morbidity but have a low risk of death. Morbidity should therefore be considered in future studies measuring the risks and benefits of primary prophylaxis of first AVB in children.

[Acute Kidney Injury and Hepatorenal Syndrome]

Acute kidney injury (AKI) is common in patients with liver cirrhosis, occurring in 13-20% of patients hospitalized with decompensated cirrhosis, and is significantly associated with the prognosis. The development and progression of AKI is an independent predictive factor for mortality in these patients. If AKI develops, the renal function declines progressively even if AKI is improved later, the patients have a poorer prognosis compared to those who have not developed AKI. In addition, in patients without appropriate treatment or no improvement with the initial treatment, AKI often progress to hepatorenal syndrome (HRS), which is associated with significant morbidity and mortality. Therefore, early detection and appropriate management for the development of AKI is very important in these patients. Recently, there have been significant revisions in the diagnostic criteria and treatment of AKI and HRS; this manuscript reviews these changes.

AKI in the very elderly patients without preexisting chronic kidney disease: a comparison of 48-hour window and 7-day window for diagnosing AKI using the KDIGO criteria

Objectives

To compare the differences between the Kidney Disease Improving Global Outcomes (KDIGO) criteria of the 48-hour window and the 7-day window in the diagnosis of acute kidney injury (AKI) in very elderly patients, as well as the relationship between the 48-hour and 7-day windows for diagnosis and 90-day mortality.

Patients and methods

We retrospectively enrolled very elderly patients (≥75 years old) from the geriatrics department of the Chinese PLA General Hospital between January 2007 and December 2015. AKI patients were divided into 48-hour and 7-day groups by their diagnosis criteria. AKI patients were divided into survivor and nonsurvivor groups by their outcomes within 90 days after diagnosis of AKI.

Results

In total, 652 patients were included in the final analysis. The median age of the cohort was 87 (84–91) years, the majority (623, 95.6%) of whom were male. Of the 652 AKI patients, 334 cases (51.2%) were diagnosed with AKI by the 48-hour window for diagnosis, while 318 cases (48.8%) were by the 7-day window for diagnosis. The 90-day mortality was 42.5% in patients with 48-hour window AKI and 24.2% in patients with 7-day window AKI. Kaplan–Meier curves showed that 90-day mortality was lower in the 7-day window AKI group than in the 48-hour window AKI group (log rank: P<0.001). Multivariate analysis by the Cox model revealed that 48-hour window for diagnosis hazard ratio (HR=1.818; 95% CI: 1.256–2.631; P=0.002) was associated with higher 90-day mortality.

Conclusion

The 90-day mortality was higher in 48-hour window AKI than in 7-day window AKI in very elderly patients. The 48-hour KDIGO window definition may be less sensitive. The 48-hour KDIGO window definition is significantly better correlated with subsequent mortality and is, therefore, still appropriate for clinical use. Finding early, sensitive biomarkers of kidney damage is a future direction of research.

Administration of Albumin Solution Increases Serum Levels of Albumin in Patients With Chronic Liver Failure in a Single-Arm Feasibility Trial

BACKGROUND & AIMS

Infections are life-threatening to patients with acute decompensation and acute-on-chronic liver failure (AD/ACLF). Patients with AD/ACLF have prostaglandin E2-mediated immune suppression, which can be reversed by administration of albumin; infusion of 20% human albumin solution (HAS) might improve outcomes of infections. We performed a feasibility study to determine optimal trial design, assess safety, and validate laboratory assessments of immune function to inform design of a phase 3 trial.

METHODS

We performed a prospective multicenter, single-arm, open-label trial of 79 patients with AD/ACLF and levels of albumin lower than 30 g/L, seen at 10 hospitals in the United Kingdom from May through December 2015. Patients were given daily infusions of 20% HAS, based on serum levels, for 14 days or until discharge from the hospital. Rates of infection, organ dysfunction, and in-hospital mortality were recorded. The primary end point was daily serum albumin level during the treatment period. Success would be demonstrated if 60% achieved and maintained serum albumin levels at or above 30 g/L on at least one third of days with recorded levels.

RESULTS

The patients' mean model for end-stage disease score was 20.9 ± 6.6. The primary end point (albumin ≥30 g/L on at least one third of days recorded) was achieved by 68 of the 79 patients; 75% of administrations were in accordance with suggested dosing regimen. Mean treatment duration was 10.3 days (104 ± 678 mL administered). There were 8 deaths and 13 serious adverse events, considered by the independent data-monitoring committee to be consistent with those expected. Twelve of 13 patients that developed either respiratory or cardiovascular dysfunction (based on ward-based clinical definitions) as their only organ dysfunction were alive at 30 days compared with 1 of 3 that developed renal dysfunction. Only 1 case of brain dysfunction was recorded.

CONCLUSIONS

In a feasibility trial, we found that administration of HAS increased serum levels of albumin in patients with AD/ACLF. The dosing regimen was acceptable at multiple sites and deemed safe by an independent data-monitoring committee. We also developed a robust system to record infections. The poor prognosis for patients with renal dysfunction was confirmed. However, patients with cardiovascular or respiratory dysfunction had good outcomes, which is counterintuitive. Severe encephalopathy appeared substantially under-reported, indicating that ward-based assessment of these parameters cannot be recorded with sufficient accuracy for use as a primary outcome in phase 3 trials. Trial registration no: EudraCT 2014-002300-24 and ISRCTN14174793.

Prediction of acute kidney injury in cirrhotic patients: a new score combining renal, liver and inflammatory markers

Introduction

Acute kidney injury (AKI) is common in hospitalized patients with cirrhosis and is associated with poor prognosis. A risk prediction score combining values easily measured at admission could be valuable to stratify patients for prevention, monitoring and early intervention, ultimately improving patient care and outcomes. The aim of this study was to develop a risk score for AKI in a cohort of cirrhotic patients.

Patients and methods

We cross-examined the data from a retrospective analysis of 186 patients with cirrhosis admitted to the Gastroenterology and Hepatology Service of Centro Hospitalar Lisboa Norte from January 2003 to December 2005. AKI was defined as an increase in serum creatinine (SCr)≥0.3 mg/dL within 48 hours or a percentage increase in SCr≥50% from baseline. Neutrophil-to-lymphocyte ratio (NLR) was used as a marker for inflammation. A receiver operating characteristic (ROC) curve was produced to assess the discriminative ability of the variables. Cutoff values were defined as those with highest validity. The final AKI risk score model was assessed using the ROC curve.

Results

A total of 52 patients (28%) developed AKI. Higher baseline SCr (p<0.001), more severe liver disease as evaluated by the modified Model of End-stage Liver Disease (MELD)-Na score (p<0.001) and higher NLR (p=0.028) were independently associated with AKI. The area under the ROC (AUROC) curve for the prediction of AKI was 0.791 (95% CI 0.726–0.847) for SCr, 0.771 (95% CI 0.704–0.829) for modified MELD-Na and 0.757 (95% CI 0.689–0.817) for NLR. Cutoff values with the highest validity for predicting AKI were determined and defined as 0.9 for the SCr, 21.7 for the modified MELD-Na and 6 for the NLR. The risk score was created allowing 3 points if the SCr is higher than 0.9, 1 point if the modified MELD-Na is higher than 21.7 and 1 point if the NLR is higher than 6. The AUROC curve of the risk prediction score for AKI was 0.861. A risk score of ≥2 points predicts AKI in cirrhotic patients with a sensitivity of 88.5% and specificity of 72.4%.

Conclusion

A new score combining SCr, MELD-Na and NLR demonstrated a strong discriminative ability to predict AKI in cirrhotic patients.

Remodeling the model for end-stage liver disease for predicting mortality risk in critically ill patients with cirrhosis and acute kidney injury

Serum creatinine measurement demonstrates a poor specificity and sensitivity for the early diagnosis of acute kidney injury (AKI) in patients with cirrhosis. The existing model for end-stage liver disease (MELD) score reveals multiple pitfalls in critically ill patients with cirrhosis and acute kidney injury (CAKI). The aim of this study was to re-evaluate the role of creatinine values in the existing MELD score and to develop a novel score for CAKI, named the "acute kidney injury-model for end-stage liver disease score" (AKI-MELD score). We extracted 651 CAKI from the Multiparameter Intelligent Monitoring in Intensive Care database. A time-dependent Cox regression analysis was performed for developing remodeled MELD scores (Reweight-MELD score, Del-Cr-MELD score, and AKI-MELD score). The area under the receiver operating characteristic curve provided the discriminative power of scoring models related to outcome. The hazard ratio of creatinine was 1.104 (95% confidence interval [CI], 0.945-1.290; P = 0.211). Reweight-MELD score and Del-Cr-MELD score (decreasing the weight of creatinine) were superior to the original MELD score (all P < 0.001). The new AKI-MELD score consists of bilirubin, the international normalized ratio, and the ratio of creatinine in 48 hours to creatinine at admission. It had competitive discriminative ability for predicting mortality (area under the receiver operating characteristic curve, 0.720 [95% CI, 0.653-0.762] at 30 days, 0.688 [95% CI, 0.630-0.742] at 90 days, and 0.671 [95% CI, 0.612-0.725] at 1 year). Further, AKI-MELD score had significantly higher predictive ability in comparison with MELD score, MELD-Na score, and Updated MELD score (all P < 0.001). Conclusion: The predictive value of creatinine for CAKI should be re-evaluated. AKI-MELD score is a potentially reliable tool to determine the prognosis for mortality of CAKI. (Hepatology Communications 2017;1:748-756).

A new scoring model for the prediction of mortality in patients with acute kidney injury

Currently, little information is available to stratify the risks and predict acute kidney injury (AKI)-associated death. In this present cross-sectional study, a novel scoring model was established to predict the probability of death within 90 days in patients with AKI diagnosis. For establishment of predictive scoring model, clinical data of 1169 hospitalized patients with AKI were retrospectively collected, and 731 patients of them as the first group were analyzed by the method of multivariate logistic regression analysis to create a scoring model and further predict patient death. Then 438 patients of them as the second group were used for validating this prediction model according to the established scoring method. Our results showed that Patient’s age, AKI types, respiratory failure, central nervous system failure, hypotension, and acute tubular necrosis-individual severity index (ATN-ISI) score are independent risk factors for predicting the death of AKI patients in the created scoring model. Moreover, our scoring model could accurately predict cumulative AKI and mortality rate in the second group. In conclusion, this study identified the risk factors of 90-day mortality for hospitalized AKI patients and established a scoring model for predicting 90-day prognosis, which could help to interfere in advance for improving the quality of life and reduce mortality rate of AKI patients.

Quick chronic liver failure-sequential organ failure assessment: an easy-to-use scoring model for predicting mortality risk in critically ill cirrhosis patients

BACKGROUND AND AIM

Critically ill cirrhosis patients have an increased risk of morbidity and mortality, even after admission to the ICU. Our objectives were to compare the predictive accuracy of model for end-stage liver disease (MELD), MELD-Na, UK model for end-stage liver disease, and chronic liver failure-sequential organ failure assessment (CLIF-SOFA) by the development and validation of an easy-to-use prognostic model [named quick CLIF-SOFA (qCLIF-SOFA)] for early risk prediction in critically ill patients with cirrhosis.

PATIENTS AND METHODS

Overall, 1460 patients were extracted from the MIMIC-III database and enrolled in this study at 30-day and 90-day follow-up. qCLIF-SOFA was developed in the established cohort (n=730) and a performance analysis was completed in the validation cohort (n=730) using area under the receiver operating characteristic curve. Results were compared with CLIF-SOFA.

RESULTS

The performance of CLIF-SOFA was significantly better than that of MELD, MELD-Na, and UK model for end-stage liver disease for predicting both 30-day and 90-day mortality (all P<0.05). qCLIF-SOFA consisted of five independent factors (bilirubin, creatinine, international normalized ratio, mean arterial pressure, and vasopressin) associated with mortality. In the established cohort, CLIF-SOFA and qCLIF-SOFA predicted mortality with area under the receiver operating characteristic curve values of 0.768 versus 0.743 at 30-day, 0.747 versus 0.744 at 90-day, and 0.699 versus 0.706 at 1 year, respectively (all P>0.05). A similar result was observed in the validation cohort (0.735 vs. 0.734 at 30 days, 0.723 vs. 0.737 at 90 days, and 0.682 vs. 0.700 at 1 year, respectively, all P>0.05).

CONCLUSION

The utility of CLIF-SOFA was further shown to predict mortality for critically ill cirrhosis patients. The novel and simpler qCLIF-SOFA model showed comparable accuracy compared with existing CLIF-SOFA for prognostic prediction.

Renal function and oxygenation are impaired early after liver transplantation despite hyperdynamic systemic circulation

Background

Acute kidney injury (AKI) occurs frequently after liver transplantation and is associated with the development of chronic kidney disease and increased mortality. There is a lack of data on renal blood flow (RBF), oxygen consumption, glomerular filtration rate (GFR) and renal oxygenation, i.e. the renal oxygen supply/demand relationship, early after liver transplantation. Increased insight into the renal pathophysiology after liver transplantation is needed to improve the prevention and treatment of postoperative AKI. We have therefore studied renal hemodynamics, function and oxygenation early after liver transplantation in humans.

Methods

Systemic hemodynamic and renal variables were measured during two 30-min periods in liver transplant recipients (n = 12) and post-cardiac surgery patients (controls, n = 73). RBF and GFR were measured by the renal vein retrograde thermodilution technique and by renal extraction of Cr-EDTA (= filtration fraction), respectively. Renal oxygenation was estimated from the renal oxygen extraction.

Results

In the liver transplant group, GFR decreased by 40% (p < 0.05), compared to the preoperative value. Cardiac index and systemic vascular resistance index were 65% higher (p < 0.001) and 36% lower (p < 0.001), respectively, in the liver transplant recipients compared to the control group. GFR was 27% (p < 0.05) and filtration fraction 40% (p < 0.01) lower in the liver transplant group. Renal vascular resistance was 15% lower (p < 0.05) and RBF was 18% higher (p < 0.05) in liver transplant recipients, but the ratio between RBF and cardiac index was 27% lower (p < 0.001) among the liver-transplanted patients compared to the control group. Renal oxygen consumption and extraction were both higher in the liver transplants, 44% (p < 0.01) and 24% (p < 0.05) respectively.

Conclusions

Despite the hyperdynamic systemic circulation and renal vasodilation, there is a severe decline in renal function directly after liver transplantation. This decline is accompanied by an impaired renal oxygenation, as the pronounced elevation of renal oxygen consumption is not met by a proportional increase in renal oxygen delivery. This information may provide new insights into renal pathophysiology as a basis for future strategies to prevent/treat AKI after liver transplantation.

Trial registration

ClinicalTrials.gov, NCT02455115. Registered on 23 April 2015.

AKI-CLIF-SOFA: a novel prognostic score for critically ill cirrhotic patients with acute kidney injury

Critically ill cirrhotic patients with acute kidney injury (AKI) are associated with high mortality rates. The aims of this study were to develop a specific prognostic score for critically ill cirrhotic patients with AKI, the acute kidney injury - Chronic Liver Failure - Sequential Organ Failure- Assessment score (AKI-CLIF-SOFA) score. This study focused on 527 cirrhotic patients with AKI admitted to intensive care unit and constructed a new scoring system, the AKI-CLIF-SOFA, which can be used to prognostically assess mortality in these patient population. Parameters included in this model were analysed by cox regression. The area under the receiver operating characteristic curve (auROC) of AKI-CLIF-SOFA scoring system was 0.74 in 30 days, 0.74 in 90 days, 0.72 in 270 days and 0.72 in 365 days. Additionally, this study demonstrated that the new model had more discriminatory power than chronic liver failure- sequential organ failure assessment score (CLIF-SOFA), SOFA, model for end stage liver disease (MELD), kidney disease improving global outcomes (KDIGO) and simplified acute physiology score II (SAPS II) (auROC: 0.72, 0.66, 0.64, 0.62, 0.63 and 0.65 respectively, all P < 0.05) for the prediction of the 365-days mortality. Therefore, AKI-CLIF-SOFA demonstrated a valuable discriminative ability compared with KDIGO, CLIF-SOFA, MELD, SAPS II and SOFA in critically ill cirrhotic patients with AKI.

[Acute Kidney Injury in Cirrhotic Patients with Portal Hypertension]

Acute kidney injury (AKI) is one of the most common manifestations encountered in clinical practice. It is associated with high morbidity and mortality in cirrhotic pre- and post-transplantation patients. Hepatorenal syndrome (HRS), a special form of AKI in cirrhotic patients, was recognized as a consequence of renal vasoconstriction from systemic/renal hemodynamic alterations developed in advanced cirrhosis with portal hypertension. Recently, multiple factors-such as infection/inflammation, underlying glomerulonephritis, bile cast, or increased abdominal pressure-have been considered to contribute to renal dysfunction in cirrhotic patients, which were presumed to induce HRS. Moreover, in addition to changing the definition of AKI in the nephrologic guidelines, the new AKI definition for early diagnosis and intervention based on characteristics of liver cirrhosis has been proposed in an international meeting. This article provides a comprehensive and recent review of AKI definition, laying out the topics in accordance with the pathophysiologic mechanisms and therapeutic interventions of AKI in cirrhotic patients with portal hypertension.

Proteinuria can predict prognosis after liver transplantation

Background

Proteinuria is a manifestation of renal dysfunction and it has been demonstrated to be a significant prognostic factor in various clinical situations. The study was designed to analyze prognosis of patients receiving liver transplantation as well as to determine predictive performance of perioperative proteinuria.

Methods

We retrospectively reviewed data of patients who had received a liver transplant in a medical center between 2002 and 2010. Demographic information and clinical characteristic parameters were recorded on the day of intensive care unit admission before operation and on postoperative days 1, 7, and 14.

Results

Among a total of 323 patients, in-hospital mortality and 90-day mortality rates were 13.0 % (42/323) and 14.2 % (46/323), respectively. Patients with proteinuria on admission had higher rates of acute kidney injury (26.8 % vs. 8.8 %, p < 0.001), severe infection episodes (48.8 % vs. 30.7 %, p = 0.023), hospital death (31.1 % vs. 10.1 %, p < 0.001), and 90-day mortality (37.7 % vs. 10.9 %, p < 0.001). Multivariate analysis showed that proteinuria on admission and Sequential Organ Failure Assessment (SOFA) score were independent predictors of in-hospital mortality. The discriminatory ability of proteinuria plus SOFA was even better than that of SOFA alone, especially on postoperative day 1.

Conclusions

The presence of proteinuria before liver transplantation is supposed to be recognized as a negative predictor for in-hospital survival. Moreover, the presence of proteinuria after liver transplantation can assist in the early prediction of poor short-term prognosis for patients receiving liver transplantation.

A nationwide survey of clinical characteristics, management, and outcomes of acute kidney injury (AKI) - patients with and without preexisting chronic kidney disease have different prognoses

Acute kidney injury (AKI) is a common complication in hospitalized patients. The International Society of Nephrology implemented the "0 by 25" initiative aimed at preventing deaths from treatable AKI worldwide by 2025 and conducted a global snapshot survey in 2014. We joined in the project and conducted this study to compare the epidemiology, risk factors, and prognosis between patients with pure AKI and those with acute-on-chronic kidney disease (ACKD). In this study, we prospectively collected demographic parameters and data on clinical characteristics, baseline comorbidities, management, and outcomes of 201 AKI patients in 18 hospitals in Taiwan from September 2014 to November 2014. The in-hospital mortality rate was 16%. AKI was mostly attributed to sepsis (52%). Multivariate logistic regression indicated that oliguria was a positive independent predictor of in-hospital mortality, whereas preexisting CKD and exposure to nephrotoxic agents were negative independent predictors. The prevalence of vasopressor use, intensive care unit care, and mortality were significantly higher in pure AKI patients than in ACKD patients. Moreover, serum creatinine (SCr) levels significantly increased within 7 days after AKI diagnosis in nonsurvivors but not in survivors in the pure AKI group. By contrast, SCr levels were persistently lower in nonsurvivors than in survivors in the ACKD group during the same period. We thus determined that the prognosis of ACKD patients differed from that of pure AKI patients. Considering the CKD history in the future AKI staging system may improve prognosis prediction.