Diagnostic Criteria For Acute Kidney Injury Research Articles

Reframing acute kidney injury as a pathophysiological continuum of disrupted renal excretory function.

Surrogate measures of glomerular filtration rate (GFR) continue to serve as pivotal determinants of the incidence, severity, and management of acute kidney injury (AKI), as well as the primary reference point underpinning knowledge of its pathophysiology. However, several clinically important deficits in aspects of renal excretory function during AKI other than GFR decline, including acid-base regulation, electrolyte and water balance, and urinary concentrating capacity, can evade detection when diagnostic criteria are built around purely GFR-based assessments. The use of putative markers of tubular injury to detect "sub-clinical" AKI has been proposed to expand the definition and diagnostic criteria for AKI, but their diagnostic performance is curtailed by ambiguity with respect to their biological meaning and context specificity. Efforts to devise new holistic assessments of overall renal functional compromise in AKI would foster the capacity to better personalize patient care by replacing biomarker threshold-based diagnostic criteria with a shift to assessment of compromise along a pathophysiological continuum. The term AKI refers to a syndrome of sudden renal deterioration, the severity of which is classified by precise diagnostic criteria that have unquestionable utility in patient management as well as blatant limitations. Particularly, the absence of an explicit pathophysiological definition of AKI curtails further scientific development and clinical handling, entrapping the field within its present narrow GFR-based view. A refreshed approach based on a more holistic consideration of renal functional impairment in AKI as the basis for a new diagnostic concept that reaches beyond the boundaries imposed by the current GFR threshold-based classification of AKI, capturing broader aspects of pathogenesis, could enhance AKI prevention strategies and improve AKI patient outcome and prognosis.

Comparison of diagnostic criteria for sepsis-associated acute kidney injury in the pediatric intensive care unit: a retrospective cohort study.

pRIFLE (Pediatric Risk, Injury, Failure, Loss, End Stage Renal Disease), KDIGO (Kidney Disease Improving Global Outcomes) and pROCK (Pediatric Reference Change Value Optimized for AKI) are diagnostic criteria used for acute kidney injury (AKI) incidence evaluation. The aim of this study was to explore the diagnostic consistency, incidence and mortality rate, clinical signs, and influencing factors of renal injury related to sepsis in children diagnosed by three different AKI diagnostic criteria, and then evaluate which one was more valuable. A retrospective analysis was performed on the clinical data of children with severe sepsis. The patients were diagnosed and staged according to the 2007 pRIFLE standard, the 2012 KDIGO standard, and the 2018 pROCK standard. The clinical characteristics and prognosis of children with different stages of sepsis were compared between the three diagnostic standards. A total of 62 patients with sepsis were included. Blood stream infection is common (11 cases, 17.74%). According to pRIFLE, KDIGO, and pROCK standards, the incidence of sepsis-associated AKI (SA-AKI) was 74.2%, 67.7%, and 56.5%, respectively. The pRIFLE had the highest diagnostic rate of early detection of SA-AKI. There was no statistical difference in SA-AKI incidence or staging consistency between the pRIFLE and KDIGO groups (κ=0.0671; κ>0.60); the consistency of SA-AKI diagnoses across the three standards was good (all P values <0.05), and pROCK demonstrated a higher specificity. A high Pediatric Risk of Mortality (PRISM) score and high procalcitonin level were independent risk factors. Shock and renal replacement therapy were independent risk factors for SA-AKI death. Death from admission to 28 days after admission was used as an endpoint to draw a survival graph, which revealed that the AKI group had a significantly higher risk of death than did the non-AKI group. The consistency of diagnosing SA-AKI across the three classification criteria was similar, and mortality rate increased with increased SA-AKI staging. The pRIFLE criteria were more sensitive in the early detection of SA-AKI, while the pROCK had higher specificity. There was no significant difference between the pRIFLE and KDIGO in terms of incidence, diagnosis, or staging of SA-AKI.

Differential effect on mortality of the timing of initiation of renal replacement therapy according to the criteria used to diagnose acute kidney injury: an IDEAL-ICU substudy

BackgroundThis substudy of the randomized IDEAL-ICU trial assessed whether the timing of renal replacement therapy (RRT) initiation has a differential effect on 90-day mortality, according to the criteria used to diagnose acute kidney injury (AKI), in patients with early-stage septic shock.MethodsThree groups were considered according to the criterion defining AKI: creatinine elevation only (group 1), reduced urinary output only (group 2), creatinine elevation plus reduced urinary output (group 3). Primary outcome was 90-day all-cause death. Secondary endpoints were RRT-free days, RRT dependence and renal function at discharge. We assessed the interaction between RRT strategy (early vs. delayed) and group, and the association between RRT strategy and mortality in each group by logistic regression.ResultsOf 488 patients enrolled, 205 (42%) patients were in group 1, 174 (35%) in group 2, and 100 (20%) in group 3. The effect of RRT initiation strategy on 90-day mortality across groups showed significant heterogeneity (adjusted interaction p = 0.021). Mortality was 58% vs. 42% for early vs. late RRT initiation, respectively, in group 1 (p = 0.028); 57% vs. 67%, respectively, in group 2 (p = 0.18); and 58% vs. 55%, respectively, in group 3 (p = 0.79). There was no significant difference in secondary outcomes.ConclusionThe timing of RRT initiation has a differential impact on outcome according to AKI diagnostic criteria. In patients with elevated creatinine only, early RRT initiation was associated with significantly increased mortality. In patients with reduced urine output only, late RRT initiation was associated with a nonsignificant, 10% absolute increase in mortality.

The clinical application of ultrasound for acute kidney injury during sepsis-from macroscopic to microscopic renal perfusion perspectives

The aim was to quantify macroscopic renal blood flow and renal cortical microcirculation in patients with septic acute kidney injury (AKI) using ultrasound and contrast-enhanced ultrasound. In this case-control study, patients in the intensive care unit diagnosed with septic AKI were divided into stages 1-3 based on the 2012 KDIGO (Kidney Disease: Improving Global Outcomes) AKI diagnostic criteria. The patients were categorized into mild (stage 1) and severe (stages 2 and 3) groups, while septic patients without AKI served as the control group. Ultrasound parameters such as macrovascular renal blood flow and time-averaged velocity, as well as cardiac function parameters such as cardiac output and cardiac index, were measured. The time-intensity curve in the microcirculation was analyzed through contrast-enhanced ultrasound imaging software to calculate imaging parameters such as peak time, rise time, fall half-time and mean transit time of the interlobar arteries in the renal cortex. In terms of macrocirculation, renal blood flow and time-averaged velocity decreased gradually with the progression of septic acute renal injury (p=0.004, p < 0.001). There was no difference in cardiac output and cardiac index values among the three groups (p=0.17 and p=0.12). In terms of microcirculation, ultrasonic Doppler parameters of the renal cortical interlobular artery, such as peak intensity, risk index and ratio of peak systolic velocity to end-diastolic velocity, gradually increased (all p values <0.05). The temporal contrast-enhanced ultrasound parameters-time to peak, rise time, fall half-time and mean transit time-were prolonged in AKI groups when compared with the control group (p < 0.001, p=0.003, p=0.004 and p=0.009, respectively). In patients with septic AKI, the renal blood flow and time average velocity of macrocirculation in the kidneys are reduced, while the time parameters of microcirculation such as time to peak, rise time, fall half-time and mean transit time are prolonged, especially in patients with severe AKI. These changes are not related to changes in cardiac output or cardiac index.

Effects of postoperative urine protein levels on predicting acute kidney injury in critically ill patients undergoing non-cardiac surgery

Objective: To investigate the predictive value of postoperative urine protein level in critically ill patients undergoing non-cardiac surgery with acute kidney injury (AKI). Methods: A total of 661 critically ill patients undergoing non-cardiac surgery, who visited the Department of Critical Care Medicine of Peking University First Hospital from May 20, 2019 to November 24, 2020, were enrolled in this prospective study. The clinical data of the patient's age, gender, body mass index, laboratory examination, surgical status, etc. were collected. AKI diagnostic criteria of the 2012 KDIGO guidelines were used to diagnose the occurrence of AKI after surgery. The independent predictors of AKI were determined by multivariate logistic regression. Results: The age of this patient cohort was (69±15) years. The prevalence of AKI was 45.4% (300/661). Multivariate logistic regression showed that urine protein semi-quantitative ≥2+(OR=2.62, 95%CI: 1.05-6.56, P=0.039) was independent factor for postoperative AKI in critically ill patients undergoing non-cardiac surgery, other independent factors include higher age (OR=1.04, 95%CI: 1.02-1.06, P=0.001), higher body mass index (BMI) (OR=1.12, 95%CI: 1.04-1.21, P=0.004), lower plasma hemoglobin level (OR=0.98, 95%CI: 0.97-1.00, P=0.019), lower central venous pressure (OR=0.89, 95%CI: 0.83-0.97, P=0.005) and lower total hypotension time (OR=1.01, 95%CI: 1.00-1.01, P=0.041). Conclusions: Urine protein semi-quantitative ≥2+after surgery is an independent predictive factor for the occurrence of postoperative AKI in critically ill patients undergoing non-cardiac surgery. It is important to check urine routine immediately after surgery to detect and deal with high-risk patients.

Accuracy of Liver-Type Fatty Acid-Binding Protein in Predicting Acute Kidney Injury: AMeta-Analysis.

Liver-type fatty acid-binding protein (L-FABP) is a promising biomarker for the early prediction of acute kidney injury (AKI). However, the clinical utility of L-FABP in different populations or settings remains unclear. We present a meta-analysis of studies evaluating the performance of L-FABP in AKI prediction. We performed a literature search in MEDLINE, EMBASE, and Cochrane library, using search terms "acute kidney injury" and "L-FABP." Studies investigating the performance characteristics of L-FABP for the early diagnosis of AKI were included. Data about patient characteristics, diagnostic criteria of AKI, quantitative data required for construction of a 2 × 2 table (number of participants, sensitivity, specificity, and case number), study settings, and outcomes were extracted. The bivariable model was applied to calculate the estimated sensitivity and specificity of L-FABP. A summary ROC curve was created by plotting the true-positive rate against the false-positive rate at various cutoff values from different studies. We found 27 studies reporting measurement of urine (n = 25 studies) or plasma (n = 2 studies) L-FABP. Overall, the estimated sensitivity was 0.74 (95% CI: 0.69-0.80) and specificity was 0.78 (95% CI: 0.71-0.83). L-FABP demonstrated a stable area under the ROC of 0.82 (95% CI: 0.79-0.85) in variable clinical settings including intensive care unit, surgery, and contrast-induced AKI. In subgroup analysis excluding pediatric and post radiocontrast exposure cohorts, L-FABP had comparative diagnostic performance with neutrophil gelatinase associated lipocalin (NGAL). Despite broad prevalence, L-FABP is a clinically useful marker with moderate accuracy in variable clinical settings as demonstrated in our subgroup analysis. Except for pediatric patients and those post-radiocontrast exposure, L-FABP has comparable discriminative capability as NGAL.

Correlation and Diagnostic Value of Serum Cys-C, RBP4, and NGAL with the Condition of Patients with Traumatic Acute Kidney Injury.

There is a lack of targeted biomarkers that can diagnose Acute Kidney Injury (AKI) early and accurately, which leads to deterioration of renal function and even death in patients who do not receive timely and effective treatment. In recent years, an increasing number of studies have shown that AKI-related markers such as cystatin C (Cys-C) and retinol-binding protein (RBP) can be used for early diagnosis of AKI to a certain extent. A total of 262 subjects were included in this study, of which 132 patients with traumatic AKI were enrolled in one group and named as the AKI group; 130 healthy subjects were enrolled in another group and named as the healthy group. AKI patients with different conditions were classified into AKI phase I, II, and III according to the KDIGO AKI diagnostic criteria, with 45, 59, and 28 in each group. In this study, we examined and compared serum Cys-C, RBP4, and neutrophil gelatinase-associated lipid transport protein (NGAL) levels between the AKI and healthy groups and between patients with AKI of different conditions, and the correlation and diagnostic value of three serum markers with the condition of traumatic AKI patients were also analyzed. The results showed that serum Cys-C, RBP4, and NGAL were significantly higher in the AKI group compared with the healthy group (P < 0.05), and the mean concentrations of the three serum markers increased as the severity of the disease increased, while correlation analysis showed that all three serum markers were positively correlated with serum Scr levels (P < 0.001). Further ROC curve analysis was performed, and the diagnostic values of serum Cys C, RBP4, and NGAL alone and in combination for traumatic AKI were 0.769, 0.741, 0.771, and 0.905, respectively. In short, serum Cys C, RBP4, NGAL have important value for the assessment and diagnosis of traumatic AKI patients.

Acute kidney injury and hepatorenal syndrome in cirrhosis.

Acute kidney injury (AKI) in cirrhosis, including hepatorenal syndrome (HRS), is a common and serious complication in cirrhotic patients, leading to significant morbidity and mortality. AKI is separated into two categories, non-HRS AKI and HRS-AKI. The most recent definition and diagnostic criteria of AKI in cirrhosis and HRS have helped diagnose and prognosticate the disease. The pathophysiology behind non-HRS-AKI and HRS is more complicated than once theorized and involves more processes than just splanchnic vasodilation. The common biomarkers clinicians use to assess kidney injury have significant limitations in cirrhosis patients; novel biomarkers being studied have shown promise but require further studies in clinical settings and animal models. The overall management of non-HRS AKI and HRS-AKI requires a systematic approach. Although pharmacological treatments have shown mortality benefit, the ideal HRS treatment option is liver transplantation with or without simultaneous kidney transplantation. Further research is required to optimize pharmacologic and nonpharmacologic approaches to treatment. This article reviews the current guidelines and recommendations of AKI in cirrhosis.

The influence of hyperbilirubinemia on indexes of kidney function in neonates.

To study the influence of hyperbilirubinemia on indexes of neonatal kidney function. A prospective cohort study was conducted September 2019 to March 2020 in Neonatology Department of Xuzhou Central Hospital. Neonates with gestational age ≥ 35 weeks and aged ≤ 7 days were included and divided into mild, moderate, and severe groups according to total serum bilirubin level. Epidemiologic and demographic data and daily urine output were recorded. Total serum bilirubin, serum creatinine, serum cystatin C, serum neutrophil gelatinase-associated lipocalin (NGAL), urine NGAL, and kidney injury molecule-1 were tested before and 12~18 h after phototherapy. Parameters of kidney function were compared between groups. Fifty-three, 52, and 49 neonates were included in the mild, moderate, and severe groups, respectively. Urine NGAL was higher in severe (1.36 ± 0.24 μg/L) compared to moderate (1.22 ± 0.19 μg/L) and mild groups (1.16 ± 0.19 μg/L), and differences were statistically significant (P = 0.004 and < 0.001, respectively). Urine NGAL was not significantly different between moderate and mild groups (P > 0.05). No significant differences in other kidney function indexes were observed between the three groups (all P > 0.05). Significant reduction in urine NGAL levels 12~18 h after stopping phototherapy was found in severe group ((1.17 ± 0.28) μg/L vs. (1.35 ± 0.23) μg/L, P < 0.001). Urine NGAL positively correlated with total serum bilirubin (r = 0.575, P < 0.001). Among all cases, neither serum creatinine nor daily urine output met neonatal acute kidney injury diagnostic criteria. Severe hyperbilirubinemia may temporarily impair renal tubular reabsorption functions in full-term and near-term neonates, which is likely reversible. However, it has little effect on glomerular filtration function. A higher resolution version of the Graphical abstract is available as Supplementary information.

Impact of Enhanced Recovery After Surgery (ERAS) protocol versus standard of care on postoperative Acute Kidney Injury (AKI): A meta-analysis.

Acute kidney injury (AKI) is a common postoperative complication with an incidence of nearly 15%. Relatively balanced fluid management, flexible use of vasoactive drugs, multimodal analgesia containing non-steroidal anti-inflammatory drugs are fundamental to ERAS protocols. However, these basic tenants may lead to an increased incidence of postoperative AKI. A search was done in the PubMed, Embase, Cochrane Library and reference lists to identify relevant studies from inception until May 2020 to be included in this study. Effects were summarized using pooled risk ratios (RRs), mean differences (MDs) and corresponding 95% confidence intervals (Cls) with random effect model. Heterogeneity assessment, sensitivity analysis, and publication bias were performed. A systematic review of nineteen cohort studies covering 17,205 patients, comparing impact of ERAS with conventional care on postoperative AKI was performed. Notably, the ERAS regimen did not increase the incidence of postoperative AKI compared with standard care (RR: 1.21; 95% CI: 0.96 to 1.52; I2 = 53%). Both goal-directed fluid therapy (RR: 1.26; 95% CI: 0.99-1.61; I2 = 55%) and restrictive fluid management (RR: 1.06; 95% CI: 0.57-1.98; I2 = 60%) had no significant effect on the incidence of postoperative AKI. There was no significant statistical difference between different AKI diagnostic criteria (P = 0.43; I2 = 0%). ERAS group had significantly shorter hospital stay (MD: -1.54; 95% CI: -1.91 to -1.17; I2 = 66%). There was no statistical difference in 30-day readmission rate (RR: 0.98; 95% CI: 0.80 to 1.20; I2 = 42%), 30-day reoperation rate (RR: 0.98; 95% CI: 0.71 to 1.34; I2 = 42%) and mortality (RR: 0.81; 95% CI: 0.59 to 1.11; I2 = 0%) between the two groups. This meta-analysis suggests that ERAS protocols do not increase readmission or reoperation rates and mortality while significantly reducing LOS. Most importantly, the ERAS protocol was shown to have no promoting effect on the incidence of postoperative AKI. Even GDFT and restrictive fluid management cannot avoid the occurrence of postoperative AKI, and the ERAS protocol is still worth recommending and its safety is further confirmed.

Biomarker-Guided Risk Assessment for Acute Kidney Injury: Time for Clinical Implementation?

Acute kidney injury (AKI) is a common and serious complication in hospitalized patients, which continues to pose a clinical challenge for treating physicians. The most recent Kidney Disease Improving Global Outcomes practice guidelines for AKI have restated the importance of earliest possible detection of AKI and adjusting treatment accordingly. Since the emergence of initial studies examining the use of neutrophil gelatinase-associated lipocalin (NGAL) and cycle arrest biomarkers, tissue inhibitor metalloproteinase-2 (TIMP-2) and insulin-like growth factor-binding protein (IGFBP7), for early diagnosis of AKI, a vast number of studies have investigated the accuracy and additional clinical benefits of these biomarkers. As proposed by the Acute Dialysis Quality Initiative, new AKI diagnostic criteria should equally utilize glomerular function and tubular injury markers for AKI diagnosis. In addition to refining our capabilities in kidney risk prediction with kidney injury biomarkers, structural disorder phenotypes referred to as “preclinical-” and “subclinical AKI” have been described and are increasingly recognized. Additionally, positive biomarker test findings were found to provide prognostic information regardless of an acute decline in renal function (positive serum creatinine criteria). We summarize and discuss the recent findings focusing on two of the most promising and clinically available kidney injury biomarkers, NGAL and cell cycle arrest markers, in the context of AKI phenotypes. Finally, we draw conclusions regarding the clinical implications for kidney risk prediction.

Modification of Pediatric Sequential Organ Failure Assessment Score Using Acute Kidney Injury Diagnostic Criteria.

To develop a modified pediatric Sequential Organ Failure Assessment score using the acute kidney injury diagnostic criteria and evaluate its performance in predicting mortality. A single-center retrospective study. Fourteen-bed PICU in a tertiary care academic children's hospital. Critically ill children admitted to the PICU between January 2017 and September 2019 with at least more than two serum creatinine measurements-one for baseline and the other within the first 48 hours of PICU admission. None. A total of 755 patients were included. Overall, 265 patients were diagnosed with acute kidney injury using the current acute kidney injury diagnostic criteria. The overall PICU mortality was 5.8%. Patients with acute kidney injury required more vasoactive-inotropic drugs and showed higher illness severity scores, including the Pediatric Risk of Mortality III, Pediatric Logistic Organ Dysfunction 2, pediatric Sequential Organ Failure Assessment, and modified pediatric Sequential Organ Failure Assessment scores, as well as higher PICU mortality than patients without acute kidney injury (p < 0.001). As acute kidney injury stages increase, PICU mortality also increased (p < 0.001). Based on multivariable logistic regression analysis adjusted for age and sex, the modified pediatric Sequential Organ Failure Assessment score was an independent prognostic factor of PICU mortality. The modified pediatric Sequential Organ Failure Assessment score showed better performance in predicting PICU mortality (area under the receiver operating characteristic curve, 0.821; 95% CI, 0.759-0.882) than other severity scores (area under the receiver operating characteristic curve [95% CI] of Pediatric Risk of Mortality III, Pediatric Logistic Organ Dysfunction 2, and pediatric Sequential Organ Failure Assessment scores: 0.788 [0.723-0.853], 0.735 [0.663-0.807], and 0.785 [0.718-0.853], respectively). Acute kidney injury is prevalent and associated with poor clinical outcomes in critically ill children. The modified pediatric Sequential Organ Failure Assessment score, based on the acute kidney injury diagnostic criteria, showed improved performance in predicting PICU mortality. The modified pediatric Sequential Organ Failure Assessment score could be a promising prognostic factor for critically ill children.

Plasma cystatin C versus renal resistive index as early predictors of acute kidney injury in critically ill neonates

Acute kidney injury (AKI) independently predicts morbidity and mortality of critically ill neonates. Serum cystatin C is a promising early biomarker for AKI. Evaluating the renal resistive index (RRI) by Doppler ultrasound demonstrates abnormal intrarenal vascular impendence. The objective of this study was to compare the ability of plasma cystatin C and the RRIto predict AKI early in critically ill neonates. Sixty critically ill neonates in neonatal intensive care units were assigned to three groups: group 1 (cases) of thirty participants fulfilling the AKI diagnostic criteria of neonatal Kidney Disease Improving Global Outcome, group 2 of thirty participants not fulfilling the criteria, as well as the 3rd group of thirty age- and sex-matching healthy participants. Group 1 demonstrated a significantly high mean cystatin C level during the 1st day of incubation compared with the other two groups [group 1 (3.18±1.25), group 2 (1.68±0.66), and group 3 (0.80±0.26)]. Serum creatinine and RRI were insignificantly different among all groups. At a cutoff value of 2.68 (mg/l), cystatin C level had significantly higher area under the curve (AUC) (0.804) than both serum creatinine (0.453) and RRI (0.551) and had 53.3% sensitivity and 100% specificity in the early prediction of neonates with AKI. The RRI had a lower non-significant AUC(0.551) at a cutoff value of 0.53 and had 100% sensitivity and 40% specificity, while serum creatinine had a low non-significant AUC(0.453) at a cutoff value of 0.49 (mg/dl) and had 33.3%sensitivity and 86.7%specificity. Applying regression analysis to predict AKI in critically ill neonates as early as possible, higher plasma cystatin C and lower estimated glomerular filtration rate cystatin were the only independent risk factors within critically ill neonates. The level of plasma cystatin C increased 48h before both RRI and serum creatinine did in critically ill neonates who developed AKI, soit is more reliable in predicting AKI in critically ill neonates than serum creatinine and RRI.

Serum heart-type fatty acid-binding protein as a predictor for the development of sepsis-associated acute kidney injury

ABSTRACTBackground: We analyzed the correlation between heart-type fatty acid-binding protein (HFABP) and the development of acute kidney injury (AKI) in patients with sepsis and estimated the predictive capacity of HFABP for sepsis-associated acute kidney injury (SAKI).Methods: In this retrospective observational study, we screened 2,452 patients who received the HFABP test in the emergency department. 442 admitted patients with sepsis were finally enrolled. Based on the diagnostic criteria for AKI in Kidney Disease: Improving Global Outcomes (KDIGO) guidelines, patients were divided into the no-AKI group (n = 317) and AKI group (n = 125). We analyzed the correlation between HFABP and SAKI occurrence by logistic regression analysis and evaluated the predictive ability of HFABP to SAKI using c-index, net reclassification improvement index (NRI) and integrated discrimination improvement index (IDI).Results: Patients in the AKI group with significantly higher the level of HFABP and in-hospital mortality. HFABP concentration is an independent risk factor for SAKI (OR: 11.398; 95% CI: 6.218–20.891, P < 0.001), but not for in-hospital mortality (OR: 1.189, 95%CI: 0.954–2.607, P = 0.076). The addition of HFABP to the prediction model significantly improved the ROC area (0.867 vs 0.755, P < 0.001), NRI 25.03% (95% CI 9.72–38.51%) and IDI 14.33 (95% CI 11.04–17.62).Conclusion: Serum HFABP is correlated with SAKI development and could become a potential predictive biomarker.

Analysis of risk factors of acute kidney injury in organ donors

Background: To investigate the occurrence and risk factors of acute kidney injury (AKI) in organ donors. Methods: Clinical data of 153 donor patients who donated organs in our hospital from January 2016 to July 2018 were collected. Patients were divided into AKI group and non-AKI group according to AKI diagnostic criteria. Clinical indicators of patients in the two groups were compared, and the related risk factors were analyzed by unifactorial and multivariate logistic regression. Results: The incidence of donor patients complicated with AKI was 48.37%. Unifactorial analysis suggested that the SOFA score, positive rate of blood culture, hypothermia incidence and vasoactive drug dose in donor AKI group were larger than those in non-AKI group. Multivariate Logistic regression analysis showed that the dose of booster drugs (P=0.02, OR=3.53) and the positive rate of blood culture (P=0.01, OR=6.64) were independent risk factors for donor patients complicated with AKI. Conclusion: The incidence of acute kidney injury in organ donors is high, with the dose of booster drugs and the positive rate of blood culture as independent risk factors for evaluation basis to assess the incidence rate of donor patients complicated with AKI.

The incidence of acute kidney injury following cardiac arrest and cardiopulmonary resuscitation in a rat model

Objective: In the current study, we investigated the incidence of acute kidney injury (AKI) induced by cardiac arrest (CA) and cardiopulmonary resuscitation (CPR) and whether such an AKI can recover spontaneously in rats.Methods: We used transesophageal alternating current stimulation to establish 7 min of CA rat model followed by conventional CPR. The experimental rats were randomly divided into three groups (n = 20 per group) according to the different time points after restoration spontaneous circulation (ROSC): the ROSC 24 h, ROSC 48 h, and ROSC 72 h group. The diagnosis of rat AKI refers to the 2012 KDIGO adult AKI diagnostic criteria. The severity of AKI quantified by the serum creatinine (SCR), blood urea nitrogen (BUN) levels and histological features of renal tissue.Results: The incidence rates of AKI in ROSC 24 h, ROSC 48 h, and ROSC 72 h group were 65%, 45%, and 42.9%. Moreover, the values of SCR and BUN were highest at ROSC 24 h, and then gradually decreased with the time of ROSC. The histological changes of the renal tissues such as glomerular collapse, renal tubular cell swelling, and inflammatory cell infiltration had also observed.Conclusion: The incidence of AKI in rats was high after suffering from CA and CPR, but renal function improved with the prolongation of ROSC time, indicating the ability of the kidney to self-repair.

Acute Kidney Injury After Liver Transplantation.

Since the implementation of the Model of End-stage Liver Disease score-based allocation system, the number of transplant candidates with impaired renal function has increased. The aims of this review are to present new insights in the definitions and predisposing factors that result in acute kidney injury (AKI), and to propose guidelines for the prevention and treatment of postliver transplantation (LT) AKI. This review is based on both systematic review of relevant literature and expert opinion. Pretransplant AKI is associated with posttransplant morbidity, including prolonged post-LT AKI which then predisposes to posttransplant chronic kidney disease. Prevention of posttransplant AKI is essential in the improvement of long-term outcomes. Accurate assessment of baseline kidney function at evaluation is necessary, taking into account that serum creatinine overestimates glomerular filtration rate. New diagnostic criteria for AKI have been integrated with traditional approaches in patients with cirrhosis to potentially identify AKI earlier and improve outcomes. Delayed introduction or complete elimination of calcineurin inhibitors during the first weeks post-LT in patients with early posttransplant AKI may improve glomerular filtration rate in high risk patients but with higher rates of rejection and more adverse events. Biomarkers may in the future provide diagnostic information such as etiology of AKI, and prognostic information on renal recovery post-LT, and potentially impact the decision for simultaneous liver-kidney transplantation. Overall, more attention should be paid to pretransplant and early posttransplant AKI to reduce the burden of late chronic kidney disease.

Advances in diagnostic criteria and biomarkers for neonatal acute kidney injury

Acute kidney injury (AKI) has a high incidence in neonates. A variety of perinatal factors may contribute to neonatal AKI, resulting in short- and long-term adverse outcomes, including chronic kidney disease. Early diagnosis and timely treatment can significantly improve the outcomes of these babies. Diagnostic criteria for AKI in adults and children are inapplicable to neonates due to the specific pathophysiological characteristics in newborns. In addition, current diagnosis criteria for neonatal AKI are still inconsistent. These all make it more difficult to diagnose neonatal AKI accurately. New biomarkers for kidney injury, such as neutrophil gelatinase-associated lipocalin, kidney injury molecule-1 and interleukin-18, have been found valuable for early and accurate diagnosis and prognosis of neonatal AKI. However, more studies are required to clarify the influencing factors, diagnostic values and clinical significance of those biomarkers. Key words: Acute kidney injury; Biomarkers; Incidence; Infant, newborn

Risk factor analysis of acute kidney injury after orthotopic liver transplantation

Objective To investigate the risk factors and prognosis of acute kidney injury (AKI) after orthotopic liver transplantation (OLT). Methods The retrospective case-control study was conducted. The clinical data of 127 patients who underwent OLT in the First Affiliated Hospital of Xi′an Jiaotong University from January 2013 to December 2015 were collected. Of 127 patients, 24 were complicated with postoperative AKI, including 17 in grade 1, 5 in grade 2 and 2 in grade 3, and 103 were not complicated with AKI. AKI after OLT was treated according to the diagnostic criteria of AKI from 2012 guidelines of Kidney Disease: Improving Global Outcomes (KDIGO). Observation indicators: (1) risk factors analysis affecting AKI after OLT; (2) comparison of postoperative recovery in patients with different AKI grade; (3) follow-up and survival situations. Follow-up using outpatient examination and telephone interview was performed up to July 2017. Measurement data with normal distribution were represented as ±s, and measurement data with skewed distribution were described as M (range). Univariate analysis was done using the t test and rank sum test. Comparisons of count data and univariate analysis were done using chi-square test or Fisher exact probability. Multivariate analysis was done using the logistic regression model. The survival rate and curve were respectively calculated and drawn by the Kaplan-Meier method, and Log-rank test was used for survival analysis. Results (1) Risk factors analysis affecting AKI after OLT: results of univariate analysis showed that age, combined hypertension, preoperative Child-Pugh score, preoperative model for end-stage liver disease score (MELD), preoperative hemoglobin, preoperative serum albumin, preoperative blood urea nitrogen, preoperative glomerular filtration rate, preoperative prothrombin time, operation time, inferior vena cava occlusion time, duration of anhepatic phase, volume of intraoperative blood loss, total volume of intraoperative blood transfusion, volumes of intraoperative plasma and red blood cells transfusion, duration of postoperative ICU stay, use time of postoperative vasoactive drugs, time of postoperative mechanical ventilation, cases with postoperative infection, body mass index of donor and donor liver cold-ischemia time were related factors affecting occurrence of AKI after OLT (t=4.154, χ2= 8.482, t=5.129, 3.694, 1.294, 9.223, 5.418, Z=4.287, t=2.105, 5.168, 8.182, 10.042, Z=1.074, 0.664, 6.274, 3.712, 1.289, t=1.056, χ2=10.617, t=2.447, 3.371, 1.476, P 0.05). Conclusion Age, preoperative MELD score, preoperative serum albumin, volume of intraoperative blood loss and donor liver cold-ischemia time are independent factors affecting occurrence of AKI after OLT, and there is better recovery in patients with grade 1 of AKI. Key words: Hepatic neoplasms; Liver cirrhosis; Liver transplantation, orthotopic; Acute kidney injury; Risk factors; Prognosis

Continuous contrast-enhanced ultrasound applied to acute kidney injury caused by sepsis: a diagnostic clinical study

To evaluate the diagnostic value of contrast-enhanced ultrasound in acute kidney injury (AKI) caused by sepsis. The sepsis patients admitted to intensive care unit of Tianjin Third Central Hospital from January 2015 to June 2017 were enrolled. All of the patients were completed the 6-hour Bundle treatment and the bilateral renal contrast-enhanced ultrasound within 24 hours, and the peak signal intensity (PSI), peak intensity time (PIT), wash internal rate (WIR) and renal function parameters were measured at the same time. The patients were divided into AKI 24 hours group and non-AKI 24 hours group according to Kidney Disease: Improving Global Outcomes (KDIGO)-AKI diagnostic criteria, and the parameters differences were compared between the two groups. The receiver operating characteristic (ROC) curve were used to analyze the diagnostic value of the parameters. Renal function of the non-AKI group patients was measured again 7 days after hospital admission, and patients were divided into AKI 7 days group and non-AKI 7 days group, and the related parameters of the two groups measured within 24 hours were compared. (1) Ninety-six patients were enrolled, with 39 cases of AKI occurred within 24 hours after admission, and with an incidence of 40.6%. Contrast-enhanced ultrasound showed that the time-intensity curve (TIC) of non-AKI patients manifested as a slow down after rapid rise to the peak, but the AKI patients showed as slow rise to the peak and more slow decrease. Compared with non-AKI 24 hours group, AKI 24 hours group performance as PSI weakened, PIT extended and WIR decreased [PSI (dB): 114.41±19.38 vs. 141.24±24.65, PIT (s): 22.86±4.29 vs. 17.39±3.68, WIR (dB/s): 5.53±4.17 vs. 7.85±1.84, all P < 0.01]. ROC curve analysis showed that area under the ROC curve (AUC) of WIR, PIT, PSI was 0.85, 0.84, 0.82 respectively (all P < 0.01), the cut-off value of WIR was 7.18 dB/S, the sensitivity, specificity and accuracy were 82.05%, 80.70% and 81.25% respectively; the cut-off value of PIT was 18.45 s, the sensitivity, specificity and accuracy were 74.35%, 73.68% and 73.95% respectively; the cut-off values of PSI was 121.21 dB, the sensitivity, specificity and accuracy were 71.79%, 87.72% and 81.25% respectively. (2) The incidence of AKI within 7 days in non-AKI patients was 26.3% (15/57). There were significant differences in PIT, WIR and PSI between AKI 7 days group and non-AKI 7 days group [PSI (dB): 124.97±26.64 vs. 147.02±21.51, PIT (s): 20.61±3.27 vs. 16.24±3.13, WIR (dB/s): 6.81±1.76 vs. 8.22±1.75, all P < 0.05]. However, there was no significant difference in serum creatinine (SCr), blood urea nitrogen (BUN) and creatinine clearance rate (CCr). Compared to SCr and BUN, contrast-enhanced ultrasound parameters can early response to renal dysfunction, and contribute to early diagnosis of sepsis induced AKI.