Combination of Renal Biomarkers Predicts Acute Kidney Injury in Critically Ill Adults

Objective: Most studies so far have focused on the performance of individual biomarkers to detect early acute kidney injury (AKI) in the adult intensive care unit (ICU) patients; however, they have not determined the predictive ability of their combinations. The aim of this study was to compare the predictive abilities of plasma neutrophil gelatinase-associated lipocalin (pNGAL), urine neutrophil gelatinase-associated lipocalin (uNGAL), plasma cystatin C (pCysC), serum creatinine (sCr), and their combinations in detecting AKI in an adult general ICU population. Methods: A total of 100 consecutive ICU patients were included in the analysis. AKI was defined according to RIFLE criteria. Biomarker predictive abilities were evaluated by area under the curve (AUC), net reclassi?cation improvement (NRI), and integrated discrimination improvement (IDI). Results: AKI occurred in 36% of patients 7 days post-admission. All three novel biomarkers as well as sCr had moderate predictive abilities for AKI occurrence. The most efficient combinations (pNGAL + sCr and pNGAL + uNGAL + sCr) were selected to participate in the subsequent analyses. Both combinations, when added to a reference clinical model, increased its AUC significantly (0.858, p = 0.04). Their NRI (0.78, p = 0.0002) was equal to that of pNGAL, but higher than that of the other three biomarkers, whereas their IDI was higher than that of any individual biomarker (0.23, p = 0.0001). Both combinations had better specificities, positive likelihood ratios, and positive predictive values than those of any individual biomarker. Conclusion: The biomarker combinations had better predictive characteristics compared with those of each biomarker alone.     

Chronic Kidney Disease After Liver Transplantation for Acute Liver Failure Is Not Associated With Perioperative Renal Dysfunction

Renal dysfunction of acute liver failure (ALF) may have distinct pathophysiological mechanisms to hepatorenal syndrome of cirrhosis. Yet, the impact of perioperative renal function on posttransplant renal outcomes in ALF patients specifically has not been established. The aims of this study were ( 1 ) to describe the incidence and risk factors for chronic renal dysfunction following liver transplantation for ALF and ( 2 ) to compare renal outcomes with age–sex‐matched patients transplanted for chronic liver disease. This was a single‐center study of 101 patients transplanted for ALF. Fifty‐three‐and‐a‐half percent had pretransplant acute kidney injury and 64.9% required perioperative renal replacement therapy. After transplantation the 5‐year cumulative incidence of chronic kidney disease (eGFR <60 mL/min/1.73 m²) was 41.5%. There was no association between perioperative acute kidney injury (p = 0.288) or renal replacement therapy (p = 0.134) and chronic kidney disease. Instead, the independent predictors of chronic kidney disease were older age (p = 0.019), female gender (p = 0.049), hypertension (p = 0.031), cyclosporine (p = 0.027) and nonacetaminophen‐induced ALF (p = 0.039). Despite marked differences in the perioperative clinical condition and survival of patients transplanted for ALF and chronic liver disease, renal outcomes were the same. In conclusion, in patients transplanted for ALF the severity of perioperative renal injury does not predict posttransplant chronic renal dysfunction.     

Trends in Dialysis Modality for Individuals with Acute Kidney Injury

Backgrounds. There are no national level data on types of dialysis in use for acute kidney injury (AKI). We aimed to assess trends in dialysis modality for AKI and mortality associated with each modality from 1998 to 2005. Methods. Using data from the 5% Medicare cohort, we identified individuals with AKI requiring dialysis. Individuals with preexisting end-stage renal disease were excluded. Intermittent hemodialysis (IHD), daily intermittent hemodialysis, and continuous renal replacement therapy (CRRT) were defined using Current Procedure Terminology codes. Mortality was defined as death during 30 days after the first dialysis session. Results. Between 1998 and 2005, there were a total of 18,249 patients identified with AKI requiring renal replacement therapy. CRRT was increasingly used for AKI, with 9.9% of patients in 1998 to 18.3% by 2005. Proportion of daily dialysis decreased during this period, while use of IHD remained stable at approximately 68%. Overall 30-day mortality declined from 44.4% in 1998 to 40.2% in 2005. Crude mortality for CRRT was highest in all years (51.0–61.8%), followed by daily (38.2–49.9%) and IHD groups (35.8–43.4%). Multinomial logistic regression analysis showed that white race, presence of sepsis, atherosclerotic heart diseases, peripheral vascular diseases, dysrhythmia, gastrointestinal and liver diseases, and any year after 2000 were independently associated with higher odds of using CRRT after adjusting for other variables. Conclusion. The proportion of patients using CRRT has increased over time. Mortality associated with IHD has decreased from 1998 to 2005. Mortality associated with different dialysis modalities is likely the result of severity of illness.     

尿肾损伤分子-1检测对伽玛刀治疗过程中肿瘤患者发生急性肾损伤的早期诊断

目的 近年来接受立体定向伽玛射线治疗系统（伽玛刀）治疗的肿瘤患者日益增多,我们观察到部分患者在治疗过程中并发急性肾损伤（AKI）,而肿瘤患者并发AKI后病死率明显增加,因此如何早期诊断和早期干预是防治和逆转疾病进展的关键。本研究旨在观察伽玛刀治疗过程中发生AK1的肿瘤患者尿肾损伤分子-1（KIM-1）表达水平的变化及其对AKI的早期诊断价值。方法：收集我院2007年5月-2007年11月期间于伽玛刀中心入院接受体部伽玛刀治疗的100例患者的详细资料,以伽玛刀治疗过程中血清肌酐上升超过0．3mg／dl或较基础值上升〉50％为AKI的诊断标准。ELISA方法检测伽玛刀治疗过程中（造影12h、24h、48h、伽玛刀治疗7次、伽玛刀治疗结束）肿瘤患者尿KIM-1表达水平的变化。结果：所有肿瘤患者中,25例为AKI组,75例为非AKI组。在造影12h、24h、48h和伽玛刀治疗7次各时间点,AKI组尿KIM-1水平均显著高于无AKI组（P值均〈0．05）。在造影48h和治疗结束时。AKI组血肌酐水平显著高于无AKI组（P〈0．05）,而其他时间点差异无统计学意义（P〉0．05）。经尿肌酐校正后,在造影12h、24h、48h,AKI组患者尿KIM-1／尿肌酐表达水平显著高于非AKI组（P值均〈0．05）,而其他时间点差异无统计学意义（P〉0．05）。以造影12h尿KIM-1／尿肌酐表达水平诊断AKI的灵敏度和特异度绘制ROC曲线,其AUC为0．709（95％（21为0．585-0．832,P〈0．05）,与完全随机情况下获得的AUC=0．5的差异有统计学意义（P〈0．05）。结论：肿瘤患者在伽玛刀治疗过程中,造影后12h监测尿KIM-1表达水平可以较血肌酐更早期预测急性肾损伤的发生,及时检测有利于早期干预和治疗。     

Long-Term Kidney Outcomes Following Dialysis-Treated Childhood Acute Kidney Injury: A Population-Based Cohort Study

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A Multi-Center Evaluation of Early Acute Kidney Injury in Critically Ill Trauma Patients

Rationale. Few studies have evaluated the epidemiology of acute kidney injury (AKI) in trauma. Objective. To evaluate the incidence, risk factors, and outcomes associated with early AKI (evident within 24 hours of admission) in critically ill trauma patients. Methods. A retrospective interrogation of prospectively collected data from the Australian New Zealand Intensive Care Society Adult Patient Database. A total of 9,449 trauma patients were admitted for ≥24 hours to 57 intensive care units across Australia from January 1^st, 2000, to December 31^st, 2005. Main Findings. The crude incidence of AKI was 18.1% (n = 1,711). Older age, female sex (OR 1.60, 95% CI, 1.43–1.78, p < 0.0001), and the presence of co-morbid illness (OR 2.70, 95% CI 2.3–3.2, p < 0.0001) were associated with higher odds of AKI. Those with trauma not associated with brain injury (OR 2.40, 95% CI, 2.1–2.7, p < 0.0001) and a higher illness severity (OR 1.12, 95% CI, 1.11–1.12, p < 0.001) also had higher likelihood of AKI. Overall, AKI was associated with a higher crude mortality (16.7% vs. 7.8%, OR 2.36, 95% CI, 2.0–2.7, p < 0.001). Each RIFLE category of AKI was independently associated with hospital mortality in multi-variable analysis (risk: OR 1.69; injury OR 1.88; failure 2.29). Conclusions. Trauma admissions to ICU are frequently complicated by early AKI. Those at high risk for AKI appear to be older, female, with co-morbid illnesses, and present with greater illness severity. Early AKI in trauma is also independently associated with higher mortality. These data indicate a higher burden of AKI than previously described.     

Acute Kidney Injury Due to Acute Cortical Necrosis Following a Single Wasp Sting

Acute kidney injury (AKI) can develop after multiple wasp or bee stings. The etiology is the acute tubular necrosis secondary to shock, pigment toxicity, interstitial nephritis, or direct nephrotoxicity of venom. We report a 40-year-old female who presented with oliguric AKI after a single wasp sting on her hand. Her history, examination, and investigations did not support any of the established causes of AKI in such settings. She did not improve with supportive management and dialysis, and kidney biopsy showed acute cortical necrosis (ACN). This is the first report of ACN after a single wasp sting.     

Ambient Melamine Exposure and Urinary Biomarkers of Early Renal Injury

Information about environmental exposure to melamine and renal injury in adults is lacking. We investigated this relationship in 44 workers at two melamine tableware manufacturing factories in Taiwan (16 manufacturers, eight grinders, ten packers, and ten administrators) and 105 nonexposed workers (controls) at one shipbuilding company who were enrolled in August–December of 2012. For melamine workers, personal and area air samples were obtained at the worksite over 1 workweek (Monday–Friday). In the same week, pre- and post-shift one-spot urine samples were collected each workday and one first-spot urine sample was collected on each weekend morning and the following Monday morning. For each control, a one-spot urine sample was collected on Friday morning. A blood sample was also obtained from each participant at this time. Melamine levels were measured in air, urine, and serum, and early renal injury biomarkers were measured in urine. Urinary melamine concentrations in manufacturers increased sharply between pre- and post-shift measurements on Monday, remained significantly elevated throughout the workweek, and decreased over the weekend; changes in urinary melamine concentrations were substantially lower for other melamine workers. Manufacturers were exposed to the highest concentrations of ambient melamine and had significantly higher urinary and serum melamine concentrations than did the controls (P<0.001). Urinary melamine levels were positively associated with urinary N-acetyl β-d-glucosaminidase (NAG) levels but not microalbumin levels, and the detectable β2-microglobulin rate increased in the manufacturers group. In conclusion, ambient melamine exposure may increase the levels of urinary biomarkers of renal tubular injury in this occupational setting.     

PGE2, Kidney Disease,and Cardiovascular Risk: Beyond Hypertension and Diabetes

An important measure of cardiovascular health is obtained by evaluating the global cardiovascular risk, which comprises a number of factors, including hypertension and type 2 diabetes, the leading causes of illness and death in the world, as well as the metabolic syndrome. Altered immunity, inflammation, and oxidative stress underlie many of the changes associated with cardiovascular disease, diabetes, and the metabolic syndrome, and recent efforts have begun to elucidate the contribution of PGE₂ in these events. This review summarizes the role of PGE₂ in kidney disease outcomes that accelerate cardiovascular disease, highlights the role of cyclooxygenase-2/microsomal PGE synthase 1/PGE₂ signaling in hypertension and diabetes, and outlines the contribution of PGE₂ to other aspects of the metabolic syndrome, particularly abdominal adiposity, dyslipidemia, and atherogenesis. A clearer understanding of the role of PGE₂ could lead to new avenues to improve therapeutic options and disease management strategies.     

尿肾损伤分子-1预示常染色体显性多囊肾病早期发展速度

目的：探讨尿KIM-1水平与早期ADPKD患者病情进展的相关性,及其预示作用。方法：（1）收集临床确诊为ADPKD患者（CKD1,2期）及体检健康人群各40例,并取其晨起后第2次尿液标本,采用ELISA方法测定尿液中Kim-1浓度,比较多囊肾病人群与正常人群在Kim-1表达程度的差异;（2）用多囊肾患者肾脏体积增长速度判断疾病进展状况,用MRI肾脏成像的方法计算6个月间隔后肾脏体积增长情况;（3）去除肾脏总体积大于1500cm3的患者,以肾脏体积半年增长率2.7%为界,将患者划分为高平均速度组和低平均速度组,比较两组间KIM-1水平差异。结果：（1）多囊肾患者与正常人群相比,eGFR水平（采用CKD-EPI公式计算）差异无统计学意义（P〉0.05）,但尿中Kim-1水平多囊肾病组显著升高[（837.9±821.5）pg/mlvs（440.3±270.2）pg/ml,P〈0.05];（2）多囊肾患者半年肾脏体积增长速度为（4.88±3.86）%,显著高于国外报道的多囊肾患者半年体积增长速度;（3）高平均速度组KIM-1水平高于低平均速度组（P〈0.05）。结论：Kim-1作为肾小管损伤后出现的一种重要的生物标记物在多囊肾病患者群中表达显著升高,能预示早期肾脏体积并未发展到一定程度的多囊肾患者肾体积的增长快慢,但Kim-1在疾病进展中的作用机制仍需要进一步的实验研究阐明。     

前列腺素E_1治疗慢性肾脏病基础上急性肾损伤的疗效观察

目的:探讨前列腺素E1治疗在慢性肾脏病基础上急性肾损伤(A/C)的疗效。方法:将78例A/C患者分为两组,治疗组(40例)予常规治疗,并加用前列腺素E1静脉滴注,对照组(38例)予常规治疗。疗程2周,观察治疗前后两组患者肾功能和24h尿蛋白排泄量的变化,比较两组的治疗效果;同时分析A/C发生的危险因素。结果:导致A/C发生的危险因素中,两组均以严重感染、恶性高血压为多见;治疗组于治疗2周后肾功能及尿蛋白排泄量明显改善(P<0.01),而对照组仅肾功能有所改善(P<0.05),治疗组肾功能及尿蛋白排泄量改善程度比对照组明显(P<0.01)。结论:及时诊断和纠正慢性肾脏病基础上急性肾损伤的危险因素,在常规治疗基础上联合应用前列腺素E1治疗可进一步改善患者肾功能,减少尿蛋白,延缓慢性肾脏病的进展。