Understanding Of Acute Kidney Injury Research Articles

Machine learning approaches toward an understanding of acute kidney injury: current trends and future directions.

Acute kidney injury (AKI) is a significant health challenge associated with adverse patient outcomes and substantial economic burdens. Many authors have sought to prevent and predict AKI. Here, we comprehensively review recent advances in the use of artificial intelligence (AI) to predict AKI, and the associated challenges. Although AI may detect AKI early and predict prognosis, integration of AI-based systems into clinical practice remains challenging. It is difficult to identify AKI patients using retrospective data; information preprocessing and the limitations of existing models pose problems. It is essential to embrace standardized labeling criteria and to form international multi-institutional collaborations that foster high-quality data collection. Additionally, existing constraints on the deployment of evolving AI technologies in real-world healthcare settings and enhancement of the reliabilities of AI outputs are crucial. Such efforts will improve the clinical applicability, performance, and reliability of AKI Clinical Support Systems, ultimately enhancing patient prognoses.

Exploiting Machine Learning Technologies to Study the Compound Effects of Serum Creatinine and Electrolytes on the Risk of Acute Kidney Injury in Intensive Care Units.

Assessing the risk of acute kidney injury (AKI) has been a challenging issue for clinicians in intensive care units (ICUs). In recent years, a number of studies have been conducted to investigate the associations between several serum electrolytes and AKI. Nevertheless, the compound effects of serum creatinine, blood urea nitrogen (BUN), and clinically relevant serum electrolytes have yet to be comprehensively investigated. Accordingly, we initiated this study aiming to develop machine learning models that illustrate how these factors interact with each other. In particular, we focused on ICU patients without a prior history of AKI or AKI-related comorbidities. With this practice, we were able to examine the associations between the levels of serum electrolytes and renal function in a more controlled manner. Our analyses revealed that the levels of serum creatinine, chloride, and magnesium were the three major factors to be monitored for this group of patients. In summary, our results can provide valuable insights for developing early intervention and effective management strategies as well as crucial clues for future investigations of the pathophysiological mechanisms that are involved. In future studies, subgroup analyses based on different causes of AKI should be conducted to further enhance our understanding of AKI.

Characterising acute kidney injury: The complementary roles of biomarkers of renal stress and renal function.

Although epidemiological studies have enhanced our understanding of acute kidney injury, defining the biologic processes corresponding to the clinical phenotype remains challenging. We have examined biomarkers associated with renal stress plus markers of glomerular function to assess whether this approach may aid prediction of AKI or other relevant endpoints. Urinary [TIMP-2]·[IGFBP7], serum creatinine, plasma cystatin C and plasma proenkephalin 119-159 2 were analyzed in patients enrolled in the prospective, international, Sapphire study. Heterogenous critically ill patients (n = 723) were examined with a primary endpoint of development of KDIGO stage 2-3 within 12 h and a secondary endpoint of major adverse kidney events at 30 days (MAKE30). 100 patients (14%) reached the primary endpoint. Markers of renal stress outperformed those associated with glomerular function. Combining [TIMP-2]•[IGFBP7] with serum creatinine, but not the other functional markers, significantly (p = 0.02) increased the area under the ROC curve (AUC) from 0.80 (0.76-0.84) to 0.85 (0.81-0.89). In patients who did not develop AKI, all markers of glomerular filtration, but not [TIMP-2]·[IGFBP7], were significantly elevated in patients with a history of CKD (p < 0.05). The combination of cell-cycle arrest biomarkers, TIMP-2 and IGFBP7, with serum creatinine but not cystatin C or PENK improved risk stratification for the development of stage 2 or 3 AKI over [TIMP-2]·[IGFBP7] alone.

Urinary sodium excretion is low prior to acute kidney injury in patients in the intensive care unit.

The incidence of acute kidney injury (AKI) is high in intensive care units (ICUs), and a better understanding of AKI is needed. Early chronic kidney disease is associated with urinary concentration inability and AKI recovery with increased urinary solutes in humans. Whether the inability of the kidneys to concentrate urine and excrete solutes at appropriate levels could occur prior to the diagnosis of AKI is still uncertain, and the associated mechanisms have not been studied. In this single-center prospective observational study, high AKI risk in ICU patients was followed up for 7 days or until ICU discharge. They were grouped as "AKI" or "No AKI" according to their AKI status throughout admission. We collected daily urine samples to measure solute concentrations and osmolality. Data were analyzed 1 day before AKI, or from the first to the fifth day of admission in the "No AKI" group. We used logistic regression models to evaluate the influence of the variables on future AKI diagnosis. The expression of kidney transporters in urine was evaluated by Western blotting. We identified 29 patients as "No AKI" and 23 patients as "AKI," the latter being mostly low severity AKI. Urinary sodium excretion was lower in "AKI" patients prior to AKI diagnosis, particularly in septic patients. The expression of Na+/H+ exchanger (NHE3), a urinary sodium transporter, was higher in "AKI"patients. Urinary sodium excretion is low before an AKI episode in ICU patients, and high expressions of proximal tubule sodium transporters might contribute to this.

Machine Learning for Acute Kidney Injury Prediction in the Intensive Care Unit.

Machine learning is the field of artificial intelligence in which computers are trained to make predictions or to identify patterns in data through complex mathematical algorithms. It has great potential in critical care to predict outcomes, such as acute kidney injury, and can be used for prognosis and to suggest management strategies. Machine learning can also be used as a research tool to advance our clinical and biochemical understanding of acute kidney injury. In this review, we introduce basic concepts in machine learning and review recent research in each of these domains.

Inhibition of Na‐H exchanger 3 ameliorates lower limb ischemia/reperfusion‐induced acute kidney injury through preservation of mitochondrial biogenesis in mice

Despite advances in our understanding of acute kidney injury (AKI), its mortality rate remains high. Novel therapeutic targets are therefore needed. Mitochondrial dysfunction is a pivotal factor in the pathogenesis of AKI. The Na+‐H+ exchanger 3 (NHE3) plays a critical role in ATP‐dependent Na+ absorption in the proximal tubules. As such, inhibition of NHE3 may reduce metabolic demand for mitochondria thus reducing mitochondrial stress and dysfunction. In the present study, we sought to determine whether inhibition of NHE3 alleviated lower limb ischemia/reperfusion‐induced AKI. We induced lower limb ischemia/reperfusion by applying tourniquets bilaterally on the inguinal areas of male B6 or transgenic mice for 76 minutes followed by monitoring in metabolic cages for 22 hours. Control mice were treated in the same way except for no tourniquets. We used acetazolamide and kidney epithelial cell‐specific knockout to inhibit NHE3 in mice and monensin to mimic NHE3 in LLC‐PK1 cells. We assessed the renal function with urine output, transcutaneous GFR (tGFR) and serum urea nitrogen (SUN) and histology with H&amp;E staining. We measured mitochondrial biogenesis by mRNA levels of PGC‐1α, a master regulator of mitochondrial biogenesis, and its targeted genes NDUFS1 and ATP5o. Compared with the control, tourniquets reduced urinary output by 62%, tGFR by 95% and increased SUN by 774% in B6 mice. Acetazolamide, given by oral gavage (40 mg/kg), reduced NHE3 protein abundance by 37% in the kidney cortex of tourniquet‐injured mice, attenuated tourniquet‐induced reductions in urinary output by 100% and tGFR by 77%, and increase in SUN by 76%. It also attenuated tourniquet‐induced peritubular focal hemorrhage, tubular degeneration and nuclear condensation in the renal cortex. Tourniquets reduced mRNA levels of PGC‐1α, NDUFS1 and ATP5o by 45%, 44%, and 52%, respectively. Acetazolamide significantly blunted all these effects. Compared with no tourniquet‐injured mice, tourniquets reduced tGFR by 98% and increased SUN by 825% in the NHE3Flx/Flx mice, which served as a control for NHE3 knockouts. However, tourniquets only reduced tGFR by 25% and increased SUN by 105% in the kidney epithelial cell‐specific NHE3 knockouts. The difference in the effects of tourniquets between these two strains was significant (p&lt;0.05). Inhibition of NHE3 would reduce intracellular Na+concentrations. To determine whether intracellular Na+ regulates mitochondrial biogenesis, we treated LLC‐PK1 cells with monensin to raise intracellular Na+ levels. Monensin (10 μM) for 24 hours significantly reduced mRNA levels of PGC‐1α by 42%, NDUFS1 by 37% and ATP5o by 38% and activities of mitochondrial complex I by 100% and V by 58% in the cells. In conclusion, inhibition of NHE3 ameliorates tourniquet‐induced AKI through preservation of mitochondrial biogenesis, and this effect is most likely mediated by reducing intracellular Na+ concentration.

POS-821 AN ACUTE KIDNEY INJURY EDUCATION PROGRAMME FOR INTERNATIONAL MEDICAL ELECTIVE STUDENTS IN THE UK

Medical electives are a core part of the medical school curriculum and provide an opportunity for medical students to experience another culture and study medicine in another country. However, there is little information available on the development of teaching programmes for elective students. An innovative teaching programme was developed for 21 visiting medical elective students from 12 different countries who were placed across a range of clinical specialties in a large UK Teaching Hospital. Over the course of a four week placement, students were timetabled to attend weekly teaching sessions in the Undergraduate Medical Education Centre. The first session was designed to allow the students to discuss their different backgrounds and educational experiences as well as understand their aims for the placements. A personalised teaching programme was then developed centred around some of their expectations with a focus on acute kidney injury (AKI). The teaching sessions included interactive lectures, clinical skills and simulation teaching. The nature of any prior teaching they had received on AKI in their home institutions was established and pre- and post-teaching questionnaires were completed to explore the confidence of students across a range of domains. These included understanding of the risk factors, causes, assessment and management of patients with AKI as well as recognition and management of the complications of this condition. The medical students had received variable preparation for their elective from their home institutes prior to travelling. The aims of the elective students varied greatly and included experiencing a different healthcare system, developing their English language skills and exploring specialties of interest. All students had previously received teaching on AKI; this was delivered at some stage between the second and the final year of their studies at their home university. Similarly, there was considerable variation as to when students had their first patient contact, also ranging from the second to the final year of their medical degree. The majority of students (63%) had received teaching on AKI using a mix of modalities including lectures, tutorials and teaching on clinical placements. The remaining students received lectures only. Pre- and post- teaching questionnaires indicated that confidence levels improved across all domains following the teaching sessions on AKI compared to confidence levels prior to this. Feedback was positive with all sessions rated ‘good’ or ‘excellent’. Evaluation of the elective placements demonstrated the value placed by students on the teaching sessions in not only improving their knowledge and clinical skills but also in developing their understanding of the healthcare system and gaining confidence. The teaching programme supported them in meeting some of their aims, which may not have been possible otherwise. In conclusion, the acute kidney injury elective student teaching programme allowed visiting students to meet other students in a protected and relaxed environment. The students were able to determine their aims and maximise the learning opportunities available to them during their elective placement. Finally, the students’ clinical skills and understanding of AKI also improved as a result of the teaching programme.

KNOWLEDGE ON ACUTE KIDNEY INJURY AMONG NURSES WORKING IN A TERTIARY HOSPITAL

Background: Nurses can play a pivotal role to identify and prevent acute kidney injury (AKI) at the earliest and their level of understanding about the disease remains quite important. So, this study was conducted with an aim of assessing the level of understanding of AKI among nurses. Methods: A cross-sectional descriptive study was conducted among 122 nursing staffs working at different wards of a tertiary hospital. Knowledge on AKI was evaluated on different headings-definition, risk factors, bed side nursing observations, and supportive care. Semi-structured ques­tionnaire was used to collect the responses through self-administered method. Analysis was done through frequency, percentage median, chi-square test and through odds ratio using Microsoft Excel and SPSS version 16 for windows. Results: A total of 122 nurses were included in the study. Mean age of the respondents was 26.7±5.88 years. Only 43.4% of the respondents could correctly define AKI on the basis of creati­nine value. Non-steroidal anti-inflammatory drugs (NSAIDs) and aminoglycosides as nephrotoxic drugs could be listed by 59.8% and 23.7% of the respondents respectively. About 40% of the nurses mentioned the requirement of observation of both intake and output as a part of management of AKI. Overall, 53.3% of the nurses were found to have an inadequate knowledge of AKI. Conclusions: Inadequate knowledge of AKI among nurses can hinder the early recognition and management. Therefore, there seems to be a strong need of formal and structured refreshing course for the nurses to provide current updates on identification, risk assessment, recognition and response of AKI.

An escape room simulation focused on renal-impairment for prelicensure nursing students

The goal of a hands-on approach to present concepts in nursing curricula is to prepare graduates to meet the demands of professional practice. This teaching and learning project incorporated an interactive methodology for teaching associate degree nursing students. A needs analysis revealed a lack of understanding of acute kidney injury. To address this gap, learners completed an escape room, utilizing Kolb's experiential learning theory. Learners were students enrolled in the third semester of an associate degree registered nursing program. Five of the eight student groups successfully escaped, and the mean score of the post-test increased to 86% from a pretest mean of 73.5%. Students found the activity to be a fun way to apply their knowledge. Results indicate escape rooms help prepare students for future practice. Using gamification strategies increases student learning, promotes learner socialization, and builds confidence.

Real-time glomerular filtration rate: improving sensitivity, accuracy and prognostic value in acute kidney injury.

Acute kidney injury (AKI) is common and associated with high patient mortality, and accelerated progression to chronic kidney disease. Our ability to diagnose and stratify patients with AKI is paramount for translational progress. Unfortunately, currently available methods have major pitfalls. Serum creatinine is an insensitive functional biomarker of AKI, slow to register the event and influenced by multiple variables. Cystatin C, a proposed alternative, requires long laboratory processing and also lacks specificity. Other techniques are either very cumbersome (inuline, iohexol) or involve administration of radioactive products, and are therefore, not applicable on a large scale. The development of two optical measurement techniques utilizing novel minimally invasive techniques to quantify kidney function, independent of serum or urinary measurements is advancing. Utilization of both one and two compartmental models, as well as continuous monitoring, are being developed. The clinical utility of rapid GFR measurements in AKI patients remains unknown as these disruptive technologies have not been tested in studies exploring clinical outcomes. However, these approaches have the potential to improve our understanding of AKI and clinical care. This overdue technology has the potential to individualize patient care and foster therapeutic success in AKI.

Acute kidney injury, its definition, and treatment in adults: guidelines and reality.

In the last decades, a lot of research has been done to improve our understanding of acute kidney injury (AKI) as well to standardize its diagnostic criteria. As a result of many years of work of intensivists and nephrologists, consensus definitions were established, finally unified in 2012 by the Kidney Disease: Improving Global Outcomes (KDIGO) group. These criteria refer to the time of AKI development and are based on serum creatinine level increase and / or urine output decrease. Acute kidney injury is defined as an increase in serum creatinine levels by at least 0.3 mg/dl within 48 hours or 1.5‑fold the baseline, which is known or presumed to have occurred within the preceding 7 days, or-according to the urine output criterion-urine volume less than 0.5 ml/kg/hour for at least 6 hours. The present review covers issues discussed during the KDIGO controversy conference, devoted to AKI. Here, we attempted to answer 3 main questions: Is the KDIGO definition of AKI valuable in clinical research and global epidemiology? Is it helpful in everyday clinical practice? Is it useful in the treatment of critically ill patients with AKI?

Big Data and Pediatric Acute Kidney Injury: The Promise of Electronic Health Record Systems.

Over the last decade, our understanding of acute kidney injury (AKI) has evolved considerably. The development of a consensus definition standardized the approach to identifying and investigating AKI in children. As a result, pediatric AKI epidemiology has been refined and the consequences of renal injury are better established. Similarly, “big data” methodologies experienced a dramatic evolution and maturation, leading the critical care community to explore potential AKI/big data synergies. One such concept with tremendous potential is electronic health record (EHR) enabled informatics. Much of the promise surrounding these approaches is due to the unique position of the EHR which sits at the intersection of data accumulation and care delivery. EHR data is generated simply via the provision of routine clinical care and should be considered “big” from the standpoint of volume, variety, and velocity as a myriad of diverse elements accumulate rapidly in real time, spontaneously generating an immense dataset. This massive dataset interfaces directly with providers which creates tremendous opportunity. AKI can be diagnosed more accurately, AKI-related care can be optimized, and subsequent outcomes can be improved. Although applying big data concepts to the EHR has proven more challenging than originally thought, we have seen much success and continue to explore its potential. In this review article, we will discuss the EHR in the context of big data concepts, describe approaches applied to date, examine the challenges surrounding optimal application, and explore future directions.

Neonatal and Paediatric Heart and Renal Outcomes Network: design of a multi-centre retrospective cohort study.

Cardiac surgery-associated acute kidney injury is common. In order to improve our understanding of acute kidney injury, we formed the multi-centre Neonatal and Pediatric Heart and Renal Outcomes Network. Our main goals are to describe neonatal kidney injury epidemiology, evaluate variability in diagnosis and management, identify risk factors, investigate the impact of fluid overload, and explore associations with outcomes. The Neonatal and Pediatric Heart and Renal Outcomes Network collaborative includes representatives from paediatric cardiac critical care, cardiology, nephrology, and cardiac surgery. The collaborative sites and infrastructure are part of the Pediatric Cardiac Critical Care Consortium. An acute kidney injury module was developed and merged into the existing infrastructure. A total of twenty-two participating centres provided data on 100-150 consecutive neonates who underwent cardiac surgery within the first 30 post-natal days. Additional acute kidney injury variables were abstracted by chart review and merged with the corresponding record in the quality improvement database. Exclusion criteria included &gt;1 operation in the 7-day study period, pre-operative renal replacement therapy, pre-operative serum creatinine &gt;1.5 mg/dl, and need for extracorporeal support in the operating room or within 24 hours after the index operation. A total of 2240 neonatal patients were enrolled across 22 centres. The incidence of acute kidney injury was 54% (stage 1 = 31%, stage 2 = 13%, and stage 3 = 9%). Neonatal and Pediatric Heart and Renal Outcomes Network represents the largest multi-centre study of neonatal kidney injury. This new network will enhance our understanding of kidney injury and its complications.

Acute Kidney Stress and Prevention of Acute Kidney Injury.

Critical care physicians continue to be challenged to recognize an environment that has the potential to result in acute kidney injury, with its associated short- and long-term consequences. The recent development of cell cycle arrest biomarkers that signal the potential development of acute kidney injury is part of an evolution in the molecular diagnosis and understanding of acute kidney injury. A preinjury phase that may lead to acute kidney injury has been described as "acute kidney stress." This concept has the potential to stimulate research and innovation that will lead to early implementation of measures to prevent or reverse acute kidney injury.

Acute Kidney Injury during Pediatric Vaso-Occlusive Crisis

Several potential risk factors are being evaluated for their impact on the development of chronic kidney disease (CKD) in patients with Sickle Cell Disease (SCD). Recent studies in animals, children and adults without SCD, have established that acute kidney injury (AKI) can lead to CKD, yet the risk of repeated AKI events during vaso-occlusive crisis (VOC) has not been defined in SCD. During VOC events, patients may be at risk for developing AKI due to the use of nephrotoxic pain medications, dehydration (poor concentrating ability), hemolysis, or inflammatory responses. Multiple gaps in our understanding of AKI in SCD patients need to be addressed.Methods: In order to improve our understanding of the incidence, risk factors, and outcomes associated with AKI, we conducted a two year IRB approved retrospective review of 234 episodes of ICD-10 defined VOC admitted from Children’s of Alabama Pediatric Emergency Department (ED). AKI was defined by KDIGO definition of an increase in serum creatinine (SCr) by ≥ 0.3 mg/dl or 50% increase in serum creatinine from baseline. Baseline labs were defined as the most recent outpatient laboratory value and within 12 months from admission. Thirty seven admissions were excluded as their baseline SCr could not be established. Variables analyzed included age, gender, SCD genotype, baseline and admission CBC (hemoglobin (Hb) value, white blood cell count (WBC), absolute neutrophil count (ANC), platelet count, and absolute reticulocyte count (ARC)), length of stay (LOS), and SCD modifying therapy. Generalized mixed effects model for binary outcome with random intercept, to accommodate repeated hospitalizations for the same subject, was fitted to assess the associations between clinical variables and AKI for all patients and severe phenotypes. Similarly, a generalized mixed Poisson effects model with random intercept was fitted to determine if AKI was independently associated with hospital length of stay.Results: Among 197 admissions for VOC, 33 (17%) were identified with AKI. Seventeen (52%) of the thirty three AKI events were first diagnosed in the ED. Compared to children without AKI, patients with AKI had a larger drop in hemoglobin from baseline at admission (0.5 vs. 1.21g/dL, p=0.005). For every 1 unit drop in Hb from baseline to admission, the odds of AKI increased by 49% (OR= 1.49, 95% CI 1.1-2.0). We identified no differences in AKI vs. no AKI by age, gender, SCD genotype, or SCD modifying therapy, change in WBC, ANC, Platelets or absolute reticulocyte count. In multivariate analysis accounting for age, gender, change in blood counts, SCD genotype or therapy, a drop in Hb remained the only significant variable (OR= 1.48, 95% CI 1.05-2.1). Patients with AKI admitted for vaso-occlusive crisis required significantly longer length of stay. The average LOS for those with AKI was 32% longer than the without AKI (OR 1.32, 95% CI 1.10-1.58).Conclusion: Seventeen percent of SCD patients with pain admitted to the hospital can present with or develop AKI. An acute drop in hemoglobin is a major risk factor for developing AKI. Patients that develop AKI require longer hospitalizations for their pain crisis, independent of potential confounders. Research should focus on pathophysiology of kidney injury in patients with SCD, the impact of nephrotoxic medications, and the role by which AKI leads to CKD in this population. DisclosuresAskenazi:AKI foundation: Consultancy, Speakers Bureau; BTG: Consultancy, Speakers Bureau; Alexion: Consultancy, Speakers Bureau; Baxter: Consultancy, Speakers Bureau. Lebensburger:American Society of Hematology, Scholar Award: Research Funding; National Institutes of Health: Research Funding.

Why are patients still getting and dying from acute kidney injury?

Acute kidney injury is common and is associated with increased morbidity and mortality. Rates of acute kidney injury in most settings remain high and in some settings are increasing. Moreover, outcomes associated with acute kidney injury remain relatively poor. This review focuses on recent advances in understanding of acute kidney injury and discusses possible interventions based on these advances. Acute kidney injury is not a disease with a single etiology and clinical course but rather a loose collection of syndromes whose unifying phenotype is an acute loss of glomerular filtration. Traditional taxonomy based on anatomic locations (pre, intra, and post) in reference to the kidney is overly simplistic and has given way to specific 'endotypes' including hepatorenal, cardiorenal, nephrotoxic, and sepsis-associated and these syndromes all have unique pathophysiologies and treatments. Our tendency to lump all of these clinical syndromes into a single disease and seek a single treatment has led to the profound lack of progress observed in terms of improving outcomes. The hope is that this is about to change. Understanding the epidemiology, pathogenesis, and pathophysiology of acute kidney injury is critical to achieving improved outcomes for the millions of patients who develop this loose constellation of syndromes.

Early lipid changes in acute kidney injury using SWATH lipidomics coupled with MALDI tissue imaging

Acute kidney injury (AKI) is one of the leading causes of in-hospital morbidity and mortality, particularly in critically ill patients. Although our understanding of AKI at the molecular level remains limited due to its complex pathophysiology, recent advances in both quantitative and spatial mass spectrometric approaches offer new opportunities to assess the significance of renal metabolomic changes in AKI models. In this study, we evaluated lipid changes in early ischemia-reperfusion (IR)-related AKI in mice by using sequential window acquisition of all theoretical spectra (SWATH)-mass spectrometry (MS) lipidomics. We found a significant increase in two abundant ether-linked phospholipids following IR at 6 h postinjury, a plasmanyl choline, phosphatidylcholine (PC) O-38:1 (O-18:0, 20:1), and a plasmalogen, phosphatidylethanolamine (PE) O-42:3 (O-20:1, 22:2). Both of these lipids correlated with the severity of AKI as measured by plasma creatinine. In addition to many more renal lipid changes associated with more severe AKI, PC O-38:1 elevations were maintained at 24 h post-IR, while renal PE O-42:3 levels decreased, as were all ether PEs detected by SWATH-MS at this later time point. To further assess the significance of this early increase in PC O-38:1, we used matrix-assisted laser desorption ionization imaging mass spectrometry (MALDI-IMS) to determine that it occurred in proximal tubules, a region of the kidney that is most prone to IR injury and also rich in the rate-limiting enzymes involved in ether-linked phospholipid biosynthesis. Use of SWATH-MS lipidomics in conjunction with MALDI-IMS for lipid localization will help in elucidating the role of lipids in the pathobiology of AKI.

Acute kidney stress--a useful term based on evolution in the understanding of acute kidney injury.

Critical care physicians have debated an appropriate term for the clinical phase preceding acute kidney injury (AKI). The recent development of cell cycle arrest biomarkers that signal the potential development of AKI is part of an evolution in the molecular diagnosis and understanding of AKI. It is proposed that the pre-injury phase that leads to AKI can be described as “acute kidney stress”. This term has the potential to expand horizons in regard to the early detection of situations that will lead to AKI and the early implementation of corrective measures.

Long-Term Mortality among Hospitalized Non-ICU Patients with Acute Kidney Injury Referred to Nephrology

Background: Epidemiological studies of acute kidney injury (AKI) have focused on patients admitted to intensive care units (ICUs), and several have studied hospitalized non-ICU patients, but analysis of patients referred to Nephrology is sparse. We analyzed factors associated with short- and long-term morbimortality among hospitalized non-ICU patients with AKI who were referred to Nephrology. Methods: A retrospective study with data prospectively collected from 170 non-ICU patients, with referral to the Nephrology Unit, recruited over a 4-year period, was performed. AKI was classified according to the criteria based on risk, injury, failure, loss of kidney function and end-stage kidney disease (RIFLE). Risk factors that could influence prognosis of AKI and long-term mortality were analyzed at admission. Early on, 1- and 10-year mortalities were correlated with AKI RIFLE class, clinical and demographic characteristics. Results: Most patients were >65 years, with multiple comorbidities and frequent drug intake history. Median Charlson score was 6. Twenty-five percent of patients with previously unknown chronic kidney disease (CKD) were diagnosed with CKD during the study. Dialysis was required in 13.5% of patients. Hospital deaths were 22.4% and significantly associated with older age, RIFLE class L, higher peak serum creatinine, oliguria and decreased serum albumin levels. One-year (38.8%) and 10-year (68.8%) mortalities were significantly associated with age, prior cardiovascular disease, prior CKD and RIFLE class L. According to the Cox proportional hazard model, age, prior CKD and RIFLE class L were independent risk factors of death at 1 and 10 years. Conclusions: AKI in hospitalized non-ICU patients is associated with high early and late mortality. This study increases our understanding of AKI among this specific population and can improve their management.

Neonatal Acute Kidney Injury.

In recent years, there have been significant advancements in our understanding of acute kidney injury (AKI) and its impact on outcomes across medicine. Research based on single-center cohorts suggests that neonatal AKI is very common and associated with poor outcomes. In this state-of-the-art review on neonatal AKI, we highlight the unique aspects of neonatal renal physiology, definition, risk factors, epidemiology, outcomes, evaluation, and management of AKI in neonates. The changes in renal function with gestational and chronologic age are described. We put forth and describe the neonatal modified Kidney Diseases: Improving Global Outcomes AKI criteria and provide the rationale for its use as the standardized definition of neonatal AKI. We discuss risk factors for neonatal AKI and suggest which patient populations may warrant closer surveillance, including neonates <1500 g, infants who experience perinatal asphyxia, near term/ term infants with low Apgar scores, those treated with extracorporeal membrane oxygenation, and those requiring cardiac surgery. We provide recommendations for the evaluation and treatment of these patients, including medications and renal replacement therapies. We discuss the need for long-term follow-up of neonates with AKI to identify those children who will go on to develop chronic kidney disease. This review highlights the deficits in our understanding of neonatal AKI that require further investigation. In an effort to begin to address these needs, the Neonatal Kidney Collaborative was formed in 2014 with the goal of better understanding neonatal AKI, beginning to answer critical questions, and improving outcomes in these vulnerable populations.