Acute kidney injury: risk factors and management challenges in developing countries

The role of endothelin receptor antagonists in kidney disease

Kidney diseases are among the most prevalent conditions worldwide, impacting over 850 million individuals. They are categorized into acute kidney injury and chronic kidney disease. Current preclinical and clinical trials have demonstrated that endothelin (ET) is linked to the onset and progression of kidney disease. In kidney diseases, pathological conditions such as hyperglycemia, acidosis, insulin resistance, and elevated angiotensin II levels lead to an increase in ET. This elevation activates endothelin receptor type A, resulting in harmful effects like proteinuria and a reduced glomerular filtration rate (GFR). Therefore, to slow the progression of kidney disease, endothelin receptor antagonists (ERAs) have been proposed as promising new therapies. Numerous studies have demonstrated the efficacy of ERAs in significantly reducing proteinuria and improving GFR, thereby slowing the progression of kidney diseases. This review discusses the mechanisms of action of ERAs in treating kidney disease, their efficacy and safety in preclinical and clinical studies, and explores future prospects for ERAs.

Myrtenal Pretreatment Exerts a Protective Effect Against Renal Ischemia-Reperfusion Injury in Rats

Acute kidney injury (AKI) is a serious condition with high mortality in intensive care units and during vascular surgeries. Renal ischemia-reperfusion injury (IRI) significantly contributes to AKI. Preclinical studies have shown that myrtenal (Myrt) has anti-inflammatory and antioxidant properties. We hypothesized that Myrt might alleviate renal damage caused by IRI through the modulation of oxidative stress and inflammatory processes. This study aimed to investigate the renoprotective potential of Myrt against IRI using biochemical evaluations and histological examinations. Forty male Sprague Dawley rats were assigned to four groups: sham, IRI, Myrt40+IRI, and Myrt80+IRI. Animals received daily intraperitoneal injections of Myrt (40-80 mg/kg) or solvent for 9 days before surgery. The sham group underwent laparotomy, while the other groups had AKI induced via bilateral renal pedicle clamping for 45 min, followed by 24 h of reperfusion. Renal function was assessed by blood urea nitrogen (BUN), creatinine, kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) levels. Inflammatory markers interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α) were measured, along with oxidative stress parameters malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH). Renal damage was evaluated histopathologically using hematoxylin and eosin staining and apoptosis was assessed via caspase-3 immunohistochemistry. In the IRI group, serum BUN and creatinine levels were significantly higher than the sham group but were reduced by Myrt pretreatment (p < 0.05). IRI also led to significant increases in MDA, KIM-1, NGAL, IL-1β, and TNF-α in kidney tissue (p < 0.05), which were notably decreased by Myrt pretreatment (p < 0.05). Myrt also restored SOD and CAT enzyme activities and GSH levels reduced by IRI (p < 0.05). Histological analysis showed Myrt significantly alleviated renal tissue damage and reduced caspase-3 immunoreactivity due to IRI (p < 0.05). The findings suggest that Myrt has a protective effect against renal IRI.

Impact of Non-Dialysis-Requiring Acute Kidney Injury on Survival Outcomes in Non-critically Ill Hospitalized Medical Patients in a Resource-Limited Setting: A Retrospective Cohort Study

Introduction The severe consequences of acute kidney injury (AKI) have been well-documented in high-risk patient populations. However, the effects of milder forms in non-critically ill patients remain understudied, particularly in resource-limited settings. While the risk of mortality associated with these cases is considered low, it can still lead to various complications including prolonged hospitalization, which may influence long-term renal and patient survival. Hence, the objective of this study was to study the impact of non-dialysis-requiring AKI (NDR-AKI) on survival outcomes of non-critically ill medical patients admitted to St. Paul's Hospital Millennium Medical College in Ethiopia during the period from July 2019 to January 2022. Methods A retrospective cohort study was conducted among 300 non-critically ill medical patients, 93 with NDR-AKI and 207 without AKI. Descriptive statistics, including frequency distributions and median survival times, were employed to summarize the data. Kaplan-Meier curves and the log-rank test were utilized to compare survival experiences of groups. A Cox proportional hazards survival model was fitted to estimate the impact of NDR-AKI on time to recovery. Adjusted hazard ratio (AHR) with 95% confidence interval (CI) was used to report findings. Results Two hundred four (68.0%) were discharged after improvement and the median recovery time was 16 days (95%CI: 13.5-18.5 days). Having NDR-AKI was associated with a 43% lower rate of achieving recovery (AHR=0.57, 95%CI=0.38, 0.84, p-value=0.004). Females were found to have a 1.41 times higher rate of recovery (AHR=1.41, 95%CI=1.03,1.94, p-value=0.033). Additionally, having tuberculosis (AHR=0.41, 95%CI=0.23,0.72, p-value=0.002) and being on anticoagulant (AHR=0.67, 95%CI=0.47,0.95, p-value=0.027) were associated with a 59% and 33% lower rate of recovery, respectively. Conclusion NDR-AKI significantly delays recovery compared to patients without AKI suggesting that even milder forms of AKI in non-critically ill patients can negatively impact patient outcomes. Early identification, prompt management, and addressing underlying causes are key to improving recovery and reducing long-term morbidity and mortality. Strict screening and monitoring of high-risk groups such as men, patients with tuberculosis, and those on anticoagulants is also crucial.

A Comparative Study of Community-acquired Acute Kidney Injury and Hospital-acquired Acute Kidney Injury from a Tertiary Care Hospital in North India

BACKGROUND

In this observational study, clinical characteristics, etiologies, and outcomes of patients admitted to the hospital with community-acquired acute kidney injury (CAAKI) have been compared in contrast to those who hospital-acquired Acute Kidney Injury (HAAKI).

METHODS

This was a prospective study of adults aged 18 years or above diagnosed with acute kidney injury (AKI) over a period of 17 months at a tertiary care hospital.

RESULTS

230 patients had AKI with the mean age of the study population being 45.33 ± 12.68 years. 178 (77.4%) patients were enrolled from medical unit, 25 (10.7%) from surgical unit, and 27 (11.7%) from obstetrical unit. The observed incidence of AKI was 15/1000 admissions. About 58.2% had CAAKI and 96 (43.7%) had HAAKI. Out of 230 patients, 170 (73.9%) patients were male and 60 (26.1%) were female. Sepsis was the most common (52.1%) etiology of AKI among the medical cases. Urosepsis, scrub typhus, and pneumonia were the most common causes of AKI. Sixty percent of AKI was Kidney Disease Improving Global Outcomes Stage 1 or 2 and 40% was in Stage 3. Oliguria was seen in 56.5%, hyperkalemia in 34.7%, fluid overload in 6.1%, and metabolic acidosis in 22.6%. The majority of patients had multiple organ involvement (52.1%) at the time of enrollment. About 116 (50.4%) had lung injury requiring mechanical ventilation and 95 (41.3%) were on inotropes. Mortality occurred in 19.5%. Anemia, the use of vasopressor drugs, and the need for intensive care support were independent predictive factors for mortality.

CONCLUSION

AKI was common in hospitalized patients and leads to significant inhospital mortality. AKI is largely a CAAKI, and the lesser extent is due to HAAKI. Many causes are potentially preventable. Early fluid resuscitation, effective antibiotics, appropriate antidotes, and timely referral of established AKI patients to centers with dialysis facilities can improve AKI outcomes.

Hospital-Acquired Acute Kidney Injury in Non-Critical Medical Patients in a Developing Country Tertiary Hospital: Incidence and Predictors

Background

Acute kidney injury (AKI) is a frequent complication in critical patients, leading to a worse prognosis. Although its consequences are worse among critical patients, AKI is also associated with less favorable outcomes in non-critical patients. Therefore, understanding the magnitude of the problem in these patients is crucial, yet there is a scarcity of evidence in non-critical settings, especially in resource limited countries. Hence, the study aimed at determining the incidence and predictors of hospital acquired acute kidney injury (HAAKI) in non-critical medical patients who were admitted at a large tertiary hospital in Ethiopia.

Methods

A retrospective chart review study was conducted from September 25, 2022 to January 20, 2023 among 232 hospitalized non-critical medical patients admitted to St. Paul's Hospital Millennium Medical College between January 2020 and January 2022. The incidence of HAAKI was estimated using incidence density per total person day (PD) observation of the study participants. To identify predictors of HAAKI, a log binomial regression model was fitted at a p value of ≤0.05. The magnitude of association was measured using adjusted relative risk (ARR) with its 95% CI.

Results

During the median follow-up duration of 11 days (IQR, 6-19 days), the incidence of HAAKI was estimated to be 6.0 per 100 PD (95% CI = 5.5 to 7.2). Significant predictors of HAAKI were found to be having type 2 diabetes mellitus (ARR = 2.36, 95% CI = 1.03, 5.39, p-value=0.042), and taking vancomycin (ARR = 3.04, 95% CI = 1.38, 6.72, p-value=0.006) and proton pump inhibitors (ARR = 3.80, 95% CI = 1.34,10.82, p-value=0.012).

Conclusion

HAAKI is a common complication in hospitalized non-critical medical patients, and is associated with a common medical condition and commonly prescribed medications. Therefore, it is important to remain vigilant in the prevention and timely identification of these cases and to establish a system of rational prescribing habits.

Galectin-3 and Autophagy in Renal Acute Tubular Necrosis

Acute kidney injury (AKI) is a public health burden with increasing morbidity and mortality rates and health care costs. Acute tubular necrosis (ATN) is the most common cause of AKI. Cisplatin (CIS) is a platinum-based chemotherapeutic agent used in the treatment of a wide variety of malignancies such as lung, breast, ovary, testis, bladder, cervix, and head and neck cancers. Autophagy plays an important role in AKI. Galectin-3 (Gal-3) is significantly increased in renal tubules in AKI; however, its role in autophagy is not well understood. Male C57B6/J and B6.Cg-Lgals3 /J Gal-3 knockout (KO) mice were used to induce AKI using a CIS mouse model of ATN. Renal Gal-3 and autophagy proteins' expression were measured using standard histologic, immunofluorescent, and enzyme-linked immunosorbent assay techniques. The data were presented as the mean ± S.E. Statistically significant differences (p < 0.05) were calculated between experimental groups and corresponding control groups by one-way analysis of variance. There was a significant increase in renal concentrations of Gal-3 in the Gal-3 wild-type CIS-treated mice when compared with sham control mice. There were significantly higher concentrations of renal LC3B, ATG13, Ulk-1, Beclin, ATG5, ATG12, ATG9A, and p-AMPK in the CIS-treated Gal-3 KO mice than in the Gal-3 wild-type CIS-treated mice. Further, there were significantly higher concentrations of mTOR, p- NF-κB, beta-catenin, and p62 in the kidneys of the Gal-3 wild-type CIS-treated mice than in the Gal-3 KO CIS-treated mice. Our findings affirm the connection between Gal-3 and autophagy, revealing its central role as a connector with prosurvival signaling proteins. Gal-3 plays a pivotal role in orchestrating cellular responses by interacting with prosurvival signal pathways and engaging with autophagy proteins. Notably, our observations highlight that the absence of Gal-3 can enhance autophagy in CIS-induced ATN.

Implications of climate change on acute kidney injury

PURPOSE OF REVIEW

Climate change is an active and growing threat to human health. This review examines the evidence linking climate change to kidney diseases, with a focus on acute kidney injury (AKI).

RECENT FINDINGS

A growing body of evidence documents the adverse impact of various environmental and occupational exposures on kidney health. Extreme heat exposure increases the risk for AKI in vulnerable populations, particularly outdoor workers. These effects are being seen in both developed and developing nations, impacting equatorial as well as more northern climates. Climate change is also increasing the risk of water-borne and vector-borne infections, which are important causes of AKI in tropical regions. Due to overlapping environmental and social risk factors, populations in low-income and middle-income countries are likely to be disproportionately affected by climate-related health impacts, including heightened risk for kidney diseases.

SUMMARY

Climate change will adversely impact global kidney health over the course of the century through effects on temperature and risk of endemic infections. Alongside efforts to aggressively reduce carbon emissions, additional research is needed to guide public and environmental health policies aimed at mitigating the impact of climate change on human health.

Burden and Risk Factors of Contrast-Associated Acute Kidney Injury in Hospitalized Zambian Children: A Prospective Cohort Study at the University Teaching Hospitals

Background

Contrast-associated acute kidney injury (CAAKI) is defined as acute kidney injury (AKI) occurring within 72 hours of administration of contrast media (CM) and is linked to adverse outcomes including longer hospital stay, increased hospital mortality, and a higher risk of chronic kidney disease in later life. Risk factors for the development of CAAKI in the Zambian pediatric population have not been well studied.

Objectives

The objective of this study was to assess the burden of CAAKI, ascertain its risk factors, and describe short-term outcomes in hospitalized children at the University Teaching Hospitals (UTH) undergoing contrast-enhanced radiological investigations.

Methods

This was a prospective observational study of in-patients undergoing contrast-enhanced radiological procedures, between September 2020 and September 2021. The participants were recruited from the Children's Hospital, the Cancer Diseases Hospital, and the Pediatric Surgical Ward at the University Teaching Hospital in Lusaka, Zambia. The primary outcome variable was occurrence of AKI at 48 hours post CM administration. We used 2 criteria to define CAAKI in our study-the European Society of Urogenital Radiology (ESUR) and the Kidney Disease Improving Global Outcomes (KDIGO) 2012 criteria. Multivariable logistic regression models were formulated to assess for risk factors of CAAKI.

Results

Of the 201 enrolled participants, 123 (61.2%) were male and the median age of the participants was 5 years (interquartile range [IQR] = 3-10). The mean hemoglobin was 103 g/L (standard deviation [SD] = 26), median creatinine was 30.9 µmol/l (IQR = 22.6-43), and the glomerular filtration rate (GFR) was 102.5 mL/min/1.73 m2 (IQR = 76.2-129.4). Forty-six (22.9%) developed CAAKI using the ESUR compared with 4.5% (9/201) using the KDIGO criteria. Independent risk factors of CAAKI were receiving a higher dose of CM (adjusted odds ratio [aOR] = 2.54; 95% confidence interval [CI] = [1.12-5.74]), prematurity (aOR = 4.6; 95% CI = [1.05-16.7]), and a higher eGFR (aOR= 1.01; 95% CI = [1.01-1.02]). Females had higher odds of CAAKI (aOR = 2.48; 95% CI = [1.18-5.18]) when compared with males. One CAAKI participant (2.2%) died; none of the participants who developed CAAKI and survived required dialysis and most of them (90%) were discharged before day 7. Day 7 eGFR results had returned to or near baseline values for those whose creatinine results were available.

Conclusions

Using the ESUR criteria, a significant proportion (22.9%) of children undergoing contrast-enhanced computed tomography (CT) scans at the UTH developed CAAKI. In contrast, using the KDIGO criteria only 4.5% had CAAKI. Being born as a preterm baby, being female, having a higher eGFR at baseline, and receiving a higher dose of CM were found to be independent risk factors for CAAKI development in Zambian children. Most of the cases of CAAKI in children were transient and of little clinical significance as only a minority of patients developing CAAKI required kidney replacement therapy and all resolved by day 7 post administration of CM.

Access to Nephrology Care for Pregnancy-Related Acute Kidney Injury in Low- and Lower-Middle-Income Countries: A Perspective

Pregnancy-related acute kidney injury (AKI) is a major public health problem with substantial maternal and fetal morbidity and mortality. Women with pregnancy-related AKI require immediate access to nephrology care to prevent deleterious kidney and health outcomes. Patients with pregnancy-related AKI in low-income and lower-middle-income countries experience disparities in access to comprehensive nephrology care for many reasons. In this perspective, we highlight the burden of pregnancy-related AKI and explore the challenges among different low-income and lower-middle-income countries. The lack of adequate nephrology workforce and infrastructure for kidney health care represents a fundamental component of the problem. A shortage of nephrologists hampers the care of patients with pregnancy-related AKI leading to poor outcomes. The lack of diagnostic tools and therapeutic options, including kidney replacement therapy, impedes the implementation of effective management strategies. International efforts are warranted to empower women to get the right services and support at the right time. Dedicated preventive and early care programs are urgently needed to decrease the magnitude of pregnancy-related AKI, a complication under-represented in the literature.

Peritoneal dialysis: An effective therapeutic modality in acute kidney injury

Background

Peritoneal dialysis (PD) as a modality of renal replacement therapy (RRT) in acute kidney injury (AKI), continues to be underused. We present our experience with PD in patients with AKI.

Method

The data of patients with AKI requiring RRT were retrospectively analyzed. The primary end point was the adequacy of dialysis, and the secondary end point included hemodynamic stability and procedure-related complications.

Result

A total of 32 patients with AKI requiring RRT were included in the study. The mean age and the blood pressure at the time of hospitalization were 65.3 ± 6.73 years and 73.7 ± 8.4 mm Hg, respectively. All the patients required vasopressor support; 26 (81%) patients required ventilator support. RRT was initiated at a mean serum creatinine of 6.24 ± 1.17 mg/dL. Rigid stylet catheter was used in 9 (28.2%) and Tenckhoff catheter in 23 (71.8%) patients. The average daily ultrafiltration and weekly Kt/V achieved were 1701 ± 327 mL and 2.19, respectively; these were significantly higher in survivors. After the initiation of PD, hemodynamic instability was observed in 10 (31.2%) patients. The major therapy-related complication noted was PD peritonitis.

Conclusions

In a resource-poor environment, PD is an effective modality of RRT for AKI.

Inflammatory mediators act at renal pericytes to elicit contraction of vasa recta and reduce pericyte density along the kidney medullary vascular network

Introduction: Regardless of initiating cause, renal injury promotes a potent pro-inflammatory environment in the outer medulla and a concomitant sustained decrease in medullary blood flow (MBF). This decline in MBF is believed to be one of the critical events in the pathogenesis of acute kidney injury (AKI), yet the precise cellular mechanism underlying this are still to be fully elucidated. MBF is regulated by contractile pericyte cells that reside on the descending vasa recta (DVR) capillaries, which are the primary source of blood flow to the medulla. Methods: Using the rat and murine live kidney slice models, we investigated the acute effects of key medullary inflammatory mediators TNF-α, IL-1β, IL-33, IL-18, C3a and C5a on vasa recta pericytes, the effect of AT1-R blocker Losartan on pro-inflammatory mediator activity at vasa recta pericytes, and the effect of 4-hour sustained exposure on immunolabelled NG2+ pericytes. Results and discussion: Exposure of rat and mouse kidney slices to TNF-α, IL-18, IL-33, and C5a demonstrated a real-time pericyte-mediated constriction of DVR. When pro-inflammatory mediators were applied in the presence of Losartan the inflammatory mediator-mediated constriction that had previously been observed was significantly attenuated. When live kidney slices were exposed to inflammatory mediators for 4-h, we noted a significant reduction in the number of NG2+ positive pericytes along vasa recta capillaries in both rat and murine kidney slices. Data collected in this study demonstrate that inflammatory mediators can dysregulate pericytes to constrict DVR diameter and reduce the density of pericytes along vasa recta vessels, further diminishing the regulatory capacity of the capillary network. We postulate that preliminary findings here suggest pericytes play a role in AKI.

Spectrum, Outcomes, and Mortality Predictors of Acute Kidney Injury among Non-COVID-19 Patients during COVID-19 Pandemic: Data from Four Intensive Care Units

Introduction

The data of acute kidney injury (AKI), that is, community-acquired AKI (CA-AKI) and hospital-acquired AKI (HA-AKI) among non-COVID patients from intensive care units (ICU) during the coronavirus disease-2019 (COVID-19) pandemic are scarce. We planned to study the change in the profile of such patients compared to the pre-pandemic era.

Materials and methods

This prospective observational study was conducted at four ICUs dealing with non-COVID patients at a government hospital in North India, and was aimed at assessing outcomes, and mortality predictors of AKI among non-COVID patients during the COVID-19 pandemic. Renal and patient survival at ICU transfer-out and hospital discharge, ICU and hospital stay duration, mortality predictors, and dialysis requirement at discharge were evaluated. The current or previous COVID-19 infection, previous AKI or chronic kidney disease (CKD), organ donors, and organ transplant patients were excluded.

Results

Among the 200 non-COVID-19 AKI patients, diabetes mellitus (DM), primary hypertension, and cardiovascular diseases were the predominant comorbidities in descending order. The commonest cause of AKI was severe sepsis, followed by systemic infections and post-surgery patients. Dialysis requirements at ICU admission during ICU stay and above 30 days were seen in 20.5, 47.5, and 6.5% of patients, respectively. Incidence of CA-AKI and HA-AKI was 1.24:1, whereas dialysis requirement above 30 days was 0.85:1, respectively. The 30-day mortality was 42%. Hepatic dysfunction [hazard ratio (HR): 3.471], septicemia (HR: 3.342), age above 60 years (HR: 4.000), higher sequential organ failure assessment (SOFA) score (HR: 1.107; p = 0.001), anemia (p = 0.003), and low serum iron (p = 0.001) were important mortality predictors in AKI.

Conclusion

Compared to the pre-COVID era, CA-AKI was more common than HA-AKI due to restricted elective surgeries during the COVID-19 pandemic. Acute kidney injury with multiorgan involvement and hepatic dysfunction, elderly age with higher SOFA score and sepsis were predictors of adverse renal and patient outcomes.

How to cite this article

Singh B, Dogra PM, Sood V, Singh V, Katyal A, Dhawan M, et al. Spectrum, Outcomes, and Mortality Predictors of Acute Kidney Injury among Non-COVID-19 Patients during COVID-19 Pandemic: Data from Four Intensive Care Units. Indian J Crit Care Med 2023;27(2):119-126.

The epidemiology and long-term outcomes of acute kidney disease in a resource-limited setting

BACKGROUND

The concept of acute kidney disease (AKD) implies kidney damage that results in a significant decrease in glomerular filtration rate, including acute kidney injury (AKI), but that is not persistent enough to meet the criteria of chronic kidney disease (CKD). While a few studies have shown associations between AKD and the risk of adverse outcomes, there is still a lack of evidence from resource-limited settings.

METHODS

All hospitalized patients at the study hospital during 2017 were retrospectively reviewed. Diagnosis of AKI, AKD, and CKD was based on the diagnostic algorithm proposed by KDIGO. Patients were followed up for 2 years to determine their risks of mortality, development of CKD, and progression of pre-existing CKD.

RESULTS

A total of 9800 patients were included in the analysis, 26.1% of whom had pre-existing CKD, while AKD without AKI was found in 8% and 7% of individuals with and without pre-existing CKD, respectively. Patients with AKD without AKI were associated with higher in-hospital mortality than those without pre-existing CKD [adjusted hazard ratio (aHR) of 2.50; 95% CI 1.43, 4.37] and with pre-existing CKD (aHR 1.79; 95% CI 1.16, 2.76). The incidence of new CKD was higher in the group of AKD without AKI than in the AKI group (34.8 vs. 14.7%).

CONCLUSION

In a resource-limited setting, AKD is associated with short- and long-term mortality and CKD progression, especially in individuals with pre-existing CKD.

Acute kidney injury following cardiopulmonary bypass in Jamaica

Objectives

The study objectives were to describe the incidence, risk factors, and outcomes of acute kidney injury after cardiopulmonary bypass in Jamaica.

Method

We performed a review of the medical records of adult patients (aged ≥ 18 years) with no prior dialysis requirement undergoing cardiopulmonary bypass at the University Hospital of the West Indies, Mona, between January 1, 2016, and June 30, 2019. Demographic, preoperative, intraoperative, and postoperative data were abstracted. Acute kidney injury was defined using Kidney Disease Improving Global Outcomes criteria. The primary outcomes were acute kidney injury incidence and all-cause 30-day mortality. Multivariable logistic regression and Cox proportional analyses were used to examine the association between the acute kidney injury risk factors and the primary outcome.

Results

Data for 210 patients (58% men, mean age 58.1 ± 12.9 years) were analyzed. Acute kidney injury occurred in 80 patients (38.1%), 44% with Kidney Disease Improving Global Outcomes I, 33% with Kidney Disease Improving Global Outcomes II, and 24% with Kidney Disease Improving Global Outcomes III. From multivariable logistic regression models, European System for Cardiac Operative Risk Evaluation II (odds ratio, 1.19; 95% confidence interval, 1.01-1.39 per unit), bypass time (odds ratio, 1.94; 95% confidence interval, 1.40-2.67 per hour), perioperative red cell transfusion (odds ratio, 3.03; 95% confidence interval, 1.36-6.76), and postoperative neutrophil lymphocyte ratio (odds ratio, 1.65; 95% confidence interval, 1.01-2.68 per 10-unit difference) were positively associated with acute kidney injury. Acute kidney injury resulted in greater median hospital stay (18 vs 11 days, P < .001) and intensive care unit stay (5 vs 3 days, P < .001), and an 8-fold increase in 30-day mortality (hazard ratio, 8.15; 95% confidence interval, 2.76-24.06, P < .001).

Conclusions

Acute kidney injury after cardiopulmonary bypass surgery occurs frequently in Jamaica and results in poor short-term outcomes. Further studies coupled with quality interventions to reduce the mortality of those with acute kidney injury are needed in the Caribbean.

Acute Kidney Failure among Brazilian Agricultural Workers: A Death-Certificate Case-Control Study

Recent evidence suggests that pesticides may play a role in chronic kidney disease. However, little is known about associations with acute kidney failure (AKF). We investigated trends in AKF and pesticide expenditures and associations with agricultural work in two Brazilian regions with intense use of pesticides, in the south and midwest. Using death certificate data, we investigated trends in AKF mortality (1980-2014). We used joinpoint regression to calculate annual percent changes in AKF mortality rates by urban/rural status and, in rural municipalities, by tertiles of per capita pesticide expenditures. We then compared AKF mortality in farmers and population controls from 2006 to 2014 using logistic regression to estimate odds ratios and 95% confidence intervals adjusted by age, sex, region, education, and race. AKF mortality increased in both regions regardless of urban/rural status; trends were steeper from the mid-1990s to 2000s, and in rural municipalities, they were higher by tertiles of pesticide expenditures. Agricultural workers were more likely to die from AKF than from other causes, especially at younger ages, among females, and in the southern municipalities. We observed increasing AKF mortality in rural areas with greater pesticide expenditures and an association of AKF mortality with agricultural work, especially among younger workers.

Pericyte-mediated constriction of renal capillaries evokes no-reflow and kidney injury following ischaemia

Acute kidney injury is common, with ~13 million cases and 1.7 million deaths/year worldwide. A major cause is renal ischaemia, typically following cardiac surgery, renal transplant or severe haemorrhage. We examined the cause of the sustained reduction in renal blood flow ('no-reflow'), which exacerbates kidney injury even after an initial cause of compromised blood supply is removed. Adult male Sprague-Dawley rats, or NG2-dsRed male mice were used in this study. After 60 min kidney ischaemia and 30-60 min reperfusion, renal blood flow remained reduced, especially in the medulla, and kidney tubule damage was detected as Kim-1 expression. Constriction of the medullary descending vasa recta and cortical peritubular capillaries occurred near pericyte somata, and led to capillary blockages, yet glomerular arterioles and perfusion were unaffected, implying that the long-lasting decrease of renal blood flow contributing to kidney damage was generated by pericytes. Blocking Rho kinase to decrease pericyte contractility from the start of reperfusion increased the post-ischaemic diameter of the descending vasa recta capillaries at pericytes, reduced the percentage of capillaries that remained blocked, increased medullary blood flow and reduced kidney injury. Thus, post-ischaemic renal no-reflow, contributing to acute kidney injury, reflects pericytes constricting the descending vasa recta and peritubular capillaries. Pericytes are therefore an important therapeutic target for treating acute kidney injury.

Conceptual model of adding antibiotics to dialysate fluid during renal replacement therapy

Studies have shown significant variability in antibiotic trough concentrations in critically ill patients receiving renal replacement therapy (RRT). The purpose of this study was to assess whether adding beta-lactam antibiotics to dialysate solution can maintain stable antibiotic concentrations during RRT in experimental conditions. A single compartment model reflecting the patient was constructed and connected to the RRT machine. Dialysate fluid was prepared in three different concentrations of meropenem (0 mg/L; 16 mg/L; 64 mg/L). For each dialysate concentration various combinations of dialysate and blood flow rates were tested by taking different samples. Meropenem concentration in all samples was calculated using spectrophotometry method. Constructed experimental model results suggest that decrease in blood meropenem concentration can be up to 35.6%. Moreover, experimental data showed that antibiotic loss during RRT can be minimized and stable plasma antibiotic concentration can be achieved with the use of a 16 mg/L Meropenem dialysate solution. Furthermore, increasing meropenem concentration up to 64 mg/L is associated with an increase antibiotic concentration up to 18.7–78.8%. Administration of antibiotics to dialysate solutions may be an effective method of ensuring a constant concentration of antibiotics in the blood of critically ill patients receiving RRT.

Incidence and Predictors of Acute Kidney Injury Among Newly Diagnosed Type 2 Diabetes Patients at Chronic Follow-Up Clinic of University of Gondar Comprehensive Specialized Hospital: A Retrospective Follow-Up Study

Background

Acute kidney injury is a common disorder worldwide, occurring in more than 13 million per year, 85% of whom live in developing countries. The high incidence of acute kidney injury among type 2 diabetic patients is a major cause of morbidity and mortality. There is limited data that address the incidence and predictors of acute kidney injury to apply evidence-based interventions in developing countries including Ethiopia specifically in the study area.

Methods

Institution-based retrospective follow-up study was conducted among 420 adults with newly diagnosed type 2 diabetes patients from January 1, 2014, to December 31, 2019. Log rank test and Kaplan–Meier curve were used to compare different categories of survival probability. In a multivariable analysis, variable having a p-value <0.05 in the Cox, proportional hazard model was considered as independent predictors.

Results

Overall, 19.76% (95% CI; 16.2–23.8) of the study population developed acute kidney injury, with a median follow-up period of 30.75 months. Congestive heart failure [adjusted hazard ratio (AHR): 2.89 (95% CI; 1.62, 5.13)], chronic kidney disease [AHR: 2.92 (95% CI; 1.56, 5.48)], hypertension [AHR: 2.87 (95% CI; 1.20, 6.90)], and diabetic nephropathy [AHR: 2.04 (95% CI; 1.13, 3.68)] were found to be predictors of acute kidney injury.

Conclusion

The incidence of acute kidney injury among type 2 diabetes patients was high in the study area. In patients with hypertension congestive heart failure, chronic kidney disease, and diabetic nephropathy efforts should be made to diagnose AKI early and treat it – in addition to better control accordingly among type 2 diabetes mellitus patients.

Clinical Profile and Short-Term Outcomes of Acute Kidney Injury in Patients Admitted to a Teaching Hospital in Ethiopia: A Prospective Study

Background

Acute kidney injury (AKI) is a common complication in hospitalized patients and a marker for poor patient outcomes. It is associated with a high risk of mortality and other short- and long-term adverse outcomes. We aim to assess the clinical profile and short-term outcomes of acute kidney injury in adult patients admitted to the medical ward.

Methods

A hospital-based prospective observational study was conducted from October 2019 to January 2020. All adult patients diagnosed as AKI using kidney disease improving global outcomes (KIDGO) criteria were included in the study and prospectively followed to document the short-term outcomes. Outcomes and their predictors were determined using multivariate logistic regression. P-value less than 0.05 was taken as statistically significant.

Results

A total of 160 patients were included in the study. Out of this, 96 (60%) were males, 118 (74%) had community-acquired AKI, and 51 (32%) had stage 3 AKI. Common causes of AKI were hypovolemia 62 (39%) and sepsis 35 (22%). Hypertension 69 (43%) and heart failure 50 (31%) were common underlying comorbidities. Fifty-six (35%) patients developed systemic complications, 98 (61.2%) had persistent AKI, 136 (85%) had prolonged length of hospital stay, and 18 (11%) were readmitted to the hospital. The presence of AKI-related complication (AOR=2.7, 95% CI: 1.14–6.58, p=0.024), and duration of AKI (AOR=9.7, 95% CI: 2.56–36.98, p=0.001) were factors associated with prolonged length of hospital stay. Preexisting CKD (AOR=3.6, 95% CI: 1.02–13.14, p=0.035) and stage 3 AKI (AOR=2.1, 95% CI: 1.6–3.57, p=0.04) were factors associated with 30-day hospital readmission.

Conclusion

Hypovolemia and infections were the primary causes of AKI. Complications, prolonged length of hospital stay, persistent AKI, and rehospitalization were poor short-term outcomes of AKI. Early diagnosis and timely management of AKI particularly in high-risk hospitalized patients, and post-AKI care including management of comorbidities for AKI survivors should improve these poor short-term outcomes.

RETRACTED: Depleting microRNA-183-3p improves renal tubulointerstitial fibrosis after acute kidney injury via SIRT1/PUMA/FOXO3a deacetylation

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figs. 2E, and 3C, which appear to have the same eyebrow shaped phenotype as many other publications tabulated here (https://docs.google.com/spreadsheets/d/149EjFXVxpwkBXYJOnOHb6RhAqT4a2llhj9LM60MBffM/edit#gid=0). The journal requested the corresponding author comment on these concerns and provide the raw data. However the authors were not able to satisfactorily fulfil this request and therefore the Editor-in-Chief decided to retract the article.

Pragmatic Recommendations for the Prevention and Treatment of Acute Kidney Injury in Patients with COVID-19 in Low- and Middle-Income Countries

Current recommendations for the management of patients with COVID-19 and acute kidney injury (AKI) are largely based on evidence from resource-rich settings, mostly located in high-income countries. It is often unpractical to apply these recommendations to resource-restricted settings. We report on a set of pragmatic recommendations for the prevention, diagnosis, and management of patients with COVID-19 and AKI in low- and middle-income countries (LMICs). For the prevention of AKI among patients with COVID-19 in LMICs, we recommend using isotonic crystalloid solutions for expansion of intravascular volume, avoiding nephrotoxic medications, and using a conservative fluid management strategy in patients with respiratory failure. For the diagnosis of AKI, we suggest that any patient with COVID-19 presenting with an elevated serum creatinine level without available historical values be considered as having AKI. If serum creatinine testing is not available, we suggest that patients with proteinuria should be considered to have possible AKI. We suggest expansion of the use of point-of-care serum creatinine and salivary urea nitrogen testing in community health settings, as funding and availability allow. For the management of patients with AKI and COVID-19 in LMICS, we recommend judicious use of intravenous fluid resuscitation. For patients requiring dialysis who do not have acute respiratory distress syndrome (ARDS), we suggest using peritoneal dialysis (PD) as first choice, where available and feasible. For patients requiring dialysis who do have ARDS, we suggest using hemodialysis, where available and feasible, to optimize fluid removal. We suggest using locally produced PD solutions when commercially produced solutions are unavailable or unaffordable.

Recognition and management of community-acquired acute kidney injury in low-resource settings in the ISN 0by25 trial: A multi-country feasibility study

BACKGROUND

Acute kidney injury (AKI) is increasingly encountered in community settings and contributes to morbidity, mortality, and increased resource utilization worldwide. In low-resource settings, lack of awareness of and limited access to diagnostic and therapeutic interventions likely influence patient management. We evaluated the feasibility of the use of point-of-care (POC) serum creatinine and urine dipstick testing with an education and training program to optimize the identification and management of AKI in the community in 3 low-resource countries.

METHODS AND FINDINGS

Patients presenting to healthcare centers (HCCs) from 1 October 2016 to 29 September 2017 in the cities Cochabamba, Bolivia; Dharan, Nepal; and Blantyre, Malawi, were assessed utilizing a symptom-based risk score to identify patients at moderate to high AKI risk. POC testing for serum creatinine and urine dipstick at enrollment were utilized to classify these patients as having chronic kidney disease (CKD), acute kidney disease (AKD), or no kidney disease (NKD). Patients were followed for a maximum of 6 months with repeat POC testing. AKI development was assessed at 7 days, kidney recovery at 1 month, and progression to CKD and mortality at 3 and 6 months. Following an observation phase to establish baseline data, care providers and physicians in the HCCs were trained with a standardized protocol utilizing POC tests to evaluate and manage patients, guided by physicians in referral hospitals connected via mobile digital technology. We evaluated 3,577 patients, and 2,101 were enrolled: 978 in the observation phase and 1,123 in the intervention phase. Due to the high number of patients attending the centers daily, it was not feasible to screen all patients to assess the actual incidence of AKI. Of enrolled patients, 1,825/2,101 (87%) were adults, 1,117/2,101 (53%) were females, 399/2,101 (19%) were from Bolivia, 813/2,101 (39%) were from Malawi, and 889/2,101 (42%) were from Nepal. The age of enrolled patients ranged from 1 month to 96 years, with a mean of 43 years (SD 21) and a median of 43 years (IQR 27-62). Hypertension was the most common comorbidity (418/2,101; 20%). At enrollment, 197/2,101 (9.4%) had CKD, and 1,199/2,101 (57%) had AKD. AKI developed in 30% within 7 days. By 1 month, 268/978 (27%) patients in the observation phase and 203/1,123 (18%) in the intervention phase were lost to follow-up. In the intervention phase, more patients received fluids (observation 714/978 [73%] versus intervention 874/1,123 [78%]; 95% CI 0.63, 0.94; p = 0.012), hospitalization was reduced (observation 578/978 [59%] versus intervention 548/1,123 [49%]; 95% CI 0.55, 0.79; p < 0.001), and admitted patients with severe AKI did not show a significantly lower mortality during follow-up (observation 27/135 [20%] versus intervention 21/178 [11.8%]; 95% CI 0.98, 3.52; p = 0.057). Of 504 patients with kidney function assessed during the 6-month follow-up, de novo CKD arose in 79/484 (16.3%), with no difference between the observation and intervention phase (95% CI 0.91, 2.47; p = 0.101). Overall mortality was 273/2,101 (13%) and was highest in those who had CKD (24/106; 23%), followed by those with AKD (128/760; 17%), AKI (85/628; 14%), and NKD (36/607; 6%). The main limitation of our study was the inability to determine the actual incidence of kidney dysfunction in the health centers as it was not feasible to screen all the patients due to the high numbers seen daily.

CONCLUSIONS

This multicenter, non-randomized feasibility study in low-resource settings demonstrates that it is feasible to implement a comprehensive program utilizing POC testing and protocol-based management to improve the recognition and management of AKI and AKD in high-risk patients in primary care.

Acute kidney injury and mortality in pediatric Lassa fever versus question of access to dialysis

OBJECTIVES

To assess the prevalence of acute kidney injury (AKI), and its impact on outcome in hospitalized pediatric patients with Lassa fever (LF).

METHODS

We reviewed the presenting clinical and laboratory features and outcomes of 40 successive hospitalized children with PCR-confirmed LF. The diagnosis and staging of AKI was based on KDIGO criteria. We compared groups of patients using t- or χ2 tests as necessary, and took p-values <0.05 as indicative of the presence of significant differences.

RESULTS

Sixteen (40%) children had AKI. Case fatality rate (CFR) was 9/16 (56%) in children with and 1/24 (4%) in those without AKI (OR [95% CI] of CFR associated with AKI = 29.57 [3.17, 275.7]). Presentation with abnormal bleeding (p = 0.008), encephalopathy (p = 0.004), hematuria plus proteinuria (p = 0.013), and elevated serum transaminase levels (p <0.02) were significantly associated with an increased prevalence of AKI.

CONCLUSION

AKI prevalence in hospitalized pediatric patients with Lassa fever is high, and correlated with illness severity/CFR. The high prevalence underscores the need for access to hemodialysis, and clinical presentation and/or presence of hematuria plus proteinuria could serve as a ready prompt for referral for such specialized care.

The Charlson Comorbidity Index: can it predict the outcome in acute kidney injury?

PURPOSE

Comorbidity has a significant impact on the health status and treatment outcome of a patient. The Charlson comorbidity index (CCI) is a frequently used scoring system, which evaluates the prognosis based on the patient's comorbid conditions. The aim of this study was to evaluate the usefulness of CCI in predicting the mortality and renal recovery in non-critically ill patients with severe AKI.

METHODS

A total of 530 adult patients who were referred from the emergency department and underwent intermittent urgent hemodialysis (uHD) were enrolled in the study. Personal history for comorbidities were recorded and then assessed using the CCI.

RESULTS

The mean CCI score was 3.3 ± 2.6. In our multivariate analysis, higher white blood cell count was associated with mortality (p = 0.023). The other parameters including CCI score were not found to be significantly associated with mortality excluding patients with sepsis. Moreover, the CCI was not significantly useful in the discrimination of patients with complete recovery from patients who remained dependent to dialysis.

CONCLUSIONS

We could not find significant association between CCI and short-term hospital mortality and renal outcome. Whereas, malnutrition, inflammation and general aging may have impact on short-term mortality among patients.

Changing epidemiology and outcomes of acute kidney injury in Brazilian patients: a retrospective study from a teaching hospital

PURPOSE

While considerable information is available on acute kidney injury (AKI) in North America and Europe, large comprehensive epidemiologic studies on AKI from Latin America and Asia are still lacking. The present study aimed to evaluate the epidemiology and outcomes of AKI in patients evaluated by nephrologists in a Brazilian teaching hospital.

METHODS

We performed a large retrospective observational study that looked into the epidemiology of AKI and its effect on patient outcomes across time periods. For comparison purposes, patients were divided into two groups according to the year of follow up: 2011-2014 and 2015-2018.

RESULTS

We enrolled 7976 AKI patients and, after excluding patients with chronic kidney disease stages 4 and 5, kidney transplant recipients and those with incomplete data, 5428 AKI patients were included (68%). The maximum AKI stage was 3 (50.6%), and there was a mortality rate of 34.3% (1865 patients). Dialysis treatment was indicated in 928 patients (17.1%). Patient survival improved along the study periods, and patients treated in 2015-2018 had a relative risk death reduction of 0.89 (95% CI 0.81-0.98, p = 0.02). The independent risk factors for mortality were sepsis, > 65 years of age, admission to the intensive care unit, AKI-KDIGO 3, recurrent AKI, no metabolic and fluid demand to capacity imbalance (as a dialysis indication), and the period of treatment.

CONCLUSION

We observed an improvement in AKI patient survival over the years, even after correction for several confounders and using a competing risk approach. Identification of risk factors for mortality can help in decision-making for timely intervention, leading to better clinical outcomes.

Outcomes in acute kidney injury in noncritically ill patients lately referred to nephrologist in a developing country: a comparison of AKIN and KDIGO criteria

Background

In low-middle-income countries (LMICs), data regarding acute kidney injury (AKI) are scarce. AKI patients experience delayed diagnosis. This study aimed to evaluate whether delayed nephrologist consultation (NC) affected outcomes of AKI patients and compare Acute Kidney Injury Network (AKIN) and Kidney Disease: Improving Global Outcomes (KDIGO).

Methods

An observational, retrospective study was conducted in a tertiary public hospital in an LMIC.

Results

Overall, 103 AKI patients were analysed. In-hospital mortality was 61.16%, and dialysis was required in 38.83%. NC took place after 48 h in 68.93% of the patients. Mean time for NC was 5.22 ± 4.30 days. At NC, serum creatinine was 4.48 (±3.40) mg/dL and blood urea nitrogen was 68.21 (± 35.02) mg/dL. The AKIN and KDIGO stage stratifications were identical; KDIGO stage 3 was seen in 58.25% of the patients. The group with NC >  4 days had a mortality rate of 74.46% and the group with NC ≤ 4 days had a mortality rate of 50% (p = 0.011). Multivariate analysis showed that haemodialysis was independently associated with mortality. NC >  4 days was associated with death [odds ratio 2.66 (95% confidence interval, 1.36–4.35), p = 0.001]. Logistic regression showed an OR of 1.20 (95% CI, 1.05–1.37) (p = 0.008) for each day of delayed NC.

Conclusion

Delayed NC was associated with mortality even after adjustments, as was haemodialysis, though marginally. In AKI patients with NC > 4 days, there was a high prevalence of KDIGO stage 3, and AKIN and KDIGO criteria were identical.

Recent Pattern of Acute Kidney Injury in Bosnia and Herzegovina

Introduction:

Acute kidney injury (AKI) is one of the major public health issues with constantly increasing incidence, with epidemiology and outcomes that vary substantially across the world.

Aim:

Aim of our study was to determine epidemiological characteristics and causes of AKI and to provide a comparison of our findings with data from other low and middle income countries.

Methods:

This retrospective observational study conducted during an 18-month period included 84 patients. Data were collected from hospital information system and patients’ medical records. All data were analyzed using descriptive statistics.

Results:

More than two-thirds of patients were older than 56 years. Most cases of AKI (54,76%) were hospital-acquired and predominantly developed in intensive care units (32,14%). Dominant risk factor was underlying chronic kidney disease (48,81%) and chronic heart failure (45,24. In majority of patients (73,81%) were identified multiple factors that may have contributed to AKI: infection (90,48%), prerenal factors (77,38%), nephrotoxic agents (69,05%), and sepsis (28,57%). Multiple organ failure was identified in 94,05% of patients: cardiovascular (64,56%), respiratory (58,23%) and hematological (56,96%) system. Half of all patients were alive at last observation day. Leading cause of death was infection/sepsis (21,43%), followed by cancer (16,67%) and shock (14,28%).

Conclusion:

Data on AKI show great variation, but general picture of AKI resembles more that from high income countries. The need for dialysis and overall mortality remains high. This highlights the importance of early recognition of AKI, timely referral to nephrologist and need for national guidelines and standardized protocols for AKI.

Acute Kidney Injury in Patients Undergoing Cardiac Transplantation: A Meta-Analysis

Background: Acute kidney injury (AKI) is a common complication following solid-organ transplantation. However, the epidemiology of AKI and mortality risk of AKI among patients undergoing cardiac transplantation is not uniformly described. We conducted this study to assess the incidence of AKI and mortality risk of AKI in adult patients after cardiac transplantation. Methods: A systematic review of EMBASE, MEDLINE, and Cochrane Databases was performed until June 2019 to identify studies evaluating the incidence of AKI (by standard AKI definitions), AKI requiring renal replacement therapy (RRT), and mortality risk of AKI in patients undergoing cardiac transplantation. Pooled AKI incidence and mortality risk from the included studies were consolidated by random-effects model. The protocol for this study is registered with PROSPERO (no. CRD42019134577). Results: 27 cohort studies with 137,201 patients undergoing cardiac transplantation were identified. Pooled estimated incidence of AKI and AKI requiring RRT was 47.1% (95% CI: 37.6-56.7%) and 11.8% (95% CI: 7.2-18.8%), respectively. The pooled ORs of hospital mortality and/or 90-day mortality among patients undergoing cardiac transplantation with AKI and AKI requiring RRT were 3.46 (95% CI, 2.40-4.97) and 13.05 (95% CI, 6.89-24.70), respectively. The pooled ORs of 1-year mortality among patients with AKI and AKI requiring RRT were 2.26 (95% CI, 1.56-3.26) and 3.89 (95% CI, 2.49-6.08), respectively. Conclusion: Among patients undergoing cardiac transplantation, the incidence of AKI and severe AKI requiring RRT are 47.1% and 11.8%, respectively. AKI post cardiac transplantation is associated with reduced short term and 1-year patient survival.

Incidence and Impact of Acute Kidney Injury after Liver Transplantation: A Meta-Analysis

BACKGROUND

The study's aim was to summarize the incidence and impacts of post-liver transplant (LTx) acute kidney injury (AKI) on outcomes after LTx.

METHODS

A literature search was performed using the MEDLINE, EMBASE and Cochrane Databases from inception until December 2018 to identify studies assessing the incidence of AKI (using a standard AKI definition) in adult patients undergoing LTx. Effect estimates from the individual studies were derived and consolidated utilizing random-effect, the generic inverse variance approach of DerSimonian and Laird. The protocol for this systematic review is registered with PROSPERO (no. CRD42018100664).

RESULTS

Thirty-eight cohort studies, with a total of 13,422 LTx patients, were enrolled. Overall, the pooled estimated incidence rates of post-LTx AKI and severe AKI requiring renal replacement therapy (RRT) were 40.7% (95% CI: 35.4%⁻46.2%) and 7.7% (95% CI: 5.1%⁻11.4%), respectively. Meta-regression showed that the year of study did not significantly affect the incidence of post-LTx AKI (p = 0.81). The pooled estimated in-hospital or 30-day mortality, and 1-year mortality rates of patients with post-LTx AKI were 16.5% (95% CI: 10.8%⁻24.3%) and 31.1% (95% CI: 22.4%⁻41.5%), respectively. Post-LTx AKI and severe AKI requiring RRT were associated with significantly higher mortality with pooled ORs of 2.96 (95% CI: 2.32⁻3.77) and 8.15 (95%CI: 4.52⁻14.69), respectively. Compared to those without post-LTx AKI, recipients with post-LTx AKI had significantly increased risk of liver graft failure and chronic kidney disease with pooled ORs of 3.76 (95% CI: 1.56⁻9.03) and 2.35 (95% CI: 1.53⁻3.61), respectively.

CONCLUSION

The overall estimated incidence rates of post-LTx AKI and severe AKI requiring RRT are 40.8% and 7.0%, respectively. There are significant associations of post-LTx AKI with increased mortality and graft failure after transplantation. Furthermore, the incidence of post-LTx AKI has remained stable over the ten years of the study.

Acute kidney injury after lung cancer surgery: Incidence and clinical relevance, predictors, and role of N-terminal pro B-type natriuretic peptide

BACKGROUND

Acute kidney injury (AKI) frequently occurs in several medical and surgical settings, and it is associated with increased morbidity and mortality. In patients undergoing lung cancer surgery, AKI has not been fully investigated. We prospectively evaluated the incidence, clinical relevance, and risk factors of AKI in patients undergoing lung cancer surgery. Moreover, we estimated the accuracy of N-terminal pro-B-type natriuretic peptide (NT-proBNP) in the prediction of AKI.

METHODS

Patients undergoing lung cancer surgery were included in the study. Plasma NT-proBNP was measured before and soon after surgery. Postoperative AKI was defined according to the Acute Kidney Injury Network (AKIN) classification.

RESULTS

A total of 2179 patients were enrolled. Of them, 222 (10%) developed AKI and had a more complicated in-hospital clinical course (overall complication rate: 35% vs. 16%; P < 0.0001), and a longer hospital stay (10 ± 7 vs. 7 ± 4 days; P < 0.0001). The incidence of AKI increased in parallel with the extent of lung resection. Among the independent predictors of AKI, serum creatinine (area under the curve [AUC] 0.70 [95% CI 0.67-0.74]) and NT-proBNP (AUC 0.71 [95% CI 0.67-0.74]) provided the highest predictive accuracy, and their combination further significantly improved AKI prediction (AUC 0.74 [95% CI 0.71-0.77]). No difference in AKI prediction was observed between preoperative and postoperative NT-proBNP (P = 0.84).

CONCLUSIONS

Acute kidney injury occurs in 10% of patients undergoing lung cancer surgery, and it is associated with a high incidence of postoperative complications. The risk of AKI can be accurately predicted by the combined evaluation of preoperative serum creatinine and NT-proBNP.

Peritoneal Dialysis in Austere Environments: An Emergent Approach to Renal Failure Management

Peritoneal dialysis (PD) is a means of renal replacement therapy (RRT) that can be performed in remote settings with limited resources, including regions that lack electrical power. PD is a mainstay of end-stage renal disease (ESRD) therapy worldwide, and the ease of initiation and maintenance has enabled it to flourish in both resource-limited and resource-abundant settings. In natural disaster scenarios, military conflicts, and other austere areas, PD may be the only available life-saving measure for acute kidney injury (AKI) or ESRD. PD in austere environments is not without challenges, including catheter placement, availability of dialysate, and medical complications related to the procedure itself. However, when hemodialysis is unavailable, PD can be performed using generally available medical supplies including sterile tubing and intravenous fluids. Amidst the ever-increasing global burden of ESRD and AKI, the ability to perform PD is essential for many medical facilities.

Guidelines, policies, and barriers to kidney care: findings from a global survey

An international survey led by the International Society of Nephrology in 2016 assessed the current capacity of kidney care worldwide. To better understand how governance and leadership guide kidney care, items pertinent to government priority, advocacy, and guidelines, among others, were examined. Of the 116 responding countries, 36% (n = 42) reported CKD as a government health care priority, which was associated with having an advocacy group (χ2 = 11.57; P = 0.001). Nearly one-half (42%; 49 of 116) of countries reported an advocacy group for CKD, compared with only 19% (21 of 112) for AKI. Over one-half (59%; 68 of 116) of countries had a noncommunicable disease strategy. Similarly, 44% (48 of 109), 55% (57 of 104), and 47% (47 of 101) of countries had a strategy for nondialysis CKD, chronic dialysis, and kidney transplantation, respectively. Nearly one-half (49%; 57 of 116) reported a strategy for AKI. Most countries (79%; 92 of 116) had access to CKD guidelines and just over one-half (53%; 61 of 116) reported guidelines for AKI. Awareness and adoption of guidelines were low among nonnephrologist physicians. Identified barriers to kidney care were factors related to patients, such as knowledge and attitude (91%; 100 of 110), physicians (84%; 92 of 110), and geography (74%; 81 of 110). Specific to renal replacement therapy, patients and geography were similarly identified as a barrier in 78% (90 of 116) and 71% (82 of 116) of countries, respectively, with the addition of nephrologists (72%; 83 of 116) and the health care system (73%; 85 of 116). These findings inform how kidney care is currently governed globally. Ensuring that guidelines are feasible and distributed appropriately is important to enhancing their adoption, particularly in primary care. Furthermore, increasing advocacy and government priority, especially for AKI, may increase awareness and strategies to better guide kidney care.

Epidemiology and Outcomes of Acute Kidney Injury in Critically Ill: Experience from a Tertiary Care Center

There is only limited information on the epidemiology and outcomes of acute kidney injury (AKI) in critically ill patients from low- and middle-income countries. This study aims to identify the etiology, short-term outcomes, and determinants of mortality in patients with AKI admitted to multiple medical and surgical Intensive Care Units (ICU's) in a tertiary care center. The study also aims to compare the clinical characteristics and outcomes of community-acquired AKI (CAAKI) and hospital-acquired AKI (HAAKI). A prospective, observational study was done from June 2013 to October 2015. All patients over 18 years with AKI admitted in various medical and surgical ICU's seeking nephrology referral were included. AKI was defined according to KDIGO criteria. The follow-up period was 30 days. A total of 236 patients were recruited from five medical and nine surgical ICU's. Majority (73.3%) were males. About 53.38% patients had CAAKI, whereas 46.61% had HAAKI. The predominant etiologies for AKI were sepsis (22.4%), trauma due to road traffic accidents (21.18%), acute abdomen (perforation, acute pancreatitis, bowel gangrene, intestinal obstruction and cholangitis) (18.64%), and cardiac diseases (10.59%). Sepsis and acute abdomen were the most common causes of CAAKI, whereas trauma and cardiac causes were the predominant causes of HAAKI (P < 0.05). Patients with HAAKI were younger, admitted in surgical units, had lower SOFA scores, lower serum creatinine, lesser need for dialysis, longer hospital stay, and earlier stages of AKI compared to patients with CAAKI (P < 0.05). The 30-day mortality was 52.54%. The mortality was not different between CAAKI and HAAKI (56.3% vs. 48.18%; relative risk = 0.86: 95% confidence interval 0.67–1.1). The mortality was similar across different stages of AKI.

Risk, Predictors, and Outcomes of Acute Kidney Injury in Patients Admitted to Intensive Care Units in Egypt

Epidemiology of acute kidney injury (AKI) in developing countries is under-studied. We evaluated the risk and prognosis of AKI in patients admitted to intensive care units (ICUs) in Egypt. We recruited consecutive adults admitted to ICUs in Alexandria Teaching Hospitals over six months. We used the KDIGO criteria for AKI. We followed participants until the earliest of ICU discharge, death, day 30 from entry or study end. Of the 532 participants (median age 45 (Interquartile range [IQR]: 30-62) years, 41.7% male, 23.7% diabetics), 39.6% had AKI at ICU admission and 37.4% developed AKI after 24 hours of ICU admission. Previous need of diuretics, sepsis and low education were associated with AKI at ICU admission; APACHE II score independently predicted AKI after ICU admission. A total of 120 (22.6%) patients died during 30-day follow-up. Compared to patients who remained AKI-free, mortality was significantly higher in patients who had AKI at study entry (Hazard Ratio [HR] 2.14; 95% Confidence Interval [CI] 1.02-4.48) or developed AKI in ICU (HR 2.74; 95% CI 1.45-5.17). The risk of AKI is high in critically ill people and predicts poor outcomes. Further studies are needed to estimate the burden of AKI among patients before ICU admission.

Definition, Management, and Outcomes of Acute Kidney Injury: An International Survey of Nephrologists

Background

Acute kidney injury (AKI) is a complex disease burdened by uncertainties of definition, management strategies, and prognosis. This study explores the relationship between demographic characteristics of nephrologists and their perceptions about the definition, management, and follow-up of AKI.

Methods

We developed a Web-based survey, the International Survey on Acute Kidney Injury (ISAKI), consisting of 29 items in 4 categories: (1) demographic and practice characteristics, (2) definition of AKI, (3) management of renal replacement therapy (RRT) in AKI, and (4) sequelae of AKI. A multivariable stepwise logistic regression model was used to examine relationships between the dependent variables and the demographic characteristics of the respondents.

Results

Responses from 743 nephrologists from 90 countries were analyzed. The majority (60%) of respondents reported using RIFLE and/or AKIN criteria regularly to define AKI, although US nephrologists were less likely to do so (OR: 0.58; 95% CI: 0.42-0.85). The most common initial RRT modality was intermittent hemodialysis (63.5%), followed by continuous RRT (23.8%). Faculty affiliation was associated with a higher likelihood of using a dialysis schedule of ≥4 times a week (OR: 1.75; 95% CI: 1.20-2.55). The respondents believed that a single episode of AKI increases the likelihood of development of chronic kidney disease (CKD) (55%), subsequent AKI (36%), and rapid progression of preexisting CKD (87%). US nephrologists were less likely to recommend follow-up after resolution of AKI (OR: 0.15; 95% CI: 0.07-0.33).

Conclusions

Our findings highlight the need for a widely accepted consensus definition of AKI, a uniform approach to management, and improved follow-up after resolution of AKI episodes.

Causal relationship between hypoalbuminemia and acute kidney injury

Our meta-analysis published in 2010 provided evidence that low levels of serum albumin (hypoalbuminemia) are a significant independent predictor of acute kidney injury (AKI) and death following AKI. Since then, a large volume of additional data from observational clinical studies has been published further evaluating the relationship between serum albumin and AKI occurrence. This is an updated review of the literature to re-evaluate the hypothesis that hypoalbuminemia is independently associated with increased AKI risk. Eligible studies published from September 2009 to December 2016 were sought in PubMed (MEDLINE) and forty-three were retained, the great majority being retrospective observational cohort studies. These included a total of about 68000 subjects across a diverse range of settings, predominantly cardiac surgery and acute coronary interventions, infectious diseases, transplant surgery, and cancer. Appraisal of this latest data set served to conclusively corroborate and confirm our earlier hypothesis that lower serum albumin is an independent predictor both of AKI and death after AKI, across a range of clinical scenarios. The body of evidence indicates that hypoalbuminemia may causally contribute to development of AKI. Furthermore, administration of human albumin solution has the potential to prevent AKI; a randomized, controlled study provides evidence that correcting hypoalbuminemia may be renal-protective. Therefore, measurement of serum albumin to diagnose hypoalbuminemia may help identify high-risk patients who may benefit from treatment with exogenous human albumin. Multi-center, prospective, randomized, interventional studies are warranted, along with basic research to define the mechanisms through which albumin affords nephroprotection.

Acute Kidney Injury Risk Assessment: Differences and Similarities Between Resource-Limited and Resource-Rich Countries

The incidence of acute kidney injury (AKI) among acutely ill patients is reportedly very high and has vexing consequences on patient outcomes and health care systems. The risks and impact of AKI differ between developed and developing countries. Among developing countries, AKI occurs in young individuals with no or limited comorbidities, and is usually due to environmental causes, including infectious diseases. Although several risk factors have been identified for AKI in different settings, there is limited information on how risk assessment can be used at population and patient levels to improve care in patients with AKI, particularly in developing countries where significant health disparities may exist. The Acute Disease Quality Initiative consensus conference work group addressed the issue of identifying risk factors for AKI and provided recommendations for developing individualized risk stratification strategies to improve care. We proposed a 5-dimension, evidence-based categorization of AKI risk that allows clinicians and investigators to study, define, and implement individualized risk assessment tools for the region or country where they practice. These dimensions include environmental, socioeconomic and cultural factors, processes of care, exposures, and the inherent risks of AKI. We provide examples of these risks and describe approaches for risk assessments in the developing world. We anticipate that these recommendations will be useful for health care providers to plan and execute interventions to limit the impact of AKI on society and each individual patient. Using a modified Delphi process, this group reached consensus regarding several aspects of AKI risk stratification.

Estradiol mitigates ischemia reperfusion-induced acute renal failure through NMDA receptor antagonism in rats

In the present study, we investigated possible involvement of N-methyl-D-aspartate receptors (NMDAR) in estradiol mediated protection against ischemia reperfusion (I/R)-induced acute renal failure (ARF) in rats. Bilateral renal ischemia of 40 min followed by reperfusion for 24 h induced ARF in male wistar rats. Quantification of serum creatinine, creatinine clearance (CrCl), blood urea nitrogen (BUN), uric acid, potassium, fractional excretion of sodium (Fe_Na), and urinary microproteins was done to assess I/R-induced renal damage in rats. Oxidative stress in kidneys was measured in terms of myeloperoxidase activity, thiobarbituric acid reactive substances, superoxide anion generation, and reduced glutathione levels. Hematoxylin & eosin and periodic acid Schiff stains were used to reveal structural changes in renal tissues. Estradiol benzoate (0.5 and 1.0 mg/kg, intraperitoneally, i.p.) was administered 1 h prior to I/R in rats. In separate groups, rats were treated with NMDAR agonists, glutamic acid (200 mg/kg, i.p.), and spermidine (20 mg/kg, i.p.) before administration of estradiol. Marked increase in serum creatinine, BUN, uric acid, serum potassium, Fe_Na, microproteinuria, and reduction in CrCl demonstrated I/R-induced ARF in rats. Treatment with estradiol mitigated I/R-induced changes in serum/urine parameters. Moreover, estrogen attenuated oxidative stress and structural changes in renal tissues. Prior administration of glutamic acid and spermidine abolished estradiol mediated renoprotection in rats. These results indicate the involvement of NMDAR in estradiol mediated renoprotective effect. In conclusion, we suggest that NMDAR antagonism serves as one of the mechanisms in estradiol-mediated protection against I/R-induced ARF in rats.

International Society of Nephrology's 0by25 initiative (zero preventable deaths from acute kidney injury by 2025): focus on diagnosis of acute kidney injury in low-income countries

In developing countries with limited medical infrastructure, preservation and recovery of renal function following acute kidney injury (AKI) is difficult. In conjunction with clinical presentation, rapid measurement of renal function is essential for early diagnosis and management. Especially in low- and middle-income countries, simple interventions such as hydration and avoidance of toxins have the highest probability of recovery. In such contexts, measurement of urine volume and osmolality and serum creatinine with point-of-care devices and saliva urea nitrogen dipsticks can be valuable. This review aims to identify currently available methodologies to assist in reaching the ambitious goal of the 0by25 initiative to eliminate all preventable deaths from AKI by 2025.