Acute Kidney Injury in Latin America

Acute kidney injury (AKI) is a major global health issue with significant morbidity and mortality, particularly in low- and middle-income regions like Latin America. AKI prevalence varies across Latin America, with higher rates in rural and underserved areas. Key risk factors include socioeconomic disparities, comorbid conditions such as diabetes and hypertension, and environmental hazards. Infections, especially tropical diseases, and exposure to nephrotoxins, including herbal remedies, are common causes of AKI. Management of AKI faces significant hurdles because of limited access to diagnostic tools, variability in clinical practices, and a shortage of trained health care professionals. The availability of dialysis and renal replacement therapies is often constrained by economic and infrastructural limitations. Public health initiatives focusing on prevention, screening, and early detection are critical to mitigate the impact of AKI. Research in AKI across Latin America is hampered by data gaps and limited funding. Multicenter collaborations and the development of region-specific guidelines are essential to improving outcomes. Addressing these challenges will help reduce the burden of AKI and improve health care systems across the region. This review examines the unique epidemiology, risk factors, and health care challenges surrounding AKI in the region.

Urinary and Plasma miRNAs in the Early Detection of Acute Kidney Injury and Their Possible Role as Therapeutic Targets

Acute Kidney Injury (AKI) is a severe clinical condition featured by a rapid decrease in kidney function in a short period of time. AKI, which is often secondary to sepsis, ischemia-reperfusion and drug toxicity, is associated to high morbidity and mortality. Moreover, it contributes to the development of chronic kidney disease (CKD), due to maladaptive or incomplete repair mechanisms, resulting in renal fibrosis. Small non-coding RNA has recently emerged as a novel biomarker for the early detection and treatment of AKI. In particular, microRNAs (miRNAs) are non-coding RNA molecules of 21-25 nucleotides regulating the expression of protein-coding genes through sequence-specific recognition. Due to their high stability in biological fluids, such as urine and plasma, they can be reliably analyzed and quantified, and for this reason they can be considered potential diagnostic and therapeutic biomarkers. Specifically, miRNAs have been demonstrated to predict AKI before the increase in creatinine levels, thus improving the management of this syndrome. In this review, we provide a comprehensive overview of the role of urinary and plasma miRNAs in the early detection and treatment of AKI.

Continuous Renal Replacement Therapy Versus Intermittent Hemodialysis for Renal Prognosis in Elderly Patients With Acute Kidney Injury

Background: Continuous renal replacement therapy (CRRT) and intermittent hemodialysis (IHD) represent two common modes of renal replacement therapy (RRT) for elderly patients with acute kidney injury (AKI), but their clinical effectiveness is debated. This study aimed to compare the impact of CRRT and IHD on renal prognosis in elderly patients with AKI by analyzing their clinical data. Methods: The retrospective study population included elderly patients admitted to Xiangya Hospital between 2018 and 2022, who required RRT for AKI. Patients were separated into two cohorts based on the original RRT modes (CRRT or IHD). In our study, the primary outcome was recovery of renal function at discharge and the secondary outcome was RRT dependency rate at 90 days. A multivariate logistic regression model was constructed for the purpose of comparing the impact of CRRT and IHD on renal prognosis. Results: The mortality rate at the time of patient discharge was significantly elevated in the CRRT cohort relative to the IHD cohort (49.6% vs. 2.1%, p < 0.001). However, for the 155 patients who survived at discharge, the analysis revealed no statistically significant discrepancy in renal recovery across the two groups (40.3% vs. 59.7%, p = 0.694). Multivariate logistic regression analysis showed no statistically meaningful distinction among the CRRT and IHD groups concerning renal function recovery at discharge. Nevertheless, in comparison with IHD, CRRT reduced the risk of RRT dependence at 90 days. Conclusions: Our study indicated that CRRT and IHD have comparable effects on renal recovery at discharge in elderly patients with AKI who require RRT. However, in comparison with IHD, CRRT was linked to a diminished likelihood of requiring RRT at 90 days.

Involvement of Mineralocorticoid Receptor Activation by High Mobility Group Box 1 and Receptor for Advanced Glycation End Products in the Development of Acute Kidney Injury

Key Points

Our study revealed that high mobility group box 1 activates the mineralocorticoid receptor (MR) through the receptor for advanced glycation end products (RAGE) in AKI. MR antagonists and RAGE aptamers inhibited high mobility group box 1–induced Rac1/MR activation and downstream inflammatory molecules in endothelial cells. MR antagonists and RAGE aptamers may represent promising therapeutic strategies for preventing AKI and CKD progression.

Background

Although AKI is associated with an increased risk of CKD, the underlying mechanisms remain unclear. High mobility group box 1 (HMGB1), one of the ligands for the receptor for advanced glycation end products (RAGE), is elevated in patients with AKI. We recently demonstrated that the mineralocorticoid receptor (MR) is activated by the RAGE/Rac1 pathway, contributing to chronic renal damage in hypertensive mice. Therefore, this study investigated the role of the HMGB1/RAGE/MR pathway in AKI and progression to CKD.

Methods

We performed a mouse model of renal ischemia–reperfusion (I/R) with or without MR antagonist (MRA). In vitro experiments were conducted using cultured endothelial cells to examine the interaction between the HMGB1/RAGE and Rac1/MR pathways.

Results

In renal I/R injury mice, renal MR activation was associated with elevated serum HMGB1, renal RAGE, and activated Rac1, all of which were suppressed by MRA. Renal I/R injury led to renal dysfunction, tubulointerstitial injury, and increased expressions of inflammation and fibrosis mediators, which were ameliorated by MRA. In vitro , RAGE aptamer or MRA inhibited HMGB1-induced Rac1/MR activation and upregulation of monocyte chemoattractant protein 1 and NF-κB expressions. Seven days after I/R injury, renal I/R injury mice developed CKD, whereas MRA prevented renal injury progression and decreased the mortality rate. Furthermore, in case of MRA treatment even after I/R injury, attenuated renal dysfunction compared with untreated mice was also observed.

Conclusions

Our findings suggest that HMGB1 may play a crucial role in AKI and CKD development by activating the Rac1/MR pathway through interactions with RAGE.

Acute kidney disease in mice is associated with early cardiovascular dysfunction

Acute kidney injury (AKI) and chronic kidney disease (CKD) are major health concerns due to their increasing incidence and high mortality. They are interconnected syndromes; AKI without recovery evolves into acute kidney disease (AKD), which can indicate an AKI-to-CKD transition. Both AKI and CKD are associated with a risk of long-term cardiovascular complications, but whether vascular and cardiac dysfunctions can occur as early as the AKD period has not been studied extensively. In a mouse model of kidney injury (KI) with non-recovery, we performed vasoreactivity and echocardiography analyses on days 15 (D15) and 45 (D45) after KI. We determined the concentrations of two major gut-derived protein-bound uremic toxins known to induce cardiovascular toxicity-indoxyl sulfate (IS) and para-cresyl sulfate (PCS)-and the levels of inflammation and contraction markers on D7, D15, and D45. Mice with KI showed acute tubular and interstitial kidney lesions on D7 and D15 and chronic glomerulosclerosis on D45. They showed significant impairment of aorta relaxation and systolic-diastolic heart function, both on D15 and D45. Such dysfunction was associated with downregulation of the expression of two contractile proteins, αSMA and SERCA2a, with a more pronounced effect on D15 than on D45. KI was also followed by a rapid increase in IS and PCS serum concentrations and the expression induction of pro-inflammatory cytokines and endothelial adhesion molecules in serum and cardiovascular tissues. Therefore, these results highlight that AKD leads to early cardiac and vascular dysfunctions. How these dysfunctions could be managed to prevent cardiovascular events deserves further study.

Past, present, and future biomarkers of kidney function and injury: The relationship with antibiotics

Routinely used kidney biomarkers of injury and function such as serum creatinine and urine albumin to creatinine ratio, are neither sensitive nor specific. Future biomarkers are being developed for clinical use and have already been included in guidance from groups such as the U.S. Food and Drug Administration and the Predictive Safety Testing Consortium. These biomarkers have important implications for early identification of kidney injury and more accurate measurement of kidney function. Many antibiotics are either eliminated by the kidney or can cause clinically significant nephrotoxicity. As a result, clinicians should be familiar with new biomarkers of kidney function and injury, their place in clinical practice, and applications for antibiotic dosing.

Omega 3 Fatty Acids Attenuate the Acute Kidney Injury to CKD Transition and Renal Fibrosis: Identification of Antifibrotic Metabolites

Key Points

Omega-3 polyunsaturated fatty acids prevent AKI to CKD transition and renal fibrosis. Eicosapentaenoic acid metabolites 18-hydroxyeicosapentaenoic acid, 17,18-epoxyeicosatetraenoic acid, and 17,18-dihydroxyeicosatetraenoic acid have antifibrotic effects.

Background

AKI is an established risk factor for developing CKD. Recently, the renoprotective effect of omega-3 polyunsaturated fatty acids (ω 3PUFAs) has attracted attention. The aims of this study were to evaluate the effect of ω 3PUFAs on the transition of AKI to CKD and to identify fatty acid active metabolites in renal tissue.

Methods

Two mice models of the AKI to CKD transition (7-week, male) and unilateral ureteral obstruction–induced renal fibrosis (11-week, male) were fed linseed oil, rich in ω 3PUFAs (Lin group), or with soybean oil, low in ω 3PUFAs (Soy group). Renal fatty acids and metabolites composition in mice were measured by liquid chromatography-mass spectrometry. Rat renal fibroblast cells were used for in vitro study.

Results

At day 14 after 35 minutes of bilateral renal ischemia reperfusion, significant increase in survival was observed in the Lin group compared with the Soy group. Using the 30-minute bilateral renal ischemia–reperfusion model (AKI to CKD model), the Lin group showed attenuated renal tissue damage and fibrosis. In addition, the antifibrotic effect of the Lin group was also observed in the unilateral ureteral obstruction renal fibrosis model. In the two mice models, levels of eicosapentaenoic acid (EPA) and its metabolites were significantly elevated in renal tissue of mice fed with Lin. Cultured NRK-49F incubated with EPA and its metabolites 18-hydroxyeicosapentaenoic acid, 17,18-epoxyeicosatetraenoic acid, and 17,18-dihydroxyeicosatetraenoic acid displayed suppressed TGF-β 1–stimulated α -smooth muscle actin protein expression. These effects were suppressed in the presence of an inhibitor of a cytochrome P450 involved in EPA metabolism. This observation suggests that the EPA metabolites have antifibrotic effects.

Conclusions

ω 3PUFAs prevent the AKI to CKD transition and renal fibrosis. Moreover, the EPA metabolites 18-hydroxyeicosapentaenoic acid, 17,18-epoxyeicosatetraenoic acid, and 17,18-dihydroxyeicosatetraenoic acid were found to have antifibrotic effects.

Incidence of Acute Kidney Injury and Associated Mortality among Individuals with Drug-Susceptible Tuberculosis in Uganda

Key Points

AKI is thought to be a rare complication in patients with tuberculosis (TB) infection and is mostly attributed to TB drugs. Our findings show AKI occurs more often than previously thought and approximately 33% of patients with drug-susceptible TB may have kidney dysfunction. According to our study findings, monitoring kidney function should be routine among patients diagnosed with TB even before treatment initiation.

Background

Although tuberculosis (TB) is associated with significant mortality and morbidity, its impact on kidney function is not well understood and is often attributed to anti-TB drugs. We aimed to assess the incidence of AKI in the immediate post-TB diagnosis period in Uganda, a TB/HIV-endemic country in sub-Saharan Africa.

Methods

We included patients enrolled in an observational cohort study of adults diagnosed with drug-susceptible TB followed longitudinally. Adults (≥18 years) without known kidney disease were enrolled between August 2022 and July 2023 at three regional hospitals serving 12.5% of the Ugandan population. Our primary outcome was incidence of Kidney Disease Improving Global Outcomes-defined AKI within 2 weeks of TB diagnosis. Other outcomes included predictors of AKI and its association with 30-day survival.

Results

A total of 156 adults were included. The median age was 39 (interquartile range, 28–53) years, most patients were male (68.6%), and 49.4% had HIV. People with HIV had shorter time to TB diagnosis from symptom onset (21 days; interquartile range, 7–30) compared with HIV-negative participants (60 days; interquartile range, 23–90), P < 0.001. The incidence of AKI was 33.3% (52/156) and was similar between people with and without HIV. Proteinuria or hematuria at enrollment was associated with higher odds of AKI (odds ratio, 2.68; 95% confidence interval, 1.09 to 6.70; P approximately 0.033). AKI was associated with a significant risk of mortality (adjusted hazard ratio, 8.22; 95% confidence interval, 1.94 to 34.72; P approximately 0.004) independent of HIV status.

Conclusions

The overall incidence of AKI in the immediate post-TB diagnosis period is high and associated with increased mortality risk. Our findings suggest that monitoring kidney function should be routine for patients with TB, including before treatment initiation.

CD44 expression in renal tubular epithelial cells in the kidneys of rats with cyclosporine-induced chronic kidney disease

Renal tubular epithelial cell (TEC) injury is the most common cause of drug-induced kidney injury (DIKI). Although TEC regeneration facilitates renal function and structural recovery following DIKI, maladaptive repair of TECs leads to irreversible fibrosis, resulting in chronic kidney disease (CKD). CD44 is specifically expressed in TECs during maladaptive repair in several types of rat CKD models. In this study, we investigated CD44 expression and its role in renal fibrogenesis in a cyclosporine (CyA) rat model of CKD. Seven-week-old male Sprague-Dawley rats fed a low-salt diet were subcutaneously administered CyA (0, 15, or 30 mg/kg) for 28 days. CD44 was expressed in atrophic, dilated, and hypertrophic TECs in the fibrotic lesions of the CyA groups. These TECs were collected by laser microdissection and evaluated by microarray analysis. Gene ontology analysis suggested that these TECs have a mesenchymal phenotype, and pathway analysis identified CD44 as an upstream regulator of fibrosis-related genes, including fibronectin 1 (Fn1). Immunohistochemistry revealed that epithelial and mesenchymal markers of TECs of fibrotic lesions were downregulated and upregulated, respectively, and that these TECs were surrounded by a thickened basement membrane. In situ hybridization revealed an increase in Fn1 mRNA in the cytoplasm of TECs of fibrotic lesions, whereas fibronectin protein was localized in the stroma surrounding these tubules. Enzyme-linked immunosorbent assay revealed increased serum CD44 levels in CyA-treated rats. Collectively, these findings suggest that CD44 contributes to renal fibrosis by inducing fibronectin secretion in TECs exhibiting partial epithelial-mesenchymal transition and highlight the potential of CD44 as a biomarker of renal fibrosis.

Advancing Community Care and Access to Follow-up After Acute Kidney Injury Hospitalization: Design of the AFTER AKI Randomized Controlled Trial

Background

Acute kidney injury (AKI) is a common complication among hospitalized patients with long-term implications including chronic kidney disease (CKD). Although models are available to predict the risk of advanced CKD after AKI, there is limited evidence regarding follow-up for patients with AKI after hospital discharge, resulting in variable follow-up care. A risk-stratified follow-up approach may improve appropriateness and efficiency of management for CKD among patients at risk of declining kidney function following AKI.

Objective

The objective was to compare and evaluate the use of a risk-stratified approach to follow-up care vs usual care for patients with AKI after hospital discharge.

Design

This study was a pragmatic randomized controlled trial.

Setting

This study was conducted in 2 large urban hospitals in Alberta, Canada.

Patients

Hospitalized patients with AKI (KDIGO stage 2 or 3) not previously under the care of a nephrologist, expected to survive greater than 90 days being discharged home.

Measurements

We will evaluate whether guideline-recommended CKD care processes are initiated within 90 days, including statin use, angiotensin-converting enzyme inhibitor (ACEi)/angiotensin II receptor blocker (ARB) use in those with proteinuria or diabetes, and nephrologist follow-up if sustained eGFR <30 mL/min/1.73 m2. We will also assess the feasibility of recruitment and the proportion of patients completing the recommended blood and urine tests at 90 days.

Methods

Patients with AKI will be enrolled and randomized near the time of hospital discharge. In the intervention group, low risk patients will receive information regarding AKI, medium risk patients will additionally receive follow-up guidance sent to their primary care physician, and high-risk patients will additionally receive follow-up with a nephrologist. Participants in the intervention and usual care group will receive a requisition for urine testing and bloodwork at 90 days following hospital discharge. Telephone follow-up will be conducted for all study participants at 90 days and 1 year after hospital discharge. Bivariate tests of association will be conducted to evaluate group differences at the follow-up time points.

Limitations

We expect there may be challenges with recruitment due to the significant co-existence of comorbidity in this population.

Conclusions

If the trial shows a positive effect on these processes for kidney care, it will inform larger-scale trial to determine whether this intervention reduces the incidence of long-term clinical adverse events, including CKD progression, cardiovascular events, and mortality following hospitalization with AKI.

Evidence for long-term efficacy of a membrane filtration device in rural villages in Ghana

Drinking water contaminated by pathogenic micro-organisms increases the risk of infectious gastrointestinal disease which could potentially lead to acute kidney injury and even death, particularly amongst the young and the elderly. Earlier studies have shown a substantial reduction in the incidence of diarrheal disease over a period of one year using a polysulfone membrane water gravity-powered water filtration device. The current report is a continuation of these studies to assess the long-term effects of the innovative method on diarrheal incidence rates over a 4-year follow-up period. This follow-up study monitored the trend of self-reported diarrheal events in all households in the previously studied villages for 5 months, in the last half of each study year, using the same questionnaire utilized in the earlier study. Three villages that had no device yet installed served as controls. We computed monthly diarrheal incidence rates for all study years (standardized to per 100 person-months) and compared these to the pre-device incidence rate in 2018 and in the control group, using the Wilcoxon rank sum exact test. The average diarrheal incidence rates of 1.5 p100pm in 2019, 2.19 p100pm in 2021, and 0.54p100pm in 2022 were significantly different from an earlier study that reported 17.8 p100pm rates before the devices were installed in 2018, (all p-values < 0.05). Concomitantly, self-reported diarrheal infections were substantially higher in the "control villages" not yet having the filtration device installed (80.9, 77.6, and 21.5 per 100 pm). The consistent and large reduction in diarrhea incidence documents the long-term efficacy of the use of the membrane filtration device. This simple water purification method using gravity flow improves public health in remote regions with limited resources.

Self-controlled Case Series Study for Acute Kidney Injury after Starting Proton Pump Inhibitors or Potassium-Competitive Acid Blocker in Patients with Cancer Using a Large Claims Database

To investigate the risk of acute kidney injury (AKI) in patients with cancer following the initiation of proton pump inhibitors (PPIs) and potassium-competitive acid blocker (PCAB), considering sex and anti-cancer drug use. We conducted a self-controlled case-series study using the Japan Medical Data Center claims data from 12422 patients with cancer who were prescribed PPIs or PCAB between January 2017 and December 2019. Considering the timing of PPI or PCAB, control period (days -120 to -1), risk period 1 (days 0 to +30), and risk period 2 (days +31 to +365) were defined. To assess the incidence rate ratio (IRR) and 95% confidence interval (CI) as the risk ratio, we adjusted for anti-cancer drugs to assess the risk of AKI. Additionally, we also examined sex differences to identify the risk of AKI. AKI was observed in risk period 1 [2.05 (1.12-3.72), p = 0.0192], but a slight reduction was noted in risk period 2 [0.60 (0.36-1.00), p = 0.0481]. A sex-specific increase in the risk of AKI was observed only in males during risk period 1 [2.18 (1.10-4.32), p = 0.0260], with a reduction in risk period 2 [0.48 (0.26-0.89), p = 0.0200]. We identified an increased risk of AKI in patients with cancer starting PPIs or PCAB particularly in males within 30 d after PPI or PCAB initiation, emphasizing the need for vigilant monitoring and management of AKI in this patient population.

Relationship between the lower limit of systolic blood pressure target and kidney function decline in advanced chronic kidney disease: an instrumental variable analysis from the REACH-J CKD cohort study

Intensive antihypertensive treatment decreases cardiovascular disease and mortality risks in chronic kidney disease (CKD), whereas extremely low systolic blood pressure (SBP) is associated with worsening kidney function and poor prognosis. Although the SBP variation is particularly large in patients with CKD, the optimal lower limit of SBP target is unclear. In a nationwide, multicenter cohort study of patients with an estimated glomerular filtration rate (eGFR) < 45 mL/min/1.73 m2, we evaluated the association between the eGFR slopes and the lower limit of SBP target at ≥110 mmHg using a linear mixed-effects model and an instrumental variable method. The instrumental variable was calculated as the facility-level percentage of nephrologists who answered in the survey that their lower limit of SBP target was 110 mmHg or higher. A total of 1320 patients (mean age 70 years; 66% men) were included. The mean eGFR slope ± standard deviation over the four years to baseline was -2.48 ± 2.15 mL/min/1.73 m2/year. The instrumental variable for the lower limit of SBP target at ≥110 mmHg (vs. ≤100 mmHg) was associated with less eGFR decline (coefficient: +1.05 mL/min/1.73 m2/year; 95% confidence interval: 0.33-1.77), while unassociated with a history of cardiovascular disease. The renoprotective effect was particularly larger in the subgroups of the elderly and those with a history of cardiovascular disease. In conclusion, the lower limit of SBP target at 110 mmHg or higher was associated with improved eGFR slope, suggesting the importance of aiming at avoiding excessively low SBP in patients with advanced CKD.

Malaria is the leading cause of acute kidney injury among a Zambian paediatric renal service cohort retrospectively evaluated for aetiologies, predictors of the need for dialysis, and outcomes

BACKGROUND

Whilst malaria is a prominent aetiology associated with acute kidney injury (AKI) in many parts of Africa, a shift in the traditional AKI aetiologies has been witnessed in sections of the continent. Additionally, limited access to dialysis worsens patient outcomes in these low-resource settings. This retrospective cross-sectional study aimed to determine the associated aetiologies, predictors of need for dialysis and malaria-associated AKI (MAKI), and outcomes of AKI and dialysis among children evaluated by the renal service in Lusaka, Zambia.

METHODS

The study sampled all children aged 16 years or below, diagnosed with AKI between 2017 and 2021, by the renal unit at the University Teaching Hospitals- Children's Hospital (UTH-CH), and retrospectively abstracted their records for exposures and outcomes. AKI was defined using the Kidney Disease Improving Global Outcomes (KDIGO) 2012 criteria. Frequency and percentage distributions were used to describe the occurrence of AKI aetiologies and treatment outcomes. Predictors of the need for dialysis, MAKI, and poor treatment outcome were identified by using multivariable logistic regression models.

RESULTS

A total of 126 children diagnosed with AKI were included in this study. Malaria was the most frequent aetiology of AKI(61.1% (77/126, 95% Confidence Interval (CI): 52.0%-69.7%)). Of the 126 children with AKI, 74.6% (94) underwent dialysis. Predictors of the need for dialysis were oliguria (p = 0.0024; Odds ratio (OR) = 7.5, 95% CI: 2.1-27.7) and anuria (p = 0.0211; OR = 6.4, 95% CI = 1.3, 30.7). A fifth (18.3%, 23/126) of the children developed chronic kidney disease (CKD), 5.6% (7/126) died and, a year later, 77% (97/126) were lost to follow-up.

CONCLUSION

At UTH-CH, malaria is the most frequent aetiology among children with AKI undergoing dialysis and children from low-medium malaria incidence areas are at risk; a considerable proportion of children with AKI need dialysis and Tenchoff catheter use in AKI is advocated.

MicroRNAs as Biomarkers and Therapeutic Targets for Acute Kidney Injury

Acute kidney injury (AKI) is a clinical syndrome where a rapid decrease in kidney function and/or urine output is observed, which may result in the imbalance of water, electrolytes and acid base. It is associated with poor prognosis and prolonged hospitalization. Therefore, an early diagnosis and treatment to avoid the severe AKI stage are important. While several biomarkers, such as urinary L-FABP and NGAL, can be clinically useful, there is still no gold standard for the early detection of AKI and there are limited therapeutic options against AKI. miRNAs are non-coding and single-stranded RNAs that silence their target genes in the post-transcriptional process and are involved in a wide range of biological processes. Recent accumulated evidence has revealed that miRNAs may be potential biomarkers and therapeutic targets for AKI. In this review article, we summarize the current knowledge about miRNAs as promising biomarkers and potential therapeutic targets for AKI, as well as the challenges in their clinical use.

Neutrophil gelatinase-associated lipocalin: a biochemical marker for acute kidney injury and long-term outcomes in patients presenting to the emergency department

Introduction

Creatinine has limitations in identifying and predicting acute kidney injury (AKI). Our study examined the utility of neutrophil gelatinase-associated lipocalin (NGAL) in predicting AKI in patients presenting to the emergency department (ED), and in predicting the need for renal replacement therapy (RRT), occurrence of major adverse cardiac events (MACE) and all-cause mortality at three months post visit.

Methods

This is a single-centre prospective cohort study conducted at Singapore General Hospital (SGH). Patients presenting to SGH ED from July 2011 to August 2012 were recruited. They were aged ≥21 years, with an estimated glomerular filtration rate <60 mL/min/1.73 m2, and had congestive cardiac failure, systemic inflammatory response syndrome or required hospital admission. AKI was diagnosed by researchers blinded to experimental measurements. Serum NGAL was measured as a point-of-care test.

Results

A total of 784 patients were enrolled, of whom 107 (13.6%) had AKI. Mean serum NGAL levels were raised (P < 0.001) in patients with AKI (670.0 ± 431.9 ng/dL) compared with patients without AKI (490.3 ± 391.6 ng/dL). The sensitivity and specificity of NGAL levels >490 ng/dL for AKI were 59% (95% confidence interval [CI] 49%-68%) and 65% (95% CI 61%-68%), respectively. Need for RRT increased 21% per 100 ng/dL increase in NGAL (P < 0.001), whereas odds of death in three months increased 10% per 100 ng/dL increase in NGAL (P = 0.028). No clear relationship was observed between NGAL levels and MACE.

Conclusion

Serum NGAL identifies AKI and predicts three-month mortality.

Magnitude and associated factors of acute kidney injury among preterm neonates admitted to public hospitals in Bahir Dar city, Ethiopia 2022: cross-sectional study

BACKGROUND

Acute kidney injury is an independent risk factor for morbidity and mortality in critically ill neonates. Although the magnitude of preterm neonates is high and a major risk for acute kidney injury, there is a paucity of information regarding the magnitude and associated factors of acute kidney injury among preterm neonates in the study area. Therefore, the aim of this study was to assess magnitude and associated factors of acute kidney injury among preterm neonates admitted to public hospitals in Bahir Dar city, Ethiopia, 2022.

METHODS

An institutional-based cross-sectional study was conducted among 423 preterm neonates admitted to public hospitals in Bahir Dar city from May 27 to June 27, 2022. Data were entered into Epi Data Version 4.6.0.2 transferred to Statistical Package and Service Solution version 26 for analysis. Descriptive and inferential statistics were employed. A binary logistic regression analysis was done to identify factors associated with acute kidney injury. Model fitness was checked through Hosmer-Lemeshow goodness of fit test. Variables with a p-value < 0.05 were considered as statistically significant in the multiple binary logistic regression analysis.

RESULT

Out of 423 eligible, 416 neonatal charts were reviewed with a response rate of 98.3%.This study revealed that the magnitude of acute kidney injury was 18.27% (95% CI = 15-22). Very low birth weight (AOR = 3.26; 95% CI = 1.18-9.05), perinatal asphyxia (AOR = 2.84; 95%CI = 1.55-5.19), dehydration (AOR = 2.30; 95%CI = 1.29-4.09), chest compression (AOR = 3.79; 95%CI = 1.97-7.13), and pregnancy-induced hypertension (AOR = 2.17; 95%CI = 1.20-3.93) were factors significantly associated with the development of neonatal acute kidney injury.

CONCLUSION

Almost one in five admitted preterm neonates developed acute kidney injury. The odds of acute kidney injury were high among neonates who were very low birth weight, perinataly asphyxiated, dehydrated, recipients of chest compression, and born to pregnancy-induced hypertensive mothers. Therefore, clinicians have to be extremely cautious and actively monitor renal function in those neonatal population in order to detect and treat acute kidney injury as early as possible.

Harm! foul! How acute kidney injury SHReDDs patient futures

PURPOSE OF REVIEW

Transition from acute kidney injury (AKI) to chronic kidney disease (CKD) is increasingly accepted. Less well recognized, but supported by very similar data, is development of disease of other organ systems after AKI. Awareness of other-organ sequelae of AKI may inform efforts to improve the care of patients after AKI.

RECENT FINDINGS

Stroke, hypertension, reproductive risk, dementia, and death (SHReDD) are sequelae, which occur with increased risk relative to that of non-AKI within 6 months-3 years after AKI diagnosis, and which are supported by preclinical/mechanistic study. Adjusted hazard ratios for these sequelae are strikingly similar to that of AKI-CKD, ranging from 1.2 to 3.0. Mechanistic studies suggest kidney-centric mechanisms including sodium regulation, volume status regulation, and the renin-angiotensin system are drivers of long-term, extra-renal, change.

SUMMARY

Further clinical characterization and mechanistic insight is necessary, and may have considerable translational impact. Programs which screen or follow post-AKI patients may increase clinical utility if focus is expanded to include the SHReDD complications.

Clinical Characteristics of Acute Kidney Injury Associated with Tropical Acute Febrile Illness

Tropical acute febrile illness (TAFI) is one of the most frequent causes of acute kidney injury (AKI). The prevalence of AKI varies worldwide because there are limited reports available and different definitions are used. This retrospective study aimed to determine the prevalence, clinical characteristics, and outcomes of AKI associated with TAFI among patients. Patients with TAFI were classified into non-AKI and AKI cases based on the Kidney Disease Improving Global Outcomes (KDIGO) criteria. Of 1019 patients with TAFI, 69 cases were classified as having AKI, a prevalence of 6.8%. Signs, symptoms, and laboratory results were significantly abnormal in the AKI group, including high-grade fever, dyspnea, leukocytosis, severe transaminitis, hypoalbuminemia, metabolic acidosis, and proteinuria. 20.3% of AKI cases required dialysis and 18.8% received inotropic drugs. Seven patients died, all of which were in the AKI group. Risk factors for TAFI-associated AKI were being male (adjusted odds ratio (AOR) 3.1; 95% CI 1.3–7.4), respiratory failure (AOR 4.6 95% CI 1.5–14.1), hyperbilirubinemia (AOR 2.4; 95% CI 1.1–4.9), and obesity (AOR 2.9; 95% CI 1.4–6). We recommend clinicians investigate kidney function in patients with TAFI who have these risk factors to detect AKI in its early stages and offer appropriate management.

Impact of Vancomycin Loading Doses and Dose Escalation on Glomerular Function and Kidney Injury Biomarkers in a Translational Rat Model

Vancomycin-induced kidney injury is common, and outcomes in humans are well predicted by animal models. This study employed our translational rat model to investigate temporal changes in the glomerular filtration rate (GFR) and correlations with kidney injury biomarkers related to various vancomycin dosing strategies. First, Sprague-Dawley rats received allometrically scaled loading doses or standard doses. Rats that received a loading dose had low GFRs and increased urinary injury biomarkers (kidney injury molecule 1 [KIM-1] and clusterin) that persisted through day 2 compared to those that did not receive a loading dose. Second, we compared low and high allometrically scaled vancomycin doses to a positive acute kidney injury control of high-dose folic acid. Rats in both the low- and high-dose vancomycin groups had higher GFRs on all dosing days than the positive-control group. When the two vancomycin groups were compared, rats that received the low dose had significantly higher GFRs on days 1, 2, and 4. Compared to low-dose vancomycin, the KIM-1 was elevated among rats in the high-dose group on dosing day 3. The GFR correlated most closely with the urinary injury biomarker KIM-1 on all experimental days. Vancomycin loading doses were associated with significant losses of kidney function and elevations of urinary injury biomarkers. In our translational rat model, both the degree of kidney function decline and urinary biomarker increases corresponded to the magnitude of the vancomycin dose (i.e., a higher dose resulted in worse outcomes).

Enhancing the expression of a key mitochondrial enzyme at the inception of ischemia-reperfusion injury can boost recovery and halt the progression of acute kidney injury

Hydrodynamic fluid delivery has shown promise in influencing renal function in disease models. This technique provided pre-conditioned protection in acute injury models by upregulating the mitochondrial adaptation, while hydrodynamic injections of saline alone have improved microvascular perfusion. Accordingly, hydrodynamic mitochondrial gene delivery was applied to investigate the ability to halt progressive or persistent renal function impairment following episodes of ischemia-reperfusion injuries known to induce acute kidney injury (AKI). The rate of transgene expression was approximately 33% and 30% in rats with prerenal AKI that received treatments 1 (T1hr) and 24 (T24hr) hours after the injury was established, respectively. The resulting mitochondrial adaptation via exogenous IDH2 (isocitrate dehydrogenase 2 (NADP+) and mitochondrial) significantly blunted the effects of injury within 24 h of administration: decreased serum creatinine (≈60%, p < 0.05 at T1hr; ≈50%, p < 0.05 at T24hr) and blood urea nitrogen (≈50%, p < 0.05 at T1hr; ≈35%, p < 0.05 at T24hr) levels, and increased urine output (≈40%, p < 0.05 at T1hr; ≈26%, p < 0.05 at T24hr) and mitochondrial membrane potential, Δψm, (≈ by a factor of 13, p < 0.001 at T1hr; ≈ by a factor of 11, p < 0.001 at T24hr), despite elevated histology injury score (26%, p < 0.05 at T1hr; 47%, p < 0.05 at T24hr). Therefore, this study identifies an approach that can boost recovery and halt the progression of AKI at its inception.

Impact of intradialytic hypotension on mortality following the transition from continuous renal replacement therapy to intermittent hemodialysis

BACKGROUND

The transition of dialysis modalities from continuous renal replacement therapy (CRRT) to intermittent hemodialysis (iHD) is frequently conducted during the recovery phase of critically ill patients with acute kidney injury. Herein, we addressed the occurrence of intradialytic hypotension (IDH) after this transition, and its association with the mortality risk.

METHODS

A total of 541 patients with acute kidney injury who attempted to transition from CRRT to iHD at Seoul National University Hospital, Korea from 2010 to 2020 were retrospectively collected. IDH was defined as a discontinuation of dialysis because of hemodynamic instability plus a nadir systolic blood pressure <90 mm Hg or a decrease in systolic blood pressure ≥30 mm Hg during the first session of iHD. Odds ratios (ORs) of outcomes, such as in-hospital mortality and weaning from RRT, were measured using a logistic regression model after adjusting for multiple variables.

RESULTS

IDH occurred in 197 patients (36%), and their mortality rate (44%) was higher than that of those without IDH (19%; OR, 2.64; 95% confidence interval [CI], 1.70-4.08). For patients exhibiting IDH, the iHD sessions delayed successful weaning from RRT (OR, 0.62; 95% CI, 0.43-0.90) compared with sessions on those without IDH. Factors such as low blood pressure, high pulse rate, low urine output, use of mechanical ventilations and vasopressors, and hypoalbuminemia were associated with IDH risk.

CONCLUSIONS

IDH occurrence following the transition from CRRT to iHD is associated with high mortality and delayed weaning from RRT.

The Association Between Catheter Type and Dialysis Treatment: A Retrospective Data Analysis at Two U.S.-Based ICUs

Dialysis catheter type may be associated with differences in continuous renal replacement therapy (CRRT) treatment in the critically ill, with potential implications for patient outcomes and healthcare costs.

OBJECTIVES

To evaluate the association between the catheter type and multiple dialysis treatment outcomes among the critically ill.

DESIGN

Retrospective, observational study.

SETTING

Two U.S.-based ICUs.

PARTICIPANTS

Critically ill patients receiving CRRT between April 1, 2018, and July 1, 2020. A total of 1,037 CRRT sessions were analyzed.

MAIN OUTCOMES AND MEASURES

Circuit life, alarm interruption frequency (including a subset of vascular access [VA]-related alarms), termination type (elective vs nonelective), and blood flow rates. Pre- (n = 530) and post-catheter change (n = 507) periods were assessed, and the post-change period was further divided into intervals of pre-COVID (n = 167) and COVID contemporaneous (n = 340) to account for the pandemic's impact.

RESULTS

Compared with pre-change sessions, post-change sessions had 31% longer circuit life (95% CI, 1.14-1.49; p < 0.001), 3% higher blood flow rate (1.01-1.05; p < 0.01), and lower proportion of nonelective terminations (adjusted odds ratio [OR], 0.42 [0.28-0.62]; p < 0.001). There were fewer interruptions for all alarms (adjusted count ratio, 0.95 [0.87-1.05]; p = 0.31) and VA-related alarms (0.80 [0.66-0.96]; p = 0.014). The sessions during COVID period were statistically similar to pre-COVID sessions for all outcomes except a lower proportion of nonelective terminations (adjusted OR, 0.39 [0.22-0.70]; p < 0.01).

CONCLUSIONS

A change in catheter type was associated with longer CRRT sessions with fewer interruptions and unexpected terminations in a population of critical patients.

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.

Causes and outcome of acute kidney injury amongst adults patients in two hospitals of different category in Cameroon; a 5 year retrospective comparative study

Background

Acute kidney injury (AKI) is an under-recognized disorder, which is associated with a high risk for mortality, development of chronic kidney disease (CKD).

Objective

We sought to describe and compare the causes and outcomes of AKI amongst adult patients in Douala general hospital (DGH) and Buea regional hospital (BRH).

Methods

A hospital-based retrospective cohort analytic study was carried from February to April 2021. Convenience sampling was used. We included Patient’s files admitted from January 2016 to December 2020 aged > 18 years, with AKI diagnosed by a nephrologist and recorded values of serum creatinine (sCr) on admission and discharge. Data were analysed using SPSSv26. Chi-square, fisher, median mood’s and regression logistic test were used, values were considered significant at p < 0.05.

Results

Of the 349 files included 217 was from DGH and 132 from BRH. Community acquired AKI were more present in BRH 87.12% (n = 115) than DGH 84.79% (n = 184) (p = 0.001). Stage III AKI was the most common presentation in both hospital. Pre-renal AKI was more common (p = 0.013) in DGH (65.44%, n = 142) than BRH (46.97%, n = 62). Sepsis and volume depletion were more prevalent in urban area with (64.51 and 30.41% vs. 46.21 and 25.75%) while severe malaria was more present in Semi-urban area (8.33% vs. 1.84%, p = 0.011). Complete and partial renal recovery was 64.97% (n = 141) in DGH and 69.69% (n = 92) in BRH (p = 0.061). More patients had dialysis in BRH 73.07% (n = 57) than in DGH 23.33% (n = 21). More patient died in DGH 33.18% (n = 72) died than in BRH 19.70% (n = 26) (p = 0.007). Stage III was significantly associated with non-renal recovery in both DGH (p = 0.036) and BRH (p = 0.009) while acute tubular necrosis was associated with non-renal outcome in DGH (p = 0.037).

Conclusions

AKI was mainly due to sepsis, volume depletion and nephrotoxicity. Complete and partial recovery of kidney function were high in both settings. Patient outcome was poorer in DGH.

Where do you live and what do you do? Two questions that might impact your kidney health

In many cases the social determinants of health need to be assessed through their interaction with environmental factors. This review looks at the impact of physical location and occupation of individuals on their kidney health. It examines the effect of living at high altitude on kidney function and the relationship between extreme cold or hot temperatures and the incidence of kidney injury. It reviews as well the many occupations that have been linked to kidney disease in high-income and low-and-middle-income countries. As a conclusion, this overview proposes preventive recommendations that could be individualized based on weather, altitude, socio-economic level of the country and occupation of the individual.

A bioinspired carbon monoxide delivery system prevents acute kidney injury and the progression to chronic kidney disease

Renal ischemia-reperfusion (IR)-induced tissue hypoxia causes impaired energy metabolism and oxidative stress. These conditions lead to tubular cell damage, which is a cause of acute kidney injury (AKI) and AKI to chronic kidney disease (CKD). Three key molecules, i.e., hypoxia-inducible factor-1α (HIF-1α), AMP-activated protein kinase (AMPK), and nuclear factor E2-related factor 2 (Nrf2), have the potential to protect tubular cells from these disorders. Although carbon monoxide (CO) can comprehensively induce these three molecules via the action of mitochondrial reactive oxygen species (mtROS), the issue of whether CO induces these molecules in tubular cells remains unclear. Herein, we report that CO-enriched red blood cells (CO-RBC) cell therapy, the inspiration for which is the in vivo CO delivery system, exerts a renoprotective effect on hypoxia-induced tubular cell damage via the upregulation of the above molecules. Experiments using a mitochondria-specific antioxidant provide evidence to show that CO-driven mtROS partially contributes to the upregulation of the aforementioned molecules in tubular cells. CO-RBC ameliorates the pathological conditions of IR-induced AKI model mice via activation of these molecules. CO-RBC also prevents renal fibrosis via the suppression of epithelial mesenchymal transition and transforming growth factor-β1 secretion in an IR-induced AKI to CKD model mice. In conclusion, our results confirm that the bioinspired CO delivery system prevents the pathological conditions of both AKI and AKI to CKD via the amelioration of hypoxia inducible tubular cell damage, thereby making it an effective cell therapy for treating the progression to CKD.

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.

Clinical impact of noncontrast percutaneous coronary intervention in patients with acute coronary syndrome

PURPOSE

Contrast-induced acute kidney injury (CI-AKI) is one of the common serious complications of percutaneous coronary intervention (PCI) in patients with acute coronary syndrome (ACS). This study aimed to assess the significance of noncontrast strategy in the setting of ACS.

METHODS

CI-AKI was defined as an increase in serum creatinine of ?0.5 mg/dL or ?1.25 times from the baseline. One-year worsening renal function (WRF) was defined as an increase of ?0.3mg/dL in serum creatinine from the baseline after PCI.

RESULTS

Of 250 ACS patients, 81 were treated with noncontrast PCI. The average doses of contrast medium in the noncontrast and conventional groups were 17 (9?22) ml and 150 (120?200) ml, respectively. CI-AKI was observed in 4 patients (5%) in the noncontrast group and 29 patients (17%) in the conventional group. Noncontrast PCI was associated with a lower incidence of CI-AKI (adjusted odds ratio, 0.26;95% confidence interval [CI], 0.08?0.82). The bootstrap method and inverse probability weighting led to similar results. CI-AKI was associated with a higher incidence of 1-year WRF (adjusted hazard ratio, 2.30;95% CI, 1.12?4.69), while noncontrast PCI was not.

CONCLUSIONS

Noncontrast PCI was associated with the lower incidence of CI-AKI in ACS patients. J. Med. Invest. 69 : 57-64, February, 2022.

Acute Kidney Injury: Incidence, aetiology, management and outcome measures of a Samoan case series

Background

Acute Kidney Injury (AKI) is a major and under-recognised cause of morbidity and mortality worldwide. Low and middle-income countries bear the greatest burden of AKI (85%). There is currently no published literature on AKI from the Pacific Islands. The aim of the present study was to report the incidence, aetiology, management and outcomes measures of AKI from the tertiary referral hospital of Samoa.

Materials and methods

Single-centre prospective observational study. Participants were recruited by the lead investigator from the hospital patient information system. The inclusion criteria for participation was (1) adults (>18 years) admitted to general wards of Tupua Tamasese Meaole (TTM) Hospital with a diagnosis of AKI between December 1, 2019 and May 31, 2020, and (2) serum creatinine level of >200 μmol/L, and (3) compliance with the current Kidney Disease Improving Global Outcomes (KDIGO) criteria for AKI diagnosis. The data collection form was adapted from the International Society for Nephrology - Global Snapshot Project, and recorded demographic and baseline characteristics, precipitating causes of AKI, treatment/management, and outcomes measures.

Results

There was a total of 114 AKI admissions over the study period corresponding to a hospital-based AKI incidence of 26.8 per 1000 admissions per 6 months. 75% of AKI cases were community acquired. The leading causes of AKI were dehydration (79%) and sepsis (64%). More than 40% of cases presented with two or more Non-Communicable Disease co-morbidities. The in-patient mortality rate was 20.2%. In the 3 months following discharge from hospital, 25% of AKI cases had completely resolved, 25% of patients had died, and 18.7% of AKI cases had progressed to chronic kidney disease. The leading causes of mortality were cardiovascular events (35%) and sepsis (35%).

Conclusions

The hospital-based incidence and unfavourable outcomes of AKI are high in Samoa. Greater awareness of this under-recognised condition is warranted among the public, government officers, and health professionals.

•

AKI is an under-recognised cause of morbidity and mortality worldwide

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LMICs bear the greatest global burden of AKI (85%)

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75% of hospital AKI presentations in Samoa are community acquired

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Leading causes of AKI in Samoa are dehydration (79%) and sepsis (64%)

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Over 40% of AKI case presentations in Samoa report at least two NCD co-morbidities

Klotho and Mesenchymal Stem Cells: A Review on Cell and Gene Therapy for Chronic Kidney Disease and Acute Kidney Disease

Chronic kidney disease (CKD) and acute kidney injury (AKI) are public health problems, and their prevalence rates have increased with the aging of the population. They are associated with the presence of comorbidities, in particular diabetes mellitus and hypertension, resulting in a high financial burden for the health system. Studies have indicated Klotho as a promising therapeutic approach for these conditions. Klotho reduces inflammation, oxidative stress and fibrosis and counter-regulates the renin-angiotensin-aldosterone system. In CKD and AKI, Klotho expression is downregulated from early stages and correlates with disease progression. Therefore, the restoration of its levels, through exogenous or endogenous pathways, has renoprotective effects. An important strategy for administering Klotho is through mesenchymal stem cells (MSCs). In summary, this review comprises in vitro and in vivo studies on the therapeutic potential of Klotho for the treatment of CKD and AKI through the administration of MSCs.

Organizational and financial aspects of a continuous renal replacement therapy program

Critically ill patients who develop severe acute kidney injury in the intensive care unit often require treatment with renal replacement therapies (RRTs). This complication is associated with severe morbidity and mortality and high costs, both during hospitalization and postdischarge. This article discusses the operational requirements to develop and conduct a RRT program, as well as the financial implications of this complex form of patient care. The management of these programs must occur in a context where a clear organizational and educational framework and a multidisciplinary team ensures safety, effectiveness, cost-control, and a clear quality control framework.

Cardiorenal Syndrome: An Important Subject in Nephrocardiology

Coexisting dysfunction of heart and kidney, the cardiorenal syndrome, is a common condition and is associated with worsening of outcomes and complexities of diagnostic, preventive, and therapeutic approaches. The knowledge of the physiology of heart and kidney and their interaction with each other and with other organ systems has progressed significantly in recent years, resulting in a better understanding of the pathogenesis of cardiorenal syndrome. A robust knowledge of the pathophysiology and of the latest practical advancements about cardiorenal syndrome is necessary for cardiologists, nephrologists, and other practitioners who provide medical care to the patients with heart and kidney diseases.

Acute kidney injury

Acute kidney injury (AKI) is defined by a sudden loss of excretory kidney function. AKI is part of a range of conditions summarized as acute kidney diseases and disorders (AKD), in which slow deterioration of kidney function or persistent kidney dysfunction is associated with an irreversible loss of kidney cells and nephrons, which can lead to chronic kidney disease (CKD). New biomarkers to identify injury before function loss await clinical implementation. AKI and AKD are a global concern. In low-income and middle-income countries, infections and hypovolaemic shock are the predominant causes of AKI. In high-income countries, AKI mostly occurs in elderly patients who are in hospital, and is related to sepsis, drugs or invasive procedures. Infection and trauma-related AKI and AKD are frequent in all regions. The large spectrum of AKI implies diverse pathophysiological mechanisms. AKI management in critical care settings is challenging, including appropriate volume control, nephrotoxic drug management, and the timing and type of kidney support. Fluid and electrolyte management are essential. As AKI can be lethal, kidney replacement therapy is frequently required. AKI has a poor prognosis in critically ill patients. Long-term consequences of AKI and AKD include CKD and cardiovascular morbidity. Thus, prevention and early detection of AKI are essential.

Acute Kidney Injury and Associated Factors in Intensive Care Units at a Tertiary Hospital in Northern Tanzania

Background

Acute kidney injury (AKI) is a recognized complication in critically ill patients. The epidemiology of AKI varies worldwide, depending on the diagnostic criteria used and the setting. The International Society of Nephrology has called for a reduction in preventable deaths from AKI to zero by the year 2025. It is suspected that the majority of AKI cases are in limited-resource countries, but the true burden of AKI in these settings remains unknown.

Objective

We aimed to determine, using standardized KDIGO (Kidney Disease Improving Global Outcomes) criteria, the prevalence of AKI, associated factors, and clinical characteristics of adult (≥18 years) patients admitted to intensive care units (ICUs) at a tertiary hospital in Tanzania.

Design

Prospective observational study from November 2017 to May 2018.

Methods

In all, 320 patients admitted to medical and surgical ICUs were consecutively enrolled. Baseline, clinical, and laboratory data were collected on admission and during their ICU stay. Serum creatinine and urine output were measured, and KDIGO criteria were used to determine AKI status.

Results

More than half (55.3%) of ICU patients were diagnosed with AKI. Of these, 80% were diagnosed within 24 hours of admission. Acute kidney injury stage 3 accounted for 35% of patients with AKI. Patients with AKI were older, more likely to have cardiovascular comorbidities, and with higher baseline serum levels of creatinine, potassium, universal vital assessment admission scores, and total white cell count ≥12. Sepsis (odds ratio [OR] = 3.81; confidence interval [CI] = 1.21-11.99), diabetes (OR = 2.54; CI = 1.24-5.17), and use of vasopressors (OR = 3.78; CI = 1.36-10.54) were independently associated with AKI in multivariable logistic regression. Less than one-third of those who needed dialysis received it. There was 100% mortality in those who needed dialysis but did not receive (n = 19).

Limitations

Being based at a referral center, the findings do not represent the true burden of AKI in the community.

Conclusion

The prevalence of AKI was very high in ICUs in Northern Tanzania. The majority of patients presented with AKI and were severely ill, suggesting late presentation, underscoring the importance of prioritizing prevention and early intervention. Further studies should explore locally suitable AKI risk scores that could be used to identify high-risk patients in the community health centers from where patients are referred.

Role of Urinary Beta 2 Microglobulin and Kidney Injury Molecule-1 in Predicting Kidney Function at One Year Following Acute Kidney Injury

Background

There is only limited information on the utility of urinary biomarkers in predicting long-term kidney function following acute kidney injury (AKI). The current study assessed whether urinary beta 2 microglobulin/creatinine (B2M/creat) and kidney injury molecule-1/creatinine (KIM-1/creat) ratios, measured in the early recovery phase of AKI, are predictive of kidney function at one year.

Methods

This is a prospective study done in a tertiary care centre in South India, from March 2017 to December 2018. Adult patients who survived an episode of AKI were followed up for one year (n=125). B2M/creat and KIM-1/creat ratio were measured at two weeks and three months following AKI.

Results

In the AKI survivors, the B2M/creat ratio at 2 weeks [18.3mg/g (IQR 2.3, 52.9)] and KIM-1/creat ratio [1.1 µg/g (IQR 0.5, 4.0) at two weeks were higher compared to healthy controls [B2M/creat ratio 0.35 mg/g (0.17,0.58) and KIM-1/creat ratio 0.40 µg/g (0.23,1.00); P=<0.001]. After adjusting for covariates, the eGFR and urinary B2M/creat ratio at two weeks following AKI were predictive of eGFR at one year (P<0.001). KIM-1/ creat ratios were not predictive of eGFR at one year. A urinary B2M/creat ratio of 10.85 at two weeks following AKI had an 85.5% sensitivity (95% CI 74, 93) and 64.3% (95% CI 53, 75) specificity to predict CKD at one year. An eGFR cutoff of 60 mL/min/1.73 m² at two weeks had a sensitivity of 81.8% (95% CI 69, 90) and specificity of 71.4% (95% CI 60, 81) for predicting CKD. The presence of either one criteria (urinary B2M/creat ratio >10.85 (mg/g) or eGFR <60 mL at two weeks) had a sensitivity of 100% (95% CI 94%, 100%) in predicting CKD at one year.

Conclusion

An eGFR <60 mL/min/1.73m² and elevated urinary B2M/creat ratio at two weeks following AKI is predictive of low eGFR at one year. Urinary KIM-1/creat ratios do not predict CKD progression.

Retrospective Study on Acute Kidney Injury among Cholera Patients in an Outbreak in Whitefield, Bengaluru

Introduction

Cholera is gastroenteritis caused by Vibrio cholerae. It presents with vomiting, severe secretory diarrhoea, and dehydration. It can cause severe complications with severe electrolyte imbalances and oligoanuric acute kidney injury due to acute tubular necrosis secondary to dehydration or infection itself. However, cholera presenting with significant proteinuria and acute kidney injury has not been reported. Hence, this study was conducted. Aims and Objectives. This aim of this study was to assess clinical features, treatment, and prognosis of AKI in cholera patients; to correlate proteinuria with AKI in cholera patients; and to compare cholera patients with normal kidney function and those with AKI. Material and Methods. It was a retrospective observational study involving patients with cholera. Information regarding cholera patients with acute kidney injury, proteinuria, and prognosis were collected.

Results

Most of the patients had significant vomiting, moderate-to-severe diarrhoea, dehydration, and hypovolaemic shock. Cholera caused severe complications such as severe electrolyte imbalances including hyponatraemia and hypokalaemia, acute kidney injury, and proteinuria secondary to dehydration or infection. A surprising finding noted was the lack of significant association between the onset of acute kidney injury and usual risk factors such as hypovolaemic shock and dehydration. It was found that proteinuria had influenced the onset of acute kidney injury, but it did not influence recovery. As there was complete recovery in kidney function, none of the cases required kidney biopsy. There was no mortality noted.

Conclusions

This study points towards the rare occurrence of proteinuria and acute kidney injury in Vibrio cholerae infection with spontaneous remission of kidney disease with appropriate therapy.

Acute kidney injury among medical and surgical in-patients in the Cape Coast Teaching Hospital, Cape Coast, Ghana: a prospective cross-sectional study

Background

Acute kidney injury (AKI) is a syndrome associated with high morbidity, mortality and high hospital costs. Despite its adverse clinical and economic effects, only a few studies have reported reliable estimates on the incidence of AKI in sub-Sahara Africa. We assessed the incidence and associated factors of AKI among medical and surgical patients admitted to a tertiary hospital in Ghana.

Methods

A prospective cross-sectional study was conducted among one hundred and forty-five (145) consecutive patients admitted to the medical and the surgical wards at the Cape Coast Teaching Hospital (CCTH), Cape Coast, Ghana from April 2017 to April 2018. Socio-demographic and clinical information were collected using structured questionnaires. AKI was diagnosed and staged with the KDIGO guideline, using admission serum creatinine as baseline kidney function.

Results

The mean age of the study participants was 46.6±17.7 years, whilst the male:female ratio was 68:77. The overall incidence of AKI among the participants was 15.9% (95% CI: 10.33 – 22.84%). Stage 1 AKI occurred in 56.5% of the participants, whilst stages 2 and 3 AKI respectively occurred among 4.1% and 2.8% of respondents. About 20% of the participants in the medical ward developed AKI (n= 15) whilst 12% of those in surgical ward developed AKI (n= 8). Among the participants admitted to the medical ward, 60.0%, 26.7% and 13.3% had stages 1, 2 and 3 AKI respectively. Whilst 50.0%, 25.0% and 25.0% respectively developed stages 1, 2 and 3 AKI in the surgical ward. Medical patients with AKI had hypertension (40%), followed by liver disease (33.3%); 37.5% of surgical inpatients had gastrointestinal (GI) disorders.

Conclusion

The incidence of AKI is high among medical and surgical patients in-patients in the CCTH, Ghana, with hypertension and liver disease as major comorbidities.

Use of Peritoneal Dialysis in Acute Kidney Injury: How Far Away?

Acute kidney injury (AKI) has become a worldwide public health problem, resulting in a high risk of mortality and progression to chronic kidney disease. Peritoneal dialysis (PD) can be an effective renal support for AKI, especially in regions where medical resources are limited, but actually underused. In this article, the current barriers and challenges of use of PD in AKI are discussed, including health strategy and medical resources, PD team organization, and technique-specific factors. Currently, we are just on the starting line of the campaign of acute PD. It is still a long way to the development of PD as a mature treatment in AKI.

Frequency of Risk Factors and Outcome of Hospital-Acquired Acute Kidney Injury

OBJECTIVE

To determine the frequencies of risk factors and the ultimate outcomes of ccute kidney injury (AKI) among hospitalized patients.

MATERIALS AND METHODOLOGY

This prospective, observational study was carried out from September 15, 2018, to March 14, 2019. All admitted patients, both male and female, with AKI, were included. Those with chronic kidney disease (CKD), small size echogenic kidneys (on ultrasonography, performed on admission), and recent history of urological intervention were excluded from the study. All patients were assessed for etiological factors (sepsis, gastroenteritis, surgical, and obstetrical) and outcome (improved, progression to CKD, or expired).

RESULTS

Out of a total of 230, most patients were aged between 20-50 years with a mean age of 38.99 ± 7.61 years. Males were 144 (62.61%) and females were 86 (37.39%). About 78 (33.91%) patients were hypertensive while 65 (28.26%) were diabetic. The cause of hospital-acquired AKI was found to be sepsis in most (71.73%, n=165) of the cases, followed by gastroenteritis (10.00%, n=23), surgical (9.56%, n=22), and obstetric (8.69%, n=20) causes. When the outcome was assessed, 10 (4.35%) patients expired, 154 (66.96%) improved completely, while 66 (28.69%) progressed to CKD.

CONCLUSION

This study has shown that sepsis is the most common cause of AKI in patients admitted to the hospital. So we recommend that proper steps should be taken to ensure adequate hospital care for avoiding such outcomes in hospitalized patients, and further decrease mortality.

Dyschloremia is associated with failure to restore renal function in survivors with acute kidney injury: an observation retrospective study

Dyschloremia is common in critically ill patients. However, little is known about the effects of dyschloremia on renal function in patients with acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT). A total of 483 patients who received CRRT for AKI were selected and divided into three groups according to their serum chloride concentrations at the time of CRRT initiation. At 90 days after initiating CRRT, renal outcome, i.e., non-complete renal recovery, or renal failure, was assessed in the three groups. The hypochloremia group (serum chloride concentrations < 96 mEq/L, n = 60), the normochloremia group (serum chloride concentrations, 96–111 mEq/L, n = 345), and the hyperchloremia group (serum chloride concentrations > 111 mEq/L, n = 78) were classified. The simplified acute physiology score III was higher in the hyperchloremia and hypochloremia groups than in the normochloremia group. Multivariate logistic regression analyses showed that hypochloremia (odds ratio, 5.12; 95% confidence interval [CI], 2.56–10.23; P < 0.001) and hyperchloremia (odds ratio, 2.53; 95% CI, 1.25–5.13; P = 0.01) were significantly associated with non-complete renal recovery. Similar trends were observed for renal failure. This study showed that dyschloremia was independently associated with failure in restoring renal function following AKI.

A meta-analysis of the incidence rate of postoperative acute kidney injury in patients with congenital heart disease

Background

Acute kidney injury (AKI) is a common complication of cardiac surgery. However, the incidence rate of AKI in patients with congenital heart disease (CHD) greatly varies between reports owing to the different definitions used for AKI. Therefore, this study was designed as a meta-analysis aimed at summarizing the incidence rate of AKI in patients with congenital heart disease (CHD) on the basis of different AKI criteria.

Methods

Studies published till April 24, 2020, on the incidence rate of AKI in patients with CHD, were retrieved from electronic databases and printed literature. To pool data from the included studies, the effect size, a combined statistics, was chosen and presented with the incidence rate and 95% confidence interval (CI). Heterogeneity was evaluated using I² statistics and Cochran Q test. The incidence rates obtained from the subgroup analysis according to study location, type of surgery, type of cohort, age, and AKI criteria) were also evaluated to determine the correlation of AKI with these factors. Publication bias was estimated using the Egger test.

Results

Thirty studies, comprising 9925 patients with AKI who had CHD, were included. Overall, the pooled incidence rate of AKI in the patients with CHD was 38.4% (95% CI, 32.0–44.7%). However, the incidence rate was not significantly affected by gender, study location, type of surgery, type of cohort, and AKI criteria. Moreover, age was significantly associated with the incidence of AKI, and the incidence rate was higher in the patients aged < 1 month than in those aged 1 month to 18 years, < 18 years, and ≥ 18 years (P < 0.05).

Conclusions

In this study, the estimated incidence rate of AKI in patients with CHD was 38.4% and may be influenced by age. These findings highlight the importance of further investigation of the specific causes of and effective preventive measures for AKI.

Effect of acute kidney injury on weaning from mechanical ventilation in chronic obstructive pulmonary diseases patients with respiratory failure

Background

Acute kidney injury (AKI) worsens the outcome in mechanically ventilated patients. The occurrence of AKI may have an effect on weaning from mechanical ventilation (MV). The purpose of this work is to study the effect of AKI on weaning from MV for chronic obstructive pulmonary disease (COPD) patients with respiratory failure (RF). The study included 100 mechanically ventilated COPD patients with RF. Patients were classified into group 1, mechanically ventilated COPD patients with type 2 RF who developed AKI, and group 2, mechanically ventilated COPD patients with type 2 RF, who did not develop AKI.

Results

The age of the studied group ranged between 46 and 80 years, and serum creatinine on admission was within normal. There is a significant difference in a serum creatinine level after 2 days and after 1 week of MV in an intensive care unit (ICU) among AKI cases. There is a significant difference in weaning success between AKI and non-AKI patients with much higher weaning success in non-AKI group. Also, there is a significant reduction in glomerular filtration rate (GFR) in AKI patients after 48 h of admission.

Conclusions

AKI is frequent in COPD patients within 48 h of ICU admission and MV increases the risk of AKI in COPD patients.

Public health benefits of water purification using recycled hemodialyzers in developing countries

In rural regions with limited resources, the provision of clean water remains challenging. The resulting high incidence of diarrhea can lead to acute kidney injury and death, particularly in the young and the old. Membrane filtration using recycled hemodialyzers allows water purification. This study quantifies the public health effects. Between 02/2018 and 12/2018, 4 villages in rural Ghana were provided with a high-volume membrane filtration device (NuFiltration). Household surveys were collected monthly with approval from Ghana Health Services. Incidence rates of diarrhea for 5-month periods before and after implementation of the device were collected and compared to corresponding rates in 4 neighboring villages not yet equipped. Data of 1,130 villagers over 10 months from the studied communities were studied. Incidence rates showed a decline following the implementation of the device from 0.18 to 0.05 cases per person-month (ppm) compared to the control villages (0.11 to 0.08 ppm). The rate ratio of 0.27 for the study villages is revised to 0.38 when considering the non-significant rate reduction in the control villages. Provision of a repurposed hemodialyzer membrane filtration device markedly improves health outcomes as measured by diarrhea incidence within rural communities.

Challenges in the Recognition and Management of Acute Kidney Injury by Hospitals in Resource-Limited Settings

Introduction

Acute kidney injury (AKI) is prevalent in low- and middle-income countries (LMIC) and is associated with significant morbidity and mortality, particularly among hospitalized patients. Successful strategies for the prevention and management of AKI in these countries are dependent on the capacity of primary care centers to provide optimal initial management of patients at risk for this disorder.

Methods

From December 2018 to February 2019, using mixed methods, we assessed hospital capacity and the knowledge of clinicians relevant to the prevention, diagnosis, and management of AKI in Rwanda. A checklist based on Kidney Disease: Improving Global Outcomes (KDIGO) guidelines and clinical vignette-based assessment tool were used to assess hospital capacity and provider knowledge base, respectively. Data were analyzed using stata 13 with findings reported as simple frequencies or means with standard deviation. Multivariate analysis was used to assess factors associated with a higher knowledge score among clinicians.

Results

Ten hospitals and 193 health care providers from sites throughout Rwanda participated in the survey. Surveyed hospitals were equipped with basic general medical equipment but were deficient in diagnostic tools and medical supplies that would allow the diagnosis and nondialytic management of AKI. Although 20% of the hospitals could offer hemodialysis services, peritoneal dialysis services were nonexistent. With regard to knowledge base, the health care providers demonstrated significant deficiencies in the diagnosis and management of AKI. The mean knowledge score for all health providers was 6.3 (±1.5) of a maximum of 11, with a mean (±SD) score for doctors, nurses, and midwives of 6.3 ± 2.05, 6.4 ± 1.3, and 6.08 ± 1.2, respectively. On multivariate analysis, the length of clinical experience and age of the respondents were significantly associated with participants’ knowledge score.

Conclusion

This study documents significant barriers to providing optimal management of AKI in primary health care settings in Rwanda, a resource-limited setting. These include lack of specialized medical personnel, significant knowledge gaps among primary health care providers, suboptimal diagnostic capacity, and limited treatment options for detection and management of AKI.

Association of hypoalbuminemia with short-term and long-term mortality in patients undergoing continuous renal replacement therapy

Background

Hypoalbuminemia reflects several pathological conditions, including nutritional deficiencies and chronic inflammation. However, its relationship with short-term and long-term mortality in patients undergoing continuous renal replacement therapy (CRRT) remains unclear. The present study aimed to assess the effect of hypoalbuminemia on mortality in a large cohort of patients undergoing CRRT.

Methods

The study retrospectively reviewed 1,581 patients who underwent CRRT for the treatment of acute kidney injury from 2010 to 2016. The patients were categorized by tertiles of serum albumin levels at CRRT initiation. The odds ratios and hazard ratios for the risk of all-cause mortality were calculated before and after adjustment for multiple covariates.

Results

The mean albumin level was 2.7 ± 0.6 g/dL at CRRT initiation. During a median follow-up period of 14 days (maximum, 4 years), 1,040 patients (65.8%) died. The risk of overall mortality was higher in the first tertile group than in the third tertile group (hazard ratio, 1.9 [1.63-2.21]). When the mortality rate was stratified by timeframe, the risk was steadily higher in the first tertile group than in the third tertile group (odds ratios: 3.0 [2.34-3.87] for 2-week mortality, 2.7 [2.12-3.52] for 1-month mortality, 2.7 [2.08-3.53] for 6-month mortality, and 2.8 [2.11-3.62] for 1-year mortality). Additionally, the rates of intensive care unit mortality and in-hospital mortality were higher in the first tertile group than in the third tertile group.

Conclusion

The initial hypoalbuminemia was independently associated with short-term and long-term mortality in patients undergoing CRRT. Thus, the serum albumin level should be monitored during CRRT.

A systematic review and meta-analysis of acute kidney injury in the intensive care units of developed and developing countries

Objectives

Although the majority of the global population lives in developing countries, most of the epidemiological data related to intensive care unit (ICU) acute kidney injury (AKI) comes from developed countries. This systematic review aims to ascertain the methodology of studies on ICU AKI patients in developing and developed countries, to determine whether epidemiological comparisons between these two settings are possible, and to present a summary estimate of AKI incidence.

Methods

A systematic review of published studies reporting AKI in intensive care units (2005–2015) identified in PubMed, LILACS, and IBECs databases was conducted. We compared developed and developing countries by evaluating study methodology, AKI reference serum creatinine definitions, population characteristics, AKI incidence and mortality. AKI incidence was calculated with a random-effects model.

Results

Ninety-two studies were included, one of which reported data from both country categories: 60 from developed countries (1,057,332 patients) and 33 from developing countries (34,539 patients). In 78% of the studies, AKI was defined by the RIFLE, AKIN or KDIGO criteria. Oliguria had 11 different definitions and reference creatinine 23 different values. For the meta-analysis, 38 studies from developed and 18 from developing countries were selected, with similar AKI incidence: 39.3% and 35.1%, respectively. The need for dialysis, length of ICU stay and mortality were higher in developing countries.

Conclusion

Although patient characteristics and AKI incidence were similar in developed and developing countries, main outcomes were worse in developing country studies. There are significant caveats when comparing AKI epidemiology in developed and developing countries, including lack of standardization of reference serum creatinine, oliguria and the timeframe for AKI assessment. Larger, prospective, multicenter studies from developing countries are urgently needed to capture AKI data from the overall population without ICU access.

Perioperative Acute Kidney Injury

Perioperative organ injury is among the leading causes of morbidity and mortality of surgical patients. Among different types of perioperative organ injury, acute kidney injury occurs particularly frequently and has an exceptionally detrimental effect on surgical outcomes. Currently, acute kidney injury is most commonly diagnosed by assessing increases in serum creatinine concentration or decreased urine output. Recently, novel biomarkers have become a focus of translational research for improving timely detection and prognosis for acute kidney injury. However, specificity and timing of biomarker release continue to present challenges to their integration into existing diagnostic regimens. Despite many clinical trials using various pharmacologic or nonpharmacologic interventions, reliable means to prevent or reverse acute kidney injury are still lacking. Nevertheless, several recent randomized multicenter trials provide new insights into renal replacement strategies, composition of intravenous fluid replacement, goal-directed fluid therapy, or remote ischemic preconditioning in their impact on perioperative acute kidney injury. This review provides an update on the latest progress toward the understanding of disease mechanism, diagnosis, and managing perioperative acute kidney injury, as well as highlights areas of ongoing research efforts for preventing and treating acute kidney injury in surgical patients.

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.