A comprehensive description of kidney disease progression after acute kidney injury from a prospective, parallel-group cohort study

Guidelines for hospital nephrology assistance from the Brazilian Society of Nephrology (BSN)

The AKI Department of the Brazilian Society of Nephrology (BSN) has prepared a hospital nephrology assistance guide, which encompasses the aspects involved in the nephrologist's role in caring for patients with kidney diseases within the hospital setting. The guide addresses the following main topics: 1) the role of the nephrologist in hospital care; 2) non-dialysis kidney support therapy; 3) technical standards for hospital dialysis care; and 4) outpatient follow-up of patients with acute kidney injury/disease. It provides a detailed description of the nephrologists' main responsibilities, their role in both non-dialysis and dialysis hospital care, as well as describing all available dialysis methods, the required infrastructure, human resources, and records of these procedures. The guide concludes with recommendations for the outpatient follow-up of nephrological patients after hospital discharge. The primary purpose of this BSN guide is to provide support for a better medical and multidisciplinary assistance for nephrologists and other professionals involved in the hospital patient's nephrology care.

Acute kidney injury does not explain sex differences in kidney replacement therapy initiation or death amongst individuals with chronic kidney disease reported to the UK Renal Registry

Background

Why more males than females start kidney replacement therapy (KRT) is incompletely understood. Acute kidney injury (AKI) is a possible factor underlying sex differences in chronic kidney disease (CKD) progression, but previous studies regarding this have been inconclusive. We investigated sex differences in the association between AKI and CKD progression in UK nephrology care.

Methods

This cohort study uses UK Renal Registry data. Adults with CKD stages 4/5 in 14 nephrology centres in England were followed from January 2018 to December 2021. We compared their baseline characteristics by sex and calculated cause specific hazard ratio (HR) for outcomes: time to AKI stage 2/3 (AKI2/3), initiation of chronic KRT and death by all causes.

Results

A total of 15 547 patients were included. Fewer females (43.8%) were seen in renal centres than males (56.2%). During follow-up, 3909 (25.1%) AKI2/3 episodes, 3510 (22.6%) KRT initiations, and 7293 (46.9%) deaths were observed. Males were more likely than females to experience each outcome: AKI2/3 [adjusted HR 1.39, 95% confidence interval (CI) 1.31-1.49], KRT initiation (adjusted HR 1.51, 95% CI 1.39-1.65) and death (adjusted HR 1.11, 95% CI 1.05-1.16). Adjustment for AKI2/3 did not change the association between being male and the higher risk of KRT initiation.

Conclusion

Being male was associated with a higher risk of AKI2/3, KRT initiation and death. Fewer females appeared in nephrology care data than expected from population CKD prevalence. However, no evidence was found to support the hypothesis that AKI2/3 explains the higher KRT initiation rates seen amongst males.

Acute kidney injury in hospitalized patients with real-life analysis of incidence and clinical impact in Italian hospitals (the SIN-AKI study)

Acute Kidney Injury (AKI) is a common condition with significant impact on morbidity, mortality, and healthcare costs. This study explores the epidemiology of AKI, highlighting key factors and outcomes. In a retrospective study we evaluated patients admitted to hospital from 2016 to 2019, excluding those with pre-existing chronic kidney disease (CKD) stages 4-5. Data were extracted from hospital databases, with AKI defined by changes in serum creatinine (sCr) according to KDIGO criteria. Additionally, AKI was classified as "de novo" or as AKI on CKD in the subgroup of patients with available pre-hospital eGFR. Outcomes included mortality, hospital stay duration (LOS), AKI recovery, and persistent AKI. Of 87,087 patients, 17,946 (20.6%) developed AKI. AKI patients were older, with more comorbidities, and had significantly higher mortality (17.7% vs. 4.3%, p < 0.001). AKI was associated with in-hospital mortality (HR 1.23, 95% CI 1.16-1.30), longer LOS, and ICU admission. Mortality increased with AKI severity. Considering the 34,285 patients (39% of the total cohort) with pre-hospital eGFR, AKI occurred in 17.3% patients without previous CKD and in 31.1% of patients with previous CKD. These patients presented higher incidence of ICU admission and mortality. Additionally, 17.6% of AKI patients had persistent kidney dysfunction at discharge, often requiring extended hospitalization and ICU care. The substantial impact of AKI on both short- and potentially long-term health emphasizes the importance of early detection, personalized management, and structured follow-up to enhance outcomes and reduce CKD progression risk.

Sodium-glucose cotransporter 2 inhibitors: a novel approach to prevent the transition from acute kidney injury to chronic kidney disease

PURPOSE OF REVIEW

Acute kidney injury (AKI) often progresses to chronic kidney disease (CKD), yet standardized clinical guidelines for managing this transition remain lacking. Recent studies suggest that sodium-glucose cotransporter 2 inhibitors (SGLT2i) or flozins improve AKI outcomes. Studies on patients living with diabetes post-AKI show flozins reduce mortality, CKD progression, and recurrent AKI, highlighting their potential in mitigating maladaptive kidney repair. We discuss recent preclinical evidence supporting a role of SGLT2i during AKI repair and subsequent CKD.

RECENT FINDINGS

AKI is characterized by endothelial and tubular injury, hypoperfusion, metabolic dysfunction, inflammation, and cell death. SGLT2i restore renal hemodynamics, mitochondrial dysfunction, and reduce oxidative stress, improving recovery following AKI. Additionally, SGLT2i mitigate cell death by counteracting apoptosis and ferroptosis while reducing inflammation through suppression of pro-inflammatory cytokines and inflammasome activation. Beyond AKI, flozins exhibit long-term antifibrotic effects, reducing extracellular matrix deposition even after treatment discontinuation. Preclinical studies demonstrate a sustained protective effect on kidney integrity months after short-term treatment.

SUMMARY

These inhibitors hold promise for broad nephroprotection, with robust biological rationale in maladaptive repair. Further research is needed to optimize their use and establish clinical guidelines for AKI management in both diabetic and nondiabetic populations.

CRISPR/Cas9 based knockout of lncRNA MALAT1 attenuates TGF-β1 induced Smad 2/3 mediated fibrosis during AKI-to-CKD transition

Acute kidney injury (AKI) is a significant clinical issue with potential long-term consequences, as even a single episode can progress to chronic kidney disease (CKD). The AKI-to-CKD transition involves complex pathophysiology, including persistent inflammation, apoptosis, and fibrosis. Long noncoding RNA (lncRNA) metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) has been recognized as a potential therapeutic target for various kidney diseases, including AKI and CKD. In our previous study, we conducted the transcriptomic analysis of lncRNAs in-vitro and animal models of AKI-to-CKD transition and found several dysregulated lncRNAs such as MALAT1, MEG3, NEAT1, MIAT, and H19 in this transition. Among these, we have selected lncRNA MALAT1 to further validate its role in AKI-to-CKD transition as a therapeutic target via a cluster regularly intercept short palindromic protein (CRISPR) associated protein 9 (Cas9)-mediated knockout approach in NRK52E cells. Guide RNAs (gRNAs) were designed to target MALAT1, and the PX459 turbo green fluorescence protein (GFP) plasmid containing MALAT1 gRNA1&2 was transfected into NRK52E cells using CRISPRMAX. Results demonstrated that MALAT1 knockout significantly reduced MALAT1 expression and attenuated Smad2/3-mediated fibrosis by decreasing pSmad2, pSmad2/3, Smad4, vimentin, fibronectin, collagen-I, and α-SMA expression levels, while increasing Smad7, Smurf2, and E-cadherin levels. These findings suggest that targeting the MALAT1/Smad2/3 pathway could be a potential therapeutic target for mitigating fibrosis to prevent AKI-to-CKD transition.

CKD Progression after Acute Kidney Injury: A Secondary Analysis of the Standard versus Accelerated Initiation of Renal Replacement Therapy in Acute Kidney Injury Trial

Key Points

Development or progression of CKD occurred in almost 40% of patients after an episode of severe AKI. Receipt of KRT, regardless of allocation to an accelerated or standard initiation strategy, was associated with development or progression of CKD. This study helps identify a subset of patients at risk of CKD after severe AKI who would benefit from dedicated kidney follow-up after discharge.

Background

CKD is a common complication after AKI. We aimed to evaluate whether a KRT initiation strategy had an effect on CKD progression. Secondarily, we aimed to identify factors that influenced the development or progression of CKD after severe AKI.

Methods

This secondary analysis of the Standard versus Accelerated Initiation of Renal Replacement Therapy in AKI trial included patients with outpatient serum creatinine values available in the year before hospitalization and who were alive at 90 days after randomization. Our main analysis focused on patients who had definitive assessment of kidney function at 90 days after randomization. Predictor markers included patient demographics, comorbidities, markers of acute illness, laboratory values, receipt of KRT, and KRT treatment strategy (accelerated versus standard). The primary outcome was CKD progression, a composite of de novo CKD, defined as new eGFR <60 ml/min per 1.73 m2 if baseline eGFR was ≥60 ml/min; a decline in eGFR ≥25% if baseline eGFR was <60 ml/min; or KRT dependence at day 90. The association of KRT treatment strategy with CKD progression was assessed in an unadjusted mixed-effect logistic regression model.

Results

Of the 401 surviving patients with a baseline serum creatinine, 39% experienced CKD progression. KRT initiation strategy had no effect on CKD progression (accelerated arm [41%], versus the standard arm [38%], odds ratio, 1.13 [95% confidence interval, 0.75 to 1.72]). Receipt of KRT and aortic surgery were the most potent risks of CKD progression.

Conclusions

These findings suggest that CKD progression is common after severe AKI. Risk factors of CKD progression included receipt of KRT and aortic surgery, suggesting that these patients should be prioritized for dedicated kidney follow-up after hospital discharge.

Clinical Trial registry name and registration number:

NCT01557361 .

Epigenetic alterations and memory: key players in the development/progression of chronic kidney disease promoted by acute kidney injury and diabetes

Chronic kidney disease (CKD) is a highly prevalent global public health issue and can progress to kidney failure. Survivors of acute kidney injury (AKI) have an increased risk of progressing to CKD by 8.8-fold and kidney failure by 3.1-fold. Further, 20% to 40% of individuals with diabetes will develop CKD, also known as diabetic kidney disease (DKD). Thus, preventing these kidney diseases can positively impact quality-of-life and life-expectancy outcomes for affected individuals. Frequent episodes of hyperglycemia and renal hypoxia are implicated in the pathophysiology of CKD. Prior periods of hyperglycemia/uncontrolled diabetes can result in development/progression of DKD even after achieving normoglycemia, a phenomenon known as metabolic memory or legacy effect. Similarly, in AKI, hypoxic memory is stored in renal cells even after recovery from the initial AKI episode and can transition to CKD. Epigenetic mechanisms involving DNA methylation, chromatin histone post-translational modifications, and noncoding RNAs are implicated in both metabolic and hypoxic memory, collectively known as "epigenetic memory." This epigenetic memory is generally reversible and provides a therapeutic avenue to ameliorate persistent disease progression due to hyperglycemia and hypoxia and prevent/ameliorate CKD progression. Indeed, therapeutic strategies targeting epigenetic memory are effective at preventing CKD development/progression in experimental models of AKI and DKD. Here, we review the latest in-depth evidence for epigenetic features in DKD and AKI, and in epigenetic memories of AKI-to-CKD transition or DKD development and progression, followed by translational and clinical implications of these epigenetic changes for the treatment of these widespread kidney disorders.

Collagen type III formation but not degradation is associated with risk of kidney disease progression and mortality after acute kidney injury

Background

Acute kidney injury (AKI), a rapid decrease in kidney function, is associated with increased risk of adverse outcomes including development and progression of CKD. Kidney fibrosis is one of the pathological processes central to this AKI-to-CKD transition. Here we investigate the association of biomarkers of collagen type III turnover with adverse outcome following AKI.

Methods

We measured three biomarkers reflecting collagen type III (PRO-C3) formation and degradation (C3M and C3C) in plasma samples collected 1 year after an episode of AKI in 800 patients (392 patients with AKI and 408 non-AKI controls) from the prospective AKI Risk in Derby (ARID) study. Patients were followed until 3 years after the episode of AKI and the following outcomes were assessed: kidney disease progression, mortality, heart failure, cardiovascular events, and hospital readmission.

Results

PRO-C3 levels were elevated in the AKI group compared with the controls (P < .001), whereas C3M and C3C levels were not different between groups. In multivariate models including common risk factors, PRO-C3 was prognostic for kidney disease progression and mortality in the AKI group and for heart failure in the control group. C3M and C3C were not prognostic for any of the investigated outcomes.

Conclusions

Circulating PRO-C3, a biomarker of fibroblast activity, was prognostic for kidney disease progression and mortality when measured 1 year after an episode of AKI. Biomarkers of fibroblast activity may help patient stratification after an episode of AKI by identifying patients at higher risk of kidney disease progression.

Intravenous amino acid for kidney protection: current understanding and future perspectives

Acute kidney injury (AKI) is a common complication in critically ill and perioperative patients and is associated with mortality, morbidity, medical costs, and progression to chronic kidney function. Unfortunately, despite numerous research efforts, until recently, there was no AKI preventive therapy supported by level 1 evidence. Among the several factors that contribute to renal damage, two of the major triggers of AKI development are renal hypoperfusion and renal medullary hypoxia. The intravenous administration of a mixture of amino acids promotes the prevention of AKI through multiple mechanisms: the recruitment of renal functional reserve, increased renal blood flow, and improvements in renal oxygenation. Such mechanisms of action led to increased glomerular filtration rate and urine output in preclinical and pilot clinical studies. To test if these benefits on physiological parameters could be translated into clinically meaningful outcomes, a multicenter, randomized, placebo-controlled, trial was conducted in the cardiac surgery setting. Among 3511 adult patients undergoing elective cardiac surgery with cardiopulmonary bypass, intravenous amino acid administration, compared to placebo, significantly reduced the occurrence of AKI, providing the first level 1 evidence of an effective treatment for AKI prevention. In this review, we provide the epidemiology and pathophysiology of cardiac surgery-associated AKI and the concept of renal functional reserve. Then, we summarize the underlying mechanisms of intravenous amino acid infusion as a renoprotective strategy and its preclinical and clinical evidence. Finally, we discuss the existing evidence gaps and future directions of this promising intervention.

Outcomes of patients with infective endocarditis-associated acute kidney injury: a retrospective cohort study

Background

The outcomes of patients with infective endocarditis (IE)-associated acute kidney injury (AKI) are poorly understood.

Methods

This retrospective cohort study was conducted in a tertiary hospital in China to analyze the short- and long-term outcomes among patients with IE-associated AKI. The risk factors for 90-day mortality, long-term outcomes and kidney non-recovery were analyzed via multivariable logistic regression, the Cox regression, and the Fine-Gray competing risk model, respectively.

Results

Among 294 patients with IE-associated AKI, 14.3% died within 90 days, and the risk factors for 90-day mortality were similar to those identified in the general IE population. Among the 230 AKI survivors in whom 90-day kidney recovery could be assessed, 17.4% did not recover kidney function at 90 days. Kidney non-recovery at 90 days was associated with an increased risk of the long-term composite outcome of mortality, end-stage renal disease or sustained doubling of serum creatinine [hazard ratio (HR) 3.00, 95% confidence interval (CI) 1.19-7.59]. Five variables were related to kidney non-recovery: low baseline estimated glomerular filtration rate (eGFR) (HR 2.52, 95% CI 1.73-3.65), stage of AKI (HR 3.03, 95% CI 2.07-4.42 for stage 3), shock (HR 5.56, 95% CI 3.02-10.22), glomerulonephritis-related AKI (HR 3.04, 95% CI 1.93-4.77) and drug-related AKI (HR 2.77, 95% CI 1.86-4.13).

Conclusion

Patients with IE-associated AKI had a high 90-day mortality, and a substantial proportion of survivors did not recover kidney function at 90 days. Kidney non-recovery at 90 days was associated with adverse long-term outcomes. Low baseline eGFR, severe AKI, shock, drug-related AKI and glomerulonephritis-related AKI were risk factors for kidney non-recovery.

Assessment of Acute Kidney Injury using MRI

There has been growing interest in using quantitative magnetic resonance imaging (MRI) to describe and understand the pathophysiology of acute kidney injury (AKI). The ability to assess kidney blood flow, perfusion, oxygenation, and changes in tissue microstructure at repeated timepoints is hugely appealing, as this offers new possibilities to describe nature and severity of AKI, track the time-course to recovery or progression to chronic kidney disease (CKD), and may ultimately provide a method to noninvasively assess response to new therapies. This could have significant clinical implications considering that AKI is common (affecting more than 13 million people globally every year), harmful (associated with short and long-term morbidity and mortality), and currently lacks specific treatments. However, this is also a challenging area to study. After the kidney has been affected by an initial insult that leads to AKI, complex coexisting processes ensue, which may recover or can progress to CKD. There are various preclinical models of AKI (from which most of our current understanding derives), and these differ from each other but more importantly from clinical AKI. These aspects are fundamental to interpreting the results of the different AKI studies in which renal MRI has been used, which encompass different settings of AKI and a variety of MRI measures acquired at different timepoints. This review aims to provide a comprehensive description and interpretation of current studies (both preclinical and clinical) in which MRI has been used to assess AKI, and discuss future directions in the field. LEVEL OF EVIDENCE: 1 TECHNICAL EFFICACY: Stage 3.

Severe Ethylene Glycol Toxicity: Multidisciplinary Management and Long-Term Renal Implications

Ethylene glycol (C₂H₆O₂), a toxic alcohol commonly found in automotive antifreeze, de-icing solutions, and industrial coolants, can cause severe toxicity when ingested. Due to its sweet taste, it is often consumed accidentally or intentionally, leading to life-threatening consequences such as metabolic acidosis, acute kidney injury (AKI), and mortality. Prompt diagnosis and early treatment with antidotes such as fomepizole or ethanol, combined with hemodialysis, are essential in preventing severe outcomes. This report discusses the case of a 60-year-old male with a history of alcohol use disorder who presented with suspected ethylene glycol poisoning, confirmed by elevated serum levels (513 mg/dL). He received aggressive treatment including fomepizole and multiple hemodialysis sessions, which improved his acid-base status and renal function. Despite initial recovery, survivors of ethylene glycol poisoning remain at risk for developing chronic kidney disease (CKD). Prognostic factors such as severe metabolic acidosis, hyperkalemia, and neurological symptoms influence outcomes including developing CKD, with early intervention improving prognosis. This case emphasizes the importance of diagnosing ethylene glycol poisoning and initiating timely treatment to optimize outcomes and reduce long-term renal complications. Long-term follow-up is crucial for monitoring kidney function, as AKI survivors remain at higher risk for progressive renal decline.

Acute Kidney Injury and Subsequent Cardiovascular Disease: Epidemiology, Pathophysiology, and Treatment

Cardiovascular disease poses a significant threat to individuals with kidney disease, including those affected by acute kidney injury (AKI). In the short term, AKI has several physiological consequences that can impact the cardiovascular system. These include fluid and sodium overload, activation of the renin-angiotensin-aldosterone system and sympathetic nervous system, and inflammation along with metabolic complications of AKI (acidosis, electrolyte imbalance, buildup of uremic toxins). Recent studies highlight the role of AKI in elevating long-term risks of hypertension, thromboembolism, stroke, and major adverse cardiovascular events, though some of this increased risk may be due to the impact of AKI on the course of chronic kidney disease. Current management strategies involve avoiding nephrotoxic agents, optimizing hemodynamics and fluid balance, and considering renin-angiotensin-aldosterone system inhibition or sodium-glucose cotransporter 2 inhibitors. However, future research is imperative to advance preventive and therapeutic strategies for cardiovascular complications in AKI. This review explores the existing knowledge on the cardiovascular consequences of AKI, delving into epidemiology, pathophysiology, and treatment of various cardiovascular complications following AKI.