The evolution of public attention in acute kidney injury and continuous renal replacement therapy: trends analysis from 2004 to 2024.

Background: Acute kidney injury (AKI) and the need for Continuous Renal Replacement Therapy (CRRT) are critically important health concerns. This study analyzes global and regional Internet search queries to understand public attention in AKI and CRRT over time. Methods: We used Google Trends™ to analyze search queries for AKI and CRRT from January 2004 to March 2024. The study examined global trends and detailed insights from the United States, including state-by-state breakdowns. We identified patterns, peaks of attention, and temporal trends in public attention, comparing regional variations across the US and top-ranking countries worldwide. Results: Global attention in AKI peaked in October 2022, with Portugal, Zambia, and Spain showing the highest regional attention. Within the United States, peak attention was in February 2008. Tennessee, Pennsylvania, and West Virginia were the top states that paid attention to AKI. Attention in CRRT peaked globally in March 2024. South Korea, Saudi Arabia, and Bahrain have led the global attention to CRRT. In the United States, peak attention was in April 2020. West Virginia, Tennessee, and Kentucky showed the highest state-specific attention in CRRT. Conclusions: This study reveals significant temporal and geographical variations in online search patterns for AKI and CRRT, suggesting evolving public attention to these critical health issues. This knowledge can guide the development of targeted public health initiatives, enhance medical education efforts, and help healthcare systems tailor their approach to improving awareness and outcomes in kidney health across diverse populations.

A Case of Severe Acute Kidney Injury Due to an Antibiotic-Loaded Cement Spacer for Infected Knee Arthroplasty.

The treatment for periprosthetic joint infection frequently involves the placement of a high-dose antibiotic-loaded bone cement spacer (ALCS) into the debrided joint. Typical antibiotics in the spacer include aminoglycosides and vancomycin. It has been believed that systemic absorption of intraarticular antibiotics would be low and early experience suggested that the risk of acute kidney injury (AKI) from ALCS was minimal. However, recent case reports and case series have suggested a risk of acute kidney injury due to antibiotic absorption, though confounding factors are common. We report a case of severe AKI requiring hemodialysis with extremely high systemic tobramycin levels after the placement of an ALCS with increased dosing of antibiotics after previous failure to resolve a periprosthetic joint infection with a prior ALCS. There was no concomitant use of intravenous nephrotoxic antibiotics nor other confounding factors. Despite dialysis, the patient needed urgent removal of the ALCS to control tobramycin levels with subsequent resolution of the AKI. This case highlights the potentially serious nephrotoxicity of ALCS's, the importance of antibiotic type and dosing, and the value of close monitoring after ALCS placement, especially in a patient with chronic kidney disease.

Aquaporin-1 Facilitates Macrophage M1 Polarization by Enhancing Glycolysis Through the Activation of HIF1α in Lipopolysaccharide-Induced Acute Kidney Injury.

This study aimed to investigate how aquaporin 1 (AQP1) modulates hypoxia-inducible factor-1α (HIF1α) to promote glycolysis and drive the M1 polarization of macrophages. Within 12 h post-treatment with LPS to induce acute kidney injury in rats, a significant upregulation of AQP1 and HIF1α protein levels was noted in serum and kidney tissues. This elevation corresponded with a decrease in blood glucose concentrations and an enhancement of glycolytic activity relative to the control group. Furthermore, there was a pronounced reduction in the circulating levels of the anti-inflammatory cytokine IL-10, accompanied by an upregulation in the levels of the pro-inflammatory cytokines IL-6 and TNF-α. The administration of an HIF1α inhibitor reversed these effects, which did not affect the production of AQP1 protein. In cellular assays, AQP1 knockdown mitigated the increase in HIF1α expression induced by LPS. Furthermore, the suppression of HIF1α with PX-478 led to decreased expression levels of Hexokinase 2 (HK2) and Lactate Dehydrogenase A (LDHA), indicating that AQP1 regulates glycolysis through HIF1α. M1 polarization of macrophages was reduced by AQP1 knockdown and was further diminished by the addition of an HIF1α inhibitor. Inhibition of the glycolytic process not only weakened M1 polarization but also promoted M2 polarization, thereby reducing the release of inflammatory cytokines. These findings provide a novel perspective for developing therapeutic strategies that target AQP1 and HIF1α, potentially improving the treatment of sepsis-associated AKI.

Desmopressin use in major cardiac surgery is associated with renal impairment: a retrospective single-center analysis.

BACKGROUND: Desmopressin acetate (1-deamino-8-d-arginine vasopressin-DDAVP) is a analogue of the antidiuretic hormone vasopressin. DDAVP is suggested to reduce bleeding after cardiac surgery using cardiopulmonary bypass. The aim of this study was to determine if DDAVP has any negative impact on renal function leading to acute kidney injury (AKI) and therefore increases the need for renal replacement therapy (RRT). METHODS: We performed a retrospective single institutional cohort analysis of 2,179 patients undergoing elective and urgent cardiac surgery with CPB from 2017 to 2021. Logistic regression analysis was used to investigate any association between DDAVP, the incidence of AKI KDIGO class 3 and the need for RRT, respectively. The model was adjusted for relevant covariates, including preexisting renal impairment, pharmacological hemodynamic support with vasopressors, complexity of the surgery and postoperative lactate. Secondary outcomes included, in hospital mortality and the need for allogenic blood transfusion. RESULTS: A total of 992 (45.5%) patients received DDAVP intraoperatively during surgery or shortly thereafter. The use of DDAVP was associated with a significant increase in in AKI KDIGO class 3 (OR 2.27; 95% CI 1.46-3.55; p < 0,001) and the need for RRT (OR 2.19; 95%CI 1.48-3.24; p < 0,001). Both findings persisted after covariate adjusting. No increased in-hospital mortality was associated with DDAVP. CONCLUSION: In cardiac surgery, the use of DDAVP was associated with an increased rate of server AKI and the requirement for RRT. Given the severity of the potential harm associated with DDAVP, an evidence-based reevaluation is needed to enable an accurate risk and benefit assessment.

Persistent Renal Dysfunction After Acute Kidney Injury Among STEMI Patients Undergoing Primary Coronary Intervention: Prevalence and Predictors.

BACKGROUND: Acute kidney injury (AKI) is a common and serious complication of ST-elevation myocardial infarction (STEMI). AKI and chronic kidney disease (CKD) are highly heterogeneous, leaving a wide gap between them. Therefore, the term acute kidney disease (AKD) was implemented, describing prolonged renal injury between 7 and 90 days. We aimed to evaluate the prevalence and predictors of AKD among STEMI patients. METHODS: This retrospective observational study included 2940 consecutive patients admitted with STEMI between 2008 and 2022. Renal function was assessed upon admission and routinely thereafter. Renal outcomes were evaluated according to KDIGO criteria, with AKD defined as persistent renal injury of between 7 and 90 days. RESULTS: Two hundred and fifty-two subjects with STEMI and AKI were included; of them, 117 (46%) developed AKD. Among baseline CKD patients, higher rates of AKD were observed (60% vs. 46%). KDIGO index ≥ 2 was an independent predictor for AKD in in subjects without baseline CKD (AOR 2.63, 95% CI 1.07-6.53). In subjects with baseline CKD, older age and higher creatinine were independent predictors for AKD. Subjects with AKD had a higher 1-year mortality rate (HR 3.39, 95% CI 1.71-6.72, p < 0.01). This trend was mainly driven by the CKD subpopulation where higher mortality rates for AKD on CKD were observed (HR 5.26, 95% CI 1.83-15.1, p < 0.01). CONCLUSION: AKD is common among STEMI patients with AKI. The presence of CKD and higher KDIGO stage should prompt strict monitoring for early diagnosis, treatment, and prevention of renal function deterioration.

STAT3 blockade ameliorates LPS-induced kidney injury through macrophage-driven inflammation.

BACKGROUND: Signal transducer and activator of transcription 3 (STAT3), a multifaceted transcription factor, modulates host immune responses by activating cellular response to signaling ligands. STAT3 has a pivotal role in the pathophysiology of kidney injury by counterbalancing resident macrophage phenotypes under inflammation conditions. However, STAT3's role in acute kidney injury (AKI), particularly in macrophage migration, and in chronic kidney disease (CKD) through fibrosis development, remains unclear. METHODS: Stattic (a JAK2/STAT3 inhibitor, 5 mg/kg or 10 mg/kg) was administered to evaluate the therapeutic effect on LPS-induced AKI (L-AKI) and LPS-induced CKD (L-CKD), with animals sacrificed 6-24 h and 14 days post-LPS induction, respectively. The immune mechanisms of STAT3 blockade were determined by comparing the macrophage phenotypes and correlated with renal function parameters. Also, the transcriptomic analysis was used to confirm the anti-inflammatory effect of L-AKI, and the anti-fibrotic role was further evaluated in the L-CKD model. RESULTS: In the L-AKI model, sequential increases in BUN and blood creatinine levels were time-dependent, with a marked elevation of 0-6 h after LPS injection. Notably, two newly identified macrophage subpopulations (CD11bhighF4/80low and CD11blowF4/80high), exhibited population changes, with an increase in the CD11bhighF4/80low population and a decrease in the CD11blowF4/80high macrophages. Corresponding to the FACS results, the tubular injury score, NGAL, F4/80, and p-STAT3 expression in the tubular regions were elevated. STAT3 inhibitor injection in L-AKI and L-CKD mice reduced renal injury and fibrosis. M2-type subpopulation with CD206 in CD11blowF4/80high population increased in the Stattic-treated group compared with that in the LPS-alone group in the L-AKI model. Additionally, STAT3 inhibitor reduced inflammation driven by LPS-stimulated macrophages and epithelial cells injury in the co-culture system. Transcriptomic profiling identified 3 common genes in the JAK-STAT, TLR, and TNF signaling pathways and 11 common genes in the LPS with macrophage response. The PI3K-AKT (IL-6, Akt3, and Pik3r1) and JAK-STAT pathways were determined as potential Stattic targets. Further confirmation through mRNA and protein expressions analyses showed that Stattic treatment reduced inflammation in the L-AKI and fibrosis in the L-CKD mice. CONCLUSIONS: STAT3 blockade effectively mitigated inflammation by retrieving the CD11blowF4/80high population, further emphasizing the role of STAT3-associated macrophage-driven inflammation in kidney injury.

This study investigated the role of STAT3 in LPS-induced acute kidney injury (AKI) and its prolonged pathophysiological effect. In a mouse model, blocking STAT3 with Stattic reduced inflammation and fibrosis, decreased the levels of inflammatory and extracellular matrix (ECM) substances, reduced the number of certain immune cells (macrophages), and influenced specific genes related to inflammation. The findings suggest that targeting STAT3 is a promising approach to treat AKI and CKD by controlling the inflammation and the immune response as well as ECM accumulation. This study provides novel insights into AKI and CKD progression and will facilitate the development of new treatments for kidney injuries at various stages.

A Case of Renal Artery Thrombosis With Concurrent Adrenal Hemorrhage in Polycythemia Vera.

Polycythemia vera (PV) is a rare myeloproliferative neoplasm characterized by the clonal proliferation of hematopoietic stem cells, leading to an elevated red blood cell mass. This hyperproliferative state increases blood viscosity and predisposes patients to thrombotic events, which are a significant cause of morbidity and mortality in PV. The diagnosis of PV is typically confirmed through elevated hemoglobin or hematocrit levels, low serum erythropoietin, and the presence of the Janus kinase 2 (JAK2) mutation. Common complications include venous and arterial thromboses, hemorrhage, and transformation to myelofibrosis or acute leukemia. A 68-year-old female with a history of PV and chronic kidney disease (CKD) presented with uremic symptoms in the form of malaise and nausea. Laboratory investigations indicated acute kidney injury (AKI) and hyperkalemia. Imaging evaluation of renal US Doppler revealed renal artery thrombosis and an incidental adrenal hemorrhage. The patient was managed with intravenous heparin and did not receive thrombolytics or thrombectomy. Her renal function did not improve, necessitating the initiation of hemodialysis (HD) during hospitalization. Over the course of the next few weeks, her renal parameters improved and she managed to be discharged from dialysis. The primary goal of this study was to highlight a rare presentation of renal artery thrombosis secondary to polycythemia vera (PV) and discuss the complexities involved in managing the underlying disease and its thrombotic complication, particularly in the presence of concomitant bleeding. Effective management of PV-related thrombosis requires a delicate balance between anticoagulation to prevent further thrombotic events while carefully addressing the risk of hemorrhage.

Clinical Profile and Predictors Affecting Outcome in Community-Acquired Acute Kidney Injury: A 3 Months Follow-Up Study.

Background: Community-Acquired Acute Kidney Injury (CA-AKI) is often a devastating clinical syndrome allied with high hospital mortality. Moreover, only limited prospective data exist on the outcomes of CA-AKI. Hence, this follow-up study was conducted to assess clinical profiles and the factors affecting outcomes in CA-AKI. Materials and Methods: A prospective study enrolling 283 participants was conducted from the year 2021 to 2022. AKI patients defined as per Kidney Disease Improving Global Outcomes (KDIGO) criteria were included. Data were collected on demographics, clinical features, and etiological factors. Patients were followed for three months. Univariate and multinomial analyses were done to predict outcomes. The Cox regression model was fitted to identify predictors of mortality. Results: The mean age of patients was 41.67±16.21 years with male predominance. Most of the patients required non-ICU (81.9%) care. Around 36% and 39.6 % of AKI patients were oliguric and required dialysis, respectively. Most patients had a single etiology, with sepsis being the most common cause. Most patients were in KDIGO stage 3, followed by stage 2. At three months of follow-up, 40.6%, 12.3%, and 4.2% had complete, partial, and non-recovery, respectively, and 30.4% died. Age, single etiology, hepatorenal syndrome, sepsis, requirement of mechanical ventilation and vasopressors, comorbidities and glomerulonephritis were significantly associated with mortality. Conclusion: CA-AKI is significantly associated with higher mortality, even for those patients who require non-ICU care on presentation. This highlights the pressing need for AKI prevention, early detection, and intervention to mitigate reversible risk factors and optimize clinical outcomes.

Rhabdomyolysis and Pigment Nephropathy - An Uncommon Manifestation of Eucalyptus Oil Consumption.

Eucalyptus oil consumption is well known to cause adverse effects on central nervous system like seizures, ataxia and unconsciousness. No antidote is available and treatment is largely supportive. We report a case of rhabdomyolysis with pigment cast nephropathy and acute kidney injury in a young female following eucalyptus oil consumption and its successful management.

Associations between acute kidney injury and bone fractures: a retrospective cohort study.

Background: Acute kidney injury (AKI) is common. An AKI episode may disrupt the normal mineral bone balance maintained by normal kidney function, thereby modifying the risk of developing bone fractures. However, it remains unclear whether an AKI episode is associated with the risk of bone fractures. Methods: Using retrospective cohort study from an Australian Local Health District, we examined the association between an AKI episode and bone fractures using patient data between 2008 and 2017. Time-varying Cox proportional hazards and propensity-matched analysis were used to examine the association. Sensitivity analyses were undertaken to capture the impact of confirmed AKI status and AKI severity. Results: Of 123 426 included patients, 14 549 (12%) had an AKI episode and 12 505 (10%) had a bone fracture. In the unadjusted analysis, AKI was associated with bone fractures [hazard ratio (HR) 1.99, 95% confidence interval (CI) 1.88-2.11]. This association persisted in the adjusted analysis (HR 1.50, 95% CI 1.41-1.59) and propensity-matched dataset (HR 1.71, 95% CI 1.59-1.83). The sensitivity analysis yielded similar results, with the AKI patients having a higher risk of fractures compared with no AKI patients in the adjusted analysis (HR 1.34, 95% CI 1.25-1.43) and in the propensity-matched dataset (HR 1.44, 95% CI 1.33-1.55). Similar results were seen in the subsidiary sensitivity analysis excluding patients without baseline creatinine. We did not find an increased risk of bone fractures with increasing AKI severity (P = .7). Interaction tests demonstrated a significant association between sex and age category with AKI status and fractures, but not CKD stage or osteoporosis. Conclusions: AKI is associated with a greater risk of bone fractures. This could have implications for managing and screening for bone disease in patients post-AKI episode. This association should be examined in other cohorts and populations for verification.

Development and validation of the PHM-CPA model to predict in-hospital mortality for cirrhotic patients with acute kidney injury.

BACKGROUND: The presence of acute kidney injury (AKI) significantly increases in-hospital mortality risk for cirrhotic patients. Early prognosis prediction for these patients is crucial. We aimed to develop and validate a machine learning model for in-hospital mortality prediction for cirrhotic patients with AKI. METHODS: Data from cirrhotic patients with AKI hospitalized at the First Affiliated Hospital of Zhejiang University between January 1, 2013, and December 31, 2020 were used to train and validate an extreme Gradient Boosting model to predict in-hospital mortality risk. The Boruta algorithm was used for variable selection. The optimal model was selected and named as PHM-CPA (Prediction of in-Hospital Mortality for Cirrhotic Patients with AKI). The PHM-CPA model was then externally validated in patients from eICU Collaborative Research Database (eICU-CRD) and Medical Information Mart for Intensive Care III dataset (MIMIC). The predictive performance of PHM-CPA model was compared with that of logistic regression (LR) model and 25 previously reported models. RESULTS: A total of 519 cirrhotic patients with AKI were enrolled in model training cohort, of whom 118 (23%) died during hospitalization. Fifteen variables from common laboratory tests were selected to develop the PHM-CPA model. The PHM-CPA model achieved an AUROC of 0.816 (95% CI, 0.763-0.861) in the internal validation cohort and 0.787 (95% CI, 0.745-0.830) in the external validation cohort. The PHM-CPA model consistently outperformed the LR model and 25 previously reported models. CONCLUSION: We developed and validated the PHM-CPA model, comprising readily available clinical variables, which demonstrated superior performance and calibration in predicting in-hospital mortality for cirrhotic patients with AKI.

Modern CRRT systems are associated with lower risk of hypothermia.

One risk of continuous renal replacement therapy (CRRT) is inadvertent hypothermia (IH), which is defined as a non-therapeutic core temperature decrease below normal. In continuous renal replacement therapy, heat loss will always occur from blood pumped through the dialysis circuit to cooler environment, predisposing for hypothermia. Blood flow and effluent flows are the most important parameters causing heat loss. We investigated and compared the novel TherMax warmer to previous generation technologies during CRRT in a multicenter setting. This was a prospective observational multicenter study with historic single-center controls. The study group consisted of 100 patients in eight Swedish ICUs with clinical indication for CRRT, using the PrisMax platform and TherMax warmer. Both patient and set warmer temperatures were recorded hourly for the first 24 h. The presence of treatment hours in hypothermia (< 36.0 Celsius) and the difference between set warmer temperature and measured patient temperature in the multi-center study cohort were compared to a matched single-center historic control cohort treated with the old Prismaflex platform and adjacent Barkey warmer. In the TherMax group 77/100 (77.0%) of patients, and for controls 26/86 (30.2%) of patients were free of hypothermia (Chi square, p < 0.001). The mean number of hours spent in hypothermia was (mean ± SD) 0.66 ± 1.60 and 6.92 ± 7.79 h in the TherMax and control groups, respectively (Chi square p < 0.001). In the study group the patient temperature was higher than the set temperature on the warmer with a difference of Δ0.47 ± 0.80 °C (minor difference), whereas in the control group the set temperature on the warmer was higher than the patient temperature with a difference of Δ4.55 ± 1.00 °C (over-correction). The novel TherMax warmer technology protected against hypothermia and was significantly more accurate than the Barkey warmer.

Critical Role of S100A9 in Sepsis-associated Acute Kidney Injury: Mechanistic Insights through Pyroptosis Pathway Modulation.

This study investigates the role of S100A9 in sepsis-associated AKI (SA-AKI) through the lens of pyroptosis, a controlled form of cell death mediated by the gasdermin protein family. Using C57BL/6 mice and S100A9 knockout mice subjected to cecal ligation and puncture (CLP), RNA sequencing and bioinformatics analyses revealed differentially expressed genes (DEGs) related to inflammation and immune responses, with notable upregulation of S100A9. Functional enrichment analyses (GO and KEGG) indicated these DEGs are involved in interferon-beta response, immune processes, and cell adhesion. Protein-protein interaction (PPI) network analyses further emphasized S100A9's pivotal role in SA-AKI.Clinical validation measured S100A9 levels in serum and urine samples from SA-AKI patients and healthy volunteers, finding elevated S100A9 levels in the former. In vivo experiments showed that S100A9 knockout mice exhibited reduced kidney injury and inflammation, indicated by lower serum creatinine, urea nitrogen, and inflammatory markers (IL-1ß and IL-18). Histopathological analyses and immunohistochemistry confirmed less renal damage and reduced expression of cleaved IL-1ß and GSDMD-N in S100A9-deficient mice. Electron microscopy and Western blotting validated that S100A9 deficiency mitigates caspase-1-dependent pyroptosis.Cellular experiments with HK-2 cells demonstrated that S100A9 knockdown alleviated LPS-induced cell damage and reduced pyroptosis markers. These findings illuminate S100A9's involvement in NLRP3 inflammasome activation and pyroptosis, suggesting potential therapeutic targets for SA-AKI. Targeting S100A9 may offer new therapeutic avenues, improving outcomes for sepsis-related kidney injury patients. Future research should aim to validate these findings in larger clinical settings.

Modified furosemide responsiveness index and biomarkers for AKI progression and prognosis: a prospective observational study.

BACKGROUND: Modified furosemide responsiveness index (mFRI) is a novel biomarker for assessing diuretic response and AKI progression in patients with early AKI. However, the comparative predictive performance of mFRI and novel renal biomarkers for adverse renal outcomes remains unclear. In a single-center prospective study, we aimed to evaluate the discriminatory abilities of mFRI and other novel renal biomarkers in predicting AKI progression and prognosis in patients with initial mild and moderate AKI (KDIGO stage 1 to 2). RESULTS: Patients with initial mild and moderate AKI within 48 h following cardiac surgery were included in this study. The mFRI, renal biomarkers (including serum or urinary neutrophil gelatinase-associated lipocalin [sNGAL or uNGAL], serum cystatin C, urinary N-acetyl-beta-D-glycosaminidase [uNAG], urinary albumin-to-creatinine ratio) and cytokines (TNF, IL-1ß, IL-2R, IL-6, IL-8, and IL-10) were measured at AKI diagnosis. The mFRI was calculated for each patient, which was defined as 2-hour urine output divided by furosemide dose and body weight. Of 1013 included patients, 154 (15.2%) experienced AKI progression, with 59 (5.8%) progressing to stage 3 and 33 (3.3%) meeting the composite outcome of hospital mortality or receipt of renal replacement therapy (RRT). The mFRI showed non-inferiority or potential superiority to renal biomarkers and cytokines in predicting AKI progression (area under the curve [AUC] 0.80, 95% confidence interval [CI] 0.77-0.82), progression to stage 3 (AUC 0.87, 95% CI 0.85-0.89), and composite outcome of death and receipt of RRT (AUC 0.85, 95% CI 0.82-0.87). Furthermore, the combination of a functional biomarker (mFRI) and a urinary injury biomarker (uNAG or uNGAL) resulted in a significant improvement in the prediction of adverse renal outcomes than either individual biomarker (all P < 0.05). Moreover, incorporating these panels into clinical model significantly enhanced its predictive capacity for adverse renal outcomes, as demonstrated by the C index, integrated discrimination improvement, and net reclassification improvement (all P < 0.05). CONCLUSIONS: As a rapid, cost-effective and easily accessible biomarker, mFRI, exhibited superior or comparable predictive capabilities for AKI progression and prognosis compared to renal biomarkers in cardiac surgical patients with mild to moderate AKI. TRIAL REGISTRATION: Clinicaltrials.gov, NCT04962412. Registered July 15, 2021, https://clinicaltrials.gov/ct2/show/NCT04962412?cond=NCT04962412&draw=2&rank=1 .

An early and stable mouse model of polymyxin-induced acute kidney injury.

BACKGROUND: Polymyxins have been revived as a last-line therapeutic option for multi-drug resistant bacteria and continue to account for a significant proportion of global antibiotic usage. However, kidney injury is often a treatment limiting event with kidney failure rates ranging from 5 to 13%. The mechanisms underlying polymyxin-induced nephrotoxicity are currently unclear. Researches of polymyxin-associated acute kidney injury (AKI) models need to be more standardized, which is crucial for obtaining consistent and robust mechanistic results. METHODS: In this study, male C57BL/6 mice received different doses of polymyxin B (PB) and polymyxin E (PE, also known as colistin) by different routes once daily (QD), twice daily (BID), and thrice daily (TID) for 3 days. We continuously monitored the glomerular filtration rate (GFR) and the AKI biomarkers, including serum creatinine (Scr), blood urea nitrogen (BUN), neutrophil gelatinase-associated lipocalin (NGAL), and kidney injury molecule-1 (KIM-1). We also performed histopathological examinations to assess the extent of kidney injury. RESULTS: Mice receiving PB (35 mg/kg/day subcutaneously) once daily exhibited a significant decrease in GFR and a notable increase in KIM-1 two hours after the first dose. Changes in GFR and KIM-1 at 24, 48 and 72 h were consistent and demonstrated the occurrence of kidney injury. Histopathological assessments showed a positive correlation between the severity of kidney injury and the changes in GFR and KIM-1 (Spearman's rho = 0.3167, P = 0.0264). The other groups of mice injected with PB and PE did not show significant changes in GFR and AKI biomarkers compared to the control group. CONCLUSION: The group receiving PB (35 mg/kg/day subcutaneously) once daily consistently developed AKI at 2 h after the first dose. Establishing an early and stable AKI model facilitates researches into the mechanisms of early-stage kidney injury. In addition, our results indicated that PE had less toxicity than PB and mice receiving the same dose of PB in the QD group exhibited more severe kidney injury than the BID and TID groups.

GSTT1/GSTM1 deficiency aggravated cisplatin-induced acute kidney injury via ROS-triggered ferroptosis.

Introduction: Cisplatin is a widely used chemotherapeutic agent prescribed to treat solid tumors. However, its clinical application is limited because of cisplatin- induced nephrotoxicity. A known complication of cisplatin is acute kidney injury (AKI). Deletion polymorphisms of GSTM1 and GSTT1, members of the glutathione S-transferase family, are common in humans and are presumed to be associated with various kidney diseases. However, the specific roles and mechanisms of GSTM1 and GSTT1 in cisplatin induced AKI remain unclear. Methods: To investigate the roles of GSTM1 and GSTT1 in cisplatin-induced AKI, we generated GSTM1 and GSTT1 knockout mice using CRISPR-Cas9 technology and assessed their kidney function under normal physiological conditions and cisplatin treatment. Using ELISA kits, we measured the levels of oxidative DNA and protein damage, along with MDA, SOD, GSH, and the GSH/GSSG ratio in wild-type and GSTM1/GSTT1 knockout mice following cisplatin treatment. Additionally, oxidative stress levels and the expression of ferroptosis-related proteins in kidney tissues were examined through Western blotting, qPCR, immunohistochemistry, and immunofluorescence techniques. Results: Here, we found that GSTT1 and GSTM1 were downregulated in the renal tubular cells of AKI patients and cisplatin-treated mice. Compared with WT mice, Gstm1/Gstt1-DKO mice were phenotypically normal but developed more severe kidney dysfunction and exhibited increased ROS levels and severe ferroptosis after injecting cisplatin. Discussion: Our study revealed that GSTM1 and GSTT1 can protect renal tubular cells against cisplatin-induced nephrotoxicity and ferroptosis, and genetic screening for GSTM1 and GSTT1 polymorphisms can help determine a standard cisplatin dose for cancer patients undergoing chemotherapy.

Biomarker-based acute kidney injury sub-phenotypes refine risk assessment in children undergoing cardiac surgery.

BACKGROUND: Pediatric cardiac surgery-associated acute kidney injury (CS-AKI) is common with variable association with outcomes, possibly because transient serum creatinine (SCr) elevations are unrelated to kidney disease. Sub-phenotypes of CS-AKI with biomarker integration may provide prognostic enrichment. This study aims to determine if combining early postoperative urine neutrophil gelatinase-associated lipocalin (uNGAL) and SCr into sub-phenotypes strengthens associations with AKI and outcomes. We hypothesized that patients with early subclinical (uNGAL + , SCr -) or damage (uNGAL + , SCr +) CS-AKI would have more postoperative day 2-4 KDIGO-defined AKI and worse clinical outcomes than patients with early functional AKI (uNGAL - , SCr +). METHODS: Two-center prospective observational study evaluating combinations of early uNGAL (8-12 h from ICU admission, ≥ 150 ng/mL) and early postoperative (≤ 8 h of admission) KDIGO SCr-defined AKI to predict CS-AKI on postoperative days (POD) 2-4. Four CS-AKI phenotypes were derived (uNGAL - /SCr - ; uNGAL + /SCr - ; uNGAL - /SCr + and uNGAL + /SCr +). The primary outcome was POD2-4 KDIGO SCr-defined CS-AKI. Secondary outcomes included ventilator and intensive care unit-free days (maximum 28). RESULTS: Four hundred seventy-six patients (median age 4.8 [IQR 1.4-30.4] months, 39% female) were included. POD2-4 AKI occurred in 44 (9.2%). 27% were uNGAL + /SCr - and 0.4% (n = 2) uNGAL + /SCr + . The adjusted odds of POD2-4 AKI was ninefold higher (aOR: 9.09, 95%CI: 3.84-21.53) in uNGAL + /SCr - when compared to uNGAL - /SCr - . uNGAL + /SCr - was associated with fewer ventilator-free (aOR: 0.30, 95%CI: 0.19-0.48) and ICU-free days (aOR: 0.41, 95%CI: 0.26-0.66) when compared to uNGAL - /SCr - . CONCLUSION: Early postoperative uNGAL, regardless of SCr elevation, refines risk assessment for pediatric POD2-4 CS-AKI and associated morbidity, enabling earlier AKI identification and prognostics.

Complex Pathophysiology of Acute Kidney Injury (AKI) in Aging: Epigenetic Regulation, Matrix Remodeling, and the Healing Effects of H2S.

The kidney is an essential excretory organ that works as a filter of toxins and metabolic by-products of the human body and maintains osmotic pressure throughout life. The kidney undergoes several physiological, morphological, and structural changes with age. As life expectancy in humans increases, cell senescence in renal aging is a growing challenge. Identifying age-related kidney disorders and their cause is one of the contemporary public health challenges. While the structural abnormalities to the extracellular matrix (ECM) occur, in part, due to changes in MMPs, EMMPRIN, and Meprin-A, a variety of epigenetic modifiers, such as DNA methylation, histone alterations, changes in small non-coding RNA, and microRNA (miRNA) expressions are proven to play pivotal roles in renal pathology. An aged kidney is vulnerable to acute injury due to ischemia-reperfusion, toxic medications, altered matrix proteins, systemic hemodynamics, etc., non-coding RNA and miRNAs play an important role in renal homeostasis, and alterations of their expressions can be considered as a good marker for AKI. Other epigenetic changes, such as histone modifications and DNA methylation, are also evident in AKI pathophysiology. The endogenous production of gaseous molecule hydrogen sulfide (H2S) was documented in the early 1980s, but its ameliorative effects, especially on kidney injury, still need further research to understand its molecular mode of action in detail. H2S donors heal fibrotic kidney tissues, attenuate oxidative stress, apoptosis, inflammation, and GFR, and also modulate the renin-angiotensin-aldosterone system (RAAS). In this review, we discuss the complex pathophysiological interplay in AKI and its available treatments along with future perspectives. The basic role of H2S in the kidney has been summarized, and recent references and knowledge gaps are also addressed. Finally, the healing effects of H2S in AKI are described with special emphasis on epigenetic regulation and matrix remodeling.

Investigating an appropriate indicator of acute kidney injury for patient prognosis following lung transplantation.

OBJECTIVE: The purpose of this study was to investigate the correlation between different subtypes of acute kidney injury (AKI) and clinical outcomes following lung transplantation (LTx) and to identify a reliable indicator for predicting poor prognosis in the LTx population. METHODS: We retrospectively analyzed the clinical data of 279 LTx patients from August 2016 to March 2023. The AKI subtypes included AKI, persistent AKI on Day 7 (P7-AKI) and Day 14 (P14-AKI) after LTx, and AKI stages. The correlations of these factors with respiratory outcomes, mortality at 90 days, mortality at 1 year and data finalization were assessed, and the risk factors for the selected AKI subtypes were evaluated. RESULTS: AKI occurred in 215 patients (77.1%), with 129 (46.2%) experiencing P7-AKI and 95 (34.1%) experiencing P14-AKI. P7-AKI was associated with more respiratory and mortality outcomes than were AKI and AKI stages, and P7-AKI surpassed P14-AKI in terms of a shorter diagnostic time. After adjusting for age, sex, BMI, type of transplant, transplant diagnosis and comorbidities, P7-AKI independently correlated with increased mortality risk at 90 days [HR 12.312 (95% CI: 2.839-53.402)], 1 year [HR 3.847 (95% CI: 1.840-8.044)], and data finalization [HR 2.010 (95% CI: 1.331-3.033)]. Five variables were identified as independent predictors for P7-AKI, including preoperative body mass index, prothrombin activity, hemoglobin and serum creatinine, and intraoperative colloid administration. CONCLUSION: P7-AKI has been identified as a reliable indicator for predicting adverse outcomes in LTx patients, which may assist healthcare professionals in identifying high-risk individuals.

Impact of No-Clamping Partial Nephrectomy on Early Estimated Glomerular Filtration Rate Preservation.

Incidences of kidney cancers are steadily increasing. The surgical resection of renal tumors remains the treatment of choice, and different techniques provide similar oncological outcomes. Minimally invasive methods, especially partial nephrectomy (PN), have emerged as the preferred method of tumor resection, both in traditional and robot-assisted laparoscopy. PN may be performed as an open or laparoscopic operation. On-clamp PN is a variant of PN that includes the clamping of renal vessels; off-clamp PN is performed without any ischemia. Objectives: To assess the short-term loss of eGFR after on-clamp and off-clamp PN. Methods: Data from 2021 to 2024 were retrospectively collected from a hospital database. The patients included in the study had a diagnosed kidney tumor that was confirmed by MRI or CT imaging. The patients were divided into two groups depending on the type of treatment they received: on-clamp PN or off-clamp PN. Hematocrit (HCT), hemoglobin (Hb) and eGFR were measured and compared. Results: Both groups had comparable preoperative HTC, Hb, and eGFR. eGFR loss 24 h after the procedure was 35.4% lower in the off-clamp group compared to the on-clamp group (p = 0.027). Conclusions: Off-clamp PN is a safe and viable method for kidney tumor resection, both in traditional and robot-assisted laparoscopy. This technique results in a smaller perioperative loss of eGFR, which relates to better short-term functional outcomes than on-clamp PN.