Toxicity Mechanisms of Gadolinium and Gadolinium-Based Contrast Agents-A Review.

Gadolinium-based contrast agents (GBCAs) have been used for more than 30 years to improve magnetic resonance imaging, a crucial tool for medical diagnosis and treatment monitoring across multiple clinical settings. Studies have shown that exposure to GBCAs is associated with gadolinium release and tissue deposition that may cause short- and long-term toxicity in several organs, including the kidney, the main excretion organ of most GBCAs. Considering the increasing prevalence of chronic kidney disease worldwide and that most of the complications following GBCA exposure are associated with renal dysfunction, the mechanisms underlying GBCA toxicity, especially renal toxicity, are particularly important. A better understanding of the gadolinium mechanisms of toxicity may contribute to clarify the safety and/or potential risks associated with the use of GBCAs. In this work, a review of the recent literature concerning gadolinium and GBCA mechanisms of toxicity was performed.

The association between systemic inflammatory response index and contrast-associated acute kidney injury in patients undergoing elective percutaneous coronary intervention.

BACKGROUND: The systemic inflammatory response index (SIRI), served as a novel inflammatory biomarker, is the synthesis of neutrophils, monocytes and lymphocytes. AIMS: We hypothesized that SIRI has predictive value for contrast-associated acute kidney injury (CA-AKI) and long-term mortality in patients undergoing elective percutaneous coronary intervention (PCI). METHODS: We retrospectively observed 5685 patients undergoing elective PCI from January 2012 to December 2018. Venous blood samples were collected to obtain the experimental data on the day of admission or the morning of the next day. SIRI = neutrophil count × monocyte count/lymphocyte count. CA-AKI was defined as an increase of 50% or 0.3 mg/dl in SCr from baseline within 48 h after contrast exposure. RESULTS: The incidence of CA-AKI was 6.1% (n = 352). The best cutoff value of SIRI for predicting CA-AKI was 1.39, with a sensitivity of 52.3% and a specificity of 67.3%. [AUC: 0.620, 95% confidence interval (CI): 0.590-0.651, p < 0.001]. After adjusting for potential confounders, multivariate analysis showed that the high SIRI group (SIRI > 1.39) was a strong independent predictor of CA-AKI in patients undergoing elective PCI compared with the low SIRI group (SIRI ≤ 1.39) (odds ratio = 1.642, 95% CI: 1.274-2.116, p < 0.001). Additionally, COX regression analysis showed that SIRI > 1.39 was significantly associated with long-term mortality at a median follow-up of 2.8 years. [Hazard ratio (HR)=1.448, 95%CI: 1.188-1.765; p < 0.001]. Besides, Kaplan-Meier survival curve also indicated that the cumulative rate of mortality was considerably higher in the high SIRI group. CONCLUSIONS: High levels of SIRI are independent predictors of CA-AKI and long-term mortality in patients undergoing elective PCI.

Evaluating biomarkers for contrast-induced nephropathy following coronary interventions: an umbrella review on meta-analyses.

BACKGROUND: Contrast-induced nephropathy (CIN) is a form of acute kidney injury (AKI) occurring in patients undergoing cardiac catheterization, such as coronary angiography (CAG) or percutaneous coronary intervention (PCI). Although the conventional criterion for CIN detection involves a rise in creatinine levels within 72 h after contrast media injection, several limitations exist in this definition. Up to now, various meta-analyses have been undertaken to assess the accuracy of different biomarkers of CIN prediction. However, the existing body of research lacks a cohesive overview. To address this gap, a comprehensive umbrella review was necessary to consolidate and summarize the outcomes of prior meta-analyses. This umbrella study aimed to offer a current, evidence-based understanding of the prognostic value of biomarkers in predicting CIN. METHODS: A systematic search of international databases, including PubMed, Scopus, and Web of Science, from inception to December 12, 2023, was conducted to identify meta-analyses assessing biomarkers for CIN prediction. Our own meta-analysis was performed by extracting data from the included studies. Sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio were assessed using Meta-Disc and CMA softwares. RESULTS: Twelve studies were ultimately included in the umbrella review. The results revealed that neutrophil gelatinase-associated lipocalin (NGAL) exhibited the highest area under the curve (AUC), followed by cystatin-C, urinary kidney injury molecule-1 (uKIM-1), and brain natriuretic peptide (BNP) with AUCs of 0.91, 0.89, 0.85, and 0.80, respectively. NGAL also demonstrated the highest positive likelihood ratio [effect size (ES): 6.02, 95% CI 3.86-9.40], followed by cystatin-C, uKIM-1, and BNP [ES: 4.35 (95% CI 2.85-6.65), 3.58 (95% CI 2.75-4.66), and 2.85 (95% CI 2.13-3.82), respectively]. uKIM-1 and cystatin-C had the lowest negative likelihood ratio, followed by NGAL and BNP [ES: 0.25 (95% CI 0.17-0.37), ES: 0.25 (95% CI 0.13-0.50), ES: 0.26 (95% CI 0.17-0.41), and ES: 0.39 (0.28-0.53) respectively]. NGAL emerged as the biomarker with the highest diagnostic odds ratio for CIN, followed by cystatin-C, uKIM-1, BNP, gamma-glutamyl transferase, hypoalbuminemia, contrast media volume to creatinine clearance ratio, preprocedural hyperglycemia, red cell distribution width (RDW), hyperuricemia, neutrophil-to-lymphocyte ratio, C-reactive protein (CRP), high-sensitivity CRP, and low hematocrit (P < 0.05). CONCLUSION: NGAL demonstrated superior diagnostic performance, exhibiting the highest AUC, positive likelihood ratio, and diagnostic odds ratio among biomarkers for CIN, followed by cystatin-C, and uKIM-1. These findings underscore the potential clinical utility of NGAL, cystatin-C and uKIM-1 in predicting and assessing CIN.

Prognostic impact and predictors of persistent renal dysfunction in acute kidney injury after percutaneous coronary intervention for acute myocardial infarction.

This study aimed to evaluate the prognostic impact and predictors of persistent renal dysfunction in acute kidney injury (AKI) after an emergency percutaneous coronary intervention (PCI) for acute myocardial infarction (AMI). A total of 877 patients who underwent emergency PCI for AMI were examined. AKI was defined as serum creatinine (SCr) ≥ 0.3 mg/dL or ≥ 50% from baseline within 48 h after PCI. Persistent AKI was defined as residual impairment of SCr ≥ 0.3 mg/dL or ≥ 50% from baseline 1 month after the procedure. The primary outcome was the composite endpoints of death, myocardial infarction, hospitalization for heart failure, stroke, and dialysis. AKI and persistent AKI were observed in 82 (9.4%) and 25 (2.9%) patients, respectively. Multivariate Cox proportional hazards analysis demonstrated that persistent AKI, but not transient AKI, was an independent predictor of primary outcome (hazard ratio, 4.99; 95% confidence interval, 2.30-10.8; P < 0.001). Age > 75 years, left ventricular ejection fraction < 40%, a high maximum creatinine phosphokinase MB level, and bleeding after PCI were independently associated with persistent AKI. Persistent AKI was independently associated with worse clinical outcomes in patients who underwent emergency PCI for AMI. Advanced age, poor cardiac function, large myocardial necrosis, and bleeding were predictors of persistent AKI.

Kidney Injury After Minimal Radiographic Contrast Administration in Patients With Acute Coronary Syndromes.

BACKGROUND: Acute kidney injury (AKI) is common in patients with acute coronary syndromes (ACS) treated by percutaneous coronary intervention. OBJECTIVES: Contrast media (CM) volume minimization has been advocated for prevention of AKI. The DyeVert CM diversion system (Osprey Medical, Inc) is designed to reduce CM volume during coronary procedures. METHODS: In this randomized, single-blind, investigator-driven clinical trial conducted in 4 Italian centers from February 4, 2020 to September 13, 2022, 550 participants with ACS were randomly assigned in a 1:1 ratio to the following: 1) the contrast volume reduction (CVR) group (n = 276), in which CM injection was handled by the CM diversion system; and 2) the control group (n = 274), in which a conventional manual or automatic injection syringe was used. The primary endpoint was the rate of AKI, defined as a serum creatinine (sCr) increase ≥0.3 mg/dL within 48 hours after CM exposure. RESULTS: There were 412 of 550 (74.5%) participants with ST-segment elevation myocardial infarction (211 of 276 [76.4%] in the CVR group and 201 of 274 [73.3%] in the control group). The CM volume was lower in the CVR group (95 ± 30 mL vs 160 ± 23 mL; P < 0.001). Seven participants (1 in the CVR group and 6 in the control group) did not have postprocedural sCr values. AKI occurred in 44 of 275 (16%) participants in the CVR group and in 65 of 268 (24.3%) participants in the control group (relative risk: 0.66; 95% CI: 0.47-0.93; P = 0.018). CONCLUSIONS: CM volume reduction obtained using the CM diversion system is effective for prevention of AKI in patients with ACS undergoing invasive procedures. (REnal Insufficiency Following Contrast MEDIA Administration TriaL IV [REMEDIALIV]: NCT04714736).

Novel use of dynamic MR hydrography to rule out esophageal perforation post atrial fibrillation ablation in a patient with anaphylaxis to gadolinium.

Esophageal thermal injury is one of the most devastating complications of atrial radiofrequency ablation, and its diagnosis can be challenging. In this report, we highlight the novel use of free water as a contrast material to better visualize the esophageal lumen in a patient with anaphylaxis to Iodinated contrast media and Gadolinium who recently underwent atrial fibrillation ablation. This becomes particularly handy in patients with contrast allergy, and further emphasizes the role of multimodality imaging.

Efficacy of nicorandil and ranolazine in prevention of contrast-induced nephropathy in patients with mild-to-moderate renal dysfunction: a randomized controlled trial.

INTRODUCTION: Contrast-induced nephropathy (CIN) is a common complication after percutaneous coronary intervention (PCI). There is conflicting evidence regarding efficacy of nicorandil in CIN prevention. With respect to ranolazine, there is physiological possibility as well as data in animal study regarding its protective effect against CIN; there is, however, no human data till date. AIM AND OBJECTIVES: To assess the efficacy of nicorandil and ranolazine in preventing CIN. The secondary endpoint was to measure difference in postprocedure acute kidney injury (AKI) incidence across groups. Also, patients were followed up till 6 months for major adverse events. MATERIAL AND METHODS: This single-center randomized controlled study included 315 patients of coronary artery disease with mild-to-moderate renal dysfunction undergoing elective PCI. Eligible patients were assigned to either nicorandil (n = 105), ranolazine (n = 105) or control group (n = 105) in 1 : 1 : 1 ratio by block randomization. All enrolled patients were given intravenous sodium chloride at rate of 1.0 mL/kg/h (0.5 mL/kg/h for patients with left ventricular ejection fraction <45%) from 6 h before procedure till 12 h after procedure. Iso-osmolar contrast agent (iodixanol) was used for all patients. In addition to hydration, patients in nicorandil group received oral nicorandil (10 mg, 3 times/d) and those in ranolazine group received oral ranolazine (1000 mg, 2 times/d) 1 day before procedure and for 2 days after PCI. Patients in control group received only hydration. RESULTS: Total number of CIN was 34 (10.7%), which included 19 (18.1%) in control, 8 (7.6%) in nicorandil and 7 (6.6%) in ranolazine group. There was significant association of CIN reduction across groups ( P  = 0.012). On pairwise comparison also, there was significant benefit across control and ranolazine as well as control and nicorandil ( P  < 0.025). There was numerically higher incidence of AKI in controls; the difference, however, did not reach statistical significance after applying Bonferroni correction ( P  = 0.044). Over 6-month follow-up, adverse events were similar across groups. CONCLUSION: While this study adds to existing literature that supports role for nicorandil in CIN prevention, the efficacy of ranolazine in protecting against CIN has been demonstrated in humans for the first time.

P16INK4a deletion alleviates contrast-induced acute kidney injury by ameliorating renal cell apoptosis and suppressing inflammation and oxidative stress.

Contrast-induced acute kidney injury (CI-AKI) is the third leading cause of hospital-acquired acute kidney injury. Cellular senescence is associated with CI-AKI. P16INK4a (p16) is a cell cycle regulator and link to aging and senescence. We found that the expression of p16 was elevated in CI-AKI renal tissues, however its role in CI-AKI remains insufficiently understood. In this study, we used p16 knockout (p16KO) mice and wild-type (WT) littermates to establish CI-AKI mice model to elucidate the impact of p16 on CI-AKI. The results showed that serum creatinine (SCr), blood urea nitrogen (BUN), and serum neutrophil gelatinase-associated lipocalin (NGAL) levels were markedly reduced in p16KO CI-AKI mice. Both immunohistochemistry and western blot analyses confirmed that p16 knockout alleviated renal cell apoptosis. Furthermore, interleukin (IL)-1ß, IL-6, and tumor necrosis factor-α (TNF-α) were attenuated by downregulating NLRP3 and NF-κB inflammasomes. Additionally, ROS levels were diminished via activating Nrf2/Keap-1 pathway in p16KO CI-AKI mice. Collectively, our findings suggest that p16 deletion exerts protective effects against apoptosis, inflammation, and oxidative stress in CI-AKI mice model, p16 deletion might be a potential therapeutic strategy for ameliorating CI-AKI.

Safety of Administering Intravenous CT Contrast Agents Repeatedly or Using Both CT and MRI Contrast Agents on the Same Day: An Animal Study.

OBJECTIVE: To investigate molecular and functional consequences of additional exposures to iodine- or gadolinium-based contrast agents within 24 hours from the initial intravenous administration of iodine-based contrast agents through an animal study. MATERIALS AND METHODS: Fifty-six Sprague-Dawley male rats were equally divided into eight groups: negative control, positive control (PC) with single-dose administration of CT contrast agent, and additional administration of either CT or MR contrast agents 2, 4, or 24 hours from initial CT contrast agent injection. A 12 µL/g of iodinated contrast agent or a 0.47 µL/g of gadolinium-based contrast agent were injected into the tail vein. Serum levels of blood urea nitrogen, creatinine, cystatin C (Cys C), and malondialdehyde (MDA) were measured. mRNA and protein levels of kidney injury molecule-1 (KIM-1) and neutrophil gelatinase-associated lipocalin (NGAL) were evaluated. RESULTS: Levels of serum creatinine (SCr) were significantly higher in repeated CT contrast agent injection groups than in PC (0.21 ± 0.02 mg/dL for PC; 0.40 ± 0.02, 0.34 ± 0.03, and 0.41 ± 0.10 mg/dL for 2-, 4-, and 24-hour interval groups, respectively; P < 0.001). There was no significant difference in the average Cys C and MDA levels between PC and repeated CT contrast agent injection groups (Cys C, P = 0.256-0.362; MDA, P > 0.99). Additional doses of MR contrast agent did not make significant changes compared to PC in SCr (P > 0.99), Cys C (P = 0.262), and MDA (P = 0.139-0.771) levels. mRNA and protein levels of KIM-1 and NGAL were not significantly different among additional CT or MR contrast agent groups (P > 0.05). CONCLUSION: A sufficient time interval, probably more than 24 hours, between repeated contrast-enhanced CT examinations may be necessary to avoid deterioration in renal function. However, conducting contrast-enhanced MRI on the same day as contrast-enhanced CT may not induce clinically significant kidney injury.

A Comparison Between Two Different Definitions of Contrast-Associated Acute Kidney Injury for Long-Term Mortality in Patients with Chronic Kidney Disease Undergoing Coronary Angiography.

Background: Contrast-associated acute kidney injury (CA-AKI) is a prevalent complication following coronary angiography (CAG). However, there is ongoing controversy surrounding its precise definition. Although previous studies have demonstrated the successful application of appropriate definitions in managing high-risk CA-AKI patients, there remains limited research on the association between different definitions and prognosis specifically in patients with chronic kidney disease (CKD). Methods: A total of 4197 CKD patients undergoing coronary angiography (CAG) were included in this study. Two definitions of contrast-associated acute kidney injury (CA-AKI) were used: CA-AKIA, which was defined as an increase of ≥0.5 mg/dL or >25% in serum creatinine (SCr) from baseline within 72 hours after CAG, and CA-AKIB, which was defined as an increase of ≥0.3 mg/dL or >50% in SCr from baseline within 48 hours after CAG. Cox regression analysis was employed to assess the association between these two definitions and long-term mortality. Additionally, population attributable risks (PARs) were calculated to evaluate the impact of CA-AKI definitions on long-term prognosis. Results: During the median follow-up period of 4.70 (2.50-7.78) years, the overall long-term mortality was 23.6%, and the long-term mortality in patients with CA-AKI according to both CA-AKIA and CA-AKIB criteria were 33.5% and 33.8%, respectively. We found that CA-AKIA (HR: 1.45, 95% CI: 1.23-1.70, p<0.001) and CA-AKIB (HR: 1.44, 95% CI: 1.23-1.69, p<0.001) were associated with long-term mortality. The PARs were the highest for CA-AKIA (5.87%), followed by CA-AKIB (5.70%). Conclusion: Contrast-associated acute kidney injury (CA-AKI) is a frequently observed complication in CKD patients undergoing coronary angiography (CAG), and both definitions of CA-AKI are significantly correlated with a poor long-term prognosis. Consequently, in the clinical management of CKD patients, it is crucial to prioritize CA-AKI, irrespective of the specific CA-AKI definition used.

Coexistence of nephrogenic systemic fibrosis and calciphylaxis in a gadolinium-naïve, chronic haemodialysis patient.

We present a case of a man in his 40s who was on haemodialysis for over 20 years presenting with rapidly progressive decline in mobility, associated with fixed flexion deformities of joints and peau d'orange appearance of skin together with areas of ulceration that was concerning for calciphylaxis. Skin biopsies were consistent with both nephrogenic systemic fibrosis and calciphylaxis. He has never had exposure to gadolinium-based contrast agent. His treatment included daily dialysis sessions, which were challenging due to vascular access issues and three times weekly sodium thiosulfate. He rapidly declined in hospital and died within 2 weeks of presentation while being treated for a hospital-acquired pneumonia.

Dynamic Coronary Roadmap versus standard angiography for percutaneous coronary intervention: the randomised, multicentre DCR4Contrast trial.

BACKGROUND: Decreasing the amount of iodinated contrast is an important safety aspect of percutaneous coronary interventions (PCI), particularly in patients with a high risk of contrast-induced acute kidney injury (CI-AKI). Dynamic Coronary Roadmap (DCR) is a PCI navigation support tool projecting a motion-compensated virtual coronary roadmap overlay on fluoroscopy, potentially limiting the need for contrast during PCI. AIMS: This study investigates the contrast-sparing potential of DCR in PCI, compared to standard angiographic guidance. METHODS: The Dynamic Coronary Roadmap for Contrast Reduction (DCR4Contrast) trial is a multicentre, international, prospective, unblinded, stratified 1:1 randomised controlled trial. Patients were randomised to either DCR-guided PCI or to conventional angiography-guided PCI. The primary endpoint was the total volume of iodinated contrast administered, and the secondary endpoint was the number of cineangiography runs during PCI. RESULTS: The study population included 356 randomised patients (179 in DCR and 177 in control groups, respectively). There were no differences in patient demographics, angiographic characteristics or estimated glomerular filtration rate (eGFR) between the two groups. The total contrast volume used during PCI was significantly lower with DCR guidance compared with conventional angiographic guidance (64.6±44.4 ml vs 90.8±55.4 ml, respectively; p<0.001). The total number of cineangiography runs was also significantly reduced in the DCR group (8.7±4.7 vs 11.7±7.6 in the control group; p<0.001). CONCLUSIONS: Compared to conventional angiography-guided PCI, DCR guidance was associated with a significant reduction in both contrast volume and the number of cineangiography runs during PCI. (ClinicalTrials.gov: NCT04085614).

Potential renoprotective effect of SGLT2 inhibitors against contrast-induced AKI in diabetic STEMI patients undergoing primary PCI.

BACKGROUND: It has been demonstrated that there is a significant reduction in the incidence of cardiovascular events, mortality rates, and worsening kidney disease in patients using sodium-glucose cotransporter 2 inhibitors (SGLT2i). However, there is limited information about the effect of SGLT2i on the incidence of contrast-induced acute kidney injury (CI-AKI) in patients undergoing primary percutaneous intervention (pPCI). AIMS: Our research was focused on examining how SGLT2i exposure impacts CI-AKI occurrence in patients with ST-segment elevation myocardial infarction (STEMI) and undergoing pPCI. RESULTS: This retrospective, single-center, case-control study included diabetic patients diagnosed with STEMI who underwent pPCI in a tertiary healthcare center between 2021 and 2022. The study population included SGLT2i users (n = 130) and non-SGLT2i users (n = 165). Inverse probability propensity score weighting and doubly robust estimation were performed to decrease bias and to balance covariate distribution for estimating average treatment for those treated. In a doubly robust inverse probability weighted regression model, in which covariates were balanced, CI-AKI risk was also found to be lower in the SGLT2i-user group (OR: 0.86 [0.76-0.98]; 95% CI; P = 0.028). In addition, ejection fraction, admission creatinine, albumin, and volume of contrast media were found to be independent predictors of CI-AKI in patients presenting with STEMI and undergoing pPCI. CONCLUSION: Our study provides evidence supporting the potential protective effect of SGLT2i against CI-AKI in diabetic patients presenting with STEMI and undergoing pPCI.

Renal function after ductus arteriosus transcatheter closure with or without angiography in very preterm infants.

AIM: Transcatheter closure of the patent ductus arteriosus (TCPDA) is increasingly used in preterm infants as an alternative to surgical ligation. However, clinically ill preterm infants are at risk of contrast nephropathy due to the angiography contrast agents used during the procedure. METHODS: We performed a single-centre before-and-after comparative study in VLBW infants to compare the kinetics of serum creatinine during the first 4 days after TCPDA with or without angiography. RESULTS: 69 patients were included and divided into two groups: TCPDA with (contrast+; n = 37) and without (contrast-, n = 32) use of contrast agent. The median dose [range] of contrast agent was 1.0 mL/kg [0.6-2.4 mL/kg]. The change in serum creatinine level between day 2 to 4 after TCPCA and baseline decreased in the contrast- group (-17% [-46%; 18%]), while it increased in the contrast+ group (7% [-24%; 202%] p = 0.002). Comparison of blood urea levels between groups showed similar significant differences. The change in serum creatinine between day 2 to 4 and baseline was significantly correlated with the dose of contrast agent (r2 = 0.682; p < 0.001). CONCLUSION: The use of contrast agents during TCPDA can potentially harm the renal function of very preterm infants. Therefore, we advise minimising or avoiding the use of contrast agents.

Microvascular changes following exposure to iodinated contrast media in vitro. A qualitative comparison to serum creatinine concentrations in post-cardiac catheterization patients.

INTRODUCTION: Contrast-associated acute kidney injury (CA-AKI) is characterized as a loss of renal function following radiological contrast media administration. While all contrast media induce variable changes in microvascular endothelial cells in vitro, only few studies report clinical significance of their findings. A comprehensive assessment of the effect of iodinated contrast media on the renal function in vitro and in vivo is essential. The aim of our study was to morphometrically quantify the effect of two different contrast media (Iobitridol and Iodixanol) on vascular endothelial capillaries in vitro and to analyze their effect on the renal function of patients who underwent cardiac catheterization including the intra-arterial administration of contrast media, by measuring serum creatinine concentration (SCr), a byproduct of muscle metabolism, primarily excreted by the kidneys. Our hypothesis suggests that conducting a qualitative comparison of both outcomes will enable identification of differences and similarities between in vitro and in vivo exposure. MATERIAL AND METHODS: In vitro, co-cultures of human dermal fibroblasts and human dermal microvascular endothelial cells forming capillary beds were exposed to a mixture of phosphate buffered saline and either Iobitridol, Iodixanol, or one of their supplements EDTA or Trometamol for 1.5 or 5 min. Negative control co-cultures were exposed exclusively to phosphate buffered saline. Co-cultures were either directly fixed or underwent a regeneration time of 1, 3 or 7 days. An artificial intelligence software was trained for detection of labeled endothelial capillaries (CD31) on light microscope images and measurements of morphometric parameters. In vivo, we retrospectively analyzed data from patients who underwent intra-arterial administration of contrast media and for whom SCr values were available pre- and post-contrast exposition (1, 3, and 7 days following procedure). Temporal development of SCr and incidence of CA-AKI were assessed. Both exposure types were qualitatively compared. RESULTS: In vitro, Iobitridol, Iodixanol and EDTA induced a strong decrease of two morphometric parameters after 3 days of regeneration. In vivo, a significant increase of SCr and incidence of CA-AKI was observed 3 days following procedure in the post-contrast media patients. No difference was observed between groups. DISCUSSION: Two of the morphometric parameters were inversely proportional to the SCr of the patients. If the endothelial damages observed in vitro occur in vivo, it may result in renal hypoxia, inducing a loss of kidney function clinically translated into an increase of SCr. Further development of our in vitro model could allow closer replication of the internal structure of a kidney and bridge the gap between in vitro studies and their clinical findings.