Contrast media and the kidney: European Society of Urogenital Radiology (ESUR) guidelines

Berberine alleviates contrast-induced nephropathy by activating Akt/Foxo3a/Nrf2 signalling pathway

Contrast-induced nephropathy (CIN) is a condition that causes kidney damage in patients receiving angiography with iodine-based contrast agents. This study investigated the potential protective effects of berberine (BBR) against CIN and its underlying mechanisms. The researchers conducted both in vivo and in vitro experiments to explore BBR's renal protective effects. In the in vivo experiments, SD rats were used to create a CIN model, and different groups were established. The results showed that CIN model group exhibited impaired renal function, severe damage to renal tubular cells and increased apoptosis and ferroptosis. However, BBR treatment group demonstrated improved renal function, decreased apoptosis and ferroptosis. Similar results were observed in the in vitro experiments using HK-2 cells. BBR reduced ioversol-induced apoptosis and ferroptosis, and exerted its protective effects through Akt/Foxo3a/Nrf2 signalling pathway. BBR administration increased the expression of Foxo3a and Nrf2 while decreasing the levels of p-Akt and p-Foxo3a. In conclusion, this study revealed that BBR effectively inhibited ioversol-induced apoptosis and ferroptosis in vivo and in vitro. The protective effects of BBR were mediated through the modulation of Akt/Foxo3a/Nrf2 signalling pathway, leading to the alleviation of CIN. These findings suggest that BBR may have therapeutic potential for protecting against CIN in patients undergoing angiography with iodine-based contrast agents.

Contrast-Induced Encephalopathy: A Rare Complication in a Patient on Peritoneal Dialysis with Several Risk Factors

Major adverse renal and cardiovascular events are reported for high-risk patients undergoing intra-arterial procedures, even if performed with iso-osmolar contrast media (CM). We report a case of contrast-induced encephalopathy (CIE) in a peritoneal dialysis (PD) patient, affected by diabetes, hypertension, and chronic heart failure. A 78-year-old PD patient (diuresis 1,000 mL) underwent a percutaneous angioplasty of the carotid. Immediately after the exam, he developed mental confusion and aphasia. Encephalic computed tomography scan and magnetic resonance imaging excluded ischemia or hemorrhage, but both showed cerebral edema; EEG showed right hemisphere abnormalities, sequelae of recent ischemia. Mannitol and steroids were administered to reduce edema, and additional PD exchange was performed with depurative aim. Within 2 days the patient completely recovered. CIE mimics severe neurological diseases, and it should be considered as differential diagnosis if symptoms come out soon after intra-arterial administration of CM, especially in high-risk patients. Our patient suffered from diabetes, chronic kidney disease, hypertension, chronic heart failure, which are possible contributing factors to the development of CIE. Moreover, this clinical scenario is noteworthy because the development in a patient who underwent PD had never been described before.

Predictive value of CHA2DS2VASC score for contrast-induced nephropathy after primary percutaneous coronary intervention for patients presenting with acute ST-segment elevation myocardial infarction

BACKGROUND

ST-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) are at increased risk for contrast-induced nephropathy (CIN) than elective PCI procedures. Routine calculation of Mehran's score is limited by its complexity and difficulty to memorize. This study evaluated CHA₂DS₂-VASc score predictive utility for CIN in STEMI patients before pPCI.

RESULTS

Consecutive 500 acute STEMI patients presenting to two Egyptian pPCI centers were recruited. Exclusion criteria included cardiogenic shock or known severe renal impairment (baseline serum creatinine ≥ 3 mg/dL) or current or previous indication of hemodialysis. CHA₂DS₂VAS_C score_, Mehran's score, baseline estimated glomerular filtration rate (eGFR), contrast media volume (CMV) and CMV/eGFR ratio were collected for all patients. Post-pPCI CIN (defined as 0.5 mg/dL absolute increase or 25% relative increase of serum creatinine from baseline) and predictive accuracy of CHA₂DS₂VAS_C and Mehran's scores were evaluated. CIN occurred in 35 (7%) of the study group. Values of CHA₂DS₂VAS_C score_, Mehran's score, baseline eGFR, CMV and CMV/eGFR ratio were significantly higher in those who developed CIN compared to those who did not. CHA₂DS₂VAS_C score_, Mehran's score and CMV/eGFR were found to be independent predictors for CIN (P < 0.001 for all). ROC curve analysis revealed that CHA₂DS₂VAS_C ≥ 4 had a superb predictive ability, comparable to Mehran's score, for post-pPCI CIN.

CONCLUSIONS

Being practical, easily memorizable and applicable before proceeding to pPCI, routine CHA₂DS₂VAS_C score calculation in STEMI patients can effectively predict CIN risk and guide preventive and/or therapeutic interventions.

Contrast Medium Use in Computed Tomography for Patients Presenting with Headache: 4-year Retrospective Two-Center Study in Central and Western Regions of Ghana

Background

Contrast medium (CM) administration during computed tomography (CT) enhances the accuracy in the detection and interpretation of abnormalities. Evidence from literature also validate the essence of CM in imaging studies. CT, by virtue of its ubiquity, ease of use, speed, and lower financial footprint, is usually the first investigation in cases of headache. Through a multicenter retrospective analysis, we compared findings of contrast-enhanced CT (CECT) to noncontrast-enhanced CT (NCECT) head examinations among patients presenting with headache.

Methods

A multicenter retrospective analysis of four years' CT head examination data at two radiology centers located in Central and Western Regions of Ghana were reviewed. Records of patients who presented with headache as principal complaint between January 2017 and December 2020 were reviewed. A total of 477 records of patients with headache were identified, retrieved and evaluated. A Chi-square test and Fisher exact test were used to compare the CECT and NCECT groups. Binary logistic regression analysis was computed to assess association between CECT and each CT findings. Statistical significance was considered at p < 0.05 with a 95% confidence interval.

Results

A significant proportion of the patients was females (51.8% in CECT and 60% in NCECT). The NCECT group (40.06 ± 14.76 years) was relatively older than the CECT group (38.43 ± 17.64 years). There was a significant difference between the CECT and NCECT in terms of age (p=0.002) and facility CT was performed (p < 0.0001). The rate of abnormalities was higher in CECT (43.5%, 166/382) compared NCECT (37.9%, 36/95). There was no significant association between CT head findings and contrast enhancement.

Conclusion

CECT examination accounted for 5.6% increase in the detection of head abnormalities. Efforts required to establish local standard operation procedures (SOPs) for contrast medium use especially in CT head examinations. Further studies to improve the knowledge of agents, mechanism of action, and safety of contrast media used among practitioners in Ghana is recommended.

Crosstalk among apoptosis, inflammation, and autophagy in relation to melatonin protective effect against contrast-induced nephropathy in rats

Contrast medium (CM) is a chemical substance that is used for imaging anatomical boundaries and to explore normal and abnormal physiological findings; the use of CM was associated with kidney injury and acute renal failure. Melatonin (M) possesses antioxidant, anti-inflammatory, and antiapoptotic effects in addition to autophagy modulation. This study aimed to investigate the protective effect of M against contrast-induced nephropathy (CIN) and its impact on the crosstalk between inflammasome, apoptosis, and autophagy in CIN. Male albino rats received M (10, 20, and 40 mg/kg/day, intraperitoneally) for 3 days. One hour after the last administration, rats were subjected to CIN induction (10 mg/kg indomethacin, double doses of l-NAME 10 mg/kg, i.v., and meglumine diatrizoate 60% 6 mL/kg, i.v.). CIN-induced kidney damage was evidenced through elevated kidney function biomarkers and induced renal histopathological changes. Pretreatment with M caused a significant decrease in nephrotoxicity biomarkers and histopathological alterations. Moreover, CIN-induced oxidative stress, NLRP3 inflammasome, and apoptosis were attenuated by M. Furthermore, M modulates autophagy in CIN rats. M inhibits CIN-induced NLRP3-inflammasome activation and apoptosis as well as enhances autophagy.

Predictive value of post-procedural hyponatremia on contrast-induced nephropathy in patients who underwent coronary angiography or percutaneous coronary intervention

OBJECTIVE

Hyponatremia is a prognostic marker for specific pathologies. However, the association between contrast-induced nephropathy (CIN) and post-procedural hyponatremia has not been explored. Our study aims to evaluate the association between hyponatremia developing after contrast media administration and CIN.

MATERIAL AND METHODS

A total number of 236 patients who required nephrology consultation before coronary angiography (CAG) or percutaneous coronary intervention (PCI) because of the high risk for contrast nephropathy, were included. Serum sodium levels were measured at admission and within three consecutive days after contrast media administration.

RESULTS

Hyponatremia was observed in 141patients (59.7%) following angiography. CIN was developed in 149 (63.4%) patients. Among the patients who developed hyponatremia, ejection fraction, serum haemoglobin level and serum albumin level were low whereas, contrast media volume and percentage of the diabetes mellitus were higher. Also, length of hospital stay, percentage of CIN, renal replacement requirement and mortality rate were higher in patients with hyponatremia. In univariable analysis to evaluate the risk factors for CIN, being female gender, age, diabetes mellitus, serum albumin concentration, haemoglobin level, contrast media volume and hyponatremia were associated with development of CIN. Multivariable logistic regression analysis revealed that advanced age, serum albumin concentration and hyponatremia were independent predictors of CIN.

CONCLUSION

Post-procedural hyponatremia was an independent risk factor for CIN in CAG or PCI patients.

A NEW METHOD FOR ESTIMATING INCREASE IN RADIATION DOSE ASSOCIATED WITH IODINATED CONTRAST USE

This work investigates the impact of iodinated contrast medium (ICM) on radiation dose in computed tomography (CT) scans using linear models established through a phantom study. Thermoluminescence dosemeters (TLDs) were calibrated using semi-conductor X-ray dosemeters. An electron density phantom, with a vial containing TLDs and different concentrations of iodinated blood, were scanned at different tube voltages. Irradiated TLD outputs were measured and absorbed dose to iodinated blood calculated. CT numbers (tissue attenuation as measured by Hounsfield units) were plotted against absorbed doses to obtain linear models. Data from 49 real patient scans were used to validate the linear models. At each X-ray energy, CT numbers were linearly correlated with the absorbed doses, that is with the increase of blood iodine concentration, the CT number increased and the absorbed dose increased accordingly. ICM can cause an increase of organ dose; the average dose increases were 31.8 ± 8.9% for thyroid, 37.1 ± 9.2% for cardiac muscle, 77.7 ± 14.0% for cardiac chamber, 7.1 ± 2.3% for breast, 26.1 ± 7.3% for liver, 39.8 ± 11.8% for spleen, 96.3 ± 12.2% for renal cortex and 82.4 ± 11.6% for medulla nephrica. ICM used in enhanced CT scan resulted in increased organ doses. Our models for estimating organ dose based on CT number were established by experiment and verified in clinical use.

Optimizing the Outcomes of Percutaneous Coronary Intervention in Patients with Chronic Kidney Disease

Percutaneous coronary intervention (PCI) is one of the most common procedures performed in medicine. However, its net benefit among patients with chronic kidney disease (CKD) is less well established than in the general population. The prevalence of patients suffering from both CAD and CKD is high, and is likely to increase in the coming years. Planning the adequate management of this group of patients is crucial to improve their outcome after PCI. This starts with proper preparation before the procedure, the use of all available means to reduce contrast during the procedure, and the implementation of modern strategies such as radial access and drug-eluting stents. At the end of the procedure, personalized antithrombotic therapy for the patient's specific characteristics is advisable to account for the elevated ischemic and bleeding risk of these patients.

Patients with Different Stages of Chronic Kidney Disease Undergoing Intravenous Contrast-Enhanced Computed Tomography-The Incidence of Contrast-Associated Acute Kidney Injury

Introduction: Iodinated contrast medium (CM) is the third most common cause of acute kidney injury (AKI). However, the association is poorly known between the definitions of AKI between different stages of chronic kidney disease after intravenous CM administration. Methods: The dataset, covering a period of ~15 years (1 June 2008 to 31 March 2015), consisted of 20,018 non-dialytic adult patients who had received intravenous injections of non-ionic iso-osmolar CM, iodixanol, for enhanced computed tomography imaging. Contrast-associated AKI (CA-AKI), dialysis-required AKI, and mortality were analyzed. Results: A total of 12,271 participants were enrolled. CA-AKI increased significantly starting from stage 3A onward (p < 0.001). In summary, incidences of CA-AKI against different levels of chronic kidney disease were as follows: stage 1 (8.3%) = stage 2 (6.7%) < stage 3A (9.9%) < stage 3B (14.3%) < stage 4 (20.5%) = stage 5 (20.4%). The incidences of dialysis within 30 days were as follows: stage 1 (1%) = stage 2 (1.4%) = stage 3A (2.7%) < stage 3B (5.7%) < stage 4 (18%) < stage 5 (54.1%). The prediction of dialysis was good based on the baseline serum creatinine > 1.5 mg/dL (72.78% of sensitivity, 86.07% of specificity, 0.851 of area under curve) or baseline estimated glomerular filtration rate ≤ 38.49 mL/min/1.732 m2 (70.19% of sensitivity, 89.08% of specificity, 0.853 of area under curve). In multivariate Cox regression analysis model for CA-AKI, independent risk factors were stage 4 chronic kidney disease (p = 0.001) and shock (p = 0.001). Conclusion: Baseline serum creatinine and estimated glomerular filtration rate were good predictors for dialysis-required AKI. CA-AKI increased significantly since stage 3A chronic kidney disease. Stage 4 and 5 chronic kidney disease have the same risk for CA-AKI, but stage 5 chronic kidney disease has markedly higher risk for dialysis.

Systemic Immune-Inflammation Index May Predict the Development of Contrast-Induced Nephropathy in Patients With ST-Segment Elevation Myocardial Infarction

The aim of this study was to investigate the predictive capacity of a systemic immune-inflammation index (SII) in the detection of contrast-induced nephropathy (CIN) following ST-segment elevation myocardial infarction (STEMI). A total of 477 STEMI patients were enrolled in the study. The patients were divided into 2 groups according to CIN development. A cutoff point of 5.91 for logarithm-transformed SII was identified with 73.0% sensitivity and 57.5% specificity to predict CIN following STEMI. According to a pairwise analysis of receiver operating characteristic curve analysis, the predictive power of SII in detecting CIN following STEMI was similar to that of high-sensitivity C-reactive protein and better than the neutrophil/lymphocyte ratio or platelet/lymphocyte ratio. As a result, SII can be used as one of the independent predictors of CIN after STEMI.

Renal Safety of Repeated Intravascular Administrations of Iodinated or Gadolinium-Based Contrast Media within a Short Interval

OBJECTIVE

We aimed to investigate whether repeated intravascular administration of iodinated contrast media (ICM) or gadolinium-based contrast agents (GBCAs) within a short interval was associated with an increased risk of post-contrast acute kidney injury (PC-AKI).

MATERIALS AND METHODS

This retrospective study included 300 patients (mean age ± standard deviation, 68.5 ± 8.1 years; 131 male and 169 female) who had undergone at least one ICM-enhanced perfusion brain CT scan, had their baseline and follow-up serum creatinine levels available, and had not undergone additional contrast-enhanced examinations 72 hours before and after a time window of interest were included. The study population was divided into three groups: single-dose group and groups of patients who had received multiple contrast administrations in the time window of interest with the minimum contrast repeat interval either within 4 hours (0-4-hour group) or between 4 to 48 hours (4-48-hour group). Multivariable logistic regression analysis was conducted to evaluate the association between AKI and repeated ICM administrations. A similar supplementary analysis was performed including both ICM and GBCA.

RESULTS

When ICM was only considered ignoring GBCA, among 300 patients, 207 patients received a single dose of ICM, 58 had repeated doses within 4 hours (0-4-hour group), and 35 patients had repeated doses between 4 to 48 hours (4-48-hour group). Most patients (> 95%) had a baseline estimated glomerular filtration rate (eGFR) of ≥ 30 mL/min/1.73 m². AKI occurred in 7.2%, 13.8%, and 8.6% of patients in the single-dose, 0-4-hour, and 4-48-hour groups, respectively. In the 0-4-hour and 4-48-hour groups, additional exposure to ICM was not associated with AKI after adjusting for comorbidities and nephrotoxic drugs (all p values > 0.05).

CONCLUSION

Repeated intravascular administrations of ICM within a short interval did not increase the risk of AKI in our study patients suspected of acute stroke with a baseline eGFR of ≥ 30 mL/min/1.73 m².

Contrast-Induced Nephropathy: A Review of Mechanisms and Risks

Radiological procedures utilizing intravenous iodinated contrast agents are being widely utilized for both therapeutic and diagnostic purposes. This has resulted in an increasing incidence of procedure-related, contrast-induced nephropathy (CIN). CIN is commonly defined as a decline in kidney function occurring in a narrow time window after administration of iodinated contrast agents. Although self-limiting in most cases, CIN carries a risk of more permanent renal insufficiency, dialysis, and death. It remains a common and serious complication among at-risk patients after exposure of contrast agents. Therefore, it is important to identify patients who are at risk during early stages to implement preventative strategies to decrease the incidence of CIN. Minimizing the amount of contrast administered and providing adequate hydration are the cornerstones of an effective preventative approach. This review focuses on the basic concepts of CIN and summarizes the current understanding of its pathophysiology. In addition, it provides practical recommendations with respect to CIN prevention and management.

Acute Kidney Injury After Repeated Exposure to Contrast Material for Coronary Angiography

Objective

To assess the incidence of contrast-associated acute kidney injury (CAAKI) after repeated exposure to contrast material for computed tomography (CT) and conventional coronary angiography within short intervals.

Methods

We studied 651 patients enrolled in the CorE-64 (November 5, 2005–January 30, 2007) and CORE320 (October 21, 2009–August 17, 2011) multicenter studies. Participants with suspected obstructive coronary heart disease were referred for diagnostic cardiac catheterization and underwent coronary CT angiography for research before invasive angiography. Nonionic, low-osmolality iodinated contrast material was used for all imaging.

Results

The median age of the patients was 62 years, and 190 (29%) were women. Major risk factors for acute kidney injury were present in 277 of 651 (43%) patients. The median interval between CT imaging and invasive angiography was 3.1 days (interquartile range, 0.9-8.0 days). The median volume of contrast material was 100 mL for each test. In 16 (2.5%) of 651 patients, CAAKI developed. Of these cases, 1 occurred after the CT scan, whereas 6 were documented after invasive angiography (compared with post-CT creatinine concentration assessment). In 9 patients, CAAKI was found in comparing creatinine concentration after completion of both tests with baseline values (but not compared with post-CT imaging).

Conclusion

Acute kidney injury after repeated exposure to iodinated contrast media within a few days is uncommon even in a population of patients with highly prevalent risk factors. Withholding of clinically indicated contrast-enhanced imaging may therefore not be justified in this setting.

INASL-ISN Joint Position Statements on Management of Patients with Simultaneous Liver and Kidney Disease

Renal dysfunction is very common among patients with chronic liver disease, and concomitant liver disease can occur among patients with chronic kidney disease. The spectrum of clinical presentation and underlying etiology is wide when concomitant kidney and liver disease occur in the same patient. Management of these patients with dual onslaught is challenging and requires a team approach of hepatologists and nephrologists. No recent guidelines exist on algorithmic approach toward diagnosis and management of these challenging patients. The Indian National Association for Study of Liver (INASL) in association with Indian Society of Nephrology (ISN) endeavored to develop joint guidelines on diagnosis and management of patients who have simultaneous liver and kidney disease. For generating these guidelines, an INASL-ISN Taskforce was constituted, which had members from both the societies. The taskforce first identified contentious issues on various aspects of simultaneous liver and kidney diseases, which were allotted to individual members of the taskforce who reviewed them in detail. A round-table meeting of the Taskforce was held on 20-21 October 2018 at New Delhi to discuss, debate, and finalize the consensus statements. The evidence and recommendations in these guidelines have been graded according to the Grading of Recommendations Assessment Development and Evaluation (GRADE) system with minor modifications. The strength of recommendations (strong and weak) thus reflects the quality (grade) of underlying evidence (I, II, III). We present here the INASL-ISN Joint Position Statements on Management of Patients with Simultaneous Liver and Kidney Disease.

A Novel Antioxidant Protects Against Contrast Medium-Induced Acute Kidney Injury in Rats

Many studies proposed that oxidative stress and apoptosis are key mechanisms in the pathogenesis of contrast-induced acute kidney injury (CI-AKI). Xylose-pyrogallol conjugate (XP) is an original effective antioxidant that showed decent antioxidant and anti-apoptosis effect before. Thus the therapeutic effect and mechanism of XP in preventing CI-AKI in the short and long term were investigated in this research. Renal function and histological grade were evaluated to determine the severity of renal injury. Kidney samples were then collected for the measurement of oxidative stress markers and the detection of apoptosis. Transmission electron microscopy (TEM) and western blot of mitochondrial protein were utilized for the analysis of the mitochondrial conditions. The results demonstrated that the CI-AKI rats caused a significant decrease in renal function accompanied by a remarkable increase in Malondialdehyde (MDA), bax, caspase-3, cytochrome c (Cyt C) level, TdT-mediated dUTP nick end labeling (TUNEL) positive apoptotic cells, and damaged mitochondria, while a decline in antioxidase activities and mitochondrial superoxide dismutase 2 (SOD2) expression compared with the control rats. However, when XP (50 or 100 or 200 mg/kg/day) was given orally for consecutive 7 days before CI-AKI modeling, XP (200 mg/kg) showed a better capability to restore renal dysfunction, histopathological appearance, the level of apoptosis, mitochondrial damage, oxidative stress, and fibrosis generation without interference in computed tomographic imaging. Our study indicated that antioxidant XP played a nephroprotective role probably via antiapoptotic and antioxidant mechanisms. Besides, XP may regulate the mitochondria pathway via decreasing the ratio of bax/bcl-2, inhibiting caspase-3 expression, cytochrome c release, and superoxide dismutase 2 activity. Overall, XP as a high-efficient antioxidant may have the potentials to prevent CI-AKI.

New Fast kVp Switching Dual-Energy CT: Reduced Severity of Beam Hardening Artifacts and Improved Image Quality in Reduced-Iodine Virtual Monochromatic Imaging

RATIONALE AND OBJECTIVES

To compare degradation of the image quality due to beam hardening artifacts in reduced-iodine-dose virtual monochromatic imaging (VMI) between a new fast kVp switching dual-energy computed tomography (CT) scanner (Revolution CT) and the conventional dual-energy scanner (Discovery CT).

MATERIALS AND METHODS

First, a phantom study was performed to quantitatively evaluate beam hardening artifacts in images obtained by VMI reconstruction at different energy levels. In the second study, we performed a retrospective evaluation of the images of 28 patients who had undergone reduced-iodine (300 mg/kg) dual-energy scanning in both Revolution CT and Discovery CT. We evaluated each image quantitatively by measuring the contrast-to-noise ratio (CNR) and qualitatively by scoring the artifacts and image quality. We also calculated the modulation transfer function (MTF) and noise power spectrum (NPS) of the two scanners.

RESULTS

In the phantom study, VMI reconstruction of the CT images at 40-70 keV was associated with a significantly greater reduction in the severity of the artifacts in the Revolution CT images as compared to the Discovery CT images. In the retrospective study, there were no significant differences in the CT value of the aorta, noise, or CNR between the two scanners, but the scores for image quality were significantly higher in the Revolution CT images as compared to the Discovery CT images. The MTF of Revolution CT was higher than that of Discovery CT, reflecting the better spatial resolution.

CONCLUSION

In Revolution CT, beam hardening artifacts were reduced in reduced-iodine VMI at lower energy levels compared to Discovery CT, contributing to better image quality.

Low Ejection Fraction Predisposes to Contrast-Induced Nephropathy after the Second Step of Staged Coronary Revascularization for Acute Myocardial Infarction: A Retrospective Observational Study

Patients who develop contrast-induced nephropathy (CIN) are at an increased short-term and long-term risk of adverse cardiovascular (CV) events. Our aim was to search for patient characteristics associated with changes in serum creatinine and CIN incidence after each step of two-stage coronary revascularization in patients with acute myocardial infarction (AMI) and multivessel coronary artery disease undergoing staged coronary angioplasty during hospitalization for AMI. We retrospectively analyzed medical records of 138 patients with acute myocardial infarction without hemodynamic instability, in whom two-stage coronary angioplasty was performed during the initial hospital stay. In-hospital serum creatinine levels were recorded before the 1st intervention (at admission), within 72 h after the 1st intervention (before the 2nd intervention), and within 72 h after the 2nd intervention. The incidence of CIN was 2% after the 1st intervention (i.e., primary angioplasty) and 8% after the 2nd intervention. Patients with significant left ventricular systolic dysfunction after the 1st intervention (ejection fraction (EF) ≤35%) exhibited higher relative rises in creatinine levels after the 2nd intervention (18 ± 29% vs. 2 ± 16% for EF ≤35% and >35%, respectively, p = 0.03), while respective creatinine changes after the 1st revascularization procedure were comparable (−1 ± 14% vs. 2 ± 13%, p = 0.4). CIN after the 2nd intervention was over five-fold more frequent in subjects with low EF (28% vs. 5%, p = 0.007). The association between low EF and CIN incidence or relative creatinine changes after the 2nd intervention was maintained upon adjustment for baseline renal function, major CV risk factors, and the use of renin-angiotensin axis antagonists prior to admission. In conclusion, low EF predisposes to CIN after second contrast exposure in patients undergoing two-stage coronary angioplasty during the initial hospitalization for AMI. Our findings suggest a need of extended preventive measures against CIN or even postponement of second coronary intervention in patients with significant left ventricular dysfunction scheduled for the second step of staged angioplasty.

Assessment of Split Renal Function Using a Combination of Contrast-Enhanced CT and Serum Creatinine Values for Glomerular Filtration Rate Estimation

OBJECTIVE. The objective of our study was to develop a novel method to estimate single-kidney glomerular filtration rate (GFR) using a combination of contrast-enhanced CT and serum creatinine (SCr) values and to validate the resulting estimated glomerular filtration rates (eGFRs) by comparing them with the single-kidney Gates GFR, which is based on renal dynamic imaging. MATERIALS AND METHODS. Sixty-two patients with asymmetric renal disease who underwent unenhanced and triphasic contrast-enhanced CT of the kidneys, ^99mTc-diethylenetriamine pentaacetic acid renal dynamic imaging, and SCr testing within 1 week were retrospectively included. The eGFR was split into single-kidney GFRs of the left and right kidneys by a proportionality factor derived from the products of renal volume and CT number increments of the multiphasic CT images, which produced unenhanced phase (yielded by the renal volume proportional factor alone), arterial phase, venous phase, and nephrographic phase CT split eGFRs. The four CT split eGFRs were compared with the Gates GFR using the paired-sample t test, Pearson correlation analysis, and Bland-Altman analysis. RESULTS. Correlation coefficients and 95% CIs between the four CT split eGFRs and Gates GFR were as follows: unenhanced phase, 0.729 (95% CI, 0.626-0.805); arterial phase, 0.781 (95% CI, 0.685-0.849); venous phase, 0.788 (95% CI, 0.690-0.839); and nephrographic phase, 0.842 (95% CI, 0.758-0.902) (all, p < 0.001). The paired differences between the CT split eGFRs and Gates GFR were as follows: unenhanced phase, 2.04 ± 10.85 (95% CI, 0.01-4.07) mL/min/1.73 m²; arterial phase, 2.04 ± 10.56 (95% CI, 0.06-4.02) mL/min/1.73 m²; venous phase, 2.04 ± 10.04 (95% CI, 0.16-3.92) mL/min/1.73 m²; and nephrographic phase, 2.04 ± 8.92 (95% CI, 0.37-3.71) mL/min/1.73 m². These results suggest a maximum deviation from the Gates GFR of ± 44.9% for the unenhanced phase eGFR, ± 43.7% for the arterial phase eGFR, ± 41.6% for the venous phase eGFR, and ± 36.9% for nephrographic phase eGFR. CONCLUSION. Split renal function can be estimated using a combination of contrast-enhanced CT and SCr values to calculate eGFR. The CT images of the nephrographic phase may be the optimal choice to use in this proposed method.

Hydration Strategies for Preventing Contrast-Induced Acute Kidney Injury: A Systematic Review and Bayesian Network Meta-Analysis

Aims

Many previous studies have examined the effect of different hydration strategies on prevention of contrast-induced acute kidney injury (CI-AKI), but the optimal strategy is unknown. We performed a network meta-analysis (NWM) of these previous studies to identify the optimal strategy.

Methods and Results

Web of Science, PubMed, OVID Medline, and Cochrane Library were searched from their inception dates to September 30, 2018. Randomized controlled trials (RCTs) were selected based on strict inclusion criteria, and a Bayesian NWM was performed using WinBUGS V.1.4.3. We finally analyzed 60 eligible RCTs, which examined 21,293 patients and 2232 CI-AKI events. Compared to intravenous 0.9% sodium chloride (reference), intravenous sodium bicarbonate (OR [95% CI]: 0.74 [0.57, 0.93]), hemodynamic guided hydration (0.41 [0.18, 0.93]), and RenalGuard guided hydration (0.32 [0.14, 0.70]) significantly reduced the occurrence of CI-AKI. Oral hydration and intravenous 0.9% sodium chloride were each noninferior to no hydration in preventing CI-AKI. Intravenous 0.9% sodium chloride, sodium bicarbonate, and hemodynamic guided hydration were each noninferior to oral hydration in preventing CI-AKI. Based on surface under the cumulative ranking curve values, the RenalGuard system was best (0.974) and hemodynamic guided hydration was second best (0.849).

Conclusion

There was substantial evidence to support the use of RenalGuard or hemodynamic guided hydration for preventing CI-AKI in high-risk patients, especially those with chronic kidney disease or cardiac dysfunction.

Biomarkers for Diagnosis and Prediction of Outcomes in Contrast-Induced Nephropathy

Background

Serum creatinine is suboptimal as a biomarker in the early diagnosis of contrast-induced nephropathy (CIN). In this study, we investigated a panel of novel biomarkers in the early diagnosis of CIN and in assessing patient outcomes.

Methods

This single-centre, nested, prospective case-controlled study included 30 patients with CIN and 60 matched controls. Serum and urine samples were collected before contrast administration and at 24 hours, 48 hours, and ≥5 days after contrast administration. Concentrations of NGAL, cystatin C, β₂M, IL18, IL10, KIM1, and TNFα were determined using Luminex and ELISA assays. Outcomes were biomarker diagnostic discrimination performance for CIN and mortality after generation of area under receiver operating characteristic curves (AUROCs).

Results

Median serum levels for 24 h cystatin C (p < 0.01) and 48 h β₂M levels (p < 0.001) and baseline urine NGAL (p=0.02) were higher in CIN patients compared to controls with AUROCs of 0.75, 0.78, and 0.74, respectively, for the early diagnosis of CIN. Serum β₂M levels were higher in CIN patients at all time points. Elevated baseline serum concentrations of IL18 (p < 0.001), β₂M (p=0.04), TNFα (p < 0.001), and baseline urine KIM (p=0.01) and 24 h urine NGAL (p=0.02) were significantly associated with mortality. Baseline serum concentrations of IL18, β₂M, and TNFα showed the best discrimination performance for mortality with AUROCs, all >0.80. Baseline NGAL was superior for excluding patients at risk for CIN, with positive and negative predictive ranges of 0.50–0.55 and 0.81–0.88, respectively. Cystatin C (p=0.003) and β₂M (p=0.03) at 24 h independently predicted CIN risk. β₂M predicted increased mortality of 40% at baseline and 50% at 24 hours.

Conclusion

Serum cystatin C at 24 h was the best biomarker for CIN diagnosis, while baseline levels of serum IL18, β₂M, and TNFα were best for predicting prognosis.

Iodine load reduction in dual-energy spectral CT portal venography with low energy images combined with adaptive statistical iterative reconstruction

OBJECTIVE

To study the application of using low energy images combined with adaptive statistical iterative reconstruction (ASiR) in dual-energy spectral CT portal venography (CTPV) to reduce iodine load.

METHODS

41 patients for CTPV were prospectively and randomly divided into two groups. Group A ( n = 21) used conventional 120 kVp scanning protocol with contrast dose at 0.6 gI/kg while group B ( n = 20) used dual-energy spectral imaging with reduced contrast dose at 0.3 gI/kg. The 120 kVp images in Group A and 50 keV images in Group B were reconstructed with 40% ASiR. The contrast-to-noise ratio of portal vein was calculated. The image quality and the numbers of intrahepatic portal vein branches were evaluated by two experienced radiologists using a 5-point scoring system.

RESULTS

Group B reduced iodine load by 52% compared to Group A (17.21 ± 3.30 gI vs 35.80 ± 6.18 gI, p < 0.001). All images in both groups were acceptable for diagnosis. CT values and standard deviations in portal veins of Group B were higher than Group A (all p < 0.05); There were no statistical differences in contrast-to-noise ratio, image quality score and the number of observed portal vein branches between the two groups (all p > 0.05), and the two observers had excellent agreement in image quality assessment (all κ > 0.75).

CONCLUSION

The use of 50 keV images in dual-energy spectral CTPV with ASiR reduces total iodine load by 52% while maintaining good image quality.

ADVANCES IN KNOWLEDGE

Spectral CT images combined with ASiR can be used in low contrast dose CTPV portal venography to maintain image quality and reduce contrast dose.

Is it possible to prevent contrast-induced nephropathy with dexpanthenol?

PURPOSE

Contrast-induced nephropathy (CIN) is one of the side effects of diagnostic procedures. Oxidative stress plays an important role in CIN's pathophysiology. Dexpanthenol (Dexp) is a substance with antioxidant efficacy. We investigated the likely protective effects of dexpanthenol for CIN.

METHODS

Twenty-four Sprague-Dawley rats were divided randomly into four groups of 6 rats; control (group 1), Dexp (group 2), CIN (group 3) and Dexp + CIN (group 4). All rats were restricted of water moderately to facilitate of nephrotoxicity. Dexp was administered into the intraperitoneally at a dose of 500 mg/kg for 5 days in groups 2 and 4. The same amount of saline was applied via intraperitoneally to group 1 and 3. In CIN and Dexp + CIN groups, L-NAME (10 mg/kg), tenoxicam (0.5 mg/kg) and sodium amidotrizoate (10 ml/kg) were administered on the 4th day via the tail vein for CIN. All rats were euthanized on the 6th day and samples for biochemical and pathological evaluations were collected.

RESULTS

When the Dexp + CIN group and the CIN group were compared, it was found to be provide a significant decline at the level of acute tubular injury and necrosis in kidney biopsies by dexp. Furthermore Dexp significantly reduced the serum cystatin C (Cys-C) levels, not serum creatinine. There was no statistically significant difference between the groups in total oxidant and antioxidant levels.

CONCLUSIONS

Dexpanthenol did not have significant effect on oxidative stress of acute kidney injury on this rat model. However, it has ameliorated serum Cys-C levels and histopathological findings of CIN.

Non-coding RNA-Associated ceRNA Networks in a New Contrast-Induced Acute Kidney Injury Rat Model

Contrast-induced acute kidney injury (CI-AKI) is a severe complication of intravascular applied radial contrast media, and recent progress in interventional therapy and angiography has revived interest in explaining detailed mechanisms and developing effective treatment. Recent studies have indicated a potential link between CI-AKI and microRNA (miRNA). However, the potential non-coding RNA-associated-competing endogenous RNA (ceRNA) pairs involved in CI-AKI still remain unclear. In this study, we systematically explored the circRNA or lncRNA-associated-ceRNA mechanism in a new rat model of CI-AKI through deep RNA sequencing. The results revealed that the expression of 38 circRNAs, 12 lncRNAs, 13 miRNAs and 127 mRNAs were significantly dysregulated. We performed Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses for mRNAs with significantly different expression and then constructed comprehensive circRNA or lncRNA-associated ceRNA networks in kidney of CI-AKI rats. Thereafter, two constructed ceRNA regulatory pathways in this CI-AKI rat model—novel_circ_0004153/rno-miR-144-3p/Gpnmb or Naglu and LNC_000343/rno-miR-1956-5p/KCP—were validated by real-time qPCR. This study is the first one to provide a systematic dissection of non-coding RNA-associated ceRNA profiling in kidney of CI-AKI rats. The selected non-coding RNA-associated ceRNA networks provide new insight for the underlying mechanism and may profoundly affect the diagnosis and therapy of CI-AKI.

Contrast Induced Acute Kidney Injury and Direct Cytotoxicity of Iodinated Radiocontrast Media on Renal Proximal Tubule Cells

The administration of intravenous iodinated radiocontrast media (RCM) to visualize internal structures during diagnostic procedures has increased exponentially since their first use in 1928. A serious side effect of RCM exposure is contrast-induced acute kidney injury (CI-AKI), which is defined as an abrupt and prolonged decline in renal function occurring 48-72 hours after injection. Multiple attempts have been made to decrease the toxicity of RCM by altering ionic strength and osmolarity, yet there is little evidence to substantiate that a specific RCM is superior in avoiding CI-AKI. RCM-associated kidney dysfunction is largely attributed to alterations in renal hemodynamics, specifically renal vasoconstriction; however, numerous studies indicate direct cytotoxicity as a source of epithelial damage. Exposure of in vitro renal proximal tubule cells to RCM has been shown to affect proximal tubule epithelium in the following manner: 1) changes to cellular morphology in the form of vacuolization; 2) increased production of reactive oxygen species, resulting in oxidative stress; 3) mitochondrial dysfunction, resulting in decreased efficiency of the electron transport chain and ATP production; 4) perturbation of the protein folding capacity of the endoplasmic reticulum (ER) (activating the unfolded protein response and inducing ER stress); and 5) decreased activity of cell survival kinases. The present review focuses on the direct cytotoxicity of RCM on proximal tubule cells in the absence of in vivo complications, such as alterations in renal hemodynamics or cytokine influence.

Evaluation of Ameliorative Potential of Vitamins E and C on DNA Double Strand Break (DSB) in Patients Undergoing Computed Tomography (CT): A Clinical Study

Computed tomography (CT) is one of the most important diagnostic X-ray procedures which plays an important role in increasing the patient dose values. The purpose of this clinical study was to evaluate the efficacy of vitamins E and C in lowering down the level of DNA double strand break (DSB) caused by CT scan. Sixty patients for abdomen/pelvic enhanced CT scan were randomly assigned to placebo (control), vitamin C, and vitamin E groups. The patient blood samples were taken before and immediately after the CT scan. Counting the number of DSB was performed using γ-H2AX method as a sensitive biomarker. Immediately after the CT scan, the mean number of DSBs/cell increased in all three groups of control (131%, P<0.001), vitamin C (103%, P <0.001), and vitamin E (66%, P<0.001) compared to their mean before the CT scan. Furthermore, the results showed that vitamin E decreased the mean number of DSBs/cell by 22% in comparison with the control group (P =0.023), whereas vitamin C had no significant effect on reducing the DSB (<3%, P =0.741). It is concluded that the administration of vitamin E one hour before the CT scan, significantly decreases DSB levels.

Recent surgical treatments for urinary stone disease in a Korean population: National population-based study

OBJECTIVES

To provide surgical treatment trends for urinary stone disease in Korea.

METHODS

We analyzed medical service claim data of surgical treatments to urinary stone disease submitted by medical service providers from the Health Insurance Review and Assessment Service from 2009 to 2016.

RESULTS

There was a significantly increasing trend among outpatients and inpatients for urinary stone disease from 2009 to 2016 (R²  = 0.643, P = 0.017; R²  = 0.575, P = 0.029). The number of shock wave lithotripsy for treating urinary stone disease increased by 16% from 89 553 in 2009 to 104 013 in 2016 (R²  = 0.684). The number of ureteroscopic lithotripsy increased by 97% from 6106 in 2009 to 12 057 in 2016 (R²  = 0.99). The number of flexible ureteroscopic lithotripsy increased by 16-fold from 219 in 2009 to 3712 in 2016 (R²  = 0.756). The number of percutaneous nephrolithotomy increased by 99.7% from 919 in 2009 to 1835 in 2016 (R²  = 0.987). The use of non-contrast and contrast-enhanced computed tomography in the diagnostic codes for urinary stone disease increased by 394.8% and 263.3% from 2009 to 2016, respectively (R²  = 0.83; R²  = 0.967). Conversely, the use of intravenous pyelography decreased 26.2% over the same period (R²  = 0.945).

CONCLUSIONS

Outpatient and inpatient procedures for urinary stone disease have increased over the past 8 years in Korea. Shock wave lithotripsy is the most widely used treatment modality for urinary stone disease, and endoscopic surgical procedures are rapidly being implemented. There has been a steep increase in the use of computed tomography, whereas conventional intravenous pyelography is declining.

Probucol Protects Against Contrast-Induced Acute Kidney Injury via the Extracellular Signal-Regulated Kinases 1 and 2 (ERK1/2)/JNK-Caspase 3 Pathway in Diabetic Rats

Background

Contrast-induced acute kidney injury is an important clinical problem, yet its pathogenic mechanisms are incompletely understood. In this study we explored the potential beneficial effects of probucol as treatment of contrast-induced acute kidney injury in diabetic rats.

Material/Methods

Rats were divided into 3 groups: i) diabetic control, ii) diabetic with contrast, and iii) probucol treatment groups. Probucol was administered by gavage and the contrast diatrizoate (60%) was injected via femoral vein. After 24 h, the rats were sacrificed and samples were taken to measure biochemical indicators. Pathological damage of renal tubules was evaluated by HE staining. Expression of Bcl-2, Bax, p-ERKs, and p-JNK proteins in the kidneys was examined by Western blotting, whereas expression level of caspase-3 in kidneys was detected by immunohistochemistry.

Results

Compared to the probucol treatment group, the diabetes with contrast group showed higher serum creatinine and lower creatinine clearance. The pathological changes of kidneys in the probucol treatment group were improved compared with the contrast group. Moreover, Western blot analyses revealed that use of contrast agent led to lower p-ERK1/2, higher p-JNK, lower Bcl-2, and higher Bax levels, which were reversed by probucol. Finally, immunohistochemical findings revealed higher caspase-3 after contrast use, which was partially reversed by probucol.

Conclusions

Probucol exerts protective effects on contrast-induced acute kidney injury in diabetic rats by inhibition of renal cell apoptosis. This is achieved by reducing mitochondrial caspase-3 expression through increasing and decreasing the expression of the upstream mediators p-ERK1/2 and p-JNK, respectively.

The influence of the iodinate contrast medium during CT: Single center experience - Development of two competitive in-house methods for automated quantification of DDSB

DNA damage induced by ionizing radiation may ultimately lead to cell death or initiate cancer cells development. Today it is difficult to estimate what the actual damage to the human body will be, given the fact that today in the world the number of diagnostic procedures using radiation and iodine contrast media is increasing, and the existence of a number of factors that can affect the radiation dose in vivo. At the same time, development of new methods is required, which can determine in a much shorter time what will be the effect of diagnostic radiation on the DNA molecule. For these purposes we develop two competitive inhouse methods for automated quantification of DNA double strand brakes (DDSB) in peripheral blood lymphocytes: immunofluorescence determining of γH2AX with stained microscopic slides and determining the occurrence of DDSB with the flow cytometry. Our initial results shown that computed tomography (CT) can cause damage in the DNA molecule in the form of DDSB, the existence of linear dependence with the increase in low and high range of CTDI and the number of γH2AX, and that iodine contrast media can increase the occurrence of DNA double strand brakes. Keywords: CT examinations, ICM, immunofluorescence, flow cytometry, DDSB

[Management of renal failure in old patients undergoing percutaneous cardiac interventions]

The elderly benefit from the advances of the interventional cardiology, especially for coronary artery disease and aortic valve stenosis. The prevalence of comorbidities is high in old population, but the benefit-risk balance remains often positive. Chronic kidney disease is frequent and amplifies the risks of contrast-induced nephropathy and acute kidney injury with an impact on clinical course and outcomes, and additional costs. Preventive strategies recognized as efficient to limit renal adverse events must be applied. Future approach may involve research in vulnerable old patients undergoing cardiac interventions.

Prophylactic Intravenous Hydration to Protect Renal Function From Intravascular Iodinated Contrast Material (AMACING): Long-term Results of a Prospective, Randomised, Controlled Trial

BACKGROUND

The aim of A MAastricht Contrast-Induced Nephropathy Guideline (AMACING) trial was to evaluate non-inferiority of no prophylaxis compared to guideline-recommended prophylaxis in preventing contrast induced nephropathy (CIN), and to explore the effect on long-term post-contrast adverse outcomes. The current paper presents the long-term results.

METHODS

AMACING is a single-centre, randomised, parallel-group, open-label, phase 3, non-inferiority trial in patients with estimated glomerular filtration rate [eGFR] 30-59 mL/min/1.73 m2 combined with risk factors, undergoing elective procedures requiring intravenous or intra-arterial iodinated contrast material. Exclusion criteria were eGFR < 30 mL/min/1.73 m2, dialysis, no referral for prophylaxis. The outcomes dialysis, mortality, and change in renal function at 1 year post-contrast were secondary outcomes of the trial. Subgroup analyses were performed based on pre-defined stratification risk factors. AMACING is registered with ClinicalTrials.gov: NCT02106234.

FINDINGS

From 28,803 referrals, 1120 at-risk patients were identified. 660 consecutive patients agreed to participate and were randomly assigned (1:1) to no prophylaxis (n = 332) or standard prophylactic intravenous hydration (n = 328). Dialysis and mortality data were available for all patients. At 365 days post-contrast dialysis was recorded in two no prophylaxis (2/332, 0.60%), and two prophylaxis patients (2/328, 0.61%; p = 0.9909); mortality was recorded for 36/332 (10.84%) no prophylaxis, and 32/328 (9.76%) prophylaxis patients (p = 0.6490). The hazard ratio was 1.118 (no prophylaxis vs prophylaxis) for one-year risk of death (95% CI: 0.695 to 1.801, p = 0.6449). The differences in long-term changes in serum creatinine were small between groups, and gave no indication of a disadvantage for the no-prophylaxis group.

INTERPRETATION

Assuming optimal contrast administration, not giving prophylaxis to elective patients with eGFR 30-59 mL/min/1.73 m2 is safe, even in the long-term.

FUNDING

Stichting de Weijerhorst.

Comparison of full-iodine conventional CT and half-iodine virtual monochromatic imaging: advantages and disadvantages

PURPOSE

To compare image quality of abdominal arteries between full-iodine-dose conventional CT and half-iodine-dose virtual monochromatic imaging (VMI).

MATERIALS AND METHODS

We retrospectively evaluated images of 21 patients (10 men, 11 women; mean age, 73.9 years) who underwent both full-iodine (600 mg/kg) conventional CT and half-iodine (300 mg/kg) VMI. For each patient, we measured and compared CT attenuation and the contrast-to-noise ratio (CNR) of the aorta, celiac artery, and superior mesenteric artery (SMA). We also compared CT dose index (CTDI). Two board-certified diagnostic radiologists evaluated visualisation of the main trunks and branches of the celiac artery and SMA in maximum-intensity-projection images. We evaluated spatial resolution of the two scans using an acrylic phantom.

RESULTS

The two scans demonstrated no significant difference in CT attenuation of the aorta, celiac artery, and SMA, but CNRs of the aorta and celiac artery were significantly higher in VMI (p = 0.011 and 0.030, respectively). CTDI was significantly higher in VMI (p = 0.024). There was no significant difference in visualisation of the main trunk of the celiac artery and SMA, but visualisation of the gastroduodenal artery, pancreatic arcade, branch of the SMA, marginal arteries, and vasa recta was significantly better in the conventional scan (p < 0.001). The calculated modular transfer function (MTF) suggested decreased spatial resolution of the half-iodine VMI.

CONCLUSION

Large-vessel depiction and CNRs were comparable between full-iodine conventional CT and half-iodine VMI images, but VMI did not permit clear visualisation of small arteries and required a larger radiation dose.

KEY POINTS

・Reducing the dose of iodine contrast medium is essential for chronic kidney disease patients to prevent contrast-induced nephropathy. ・In virtual monochromatic images at low keV, contrast of relatively large vessels is maintained even with reduced iodine load, but visibility of small vessels is impaired with decreased spatial resolution. ・We should be aware about the advantages and disadvantages associated with virtual monochromatic imaging with reduced iodine dose.

Evaluation of nephroprotection of silymarin on contrast-induced nephropathy in liver cirrhosis patients: A population-based cohort study

Recent findings from an animal experiment suggest a modest association between silymarin and decreased risk of contrast-induced nephropathy. However, the relationship between silymarin and contrast-induced nephropathy in patients with liver cirrhosis remains unclear.From 1997 to 2007, we identified 3019 patients with liver cirrhosis who were administered silymarin and matched them with 3019 patients with liver cirrhosis who were not administered silymarin. Each patient was followed up for a minimum of 4 years. After adjusting for age, gender, hepatitis B, hepatitis C, alcoholic hepatitis, and Charlson comorbidity index, we considered death occurrence and used the Fine and Gray regression models to calculate subdistribution hazard ratios (sHRs) for contrast-induced nephropathy. Sensitivity analyses were also performed using the same model on the subgroups classified by comorbidity.Using the Fine and Gray regression models and with death as the competing risk, we observed that sHR for contrast-induced nephropathy was 0.94-fold higher in the silymarin cohort than in the nonsilymarin cohort (95% confidence interval = 0.61-1.47, P = .791). On the basis of sensitivity analyses results classified by comorbidity, a nonsignificant decrease in risk of contrast-induced nephropathy was found.Silymarin shows no nephron-protective positive effects on contrast-induced nephropathy. Silymarin did not play a nephron-protective role according to Longitudinal Health Insurance Database of Taiwan. Clinical trials are necessary to further assess the nephron-protective effects of silymarin of contrast-induced nephropathy.

Chromosomal Abnormalities in Human Lymphocytes after Computed Tomography Scan Procedure

The incidence of chromosomal abnormalities and cancer risk correlates well with the radiation dose after exposure to moderate- to high-dose ionizing radiation. However, the biological effects and health risks at less than 100 mGy, e.g., from computed tomography (CT) have not been ascertained. To investigate the biological effects of low-dose exposure from a CT procedure, we examined chromosomal aberrations, dicentric and ring chromosomes (dic+ring), in peripheral blood lymphocytes (PBLs), using FISH assays with telomere and centromere PNA probes. In 60 non-cancer patients exposed to CT scans, the numbers of dicentric and ring chromosomes were significantly increased with individual variation. The individual variations in the increment of dicentric and ring chromosomes after CT procedures were confirmed using PNA-FISH analysis of PBLs from 15 healthy volunteers after in vitro low-dose exposure using a ¹³⁷Cs radiation device. These findings strongly suggest that appropriate medical use of low-dose radiation should consider individual differences in radiation sensitivity.

Using kidney size for early detection of contrast-induced nephropathy in the emergency department setting

AIM

We aimed to examine the relationship between kidney size and contrast-induced nephropathy (CIN) in patients who underwent contrast-enhanced computed tomography (CT) in the emergency department.

METHODS

This single-center retrospective observational study was undertaken to evaluate risk factors for CIN at Okayama Saiseikai General Hospital (Okayama, Japan) from January 2014 through to December 2016. Contrast-induced nephropathy was defined as an absolute increase in serum creatinine level of ≥0.5 mg/dL or ≥25% over the baseline value within 72 h after contrast-enhanced CT. Independent risk factors for CIN were determined by multiple logistic regression analysis. The thickness of the kidney was evaluated as a predictor of CIN using the area under the receiver operating characteristic curve. We also analyzed CIN as an outcome using the Kaplan-Meier method.

RESULTS

The incidence of CIN was 26/262 (9.9%). In the multivariate analysis, CIN was associated with renal thickness (odds ratio = 0.65; 95% confidence interval, 0.53-0.81). No patient underwent renal replacement therapy.

CONCLUSION

Renal thickness could be used as a reliable, simple, and easily obtainable marker for identifying CIN in patients undergoing contrast-enhanced CT in the emergency department.

Nonfluoroscopic catheter ablation of paroxysmal atrial fibrillation

AIMS

Radiofrequency catheter ablation of atrial fibrillation (AF) is one of the most complex ablation procedures. Both patients and operators are exposed to scattered radiation. This study evaluated the safety and efficacy of intracardiac echo (ICE)-guided pulmonary vein isolation (PVI) without fluoroscopy.

METHODS

We retrospectively analyzed the data of 481 consecutive patients with paroxysmal AF undergoing radiofrequency PVI with the CARTO 3 system (Biosense Webster, Diamond Bar, CA, USA). ICE-guided PVI without fluoroscopy and without CT/MRI integration (Nonfluoro group) was performed for 245 patients, and conventional fluoroscopy-guided PVI (Fluoro group) was performed for 236 patients. The primary safety endpoint was the incidence of major adverse events. The primary efficacy endpoint was freedom from AF during follow-up. Secondary endpoints included procedure duration, fluoroscopy duration, and acute PVI rate.

RESULTS

Mean procedure times between groups were similar (108.8 ± 18.2 minutes in the Non-fluoro group vs 113.6 ± 26.8 minutes in the Fluoro group; P  =  not significant [NS]). Acute PVI was achieved in all patients, with mean radiofrequency application times of 43.4 ± 7.5 and 44.4 ± 10.7 minutes for the Nonfluoro and Fluoro groups, respectively (P  =  NS). The incidence of cardiac tamponade was 1.2% (3/245 patients) in the Nonfluoro group and 0.8% (2/236 patients) in the Fluoro group (P  =  NS). During 15.2 ± 4.1 months of follow-up, after a single procedure, AF recurrence was documented in 65 of 245 (26.5%) patients and 61 of 236 (25.8%) patients in the Nonfluoro and Fluoro groups, respectively (P  =  NS).

CONCLUSIONS

Nonfluoroscopic ICE-guided catheter ablation of AF without prior cardiac image integration or angiography is feasible and safe. PVI without fluoroscopy did not affect procedure duration or long-term efficacy.

Prevention of contrast-induced nephropathy by limb ischemic preconditioning: underlying mechanisms and clinical effects

Contrast-induced nephropathy (CIN) is an important complication following diagnostic radiographic imaging and interventional therapy. It results from administration of intravascular iodinated contrast media (CM) and is currently the third most common cause of hospital-acquired acute kidney injury. CIN is associated with increased morbidity, prolonged hospitalization, and higher mortality. Although the importance of CIN is widely appreciated, and its occurrence can be mitigated by the use of pre- and posthydration protocols and low osmolar instead of high osmolar iodine-containing CM, specific prophylactic therapy is lacking. Remote ischemic preconditioning (RIPC), induced through short cycles of ischemia-reperfusion applied to the limb, is an intriguing new strategy that has been shown to reduce myocardial infarction size in patients undergoing emergency percutaneous coronary intervention. Furthermore, multiple proof-of-principle clinical studies have suggested benefit in several other ischemia-reperfusion syndromes, including stroke. Perhaps somewhat surprisingly, RIPC also is emerging as a promising strategy for CIN prevention. In this review, we discuss current clinical and experimental developments regarding the biology of CIN, concentrating on the pathophysiology of CIN, and cellular and molecular mechanisms by which limb ischemic preconditioning may confer renal protection in clinical and experimental models of CIN.

Incidence of Breakthrough Reaction in Patients with Prior Acute Allergic-Like Reactions to Iodinated Contrast Media according to the Administration Route

Objective

This study assessed the risk of acute allergic-like reactions (AARs) after extravascular administration of iodinated contrast media (ICM) in at-risk patients compared with that after intravascular ICM administration.

Materials and Methods

From July 2012 to January 2016, 264 patients with a history of moderate or severe reactions to ICM, with re-exposure to ICM intravascularly or extravascularly were included. The incidence of recurrent AARs after ICM re-exposure were assessed according to the administration routes by reviewing electronic medical records and comparison between the two routes.

Results

Among 264 patients, 244 patients had been subsequently exposed to ICM intravascularly, 7 patients via an extravascular route and 13 patients with dual re-exposure. Of 257 patients with intravascular ICM re-exposure, 87 (33.9%) had mild to severe recurrent AARs and 143 (19.5%) cases of recurrent AARs occurred among 733 cases of intravascular ICM re-exposure on a case-by-case basis. However, there was no case of recurrent ARR after extravascular administration of ICM in 20 patients (45 cases) with ICM administrated extravascularly.

Conclusion

For high-risk patients with a history of moderate or severe reactions to ICM, AARs upon extravascular administration of ICM are significantly infrequent compared with intravascular ICM administration.

CKD-EPI versus Cockcroft-Gault formula for predicting contrast-induced nephropathy following percutaneous coronary intervention in patients without significant renal impairment

INTRODUCTION

Individuals with glomerular filtration rate (GFR) ≥60 ml/min/1.73 m² estimated by the Cockcroft-Gault formula (CG) who undergo percutaneous coronary intervention (PCI) frequently develop contrast-induced nephropathy (CIN). This study aimed to assess whether individuals with significant renal impairment assessed by the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula, but not by CG, more often develop CIN following PCI than those without renal impairment by either formula.

METHODS

In this cross-sectional study analyzing patients with baseline CG GFR ≥60 ml/min/1.73 m² before PCI, subjects were divided into two groups according to CIN occurrence. Baseline CKD-EPI GFR was calculated for all patients.

RESULTS

We analyzed 140 patients. Baseline GFR was 87.5±21.3 and 77.1±15.0 ml/min/1.73 m² for CG and CKD-EPI, respectively. CIN occurred in 84.6% of individuals with baseline CKD-EPI GFR <60 ml/min/1.73 m² vs. 51.1% of those without. Males and those with higher body mass index were more likely to present baseline CKD-EPI GFR <60 ml/min/1.73 m² (p=0.021). Non-ionic contrast agent use and baseline CKD-EPI GFR ≥60 ml/min/1.73 m² were protective factors against CIN. Greater amounts of contrast agent and acute coronary syndrome were associated with higher CIN risk. In subjects with serum creatinine <1.0 mg/dl, GFR was more likely to be overestimated by CG, but not by CKD-EPI (sensitivity 100.0%; specificity 52.0%).

CONCLUSION

In patients undergoing PCI without renal dysfunction by CG, a finding of CKD-EPI GFR <60 ml/ min/1.73 m² was associated with a higher probability of CIN, especially among men and those with higher body mass index.

Active targeted dual-modal CT/MR imaging of VX2 tumors using PEGylated BaGdF5 nanoparticles conjugated with RGD

RGD-PEG-BaGdF₅ NPs can be used as CT/MR dual-modality contrast agents of solid tumors via the RGD-mediated tumor vasculature targeting strategy.

Effect of Melatonin Administration on Prevention of Contrast- Induced Nephropathy following Coronary Angiography

Introduction. Contrast-induced-nephropathy (CIN) is a common complication during angiography that may lead to long-term complications. This study was conducted to investigate the effect of melatonin administration on prevention of CIN in patients who underwent coronary angiography with intra-arterial contrast agents. Method. This is single-blind randomized clinical trial that was performed over 100 patients with indication for coronary angiography. Patients are randomly assigned to two equal groups. All patients in the 12 hours before and 12 hours after the procedure, were received adequate intravenous hydration with normal saline and for the intervention group in addition to hydration, the day before angiography and immediately after angiography 3 mg melatonin was administered. For all patients, serum level of creatinine (Cr), blood urea nitrogen (BUN) and glomerular filtration rate (GFR) before and 48 hours after the procedure were measured. Data were analyzed using SPSS 18 software. Results. Totally 100 participants with the mean age of 64.0±8.2 years were enrolled (63% male). There was no significant difference between intervention and control groups in baseline and demographic characteristics (P> 0.05). Although the mean serum Cr and BUN level increased in both groups, but the mean Cr, BUN and GFR before and after coronary angiography was not statistically significant. Based on the definition of CIN in the current study, 3(6%) patients from intervention group and 2(4%) patients from control group were affected by CIN (P = 0.243). Conclusion. It is likely that, melatonin administration has no significant effect on prevention of CIN following coronary angiography.

Platelet-to-lymphocyte ratio predicts contrast-induced acute kidney injury in diabetic patients with ST-elevation myocardial infarction

AIM

There has been a rise in contrast-induced acute kidney injury (CI-AKI). We examined the role of platelet-to-lymphocyte ratio (PLR) in predicting CI-AKI episodes in patients with myocardial infarction (MI) and diabetes.

METHODS

A total of 719 patients with diabetes and MI were enrolled. Study population was divided into: group 1 (n = 615) without CI-AKI and group 2 (n = 104) with CI-AKI.

RESULTS

Patients with CI-AKI had higher in-hospital mortality and a longer in-hospital stay. Median PLR was higher in patients with CI-AKI. Receiver operating characteristic analysis indicated PLR to be a good predictive tool in assessing the risk of CI-AKI. PLR was an independent predictor of CI-AKI (OR: 1.22; p < 0.0001).

CONCLUSION

These results suggest potential role for PLR as a biomarker of CI-AKI among diabetic patients with MI who undergo percutaneous coronary intervention.