Early creatinine shifts predict contrast-induced nephropathy and persistent renal damage after angiography

Contrast-Induced Nephropathy in Interventional Cardiology: Incidence, Risk Factors, and Identification of High-Risk Patients

AIM

This study aimed to study contrast-induced nephropathy (CIN) or more recent nomenclature contrast-associated acute kidney injury (CI-AKI) in patients undergoing percutaneous coronary procedures, evaluating CIN incidence, risk factors (RFs), and high-risk patients with CIN.  Methods: This is a prospective, observational, unicentric trial of patients who underwent coronary angiography and/or percutaneous coronary intervention (PCI) in the University Hospital Center (UHC) "Mother Teresa" in Tirana, Albania, during 2016-2018. CIN was defined as an increase of 25% and/or by 0.5 mg/dL of serum creatinine (SCr) and high-risk patients with CIN as an increase by 50% and/or by 2 mg/dL and/or need for dialysis compared to the basal pre-procedural values. We evaluated RFs for CIN: preexisting renal lesion (PRL), heart failure (HF), age, diabetes mellitus (DM), anemia, and contrast quantity.  Results: The incidence of CIN resulted in 14.4%. HF, PRL, and age ≥65 years resulted in independent RFs for CIN, whereas anemia, DM, and contrast quantity >100 mL did not. PRL proved to be the most important RF for CIN, whereas HF was the only independent RF for high-risk CIN patients.

CONCLUSIONS

The incidence of CIN coincides with the results in the literature. PRL, HF, and age ≥65 years resulted in independent RFs for CIN; more and larger trials are needed to evaluate DM, anemia, and contrast quantity related to their impact on CIN. High-risk patients with CIN represent the most problematic patients of this pathology.

Quantitative and qualitative analyses of urinary L-FABP for predicting acute kidney injury after emergency laparotomy

PURPOSE

The aim of this study was to explore the clinical utility of urinary L-FABP for earlier prediction of acute kidney injury (AKI) after emergency laparotomy, and to assess the clinical utility of a point-of-care (POC) kit for urinary L-FABP.

METHODS

Forty-eight patients undergoing emergency laparotomy were divided into AKI and non-AKI groups by the kidney diseases: improving global outcome (KDIGO) criteria. Ten patients were included in the AKI group. Urinary L-FABP, albumin, N-acetyl-β-D-glucosaminidase (NAG), TIMP-2, IGFBP7, serum creatinine (SCr), and blood presepsin were measured perioperatively and compared between groups. Perioperative urinary L-FABP was also evaluated qualitatively using a POC kit.

RESULTS

L-FABP and albumin levels were significantly higher in the AKI group at all measurement points. NAG was significantly higher only postoperatively in the AKI group. There were no inter-group differences in [TIMP-2] × [IGFBP7] at any measuring point. The area under the receiver operating characteristic curve of urinary L-FABP was greater than 0.8 perioperatively, which was larger than that of other biomarkers throughout the study period. The correlation coefficient at 2 h after entering the operating room between quantitative and qualitative tests for urinary L-FABP was 0.714, which was the maximum. The sensitivity, specificity, and negative predictive value of the urinary L-FABP POC kit at 2 h after entry were 55.6%, 91.9%, and 89.5%, respectively.

CONCLUSION

Quantitative L-FABP analyses is suitable for predicting postoperative AKI earlier in the perioperative period of emergency laparotomy. Conversely, the higher specificity of qualitative L-FABP analysis suggests that it may be useful for excluding the risk of AKI but its overall clinical validity should be further investigated.

Usefulness of Adding Pre-procedural Glycemia to the Mehran Score to Enhance Its Ability to Predict Contrast-induced Kidney Injury in Patients Undergoing Percutaneous Coronary Intervention Development and Validation of a Predictive Model

The Mehran score is the most widely accepted tool for predicting contrast-induced acute kidney injury (CI-AKI), a major complication of percutaneous coronary intervention (PCI). Similarly, abnormal fasting pre-procedural glycemia (FPG) represents a modifiable risk factor for CI-AKI, but it is not included in current risk models for CI-AKI prediction. We sought to analyze whether adding FPG to the Mehran score improves its ability to predict CI-AKI following PCI. We analyzed 671 consecutive patients undergoing PCI (age 69 [63,75] years, 23% females), regardless of their diabetic status, to derive a revised Mehran score obtained by including FPG in the original Mehran score (Derivation Cohort). The new risk model (GlyMehr) was externally validated in 673 consecutive patients (Validation Cohort) (age 69 [62,76] years, 21% females). In the Derivation Cohort, both FPG and the original Mehran score predicted CI-AKI (AUC 0.703 and 0.673, respectively). The GlyMehr score showed a better predictive ability when compared with the Mehran score both in the Derivation Cohort (AUC 0.749, 95%CI 0.662 to 0.836; p = 0.0016) and the Validation Cohort (AUC 0.848, 95%CI, 0.792 to 0.903; p = 0.0008). In the overall population (n = 1344), the GlyMehr score confirmed its independent and incremental predictive ability regardless of diabetic status (p ≤0.0034) or unstable/stable coronary syndromes (p ≤0.0272). In conclusion, adding FPG to the Mehran score significantly enhances our ability to predict CI-AKI. The GlyMehr score may contribute to improve the clinical management of patients undergoing PCI by identifying those at high risk of CI-AKI and potentially detecting modifiable risk factors.

Angiotensin-Converting Enzyme Inhibitors and Contrast-Associated Acute Kidney Injury After Coronary Angiography and Intervention

Contrast-associated acute kidney injury has multiple definitions, but is generally described as worsening renal function after administration of iodinated contrast media. It is associated with high in-hospital mortality and poor long-term survival. Furthermore, patients undergoing coronary angiography commonly have comorbidities such as hypertension or congestive heart failure, which are often treated with renin-angiotensin-aldosterone system-blocking agents such as angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. Trials assessing the effects of these renin-angiotensin-aldosterone system-blocking agents on the subsequent development of contrast-associated acute kidney injury have shown conflicting data, suggesting both beneficial and harmful effects. Therefore, there are no clear guidelines on whether clinicians should discontinue renin-angiotensin-aldosterone system-blocking agents peri-procedurally. In this article, we review the data from trials assessing the effects of peri-procedural renin-angiotensin system-blocking agent use in patients undergoing coronary and peripheral angiography and intervention. Future studies will likely focus on the extent of damage or potential benefit of these agents on renal function, cardiac function, as well as morbidity and mortality. Currently, there is insufficient evidence to recommend discontinuation of angiotensin-converting enzyme inhibitors prior to coronary angiography.

Contrast-Induced Nephropathy in Patients Undergoing Staged Versus Concomitant Transcatheter Aortic Valve Implantation and Coronary Procedures

Background

The impact of staged versus concomitant coronary procedures on renal function in patients with aortic stenosis undergoing transcatheter aortic valve implantation (TAVI) remains unclear.

Methods and Results

Three‐hundred thirty‐nine patients undergoing coronary procedures and TAVI as a staged strategy (160, 47.2%) or concomitant strategy (179, 52.8%) were retrospectively analyzed. Contrast‐induced acute kidney injury (CI‐AKI) occurred in 49 patients in the staged strategy group (30.6%) and in 18 patients (10.1%) in the concomitant strategy group (P<0.001). Among the staged strategy group, 25 (15.6%) patients developed CI‐AKI after coronary angiography or percutaneous coronary intervention, 17 (10.6%) after TAVI, and 7 (4.3%) after both the procedures. Staged strategy was associated with a higher risk of CI‐AKI (odds ratio, 3.948; P<0.001) after adjustment for multiple confounders and regardless of the baseline renal function (P for interaction=0.4) when compared with the concomitant strategy. At a median follow‐up of 24.0 months (3.0–35.3), CI‐AKI was not associated with sustained renal injury (P=0.794), irrespective of the adopted strategy. The concomitant strategy did not impact the overall early safety at 30 days follow‐up after TAVI compared to the staged strategy (P=0.609).

Conclusions

Performing coronary procedures with a staged strategy before TAVI was associated with a higher risk of CI‐AKI compared with a concomitant strategy. Moreover, a concomitant strategy did not increase the risk of procedure‐related complications.

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.

Association of Early and Late Contrast-Associated Acute Kidney Injury and Long-Term Mortality in Patients Undergoing Coronary Angiography

Background

Contrast-associated acute kidney injury (CA-AKI) is a common complication in patients undergoing coronary angiography (CAG). However, few studies demonstrate the association between the prognosis and developed CA-AKI in the different periods after the operation.

Methods

We retrospectively enrolled 3206 patients with preoperative serum creatinine (Scr) and at least twice SCr measurement after CAG. CA-AKI was defined as an increase ≥50% or ≥0.3 mg/dL from baseline in the 72 hours after the procedure. Early CA-AKI was defined as having the first increase in SCr within the early phase (<24 hours), and late CA-AKI was defined as an increase in SCr that occurred for the first time in the late phase (24–72 hours). The first endpoint of this study was long-term all-cause mortality. Kaplan–Meier analysis was used to count the cumulative mortality, and the log-rank test was used to assess differences between curves. Univariate and multivariate cox regression analyses were performed to assess whether patients who developed different type CA-AKI were at increased risk of long-term mortality.

Results

The number of deaths in the 3 groups was 407 for normal (12.7%), 106 for early CA-AKI (32.7%) and 57 for late CA-AKI (17.7%), during a median follow-up period of 3.95 years. After adjusting for important clinical variables, early CA-AKI (HR = 1.33, 95% CI: 1.02–1.74, P=0.038) was significantly associated with mortality, while late CA-AKI (HR = 0.92, 95% CI: 0.65–1.31, P=0.633) was not. The same results were found in patients with coronary artery disease, chronic kidney disease, diabetes mellitus, and percutaneous coronary intervention.

Conclusions

Early increases in Scr, i.e., early CA-AKI, have better predictive value for long-term mortality. Therefore, in clinical practice, physicians should pay more attention to patients with early renal injury related to long-term prognosis and give active treatment.

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.

Trajectory of renal function change and kidney injury after percutaneous coronary intervention in patients with stable coronary artery disease

Acute kidney injury usually assessed within 48 h after percutaneous coronary intervention (PCI) is associated with poor clinical outcomes, and persistent kidney damage is also strongly related to long-term mortality. However, little is known about longitudinal renal function change from a very early period to long-term follow-up after PCI. A total of 327 patients with stable coronary artery disease underwent elective PCI. Renal function was assessed with serum creatinine levels and estimated glomerular filtration rate (eGFR) at baseline, 1 day after PCI, at 1 year and at the latest follow-up. Kidney injury was defined as an increase in creatinine levels ≥ 0.3 mg/dl or ≥ 50% from baseline at each timepoint. Major adverse cardiovascular events (MACE) was defined as a composite of death, myocardial infarction, and stroke. eGFR was significantly increased 1 day after PCI, while it was progressively decreased at 1-year and long-term follow-up (median 28 months). Overall, eGFR was declined by - 2.3 ml/min/1.73 m² per year. Only one (0.3%) patient developed kidney injury 1 day after PCI, whereas kidney injury at 1-year and long-term follow-up was observed in 15 (4.6%) and 27 (8.3%). During the follow-up period, 23 (7.0%) patients had MACE. The incidence of subsequent MACE was significantly higher in patients with kidney injury at 1 year than those without. In conclusion, kidney injury within 24 h after elective PCI was rarely observed. eGFR was progressively decreased over time, and mid-term kidney injury at 1 year was associated with future MACE.

Rotational atherectomy-based percutaneous coronary intervention and the risk of contrast-induced nephropathy

BACKGROUND

Rotational atherectomy (RA)-related complications (e.g., no-reflow and perforation) may be associated with increased risk of contrast-induced nephropathy (CIN), causing hypotension, acute heart failure, and periprocedural myocardial infarction. Our aim was to evaluate the incidence of CIN in patients undergoing RA-based vs. non-RA-based percutaneous coronary intervention (PCI).

METHODS

This single-center retrospective registry included all patients who underwent PCI between 2012 and 2016 for whom post-procedural creatinine was determined. Study endpoint was CIN, defined as an increase of serum creatinine ≥0.3 mg/dL or ≥50% from baseline within 72 h post-PCI. Propensity score matching (PSM) was performed to account for selection bias between RA and non-RA patients.

RESULTS

Study population included 2580 patients: 70 (3%) had RA PCI and 2510 (97%) had non-RA PCI. Following PSM, there were 70 patients in RA and 280 patients in non-RA group with good overall adjustment between groups, although RA patients received larger contrast volume (263±126 vs. 224±118 mL, P=0.01) and showed higher Mehran risk score at baseline (11.1±6.6 vs. 8.9±4.8, P=0.01). The incidence of CIN was similar between RA and non-RA patients (15.7% vs. 13.2%, P=0.59). New need for dialysis was required in 0% vs. 0.7% patients, respectively (P=0.48). On multivariate analysis, RA PCI was not independently associated with development of CIN.

CONCLUSIONS

Despite being performed in patients with a higher burden of comorbidities and with larger volumes of contrast, RA PCI is not associated with higher risk of CIN, compared with PCI in non-RA patients.

The effect of time between angiography and coronary artery bypass grafting on postoperative acute kidney injury in patients with diabetes mellitus

Background

This study aims to investigate the effect of time interval between coronary angiography and coronary artery bypass grafting surgery on postoperative acute kidney injury in patients with diabetes mellitus.

Methods

Between December 2013 and November 2016, a total of 421 diabetic patients (274 males, 147 females; mean age 60±9.2 years; range, 31 to 84 years) who underwent coronary artery bypass grafting were included in the study. Data including demographic characteristics of the patients, comorbidities, medical, and surgical histories, previous coronary angiographies, and operative and laboratory results were retrospectively analyzed. The patients were divided into two groups as those with acute kidney injury (n=108) and those without acute kidney injury (n=313). The Risk, Injury, Failure, Loss, End-Stage Kidney Disease (RIFLE) criteria were used to define acute kidney injury. The patients were further classified into three subgroups according to the time interval: 0-3 days, 4-7 days, and >7 days.

Results

There was no statistically significant difference in the median time between coronary angiography and coronary artery bypass grafting between the patients with and without acute kidney injury (11.5 and 12.0 days; respectively p=0.871). There was no significant difference in the risk factors for acute kidney injury among the subgroups. Multivariate analysis revealed that previous myocardial infarction (odds ratio [OR]: 5.192, 95% confidence interval [CI]: 2.176-12.38; p<0.001) and the increase in the creatinine levels in the first postoperative day (OR: 4.102 and 95% CI: 1.278- 13.17; p=0.018) were independent predictors of acute kidney injury.

Conclusion

Coronary artery bypass grafting can be performed without any delay after coronary angiography without an increase in the postoperative risk of acute kidney injury in patients with diabetes mellitus.

Acute Renal Failure of Nosocomial Origin

BACKGROUND

10-20% of hospitalized patients develop acute kidney injury (AKI)/acute renal failure during their hospital stay. The mortality of nosocomial AKI is approximately 30%.

METHODS

This review is based on relevant publications retrieved by a search in multiple databases (PubMed and Uptodate), archives, and pertinent medical journals.

RESULTS

The most common causes of nosocomial AKI are volume depletion, sepsis, heart diseases, polytrauma, liver diseases, and drug toxicity. AKI can also be of postrenal (obstructive) origin, or a result of renal diseases including glomeruloneph- ritis, vasculitis, tubulointerstitial nephritis, and cholesterol embolism. In about 13% of cases, nosocomial AKI develops on the basis of pre-existing chronic renal disease. Patients with AKI are at elevated risk of developing chronic renal disease and must be followed up appropriately after they are discharged from the hospital. Indispens- able elements of the evaluation of nosocomial AKI include renal ultrasonography, the exclusion of postrenal obstruction, urine chemistry, and microbiological urinaly- sis. Potentially nephrotoxic drugs and those that impair renal hemodynamics must be avoided to the greatest possible extent in patients with acute renal damage. Hypotension must be avoided as well.

CONCLUSION

Early, specific nephrological diagnosis and treatment are important components of the management of nosocomial AKI, particularly because causally directed treatment is available for some of the conditions that underlie it.

Radiological iodinated contrast-induced nephropathy

The use of iodinated contrast media can cause renal toxicity. Whether contrast media are exclusively responsible for kidney damage is currently the subject of debate, given that in most cases, other potential causes of the renal failure are present. With current low-osmolar and iso-osmolar contrast media, the incidence rate of contrast-induced nephropathy is estimated to be <1% in the low-risk population but can increase to 37% in patients who are administered contrast by an intra-arterial administration and/or who have renal failure with an estimated glomerular filtration rate (eGFR) <30mL/min/1.73m². To minimize the risk of renal toxicity, the recommendation is to administer the least amount of contrast possible and ensure appropriate volume expansion by infusing 0.9% saline solution.

Periprocedural myocardial and renal injury in patients undergoing elective percutaneous coronary interventions - is there an association?

Periprocedural myocardial injury (PMI) and contrast-induced nephropathy (CIN) are frequent complications of percutaneous coronary intervention (PCI) associated with early and late major adverse cardiovascular events. Both conditions are associated with similar risk factors, which could imply their possible association. The aim of our study was to assess the correlation of PMI and early postprocedural creatinine shift (ECS) as a marker of renal injury.A total of 209 hospitalized patients with stable coronary artery disease (CAD) were enrolled, who underwent an elective PCI in a period of 12 months. All patients had their serum high-sensitivity troponin I (hsTnI) measured at baseline and 16 hours after the PCI. PMI was defined according to the elevation of postprocedural hsTnI using criteria provided by both the most recent consensus documents as well as evidence-based data. Renal injury was evaluated using the ECS concept. Serum creatinine (SCr) was also measured at baseline and at 16 hours. ECS was defined as SCr >5% at 16 hours compared to baseline.Although incidence of both PMI (77.5%) and ECS (44.5%) were high, no association of these 2 conditions could be found. Further analyses of our data showed that diabetes is associated with a higher incidence of ECS, while patients on beta-blocker therapy had a lower incidence of ECS.In our study, no association between PMI and ECS was found. Additional studies with a larger number of patients and longer patient observation are needed to assess the correlation between PMI and CIN as well as to validate the attractive, but controversial, concept of ECS as an early marker of CIN.

l-Proline Alleviates Kidney Injury Caused by AFB1 and AFM1 through Regulating Excessive Apoptosis of Kidney Cells

The toxicity and related mechanisms of aflatoxin B1 (AFB1) and aflatoxin M1 (AFM1) in the mouse kidney were studied, and the role of l-proline in alleviating kidney damage was investigated. In a 28-day toxicity mouse model, thirty mice were divided into six groups: control (without treatment), l-proline group (10 g/kg body weight (b.w.)), AFB1 group (0.5 mg/kg b.w.), AFM1 (3.5 mg/kg b.w.), AFB1 + l-proline group and AFM1 + l-proline group. Kidney index and biochemical indicators were detected, and pathological staining was observed. Using a human embryonic kidney 293 (HEK 293) cell model, cell apoptosis rate and apoptotic proteins expressions were detected. The results showed that AFB1 and AFM1 activated pathways related with oxidative stress and caused kidney injury; l-proline significantly alleviated abnormal expressions of biochemical parameters and pathological kidney damage, as well as excessive cell apoptosis in the AF-treated models. Moreover, proline dehydrogenase (PRODH) was verified to regulate the levels of l-proline and downstream apoptotic factors (Bax, Bcl-2, and cleaved Caspase-3) compared with the control (p < 0.05). In conclusion, l-proline could protect mouse kidneys from AFB1 and AFM1 through alleviating oxidative damage and decreasing downstream apoptosis, which deserves further research and development.

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.

The Toxic Effects of Aflatoxin B1 and Aflatoxin M1 on Kidney through Regulating L-Proline and Downstream Apoptosis

The toxic effects and potential mechanisms of aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), and AFB1+AFM1 in the kidney were studied and compared in HEK 293 cells model and CD-1 mice model. The 35-day subacute toxicity mice model was constructed, biochemical indicators and kidney pathological staining were detected, kidney metabonomics detection was performed, and the metabolites were analyzed, and then the related toxicity mechanism was validated. Results showed that AFB1 (0.5 mg/kg), AFM1 (3.5 mg/kg), and AFB1 (0.5 mg/kg)+AFM1 (3.5 mg/kg) activated oxidative stress and caused renal damage. The relative concentration of the metabolite L-proline was found to be lower in aflatoxins treatment groups when compared with the control (P < 0.05). Moreover, with the treatment of aflatoxins, proline dehydrogenase (PRODH) and proapoptotic factors (Bax, Caspase-3) were upregulated, while the inhibitor of apoptosis Bcl-2 was downregulated, at both the mRNA and the protein levels, comparing with the control (P < 0.05). In addition, the combined effect of AFB1 and AFM1 was validated, for the toxicity of the combination was stronger than the other two groups. In conclusion, AFB1 and AFM1 caused kidney toxicity by activating oxidative stress through altering expression of PRODH and L-proline levels, which then induced downstream apoptosis.

The Toxic Effects of Aflatoxin B1 and Aflatoxin M1 on Kidney through Regulating L-Proline and Downstream Apoptosis

The toxic effects and potential mechanisms of aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), and AFB1+AFM1 in the kidney were studied and compared in HEK 293 cells model and CD-1 mice model. The 35-day subacute toxicity mice model was constructed, biochemical indicators and kidney pathological staining were detected, kidney metabonomics detection was performed, and the metabolites were analyzed, and then the related toxicity mechanism was validated. Results showed that AFB1 (0.5 mg/kg), AFM1 (3.5 mg/kg), and AFB1 (0.5 mg/kg)+AFM1 (3.5 mg/kg) activated oxidative stress and caused renal damage. The relative concentration of the metabolite L-proline was found to be lower in aflatoxins treatment groups when compared with the control (P < 0.05). Moreover, with the treatment of aflatoxins, proline dehydrogenase (PRODH) and proapoptotic factors (Bax, Caspase-3) were upregulated, while the inhibitor of apoptosis Bcl-2 was downregulated, at both the mRNA and the protein levels, comparing with the control (P < 0.05). In addition, the combined effect of AFB1 and AFM1 was validated, for the toxicity of the combination was stronger than the other two groups. In conclusion, AFB1 and AFM1 caused kidney toxicity by activating oxidative stress through altering expression of PRODH and L-proline levels, which then induced downstream apoptosis.

Oxidative stress and kidney injury in trans-radial catheterization

Oxidative stress is linked to coronary artery disease and is a major mechanism in contrast-induced nephropathy. Trans-radial approach in coronary angiography (CA) with minimized peri-procedural bleeding is expected to reduce acute kidney injury incidence. In the present study, oxidative stress patterns observed in radial CA and their associations with early manifestations of kidney injury are described. A total of 20 stable coronary disease patients submitted to CA and 17 sex-matched patients undergoing computed tomography for myoskeletal reasons were enrolled. Reduced glutathione, catalase, thiobarbituric acid reactive species (TBARS) levels and total anti-oxidant status were measured at various time points postangiography. In ischemic patients baseline TBARS levels were 2-fold lower compared to controls, while carbonyls levels were 35% higher. Glutathione was almost 4-fold lower than the control group. Glutathione and lipid peroxidation in ischemic patients gradually increased after contrast medium administration and reached 180% (P<0.001) and 20% (P=0.021) after 4–6 h, respectively. Four patients presented early evidence of contrast-induced nephropathy postangiography, while no control patient developed acute kidney injury. In the multiple logistic regression analysis, only the creatinine levels at baseline influenced the frequency of early contrast-induced nephropathy development (β =0.36, 95% CI: 0.285–0.438, P=0.01). Glutathione low levels were dominant in the baseline values of ischemic patients who developed contrast-induced nephropathy. Glutathione levels rapidly increased while protein oxidation decreased at the expense of lipid peroxidation. In conclusion, early oxidative stress changes occur in trans-radial CA patients with a mild profile, sufficient to mobilize patient antioxidant defenses.

Could late measurement of serum creatinine be missed for patients without early increase in serum creatinine following coronary angiography?

Most patients are discharged early (within 24 hours) after coronary angiography (CAG) and may miss identification the late (24-48 hours) increase in serum creatinine (SCr), whose characteristics and prognosis have been less intensively investigated.We prospectively recruited 3065 consecutive patients with SCr measurement, including only1344 patients with twice SCr measurement (both early and late). The late contrast-induced acute kidney injury (CI-AKI) was defined as significantly increase in SCr (≥0.3 mg/dL or ≥50%) not in early phase, but only in late phase after the procedure, and the early CI-AKI experienced a significantly increase in early phase.Overall, CI-AKI developed in 134 patients (10%), and the incidence of late and early CI-AKI were 3.6% and 6.4%, respectively. There were no difference in age, renal, and heart function, contrast volume among patients with late and early CI-AKI. With mean follow-up period of 2.45 years, long-term mortality (3 years, 29.7% and 35.6%, respectively, P = .553) was similar for patients with late and early CI-AKI. Cox analysis showed that both late (adjusted HR 2.05; 95% CI, 1.02-4.15) and early (adjusted HR 2.68; 95% CI, 1.57-4.59) CI-AKI was significantly associated with long-term mortality (all P < .001).Only late increase in SCr, as late CI-AKI, accounted for about one-third of CI-AKI incidence and has similar good predictive value for long-term mortality with that of an early increase, early CI-AKI, among patients with SCr measured twice, supporting the importance of late repeating SCr measurement after CAG, even without an early significant increase in SCr.

Contrast media-induced nephropathy: how has Italy contributed in the past 30 years? A systematic review

Background and objective

The use of contrast media in Italy has exponentially increased in the past 3 decades. However, it is unknown whether there has been an increase in clinical research evaluating the risks associated with contrast media usage, especially regarding contrast-induced nephropathy. To fill this gap in knowledge, we performed a systematic review.

Study eligibility criteria

Meta-analyses, observational studies, and clinical trials assessing contrast media-induced nephropathy as the safety outcome, in which at least one author was affiliated with an Italian university/health care structure, were eligble.

Data sources

Ovid MEDLINE, Ovid Embase, Cochrane Methodology Register, and Web of Science were screened.

Participants

Men and women exposed to contrast media.

Results

In total, 60 original articles were retrieved with an incremental trend between 1990 and 2017. Cohort studies were the most common study design represented. In total, 45 of 60 (75.0%) studies were monocenter studies and 41 of 60 (68.3%) received no funding. In all, 91.7% of studies disclosed no conflicts of interest and 81.7% had no external collaboration. Most of the studies provided a level of evidence of III-2 (32/60; 53.3%) and II (23/60; 38.3%). In total, 50 of 60 studies (83.3%) were published in a scientific journal ranked in the first quartile of their subject area.

Conclusion

There was an increased number of studies evaluating contrast-induced nephropathy in Italy during the last three decades. These studies covered procedures to prevent contrast-induced nephropathy or aimed to identify risk factors, biomarkers, and scores, and their related prognosis.

Association of post-procedural early (within 24h) increases in serum creatinine with all-cause mortality after coronary angiography

BACKGROUND

The majority of patients undergoing coronary angiography (CAG) or percutaneous coronary intervention (PCI) are discharged early, with only early (within 24h) serum creatinine (SCr) data available without evidence of clinical prognosis. We aimed to systemically evaluate the association between post-procedural early increase in SCr and all-cause mortality following CAG.

METHODS

We performed a retrospective sub-study analysis within a prospective observational study including 3091 consecutive patients with baseline and post-procedural early (within 24h) SCr data. The degree (mild, moderate, or large) of absolute and relative increases in SCr from baseline. The mean follow-up time was 2.49years.

RESULT

Moderate or large early increases in SCr were relatively rare (large increase: >1.0mg/dl [0.5%], >100% [0.4%]), whereas mild absolute and relative increases in SCr were more common (mild increase: 0.25 to 0.50mg/dl [4.5%], 25% to 50% [5.9%]). During the follow-up period, there were 136 post-procedural deaths (5.6%). After adjustment for confounders, mild absolute and relative increases in SCr were associated with increased mortality (hazard ratio [HR]: 1.9 and 1.8, respectively, both P<0.05). Moderate or large increases in SCr were associated with higher mortality, even higher than with pre-existing renal dysfunction (HR: 5.36 and 4.12 for moderate increase [0.5 to 1.0mg/dl] and estimated glomerular filtration rate<60ml/min).

CONCLUSION

Post-procedural mild, moderate, or large early increase in SCr, is associated with significantly increased long-term mortality. Although moderate or large increase in SCr following CAG was relatively rare, the prognosis is more serious, and is worse than that of pre-existing renal dysfunction.

CLINICAL TRIAL REGISTRATION

Predictive Value of Contrast Volume to Creatinine Clearance Ratio (PRECOMIN, ClinicalTrials.govNCT01400295).

Contrast-induced acute kidney injury: A review of practical points

Contrast-induced acute kidney injury (CI-AKI) is one of the most common causes of AKI in clinical practice. CI-AKI has been found to be strongly associated with morbidity and mortality of the patients. Furthermore, CI-AKI may not be always reversible and it may be associated with the development of chronic kidney disease. Pathophysiology of CI-AKI is not exactly understood and there is no consensus on the preventive strategies. CI-AKI is an active research area thus clinicians should be updated periodically about this topic. In this review, we aimed to discuss the indications of contrast-enhanced imaging, types of contrast media and their impact on nephrotoxicity, major pathophysiological mechanisms, risk factors and preventive strategies of CI-AKI and alternative non-contrast-enhanced imaging methods.

Comparative Effectiveness of 12 Treatment Strategies for Preventing Contrast-Induced Acute Kidney Injury: A Systematic Review and Bayesian Network Meta-analysis

BACKGROUND

To simultaneously evaluate the relative efficacy of multiple pharmacologic strategies for preventing contrast-induced acute kidney injury (AKI).

STUDY DESIGN

Systematic review containing a Bayesian network meta-analysis of randomized controlled trials.

SETTING & POPULATION

Participants undergoing diagnostic and/or interventional procedures with contrast media.

SELECTION CRITERIA FOR STUDIES

Randomized controlled trials comparing the active drug treatments with each other or with hydration alone.

INTERVENTION

Any of the following drugs in combination with hydration: N-acetylcysteine (NAC), theophylline (aminophylline), fenoldopam, iloprost, alprostadil, prostaglandin E₁, statins, statins plus NAC, bicarbonate sodium, bicarbonate sodium plus NAC, ascorbic acid (vitamin C), tocopherol (vitamin E), α-lipoic acid, atrial natriuretic peptide, B-type natriuretic peptide, and carperitide.

OUTCOMES

The occurrence of contrast-induced AKI.

RESULTS

The trial network included 150 trials with 31,631 participants and 4,182 contrast-induced AKI events assessing 12 different interventions. Compared to hydration, ORs (95% credible intervals) for contrast-induced AKI were 0.31 (0.14-0.60) for high-dose statin plus NAC, 0.37 (0.19-0.64) for high-dose statin alone, 0.37 (0.17-0.72) for prostaglandins, 0.48 (0.26-0.82) for theophylline, 0.62 (0.40-0.88) for bicarbonate sodium plus NAC, 0.67 (0.54-0.81) for NAC alone, 0.64 (0.41-0.95) for vitamins and analogues, 0.70 (0.29-1.37) for natriuretic peptides, 0.69 (0.31-1.37) for fenoldopam, 0.78 (0.59-1.01) for bicarbonate sodium, and 0.98 (0.41-2.07) for low-dose statin. High-dose statin plus NAC or high-dose statin alone were likely to be ranked the best or the second best for preventing contrast-induced AKI. The overall results were not materially changed in metaregressions or subgroup and sensitivity analyses.

LIMITATIONS

Patient-level data were unavailable; unable to include some treatment agents; low event rates; imbalanced distribution of participants among treatment strategies.

CONCLUSIONS

High-dose statins plus hydration with or without NAC might be the preferred treatment strategy to prevent contrast-induced AKI in patients undergoing diagnostic and/or interventional procedures requiring contrast media.

Strategies for assessing renal function prior to outpatient contrast-enhanced CT: a UK survey

OBJECTIVE

To identify current UK screening practices prior to contrast-enhanced CT. To determine the patient management strategies to minimize the risk of contrast-induced acute kidney injury (CI-AKI) risk in outpatients.

METHODS

An invitation to complete an electronic survey was distributed to the CT managers of 174 UK adult National Health Service hospital trusts. The survey included questions related to local protocols and national guidance on which these are based. Details of the assessment of renal function prior to imaging and thresholds for contrast contraindication and patient management were also sought.

RESULTS

A response rate of 47.1% was received. Almost all sites had a policy in place for contrast administration (n = 80/82; 97.6%). The majority of sites require a blood test on outpatients undergoing a contrast-enhanced CT scan (n = 75/82; 91.5%); however, some (15/75; 20.0%) sites only check the result in patients at high risk and a small number (7/82; 8.5%) of sites indicated that it was a referrer responsibility. The estimated glomerular filtration rate (eGFR) or serum creatinine (SCr) result threshold at which i.v. contrast was contraindicated varied and 19 different threshold levels of eGFR or SCr were identified, each leading to different prophylactic strategies. Inconsistency was noted in the provision of follow-up blood tests after contrast administration.

CONCLUSION

The wide variation in practice reflects inconsistencies in published guidance. Evidence-based consensuses of which patients to test and subsequent risk thresholds will aid clinicians identify those patients in which the risk of CI-AKI is clinically significant but manageable. There is also a need to determine the value of the various prophylactic strategies, follow-up regimen and efficient service delivery pathways. Advances in knowledge: This survey has identified that further work is required to define which patients are high risk, confirm those which require renal function testing prior to contrast administration and how best to manage patients at risk of CI-AKI. The role of new technologies within this service delivery pathway requires further investigation.

Long-Term (3 Years) Prognosis of Contrast-Induced Acute Kidney Injury After Coronary Angiography

Contrast-induced acute kidney injury (CI-AKI) after coronary angiography or interventions is relatively frequent and portends adverse outcomes. The lack of a "universally accepted" definition, however, limits the integration and comparison of available data. We aimed to detect the CI-AKI definition that best correlates with the occurrence of clinical events at long-term in a 3-year follow-up study of patients at intermediate-to-high risk for CI-AKI. Furthermore, we sought to describe the incidence and long-term evolution of persistent renal damage (PRD) after CI-AKI and clarify the role of early (<12 hours) increments of serum creatinine (SCr) in CI-AKI prediction. Among a total of 216 patients enrolled at our center and followed for a median of 37 months, CI-AKI was diagnosed in 18.1% of cases (SCr increment ≥25% of baseline), 7.4% (SCr increment ≥0.5 mg/dl), and in 17.1% (SCr increment ≥0.3 mg/dl), according to 3 different definitions. The third definition was the only one significantly associated with the occurrence of events at 3 years (Cox regression, p = 0.04). PRD at 30 days, as detected by the same cutoff, significantly and independently identified patients at risk of worst outcomes at 3 years (p = 0.04 at multivariate Cox regression). Furthermore, a slight 5% to 10% increment of SCr compared with baseline, occurring as early as 12 hours postprocedure, was confirmed as a strong predictor of inhospital CI-AKI occurrence. In conclusion, an absolute increase in SCr ≥0.3 mg/dl seems to be most clinically informative cutoff for CI-AKI and PRD detection.

Pathogenesis of renal failure in multiple myeloma: any role of contrast media?

The spectrum of kidney disease-associated monoclonal immunoglobulin and plasma cell malignancies is remarkably broad and encompasses nearly all nephropathologic entities. Multiple myeloma with kidney impairment at presentation is a medical emergency since the recovery of kidney function is associated with survival benefits. In most cases, kidney impairment may be the first clinical manifestation of malignant plasma cell dyscrasias like multiple myeloma and light chain amyloidosis. Multiple myeloma per se cannot be considered a main risk factor for developing acute kidney injury following intravascular administration of iodinated contrast media. The risk is increased by comorbidities such as chronic kidney disease, diabetes, hypercalcemia, dehydration, and use of nephrotoxic drugs. Before the administration of contrast media, the current recommended laboratory tests for assessing kidney function are serum creatinine measurement and the estimation of glomerular filtration rate by using the CKD-EPI equation. The assessment of Bence Jones proteinuria is unnecessary for evaluating the risk of kidney failure in patients with multiple myeloma, since this test cannot be considered a surrogate biomarker of kidney function.

A simple preprocedural score for risk of contrast-induced acute kidney injury after percutaneous coronary intervention

OBJECTIVE

To develop a simple scoring system based on preprocedural clinical features that is capable of predicting contrast-induced acute kidney injury (CI-AKI) before percutaneous coronary intervention (PCI).

BACKGROUND

CI-AKI is associated with increased in-hospital morbidity and mortality, prolonged hospitalization, and long-term renal impairment. Although several scoring methods have been developed to determine risk of CI-AKI, no simple scoring method based on PCI preprocedural clinical features yet exists for Chinese patients.

METHODS

A total of 2,500 Chinese patients were randomly and retrospectively assigned in a 3:2 manner to create a training and validation dataset, respectively. CI-AKI was defined as an increase of ≥25% or ≥0.5 mg/dL serum creatinine within 5 days after PCI. Preprocedural clinical variables showing independent correlation to CI-AKI were used to derive the risk score from the training dataset and then subsequently tested in the validation dataset. The odds ratios from multivariate logistic regression were used to assign a weighted integer to age ≥70 years = 4, history of myocardial infarction = 5, diabetes mellitus = 4, hypotension = 6, left ventricular ejection fraction ≤45% = 4, anemia = 3, creatinine clearance rate <60 mL/min = 7, decreased high-density lipoprotein <1 mmol/L= 3, and urgent PCI = 3. Summation of the integers represented the total risk score.

RESULTS

The overall incidence of CI-AKI in the training dataset was 16.4% [246/1500; 5.4% for low (≤7) and 61.3% for very high (≥17) risk scores]. The rates of CI-AKI, 1-year dialysis, and 1-year mortality increased significantly with each group (Cochran-Armitage test of trend, P < 0.001). The risk score facilitated appropriate classification of patients with low and high risk for CI-AKI after PCI in the validation dataset (c-statistic = 0.82).

CONCLUSION

Risk classification based on the most significantly correlated parameters is useful for predicting CI-AKI before contrast exposure. The simple preprocedural score showed excellent predictive ability for identifying patients at high risk of nephropathy and those with deteriorative prognosis after PCI.

Early renal dysfunction after contrast media administration despite prophylactic hydration

The actual incidence of renal dysfunction after contrast media administration seems to be underestimated, especially in the context of epidemiological data. There are only few data concerning the monitoring of impaired kidney function within a few hours after iodine contrast medium application. Hence, the purpose of this study is to observe the incidence of early renal function deterioration within 12–18 h after administration of iodine contrast media in patients scheduled for elective coronary angiography, who were intravenously and orally hydrated. In addition, the project aims to reclassify the contrast induced nephropathy phenomenon, by identification of early markers of renal dysfunction. Morphology, electrolytes, blood urea nitrogen (BUN), creatinine, low-density lipoprotein cholesterol, triglycerides, high-density lipoprotein, and total cholesterol levels were assessed with the use of typical laboratory techniques in 319 patients referred for coronary angiography. We demonstrated that early deterioration of renal function in patients 12–18 h after administration of contrast during imaging tests (even when appropriate prophylactic hydration was used), may occurred just as an increase (or no change) of serum creatinine level and BUN level and a decrease of creatinine clearance and glomerular filtration rate. Depending on the parameter, the phenomenon can be found in 13–28 % of all respondents. Early renal function impairment defined as above was almost 2 and 2.22 × 10³ times (respectively) more frequently observed in our study than contrast induced nephropathy defined by current definitions.

Which point-of-care creatinine analyser for radiology: direct comparison of the i-Stat and StatStrip creatinine methods with different sample types

BACKGROUND

Availability of whole blood creatinine estimation for patients scheduled to undergo radiological contrast investigations can provide information to aid patient care by reducing adverse effects and improving departmental efficiencies.

METHODS

We performed imprecision studies, different patient sample type comparison in 40 participants, and a limited interference study with dopamine and dobutamine on the i-Stat and StatStrip point-of-care enzymatic analysers with the Beckman DxC800 Jaffe assay.

RESULTS

Imprecision results showed that the i-Stat performed better. Patient comparison data indicated that the i-Stat provided better correlation than the StatStrip for all the different sample types with correlation coefficients (r(2)) being 0.995-0.996 and 0.918-0.995, respectively. The i-Stat results had a small positive bias of 6-9% for the three different sample types, which required different reference intervals. The StatStrip method showed greater scatter and overall small negative bias of -6% for the whole blood samples and a 10% positive bias with the plasma samples. Dopamine caused significant positive interference with the i-Stat only while dobutamine caused a small negative bias with the StatStrip method only.

CONCLUSIONS

The findings indicated there are differences offered by the two systems. The StatStrip requires a very small finger prick capillary sample, calculates estimation of the glomerular filtration rate and has an adjustment option to improve correlation with the local method. The i-Stat offers better analytical imprecision and patient comparison with the laboratory method with the three sample types but showed significant interference from dopamine. A final consideration was the availability of middleware to capture patient results with the i-Stat. Based on all the study data, the i-Stat was recommended.

Comparison of serum creatinine and cystatin C for early diagnosis of contrast-induced nephropathy after coronary angiography and interventions

BACKGROUND

The diagnostic accuracy of serum creatinine and cystatin C (Cys) as early predictors of contrast-induced nephropathy (CIN) has been debated. We investigated the diagnostic sensitivities, diagnostic specificities, and variations from baseline for serum creatinine and Cys in CIN.

METHODS

We prospectively evaluated 166 patients at risk for CIN at baseline, and at 12, 24, and 48 h after exposure to contrast media. CIN occurred in 30 patients (18%). Changes (Δ) compared to baseline in serum creatinine and Cys were evaluated at the predefined time points. ROC curve analysis was performed for the Δ 12-h basal serum creatinine and Cys.

RESULTS

The Δ serum creatinine at 12 h from baseline was the earliest predictor of CIN [area under the ROC curve (AUC) = 0.80; P < 0.001]. The Δ serum creatinine 15% variation [0.15 mg/dL (13.2 μmol/L)] yielded 43% diagnostic sensitivity and 93% diagnostic specificity. The ΔCys at 12 h from baseline performed significantly worse than serum creatinine (AUC = 0.48; P = 0.74).

CONCLUSIONS

Variations from the serum creatinine baseline offer better diagnostic accuracy for predicting CIN at an earlier stage than similar variations in Cys. An additional diagnostic value of Cys over the determination of serum creatinine in the setting of CIN was not observed.