BACKGROUND: Ethylene diamine tetra-acetic acid (EDTA) is a chelating agent used to dissolve calcium deposits but evidence in decalcifying atherosclerotic lesions is limited.
OBJECTIVE: We assessed the feasibility and efficacy of EDTA delivered via porous balloon to target calcified lesions in cadaveric below-the-knee (BTK) arteries.
METHODS: Using porcine carotid arteries, EDTA concentration was measured in the arterial wall and outside the artery at the 0-, 0.5-, 4-, and 24-h circulation after the injection through a porous balloon. In cadaver BTK samples, the proximal and distal anterior tibial artery (ATA) and distal posterior tibial artery (PTA) were studied. EDTA-2Na/H2O or EDTA-3Na/H2O were administrated using a porous balloon, then circulated for 6 h for EDTA-3Na/H2O and 24 h for EDTA-2Na/H2O and EDTA-3Na/H2O. Micro-CT imaging of the artery segments before and after the circulation and cross-sectional analyses were performed to evaluate calcium burden.
RESULTS: In the porcine carotid study, EDTA was delivered through a porous balloon present in the arterial wall and was retained there for 24 h. In BTK arteries, cross-sectional analyses of micro-CT revealed a significant decrease in the calcium area in the distal ATA segment under 24-h circulation with EDTA-2Na/H2O and in the distal ATA segment under 24-h circulation with EDTA-3Na/H2O. The proximal ATA segment under 6-h circulation with EDTA-3Na/H2O showed no significant change in any parameters of calcium CONCLUSION: EDTA-3Na/H2O or EDTA-2Na/H2O with longer circulation times resulted in greater calcium reduction in atherosclerotic lesion. EDTA may have a potential therapeutic option for the treatment of atherosclerotic calcified lesions.

Chronic metabolic acidosis leads to bone-remodelling disorders based on excessive mineral matrix resorption and inhibition of bone formation, but also affects the homeostasis of citrate, which is an essential player in maintaining the acid-base balance and in driving the mineralisation process. This study aimed to investigate the impact of acidosis on the osteogenic properties of bone-forming cells and the effects of citrate supplementation in restoring the osteogenic features impaired by the acidic milieu. For this purpose, human mesenchymal stromal cells were cultured in an osteogenic medium and the extracellular matrix mineralisation was analysed at the micro- and nano-level, both in neutral and acidic conditions and after treatment with calcium citrate and potassium citrate. The acidic milieu significantly decreased the citrate release and hindered the organisation of the extracellular matrix, but the citrate supplementation increased collagen production and, particularly calcium citrate, promoted the mineralisation process. Moreover, the positive effect of citrate supplementation was observed also in the physiological microenvironment. This in vitro study proves that the mineral matrix organisation is influenced by citrate availability in the microenvironment surrounding bone-forming cells, thus providing a biological basis for using citrate-based supplements in the management of bone-remodelling disorders related to chronic low-grade acidosis.

Citric acid-based bicarbonate dialysate (CiD) is increasingly used in haemodialysis (HD) to improve haemodynamic tolerance and haemocompatibility associated with acetic acid-based bicarbonate dialysate. Safety concerns over CiD have been raised recently after a French ecological study reported higher mortality hazard in HD clinics with high CiD consumption. Therefore, we evaluated the mortality risk associated with various acidifiers (AcD, CiD) of bicarbonate dialysate.
In this multicentre, historical cohort study, we included adult incident HD patients (European, Middle-East and Africa Fresenius Medical Care network; 1 January 2014 to 31 October 2018). We recorded acidifiers of bicarbonate dialysis and dialysate composition for each dialysis session. In the primary intention-to-treat analysis, patients were assigned to the exposed group if they received CiD in >70% of sessions during the first 3 months (CiD70%), whereas the non-exposed group received no CiD at all. In the secondary analysis, exposure was assessed on a monthly basis for the whole duration of the follow-up.
We enrolled 10 121 incident patients during the study period. Of them, 371 met the criteria for inclusion in CiD70%. After propensity score matching, mortality was 11.43 [95% confidence interval (CI) 8.86-14.75] and 12.04 (95% CI 9.44-15.35) deaths/100 person-years in the CiD0% and CiD70% groups, respectively (P = 0.80). A similar association trend was observed in the secondary analysis.
We did not observe evidence of increased mortality among patients exposed to CiD in a large European cohort of dialysis patients despite the fact that physicians were more inclined to prescribe CiD to subjects with worse medical conditions.

The NIH-funded Trial to Assess Chelation Therapy (TACT) randomized 1708 stable patients age ≥50 who were ≥6 months post myocardial infarction to 40 infusions of an edetate disodium-based regimen or placebo. In 633 patients with diabetes, edetate disodium significantly reduced the primary composite endpoint of mortality, recurrent myocardial infarction, stroke, coronary revascularization, or hospitalization for angina (hazard ratio [HR] 0.59, 95% confidence interval [CI] 0.44-0.79, p < 0.001). The principal secondary endpoint of a composite of cardiovascular death, myocardial infarction, or stroke was also reduced (HR 0.60, 95% CI 0.39-0.91, p = 0.017). It is unknown if the treatment effect differs by diabetes therapy.
We grouped the subset of 633 patients with diabetes according to glucose-lowering therapy at time of randomization. The log-rank test was used to compare active therapy versus placebo. All treatment comparisons were performed using 2-sided significance tests at the significance level of 0.05 and were as randomized. Relative risks were expressed as HR with associated 95% CI, calculated using the Cox proportional hazards model.
There were 162 (25.7%) patients treated with insulin; 301 (47.5%) with oral hypoglycemics only; and 170 (26.8%) receiving no pharmacologic treatment for diabetes. Patients on insulin reached the primary endpoint more frequently than patients on no pharmacologic treatment [61 (38%) vs 49 (29%) (HR 1.56, 95% CI 1.07-2.27, p = 0.022)] or oral hypoglycemics [61 (38%) vs 87 (29%) (HR 1.46, 1.05-2.03, p = 0.024)]. The primary endpoint occurred less frequently with edetate disodium based therapy versus placebo in patients on insulin [19 (26%) vs 42 (48%) (HR 0.42, 95% CI 0.25-0.74, log-rank p = 0.002)], marginally in patients on oral hypoglycemics [38 (25%) vs 49 (34%) (HR 0.66, 95% CI 0.43-1.01, log-rank p = 0.041)], and no significant difference in patients not treated with a pharmacologic therapy [23 (25%) vs 26 (34%) (HR 0.69, 95% CI 0.39-1.20, log-rank p = 0.225)]. The interaction between randomized intravenous treatment and type of diabetes therapy was not statistically significant (p = 0.203).
Edetate disodium treatment in stable, post-myocardial infarction patients with diabetes suggests that patients on insulin therapy at baseline may accrue the greatest benefit.
clinicaltrials.gov identifier: http://clinicaltrials.gov/ct2/show/NCT00044213?term=TACT&rank=7 identifier Trial to Assess Chelation Therapy (TACT), NCT00044213.

Citric acid-based bicarbonate haemodialysis (CIT-HD) has gained more clinical acceptance over the last few years in France and is a substitute for other acidifiers [e.g. acetic acid (CH3COOH) and hydrochloric acid (HCl)]. This trend was justified by several clinical benefits compared with CH3COOH as well as the desire to avoid the consequences of the corrosive action of HCl, but a nationwide clinical report raised concerns about the long-term safety of CIT-HD. The aim of this study was to assess the long-term effects of CIT-HD exposure on patient outcomes in western France.
This is a population-based retrospective multicentre observational study performed in 1132 incident end-stage kidney disease patients in five sanitary territories in western France who started their renal replacement therapy after 1 January 2008 and followed up through 15 October 2018. Relevant data, collected prospectively with the same medical software, were anonymously aggregated for the purposes of the study. The primary goal of this study was to investigate the effects of citrate exposure on all-cause mortality. To provide a control group to CIT-HD one, propensity score matching (PSM) at 2:1 was performed in two steps: the first analysis was intended to be exploratory, comparing patients who received citrate ≤80% of the time (CIT-HD ≤80) versus those who received citrate >80% of the time (CIT-HD >80), while the second analysis was intended to be explanatory in comparing patients with 0% (CIT-HD0) versus 100% citrate time exposure (CIT-HD100).
After PSM, in the exploratory part of the analysis, 432 CIT-HD ≤80 patients were compared with 216 CIT-HD >80 patients and no difference was found for all-cause mortality using the Kaplan-Meier model (log-rank 0.97), univariate Cox regression analysis {hazard ratio [HR] 1.01 [95% confidence interval (CI) 0.71-1.40]} and multivariate Cox regression analysis [HR 1.11 (95% CI 0.76-1.61)] when adjusted for nine variables with clinical pertinence and high statistical relevance in the univariate analysis. In the explanatory part of the analysis, 316 CIT-HD0 patients were then compared with 158 CIT-HD100 patients and no difference was found using the Kaplan-Meier model (log-rank 0.06), univariate Cox regression analysis [HR 0.69 (95% CI 0.47-1.03)] and multivariate Cox regression analysis [HR 0.87 (95% CI 0.57-1.33)] when adjusted for seven variables with clinical pertinence and high statistical relevance in the univariate analysis.
Findings of this study support the notion that CIT-HD exposure ≤6 years has no significant effect on all-cause mortality in HD patients. This finding remains true for patients receiving high-volume online haemodiafiltration, a modality most frequently prescribed in this cohort.

BACKGROUND: Accurate measurement of renal function is important: however, radiolabelled gold standard measurement of GFR is highly expensive and can only be used on a very limited scale. We aim to compare the performance of Modification of Diet in Renal Disease (MDRD) and Chronic Kidney Disease-Epidemiology Collaboration (CKD-EPI) equations in the multi-ethnic population attending University Malaya Medical Centre (UMMC).
METHODS: This is a cross-sectional study recruiting patients, who attend UMMC Nephrology clinics on voluntary basis. 51-Chromium EDTA (51Cr-EDTA) plasma level was used to measure the reference GFR. The serum creatinine was determined by IDMS reference modified Jaffe kinetic assay (CrJaffe). The predictive capabilities of MDRD and CKD-EPI based equations were calculated. Data was analysed using SPSS version 20 and correlation, bias, precision and accuracy were determined.
RESULTS: A total of 113 subjects with mean age of 58.12 ± 14.76 years and BMI of 25.99 ± 4.29 kg/m2 were recruited. The mean reference GFR was 66.98 ± 40.65 ml/min/1.73m2, while the estimated GFR based on MDRD and CKD-EPI formula were 62.17 ± 40.40, and 60.44 ± 34.59, respectively. Both MDRD and CKD-EPI were well-correlated with reference GFR (0.806 and 0.867 respectively) and statistically significant with p < 0.001. In the overall cohort, although MDRD had smaller bias than CKD-EPI (4.81 vs. 6.54), CKD-EPI was more precise (25.22 vs. 20.29) with higher accuracy within 30% of measured GFR (79.65 vs. 86.73%).
CONCLUSIONS: The CKD-EPI equation appeared to be more precise and accurate than the MDRD equation in estimating GFR in our cohort of multi-ethnic populations in Malaysia.

Objective: To investigate the optimal strategy for immunohistochemical (IHC) staining in bone metastasis specimens from breast cancer. Methods: Twenty-eight bone metastases specimens from breast cancers were divided into three groups and subjected to different decalcifying agents (group A-10% nitrate, group B-EDTA decalcification, and group C-imported decalcifying solution RapidCal). The effects of those on HE and IHC staining for Ki-67, ER, PR, GATA3, RANK, RANKL, HER2 and HER2 FISH results were assessed. Results: There were no significant differences among three groups in HE morphology and IHC staining. Antigen content in the RapidCal group were all intact; the EDTA group showed a similar staining rate, which was better than the nitrate group (P<0.05). Nitrate group showed marked reduction in nuclear Ki-67 staining, but the loss of cytoplasmic antigens (RANK, RANKL) was less than cell membrane antigen (HER2). For FISH, the RapidCal group and EDTA group showed same results, concordant with IHC staining results. The expression of HER2 protein in the nitric acid group was significantly decreased and chromosome 17 labelling was lost (P<0.05). Conclusions: RapidCal treated bone metastases specimens from breast cancer show excellent sample quality in morphological, IHC and FISH results compared with traditional decalcifying agents. Owing to the longer time of EDTA decalcification, the new decalcifying agent RapidCal plays an important role in quality control and clinical application.
目的： 探讨硝酸、乙二胺四乙酸(EDTA)和RapidCal三种不同脱钙液在乳腺癌骨转移标本的免疫组织化学和HER2荧光原位杂交(FISH)检测中的表现。 方法： 选取28例乳腺癌骨转移标本，建立统一的前处理方案，分别用不同的脱钙液(10%硝酸、10%EDTA、RapidCal脱钙液)进行分组脱钙，观察HE染色和Ki-67、雌激素受体(ER)、孕激素受体(PR)、GATA3、核因子κB受体活化因子(RANK)、核因子κB受体活化因子配体(RANKL)、HER2等免疫组织化学检测及HER2 FISH结果，并进行比较及评估。 结果： HE染色结果表明三组形态学无明显差异。RapidCal组对免疫组织化学各类定位的抗原保存均完好，具有和标准脱钙液EDTA相似的染色效果明显优于硝酸组(P<0.05)。硝酸组核计数缺失严重，Ki-67几乎为0，胞质抗原(RANK、RANKL)及胞膜抗原(HER2)丢失幅度小于核抗原。RapidCal组与EDTA组FISH结果一致，且与HER2免疫组织化学结果相符合，而硝酸组HER2蛋白表达信号明显下降，第17号染色体信号缺失(P<0.05)。 结论： 硝酸脱钙液处理后的标本染色效果较差，新型进口脱钙剂RapidCal和EDTA脱钙液处理的乳腺癌骨转移标本，在形态学、常用免疫组织化学和FISH的应用上表现出优秀的标本质量，但由于EDTA脱钙液脱钙时间过长，使用新型进口脱钙剂RapidCal将有利于质量控制及临床推广。.

Although citrate dialysate (CiDi) is regarded to be safe, dialysis modalities using higher dialysate volumes, like haemodiafiltration (HDF), may expose patients to higher citrate load and thus increase the risk of complications. We investigated the residual risk of CiDi compared with standard dialysate (StDi) in patients on different dialysis modalities and its effect on dialysis dose.
In a multicentre randomized crossover study, 92 dialysis patients (HDF post-dilution: n = 44, HDF pre-dilution: n = 26, haemodialysis: n = 25) were treated for 4 weeks with each dialysate (StDi and CiDi). Hypocalcaemia (ionized calcium ≤0.9 mmol/L), alkalosis (pH ≥7.55), post-treatment bicarbonate ≥32 mmol/L, pre-treatment bicarbonate ≥27 mmol/L, intra-dialytic events (IEs) and adverse events (AEs) between dialysis sessions were investigated as primary end points. The secondary objective was dialysis efficacy, i.e. dose and removal ratios of urea, creatinine, phosphate and β-2-microglobulin.
Post-dialysis overcorrection of bicarbonate (>32 mmol/L) was less frequent with CiDi (P = 0.008). Other predefined calcium and acid-base disturbances did not vary. There was no significant difference in IE. However, more patients developed AEs such as fatigue, muscle spasms or pain using CiDi (StDi: 41 versus CiDi: 55 patients, P = 0.02), particularly in the first 2 weeks of exposure. Dialysis efficacy was comparable with both dialysates.
It can be confirmed that CiDi is not associated with the development of severe calcium and acid-base disorders, even when dialysis modalities with higher citrate loads are used. However, a refinement of the CiDi composition to minimize AEs is necessary.

OBJECTIVE: Patients with liver failure requiring dialysis are at increased risk for citrate accumulation during sustained low-efficiency dialysis (SLED). The aim of this study was to evaluate the feasibilty of citrate SLED in critical ill patients with liver failure and investigate predictive parameters regarding citrate accumulation.
METHODS: This is a prospective study in 24 medical intensive care unit patients with liver failure and a total of 43 SLED runs (maximum of 3 runs per patient) using citrate anticoagulation. Liver function was characterized before SLED using not only laboratory parameters but also determination of the plasma disappearance rate of indocyanine green. In addition, blood gas parameters as well total calcium and citrate in serum were measured at baseline and defined time points during SLED.
RESULTS: Accumulation of citrate could be observed in all SLED runs, which were nearly normalized until the end of SLED and 24 hours after SLED, respectively. However, the critical threshold of total calcium/ionized calcium on ratio of greater than 2.5 was exceeded in only 1 patient. Equalization of initial metabolic acidosis was possible without major disturbances of acid base and electrolyte status. Liver function parameters showed poor predicitve capabilities regarding citrate accumulation.
CONCLUSIONS: Despite substantial accumulation of citrate in serum, SLED is save and feasible in patients with liver failure using a citrate anticoagulation. Careful monitoring of electrolytes and acid base status is mandatory to ensure patient safety.

BACKGROUND: The National Institutes of Health.funded Trial to Assess Chelation Therapy (TACT) randomized 1708 stablecoronary disease patients aged .50 years who were .6 months post.myocardial infarction (2003.2010) to 40 infusions ofa multicomponent EDTA chelation solution or placebo. Chelation reduced the primary composite end point of mortality,recurrent myocardial infarction, stroke, coronary revascularization, or hospitalization for angina (hazard ratio, 0.82; 95%confidence interval, 0.69.0.99; P=0.035).
RESULTS: In a randomly selected subset of 911 patients, we prospectively collected a battery of quality-of-life(QOL) instruments at baseline and at 6, 12, and 24 months after randomization. The prespecified primary QOL measures were the Duke Activity Status Index (Table I in the Data Supplement) and the Medical Outcomes Study Short-Form 36 Mental Health Inventory-5. All comparisons were by intention to treat. Baseline clinical and QOL variables were well balanced in the 451 patients randomized to chelation and in the 460 patients randomized to placebo. The Duke Activity Status Index improved in both groups during the first 6 months of therapy, but we found no evidence for a treatment-related difference (mean difference [chelation.placebo] during follow-up, 0.9 [95% confidence interval, .0.7 to 2.6; P=0.27]).There was no statistically significant evidence of a treatment-related difference in the Mental Health Inventory-5 during follow-up (mean difference, 1.0; 95% confidence interval, .0.1 to 2.0; P=0.08). None of the secondary QOL measures showed a consistent treatment-related difference.
CONCLUSIONS: In stable, predominantly asymptomatic coronary disease patients with a history of myocardial infarction,EDTA chelation therapy did not have a detectable effect on QOL during 2 years of follow-up.
BACKGROUND: URL: http://clinicaltrials.gov. Unique identifier: NCT00044213.