Skin lesions in a man with end-stage renal disease.

ABSTRACT: Calciphylaxis is an uncommon condition most often seen in patients with end-stage renal disease. It is easily mistaken for other more common conditions and requires a high level of suspicion to make a timely diagnosis. Although various treatments such as IV sodium thiosulfate and bisphosphonates have been used for management, calciphylaxis remains a condition with a high mortality that requires an interdisciplinary approach for optimal management.

Dietary citrate supplementation enhances longevity, metabolic health, and memory performance through promoting ketogenesis.

Citrate is an essential substrate for energy metabolism that plays critical roles in regulating cell growth and survival. However, the action of citrate in regulating metabolism, cognition, and aging at the organismal level remains poorly understood. Here, we report that dietary supplementation with citrate significantly reduces energy status and extends lifespan in Drosophila melanogaster. Our genetic studies in fruit flies implicate a molecular mechanism associated with AMP-activated protein kinase (AMPK), target of rapamycin (TOR), and ketogenesis. Mice fed a high-fat diet that supplemented with citrate or the ketone body ß-hydroxybutyrate (ßOHB) also display improved metabolic health and memory. These results suggest that dietary citrate supplementation may prove to be a useful intervention in the future treatment of age-related dysfunction.

Simplified, Readily Available Method for the Treatment of Band Keratopathy With Ethylenediaminetetraacetic Acid.

PURPOSE: To compare 3 methods for creating ethylenediaminetetraacetic acid (EDTA) solution using readily available Vacutainer tubes for the treatment of band keratopathy. METHODS: All 3 protocols used commercially available Vacutainer blood collection tubes coated with K2EDTA. An osmometer was used to measure and compare the concentration of EDTA created using 3 different protocols. The time required for preparation of the solution was measured and compared to evaluate its efficiency for everyday clinical use. In addition, volume of EDTA solution obtained was measured for method 1. The most promising protocol for clinical use was then used for treatment of a series of patients. RESULTS: Average osmolarity was 532, 285, and 422 for methods 1, 2, and 3, respectively (ANOVA P < 0.01, all Tukey honestly significant difference P < 0.01). For the respective mixtures, average concentration was 65, 35, and 52 mg/mL, and average time to create solution was 189, 38, and 83 seconds (ANOVA P < 0.01, all Tukey honestly significant difference P < 0.01). The most promising, method 3, was found to be safe and effective in removing calcium from the corneal stroma in a series of 5 patients with 6 eyes treated. It also yielded 25% more solution for clinical use than method 1. CONCLUSIONS: Method 3 using a single 10-mL Vacutainer tube with 18 mg of K2-EDTA had the best balance of effective concentration of EDTA, time to preparation, and simplicity of methodology, when compared with previously published methods 1 and 2. It also yielded a greater final volume of solution.

BAPTA, a calcium chelator, neuroprotects injured neurons in vitro and promotes motor recovery after spinal cord transection in vivo.

AIM: Despite animal evidence of a role of calcium in the pathogenesis of spinal cord injury, several studies conducted in the past found calcium blockade ineffective. However, those studies involved oral or parenteral administration of Ca++ antagonists. We hypothesized that Ca++ blockade might be effective with local/immediate application (LIA) at the time of neural injury. METHODS: In this study, we assessed the effects of LIA of BAPTA (1,2-bis (o-aminophenoxy) ethane-N, N, N', N'-tetraacetic acid), a cell-permeable highly selective Ca++ chelator, after spinal cord transection (SCT) in mice over 4 weeks. Effects of BAPTA were assessed behaviorally and with immunohistochemistry. Concurrently, BAPTA was submitted for the first time to multimodality assessment in an in vitro model of neural damage as a possible spinal neuroprotectant. RESULTS: We demonstrate that BAPTA alleviates neuronal apoptosis caused by physical damage by inhibition of neuronal apoptosis and reactive oxygen species (ROS) generation. This translates to enhanced preservation of electrophysiological function and superior behavioral recovery. CONCLUSION: This study shows for the first time that local/immediate application of Ca++ chelator BAPTA is strongly neuroprotective after severe spinal cord injury.

Calciprotein Particles: Balancing Mineral Homeostasis and Vascular Pathology.

[Figure: see text].

Possible differential benefits of edetate disodium in post-myocardial infarction patients with diabetes treated with different hypoglycemic strategies in the Trial to Assess Chelation Therapy (TACT).

BACKGROUND: 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. METHODS: 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. RESULTS: 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). CONCLUSIONS: Edetate disodium treatment in stable, post-myocardial infarction patients with diabetes suggests that patients on insulin therapy at baseline may accrue the greatest benefit. CLINICAL TRIAL REGISTRATION: clinicaltrials.gov identifier: http://clinicaltrials.gov/ct2/show/NCT00044213?term=TACT&rank=7 identifier Trial to Assess Chelation Therapy (TACT), NCT00044213.

Hexametaphosphate as a potential therapy for the dissolution and prevention of kidney stones.

The incidence of kidney stones is increasing worldwide, and recurrence is common (50% within 5 years). Citrate, the current gold standard therapy, which is usually given as potassium or sodium salts, is used because it raises urine pH and chelates calcium, the primary component of up to 94% of stones. In this study hexametaphosphate (HMP), a potent calcium chelator, was found to be 12 times more effective at dissolving calcium oxalate, the primary component of kidney stones, than citrate. HMP was also observed to be effective against other common kidney stone components, namely calcium phosphate and struvite (magnesium ammonium phosphate). Interestingly, HMP was capable of raising the zeta potential of calcium oxalate particles from -15.4 to -34.6 mV, which may prevent stone growth by aggregation, the most rapid growth mechanism, and thus avert occlusion. Notably, HMP was shown to be up to 16 times as effective as citrate at dissolving human kidney stones under simulated physiological conditions. It may thus be concluded that HMP is a promising potential therapy for calcium and struvite kidney stones.

Potential Role of Metal Chelation to Prevent the Cardiovascular Complications of Diabetes.

CONTEXT: For decades, there has been epidemiologic evidence linking chronic toxic metal exposure with cardiovascular disease, suggesting a therapeutic role for metal chelation. Given the lack of compelling scientific evidence, however, the indications for metal chelation were never clearly defined. To determine the safety and efficacy of chelation therapy, the National Institutes of Health funded the Trial to Assess Chelation Therapy (TACT). TACT was the first double-blind, randomized, controlled trial to demonstrate an improvement in cardiovascular outcomes with edetate disodium therapy in patients with prior myocardial infarction. The therapeutic benefit was striking among the prespecified subgroup of patients with diabetes. DESIGN: We review the published literature focusing on the atherogenic nature of diabetes, as well as available evidence from clinical trials, complete and in progress, of metal chelation with edetate disodium therapy in patients with diabetes. RESULTS: The TACT results support the concept that ubiquitous toxic metals such as lead and cadmium may be modifiable risk factors for cardiovascular disease, particularly in patients with diabetes. CONCLUSIONS: The purpose of this review is to discuss the potential mechanisms unifying the pathogenesis of atherogenic factors in diabetes with toxic metal exposure, and the potential role of metal chelation.

Citrate therapy for calcium phosphate stones.

PURPOSE OF REVIEW: Calcium phosphate (CaP) stones represent an increasingly encountered form of recurrent nephrolithiasis, but current prophylactic medical regimens are suboptimal. Although hypocitraturia is a well-described risk factor for CaP stones, strategies that enhance citrate excretion have not consistently been effective at reducing CaP saturation and stone recurrence. This review summarizes the role of citrate therapy in CaP nephrolithiasis. RECENT FINDINGS: Citrate in urine inhibits CaP stone formation through multiple mechanisms, including the formation of soluble citrate-calcium complexes, and inhibition of CaP nucleation, crystal growth and crystal aggregation. Recent in-vitro studies demonstrate that citrate delays CaP crystal growth through distinct inhibitory mechanisms that depend on supersaturation and citrate concentration. The impact of pharmacological provision of citrate on CaP saturation depends on the accompanying cation: Potassium citrate imparts a significant alkali load that enhances citraturia and reduces calciuria, but could worsen urine pH elevation. Conversely, citric acid administration results in minimal citraturia and alteration in CaP saturation. SUMMARY: Citrate, starting at very low urinary concentrations, can significantly retard CaP crystal growth in vitro through diverse mechanisms. Clinically, the net impact on CaP stone formation of providing an alkali load during pharmacological delivery of citrate into the urinary environment remains to be determined.

Lead Levels in the Eggs of a Chicken With Lead Toxicosis.

A 1.5-year-old Polish hen was presented with a history of watery droppings and poor vent tone. Results of diagnostic tests revealed blood lead at levels considered to be toxic. Chelation therapy was started with calcium ethylenediaminetetraacetate. The hen was laying eggs before, during, and after chelation therapy. Eggs were tested for the presence of lead by combining yolk and albumen together. Before chelation therapy, the level of lead in the egg tested was 14 µg. Two days after the end of chelation therapy, results of a second blood lead test revealed a drop to nontoxic levels. No lead was detected in the combined yolks and albumen of eggs collected 7-11 days after the end of chelation therapy. Four weeks after the end of chelation therapy, no lead was identified in the shells of tested eggs.

Strategies to Reduce Catheter-Related Bloodstream Infections in Pediatric Patients Receiving Home Parenteral Nutrition: The Efficacy of Taurolidine-Citrate Prophylactic-Locking.

BACKGROUND: Catheter-related bloodstream infections (CRBSIs) remain a major issue in patients who are receiving home parenteral nutrition (HPN). The aim of this interventional study was to assess the impact of a new strategy using taurolidine-citrate (T-C) prophylactic locks on the CRBSI rate in children with intestinal failure who are receiving HPN. METHODS: The rate of CRBSIs was monitored every calendar year in a prospective cohort of 195 children with intestinal failure. T-C locks were initiated from October 2011 in children with recurring CRBSIs (≥2 episodes per year). RESULTS: In the whole cohort, the median annual CRBSI rate per 1000 catheter days decreased significantly from 2.07 in 2008 to 2010 to 1.23 in 2012 to 2014 (P < .05). T-C locks were used in 40 patients. No adverse events were reported. In taurolidine-treated patients, the CRBSI rate per 1000 catheter days decreased from 4.16 to 0.25 (P < .0001). The cumulative percentage of patients free of CRBSI at 18 months was 92% (95% confidence interval [CI]: 71-98) on T-C lock vs 61% (95% CI: 49-72) in controls (P = .01). In multivariate analysis, factors associated with CRBSI were immune deficiency (adjusted hazard ratio 3.49; 95% CI: 1.01-12.17) and the young age of the parents (adjusted hazard ratio 4.79, 95% CI: 2.16-10.62), whereas T-C locks were protective (adjusted hazard ratio 0.22, 95% CI: 0.06-0.74). CONCLUSION: This study confirms the efficacy of T-C catheter locks in decreasing the incidence of CRBSIs in children with intestinal failure who are receiving HPN.

Amelioration of Endotoxin-Induced Inflammatory Toxic Response by a Metal Chelator in Rat Eyes.

Purpose: Metal ions play a key role in exacerbating toxicity associated with oxidative stress and inflammation. This study examines the effects of a formulation containing the metal chelator ethylenediaminetetraacetic acid (EDTA) and permeability enhancer methyl sulfonyl methane (MSM) on the early course of inflammation in endotoxin-induced uveitis (EIU). The proprietary MSM/EDTA formulation of Livionex, Inc., which was used for this study, is covered by several patents and pending patent applications. Methods: EIU was induced by using subcutaneous injection of lipopolysaccharide (LPS) into the thighs of Lewis rats. Treatment consisted of topical application to the eyes of either PBS or eye drops designated as ME that contain EDTA and MSM. Clinical signs of uveitis were monitored at 6 and 24 hours postinjection. Oxidative and inflammatory markers were evaluated by ELISA or immunohistochemistry. Results: Rats treated with ME showed fewer clinical signs of uveitis including reduced miosis, fibrinous exudates, and dilated blood vessels. The aqueous humor of treated rats contained fewer leukocytes, lower protein levels, and less PGE2. Formation of protein adducts with the lipid peroxidation end-product, 4-hydroxynonenal, expression of NF-κB, TNF-α, and MMP-9 were all reduced in rats treated with ME. Conclusions: Our results indicate that ME eye drops downregulate the ocular inflammatory response in LPS treated rats, suggesting that induction of EIU involves metal ions and chelation therapy with ME is a potential treatment for uveitis.

Systematic review of sodium thiosulfate in treating calciphylaxis in chronic kidney disease patients.

AIM: Calciphylaxis is a severe complication of advanced chronic kidney disease (CKD). Sodium thiosulphate (STS), an antioxidant and calcium chelating agent, has been used for the treatment of calciphylaxis. However, its efficacy and safety have not been systematically analysed and evaluated. METHODS: MEDLINE, EMBASE, and the Cochrane Library database were systematically searched for case report or cases series on use of STS for calciphylaxis published between July 1974 and October 2016. We extracted data on clinical characteristics, laboratory tests result and medication use. The effective treatment was defined as improvement in skin lesion cicatrisation or pain relief without death. Non-responding effects were defined as stable skin lesions without remission or exacerbation of the disease in patients who remained alive. All-cause mortality after STS treatment was defined as death due to exacerbations of calciphylaxis or other complications of advanced CKD. We compared the baseline parameters of the patients as well as the efficacy and mortality of the STS therapy between case report and multi-case reports. Statistical analyses were performed using SPSS 19. RESULTS: A total of 83 papers were screened, 45 of them (n = 358) met the inclusion criteria, including 36 case reports (n = 64) and nine multi-case reports (n = 294). The mean age of the patients with calciphylaxis was 58 ± 14 years (range 26-91 years). They were female predominant, accounting for 74.1%. Among the patients with calciphylaxis, 96.1% patients were on dialysis with median dialysis vintage of 44.5 months (range 24-84 months). STS was effective in 70.1% of patients, 37.6% patients died. The proportion of patients with sepsis was higher among those who received intravenous STS. There was no significant difference in efficacy between the different STS administration methods (P = 0.19). CONCLUSION: Although the study was unable to assess the efficacy of sodium thiosulphate alone in the treatment of calciphylaxis, it still reveals a promising role of STS as an effective therapy for calciphylaxis. Further prospective studies to define the optimal therapy for calciphylaxis are needed.

A novel pharmacodynamic assay to evaluate the effects of crystallization inhibitors on calcium phosphate crystallization in human plasma.

Cardiovascular calcification (CVC) is a progressive complication of chronic kidney disease and a predictor of CV events and mortality. The use of biomarkers to predict CV risk and activities of potential or current treatment drugs in these patients could have a crucial impact on therapeutic approaches. Our aim was to develop a novel assay for measurement of the rate of calcium phosphate crystallization in human plasma and provide a tool to evaluate the effects of crystallization inhibitors. The efficacy of inhibitors was determined by adding inhibitory compounds (polyphosphates, fetuin-A, sodium thiosulfate or citrate) to control samples. The assay was additionally validated for SNF472, an experimental formulation of phytate being developed for the treatment of calciphylaxis and CVC in patients with end-stage renal disease (ESRD) undergoing hemodialysis (HD). The method was repeatable and reproducible. The plasma crystallization rate was reduced up to 80% in a concentration-dependent manner following treatment with inhibitors in vitro, among which SNF472 was the most potent. This method appears beneficial in evaluating and discriminating between inhibitory activities of compounds such as polyphosphates on calcium phosphate crystallization, which present a novel therapeutic approach to treat CVC in ESRD patients.

Guanosine 5'-monophosphate-chelated calcium and iron feed additives maintains egg production and prevents Salmonella Gallinarum in experimentally infected layers.

We evaluated the effects of guanosine 5'-monophosphate (GMP)-chelated calcium and iron (CaFe-GMP) on health and egg quality in layers experimentally infected with Salmonella Gallinarum. In this study, a CaFe-GMP feed additive was added to a commercial layer feed and fed to layers over a four-week period. All were inoculated with Salmonella Gallinarum. Body weight, mortality, clinical symptoms, and poultry production including feed intake, egg production, egg loss, and feed conversion rate were observed, and Salmonella Gallinarum was re-isolated from the liver, spleen, and cecum of the layers. All tested internal organs for the CaFe-GMP additive group exhibited significantly lower re-isolation numbers of Salmonella Gallinarum and less severe pathological changes than those in the control group, indicating that the CaFe-GMP feed supplement induced bacterial clearance and increased resistance to Salmonella Gallinarum. Additionally, due to the inhibitory action of CaFe-GMP on the growth of Salmonella Gallinarum, the CaFe-GMP additive group exhibited better egg production, including a higher laying rate and fewer broken eggs. The results suggest that a 0.16% CaFe-GMP additive may help prevent salmonellosis in the poultry industry.

Renal stone clinic survey: calcium stone formers' self-declared understanding of and adherence to physician's recommendations.

Nothing is known about how well stone formers understand physician's explanations of stone formation, and a few data are available on adherence to provided recommendations. In this study, two groups of recurrent calcium stone formers (RCSFs) were compared. Group 1: 153 consecutive RCSF (118 men, 35 women) referred 1/2011-6/2014. At least 3 months after a 60-75 min consultation explaining metabolic evaluation and therapeutic measures, RCSF received a questionnaire by mail, regarding understanding of stone formation and adherence to therapeutic recommendations (diet, lifestyle, drug treatment). Response rate was 62 %. Group 2 (control): 81 consecutive RCSFs referred 7/2014-3/2016 (60 men, 21 women) were asked to answer the same questionnaire in the stone center while waiting for their follow-up consultation 3 months after starting prevention; response rate was 100 %. Alkali citrate was prescribed in 45 %. Answer sheets were analyzed anonymously, and frequencies of answers were compared by Chi-square test. RESULTS: 67 % (group 1) and 62 % (group 2) indicated >80 % understanding of the given information (NS). Over 80 % adherence to recommendations occurred in 26 and 30 % (NS). Most frequent changes in dietary/lifestyle habits were increases in calcium (93 vs. 89 %) and fluid intakes (81 vs. 78 %); lowering psychosocial stress (23 vs. 24 %) was least popular. Adherence to 100 % on 6-7 days/week was significantly more frequent for medication than for dietary/lifestyle interventions, both in group 1 (84 vs. 24 %, p < 0.001) and group 2 (91 vs. 28 %, p < 0.001). CONCLUSIONS: (1) results do not differ whether RCSFs are voluntarily participating by mail or asked to answer questionnaires in the stone clinic; (2) pathophysiologic explanations of stone disease are understood to >80 % by 2/3 of RCSFs; (3) after 3 months, perfect adherence to recommended treatment is more frequent on alkali citrate than on dietary/lifestyle measures; and (4) increasing calcium and fluid intake are the most popular dietary measures.

The effect of EDTA root conditioning on periodontal surgery outcome: A meta-analysis.

OBJECTIVE: Chemical root conditioning is a procedure to remove the smear layer, which influences periodontal healing. The purpose of this study was to determine the effect of using ethylenediaminetetraacetic acid (EDTA) as a root conditioning agent on periodontal surgery outcomes. METHOD AND MATERIALS: The databases searched from their earliest records to February 2015 included Pubmed, Embase, the Cochrane library, and ISI Web of Science. Quality assessment of the methodologies of all the included studies and data was performed with Review Manager software. Probing depth (PD) and clinical attachment level (CAL) were analyzed using inverse variance. RESULTS: The evaluation of the three articles that met the inclusion criteria showed that the differences between the EDTA groups and the control groups were not statistically significant (6 months PD: mean difference [MD] = -0.15 mm, Z = 1.09, P = .27; CAL: MD = 0.15 mm, Z = 0.89, P = .37). CONCLUSION: EDTA was not able to significantly improve the PD and CAL. A positive outcome of using EDTA as a root conditioning agent was not evident. Thus, future research should focus on EDTA in combination with other drugs or a better alternative drug to EDTA.

Epitope analysis of antidesmoglein 1 autoantibodies from patients with pemphigus foliaceus across different activity stages.

BACKGROUND: Pemphigus foliaceus (PF) and pemphigus vulgaris (PV) are closely related, but clinically distinct, autoimmune blistering diseases caused by autoantibodies against desmoglein (Dsg)1 and Dsg3, respectively. Using ethylenediaminetetraacetic acid (EDTA)-treated Dsg3 enzyme-linked immunosorbent assay (ELISA) we have shown that the proportion of anti-Dsg3 antibodies against calcium-dependent epitopes decreased upon shifting to the inactive phase in patients with PV. OBJECTIVES: To analyse the epitope profiles of anti-Dsg1 antibodies across the different activity stages of PF. METHODS: We evaluated five patients with PF who retained high serum levels of anti-Dsg1 antibodies in the inactive phase. Sera were obtained in both the active and inactive phases, and were analysed by EDTA-treated and exfoliative toxin-treated ELISAs. To map the epitopes of anti-Dsg1 antibodies, immunoprecipitation-immunoblotting was performed using a set of Dsg1/Dsg2 domain-swapped molecules. RESULTS: Anti-Dsg1 antibodies against the calcium-dependent epitopes of Dsg1 were the predominant antibodies in both the active and inactive phases. The proportion of anti-Dsg1 antibodies against the calcium-dependent epitopes did not change upon shifting to the inactive phase. The results of immunoprecipitation-immunoblotting showed that most of the anti-Dsg1 antibodies bound to the extracellular domains (EC)1-2 of Dsg1. CONCLUSIONS: In patients with PF, the calcium-dependent epitopes on EC1 and EC2 of Dsg1 contained definitively pathogenic and nonpathogenic epitopes. The disease activity might be differentially controlled by the antibodies between PF and PV depending on the presence or absence of the nonpathogenic epitope.