A case report of mediastinal parathyroid carcinoma in a chronic kidney disease patient: Addressing management conundrum

Parathyroid carcinoma is a rare malignancy; and it is rarer to find one located in an ectopic location. Ectopic parathyroid glands are a reported cause of failed primary surgery for hyperparathyroidism. We report here a 73-year-old male who previously had parathyroidectomy for primary hyperparathyroidism but then had recurrence of his symptoms with a diagnosis of a mediastinal parathyroid carcinoma on further evaluation. This presentation of complicated mediastinal parathyroid carcinoma posed significant diagnostic and management challenges due to comorbid stage IV chronic kidney disease (CKD). Secondly, due to the same comorbid condition, a more aggressive calcimimetic regimen could not be undertaken due to the risk of renal dysfunction with potential progression to dialysis status. Thirdly, he was a high-risk surgical candidate due to significant cardiovascular risks. Ideally, open surgical intervention would be recommended but due to the associated risks, he was managed with robotic-assisted thoracoscopic surgery. He subsequently developed hypocalcemia which normalized with supplemental calcium at follow-up.

Contemporary review of management techniques for cephalic arch stenosis in hemodialysis

The type of hemodialysis access and its preservation impact the quality of life and survival of patients undergoing hemodialysis. Vascular access complications are among the top causes of morbidity, hospitalization, and catheter use, with significant economic burden. Poor maturation and stenosis continue to be key impediments to upper arm arteriovenous fistula feasibility. Cephalic arch is a common location for vascular access dysfunction due to its distinctive anatomy, complex valves, and biochemical alterations attributable to renal failure. Understanding cephalic arch stenosis is critical due to its high prevalence and treatment failure. The appropriate management option is highly debatable and mostly dependent on patient characteristics and interventionist's preference. Current options include, percutaneous transluminal balloon angioplasty, stent grafts, bare metal stents, cutting balloon angioplasty, endovascular banding, and surgical procedures. This article discusses the etiologies of cephalic arch stenosis as well as currents trends in management including endovascular and surgical options.

Central vein stenosis in hemodialysis vascular access: clinical manifestations and contemporary management strategies

Central venous stenosis is a significant and frequently encountered problem in managing hemodialysis (HD) patients. Venous hypertension, often accompanied by severe symptoms, undermines the integrity of the hemodialysis access circuit. In central venous stenosis, dialysis through an arteriovenous fistula is usually inefficient, with high recirculation rates and prolonged bleeding after dialysis. Central vein stenosis is a known complication of indwelling intravascular and cardiac devices, such as peripherally inserted central catheters, long-term cuffed hemodialysis catheters, and pacemaker wires. Hence, preventing this challenging condition requires minimization of central venous catheter use. Endovascular interventions are the primary approach for treating central vein stenosis. Percutaneous angioplasty and stent placement may reestablish vascular function in cases of elastic and recurrent lesions. Currently, there is no consensus on the optimal treatment, as existing management approaches have a wide range of patency rates.

Pathophysiological concepts and screening of cardiovascular disease in dialysis patients

Dialysis patients experience 10-20 times higher cardiovascular mortality than the general population. The high burden of both conventional and nontraditional risk factors attributable to loss of renal function can explain higher rates of cardiovascular disease (CVD) morbidity and death among dialysis patients. As renal function declines, uremic toxins accumulate in the blood and disrupt cell function, causing cardiovascular damage. Hemodialysis patients have many cardiovascular complications, including sudden cardiac death. Peritoneal dialysis puts dialysis patients with end-stage renal disease at increased risk of CVD complications and emergency hospitalization. The current standard of care in this population is based on observational data, which has a high potential for bias due to the paucity of dedicated randomized clinical trials. Furthermore, guidelines lack specific guidelines for these patients, often inferring them from non-dialysis patient trials. A crucial step in the prevention and treatment of CVD would be to gain better knowledge of the influence of these predisposing risk factors. This review highlights the current evidence regarding the influence of advanced chronic disease on the cardiovascular system in patients undergoing renal dialysis.

Management of diabetic kidney disease: where do we stand?: A narrative review

Diabetic kidney disease is the leading cause of chronic kidney disease and end-stage renal disease. The pathogenesis and risk factors for the development of diabetic kidney disease are complex and multifaceted, resulting in glomerular hypertrophy, tubulointerstitial inflammation, and fibrosis. The clinical staging progresses over 5 stages from early hyperfiltration to overt nephropathy. Primary prevention like glycaemic control, control of blood pressure, treatment of dyslipidemia and lifestyle modifications have shown promising benefits. Despite widespread research, very few drugs are available to retard disease progression. More literature and research are needed to fill these lacunae. We carried out a literature search focusing on newer updates in diabetic kidney disease pathophysiology, diagnosis and management using a PubMed search through the National library of medicine using keywords "Diabetic kidney disease," and "Diabetic nephropathy" till the year 2022. We have summarized the relevant information from those articles.

Abstract 20: Effect of Dietary Sodium Reduction in Chronic Kidney Disease Patients With Albuminuria: Results of a Randomized Trial

Introduction: Albuminuria, an early marker of kidney damage, is a risk factor for chronic kidney disease (CKD) progression, cardiovascular disease (CVD), and death. Dietary sodium is a risk factor for elevated blood pressure, CVD, and all cause-mortality. It is particularly important in patients with CKD due to increased salt-sensitivity. It is unclear if dietary sodium reduction is associated with reduced albuminuria.

Hypothesis: A low sodium diet will reduce albuminuria in patients with CKD.

Methods: The Sodium Lowering and Urinary Protein Reduction (SUPER) Trial was a randomized, parallel trial testing the effect of a 24-week dietary sodium reduction intervention compared to usual diet on albuminuria in 151 CKD patients with albuminuria. Participants were eligible if they had an estimated glomerular filtration rate (eGFR) of 30-90 mL/min/1.73 m 2 and an albumin-to-creatinine ratio (ACR) of 30-1,500 mg/g. Intervention group participants received a dietician-led behavioral change intervention targeting sodium intake <2,300 mg/day and those in the control group received no dietary intervention. Twenty-four hour urine samples and dietary recalls, blood pressure, weight, and questionnaire data was collected at baseline, 12 weeks and 24 weeks. Mixed effects models were used to examine the intervention effect.

Results: Study participants were an average of 65.6 years old, 72% African American, and 48% women. Median baseline ACR was 180.3 mg/g in the intervention and 157.4 mg/g in the control group, respectively. Urinary sodium excretion was reduced by 15.5% and 0.0% in the intervention and control groups, respectively. Results for the primary and key secondary outcomes are presented in the Table.

Conclusions: The dietician-led dietary sodium reduction intervention succeeded in significantly reducing dietary sodium and BP in patients with CKD and albuminuria. However, no significant differences were observed in ACR, albuminuria, or eGFR between treatment groups.

Systematic oral hydration with water is similar to parenteral hydration for prevention of contrast-induced nephropathy: an updated meta-analysis of randomised clinical data

Background

Contrast-induced nephropathy (CIN) is the third most common cause of hospital-acquired kidney injury and is related to increased long-term morbidity and mortality. Adequate intravenous (IV) hydration has been demonstrated to lessen its occurrence. Oral (PO) hydration with water is inexpensive and readily available but its role for CIN prevention is yet to be determined.

Methods

PubMed, EMBASE and the Cochrane Central register of controlled trials (CENTRAL) databases were searched until April 2015 and studies were selected using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist. All randomised clinical trials with head-to-head comparison between PO and IV hydration were included.

Results

A total of 5 studies with 477 patients were included in the analysis, 255 of those receiving PO water. The incidence of CIN was statistically similar in the IV and PO arms (7.7% and 8.2%, respectively; relative risk 0.97; 95% CI 0.36 to 2.94; p=0.95). The incidence of CIN was statistically similar in the IV and PO arms in patients with chronic kidney disease and with normal renal function. Rise in creatinine at 48–72 h was lower in the PO hydration group compared with IV hydration (pooled standard mean difference 0.04; 95% CI 0.03 to 0.06; p<0.001; I²=62%).

Conclusions

Our meta-analysis shows that systematic PO hydration with water is at least as effective as IV hydration with saline to prevent CIN. PO hydration is cheaper and more easily administered than IV hydration, thus making it more attractive and just as effective.

Trimetazidine Decreases Risk of Contrast-Induced Nephropathy in Patients With Chronic Kidney Disease

Objectives:

We sought to synthesize and analyze the available data from randomized controlled trials (RCTs) for trimetazidine (TMZ) in the prevention of contrast-induced nephropathy (CIN).

Background:

Contrast-induced nephropathy after coronary angiography is associated with poor outcomes. Trimetazidine is an anti-ischemic drug that might reduce incidence of CIN, but current data are inconclusive.

Methods:

We searched MEDLINE/PubMed, EMBASE, Scopus, Cochrane Library, Web of Science, and ScienceDirect electronic databases for RCTs comparing intravenous hydration with normal saline (NS) and/or N-acetyl cysteine (NAC) versus TMZ plus NS ± NAC for prevention of CIN. We used RevMan 5.2 for statistical analysis with the fixed effects model.

Results:

Of the 808 studies, 3 RCTs met criteria with 290 patients in the TMZ plus NS ± NAC group and 292 patients in the NS ± NAC group. The mean age of patients was 59.5 years, and baseline serum creatinine ranged from 1.3 to 2 mg/dL. Trimetazidine significantly reduced the incidence of CIN by 11% (risk difference 0.11; 95% confidence interval, 0.16-0.06; P < .01). There was no significant heterogeneity between the studies (I2 statistic = 0). The number needed to treat to prevent 1 episode of CIN was 9.

Conclusions:

The addition of TMZ to NS ± NAC significantly decreased the incidence of CIN in patients undergoing coronary angiography. In conclusion, TMZ could be considered as a potential tool for prevention of CIN in patients with renal dysfunction.

Long-term outcome of ketoconazole and tacrolimus co-administration in kidney transplant patients

AIM: To study the long-term outcome of ketoconazole and tacrolimus combination in kidney transplant recipients.

METHODS: From 2006 to 2010, ketoconazole was given in 199 patients and was continued for at least 1 year or until graft failure (Group 1), while 149 patients did not receive any ketoconazole (Group 2). A combination of tacrolimus, mycophenolate and steroid was used as maintenance therapy. High risk patients received basiliximab induction.

RESULTS: Basic demographic data was similar between the 2 groups. The 5-year cumulative incidence of biopsy-confirmed and clinically-treated acute rejection was significantly higher in Group 1 than in Group 2 (34% vs 18%, P = 0.01). The 5-year Kaplan-Meier estimated graft survival (74.3% vs 76.4%, P = 0.58) and patient survival (87.8% vs 87.5%, P = 0.93) were not different between the 2 groups. Multivariable analyses identified ketoconazole usage as an independent risk of acute rejection (HR = 2.33, 95%CI: 1.33-4.07; P = 0.003) while tacrolimus dose in the 2^nd month was protective (HR = 0.89, 95%CI: 0.75-0.96; P = 0.041).

CONCLUSION: Co-administration of ketoconazole and tacrolimus is associated with significantly higher incidence of acute rejection in kidney transplant recipients.

Essential concept of transplant immunology for clinical practice

Our understanding of transplant immunology has advanced from gross allograft rejection to cellular response and to current molecular level. More sensitive assays have been developed to characterize patient sensitization and to detect pre-existing donor-specific antibodies (DSA) in pre-transplant crossmatch. After a transplant, pre-existing or de novo DSA are increasingly monitored to guide clinical management. Therefore, it is important for clinicians to understand the basic concepts and key components of transplant immunology as well as be familiarized with the modern immunological techniques used in kidney transplantation.

"Perilous pearl"--papillary fibroelastoma of aortic valve: a case report and literature review

Papillary fibroelastomas of the heart valves are benign, slow-growing, rare tumors of the heart. These lesions are primarily responsible for embolic events that can clinically manifest with neurological and cardiovascular symptoms. Early diagnosis is very important, as surgical excision of these tumors can prevent cerebrovascular and cardiovascular complications. The case of a 60-year-old man who presented with a neurological deficit caused by a papillary fibroelastoma of the noncoronary cusp of the aortic valve is described. Diagnosis was made by transesophageal echocardiogram, and the tumor was resected surgically.

Cardioprotection by Sulfaphenazole, a Cytochrome P450 Inhibitor: Mitigation of Ischemia-Reperfusion Injury by Scavenging of Reactive Oxygen Species

Cytochrome P450 (P450) enzymes play a significant role in promoting myocardial ischemia-reperfusion (I/R) injury. CYP2C9, an isoform of P450, is known to generate superoxide radicals in the reperfused heart. Sulfaphenazole (SPZ), a CYP2C9 inhibitor, has been shown to decrease I/R injury; however, the mechanism of cardioprotection by SPZ is not well elucidated. The objective of this study was to test whether SPZ mitigates myocardial I/R injury by scavenging reactive oxygen species (ROS). Isolated rat hearts were subjected to 30 min of global ischemia followed by 45 min of reperfusion. Hearts were perfused with SPZ and/or N(omega)-nitro-L-arginine methylester (L-NAME). Coronary flow (CF), left-ventricular developed pressure (LVDP), and rate-pressure product (RPP) were monitored. Superoxide and nitric oxide (NO) generation in the reperfused tissue was determined using fluorescence methods. Myocardial infarct size was measured using triphenyltetrazolium chloride staining. The SPZ-treated group showed a significant recovery of cardiac function compared with the untreated I/R group (CF, 53 versus 45%; LVDP, 48 versus 22%; RPP, 51 versus 20%). The infarct size was significantly reduced in the SPZ-treated group (15%) compared with the I/R control (42%). Coadministration of L-NAME with SPZ significantly attenuated the beneficial effects of SPZ. In addition, SPZ treatment showed significantly decreased superoxide levels and enhanced NO bioavailability in the reperfused heart. In conclusion, the protective effect of SPZ against I/R-mediated myocardial damage appears to be due to a reduction in the superoxide level caused by its inhibition of CYP2C9, as well as scavenging of oxygen free radicals generated in the reperfused heart.

Prevention of Postischemic Myocardial Reperfusion Injury by the Combined Treatment of NCX-4016 and Tempol

Nitric oxide (NO) plays a protective role in myocardial ischemia-reperfusion (I/R) injury. However, the concomitant production of superoxide and other reactive oxygen species (ROS) during I/R may diminish the bioavailability of NO and hence compromise the beneficial effects. The objective of this study was to investigate the protective effect of the coadministration of NCX-4016 [2-(acetyloxy)benzoic acid 3-(nitrooxymethyl)phenyl ester] (an NO donor) with antioxidants Tempol, superoxide dismutase (SOD), or urate on I/R injury. Isolated rat hearts, perfused with Krebs-Henseleit buffer, were subjected to 30 minutes of global ischemia, followed by 45 minutes of reperfusion. Before the induction of ischemia, the hearts were infused for 1 minute with NCX-4016 (100 microM) either alone or in combination with Tempol (100 microM), SOD (200 U/mL), or urate (100 microM). Hearts pretreated with NCX-4016 showed a significantly enhanced recovery of function and decreased infarct size and LDH/CK release compared with the controls. However, treatment of hearts with NCX-4016 + Tempol, SOD, or urate showed a significantly enhanced recovery of heart function compared with NCX-4016 alone. The treatment of hearts with NCX-4016 + Tempol showed significantly enhanced NO generation and decreased ROS and dityrosine (a marker of peroxynitrite) formation. In conclusion, NCX-4016 in combination with Tempol demonstrated significant cardioprotection and, thus, may offer a novel therapeutic strategy to prevent I/R-mediated myocardial injury.