No additional benefit of prescribing a very low-protein diet in patients with advanced chronic kidney disease under regular nephrology care: a pragmatic, randomized, controlled trial

BACKGROUND

Whether a very low-protein diet supplemented with ketoanalogues (sVLPD), compared with a standard low-protein diet (LPD), improves outcomes in patients with chronic kidney disease (CKD) under stable nephrology care is undefined.

OBJECTIVES

To compare the effectiveness of sVLPD compared with LPD in patients regularly seen in tertiary nephrology care.

METHODS

Participants were patients with CKD stages 4-5, followed for at least 6 mo, randomly allocated to receive sVLPD or LPD [0.35 or 0.60 g/kg ideal body weight (IBW)/d, respectively], stratified by center and CKD stage. The primary outcome was time to renal death, defined as the first event between end-stage renal disease (ESRD) and all-cause mortality; secondary outcomes were the single components of the primary outcome, cardiovascular outcome, and nutritional status.

RESULTS

We analyzed 223 patients (sVLPD, n = 107; LPD, n = 116). Mean age was 64 y, 61% were male, and 35% had diabetes. Median protein intake (PI), which was 0.8 g/kg IBW/d at baseline in both groups, was 0.83 and 0.60 g/kg IBW/d in LPD and sVLPD, respectively, during the trial with a large decrease only in sVLPD (P = 0.011). During a median of 74.2 mo, we recorded 180 renal deaths (141 dialysis and 39 deaths before dialysis). Risk of renal death did not differ in sVLPD compared with LPD (HR: 1.17; 95% CI: 0.88, 1.57; P = 0.28). No difference was observed for ESRD (HR: 1.12; 95% CI: 0.81, 1.56; P = 0.51), mortality (HR: 0.95; 95% CI: 0.62, 1.45; P = 0.82), or time to fatal/nonfatal cardiovascular events (P = 0.2, log-rank test). After 36 mo, still active patients were 45 in sVLPD and 56 in LPD. No change of nutritional status emerged during the study in any arm.

CONCLUSIONS

This long-term pragmatic trial found that in patients with CKD under stable nephrology care, adherence to protein restriction is low. Prescribing sVLPD compared with standard LPD is safe but does not provide additional advantage to the kidney or patient survival.

Thromboembolic and Bleeding Risk in Atrial Fibrillation Patients with Chronic Kidney Disease: Role of Anticoagulation Therapy

Atrial fibrillation (AF) and chronic kidney disease (CKD) are strictly related; several independent risk factors of AF are often frequent in CKD patients. AF prevalence is very common among these patients, ranging between 15% and 20% in advanced stages of CKD. Moreover, the results of several studies showed that AF patients with end stage renal disease (ESRD) have a higher mortality rate than patients with preserved renal function due to an increased incidence of stroke and an unpredicted elevated hemorrhagic risk. Direct oral anticoagulants (DOACs) are currently contraindicated in patients with ESRD and vitamin K antagonists (VKAs), remaining the only drugs allowed, although they show numerous critical issues such as a narrow therapeutic window, increased tissue calcification and an unfavorable risk/benefit ratio with low stroke prevention effect and augmented risk of major bleeding. The purpose of this review is to shed light on the applications of DOAC therapy in CKD patients, especially in ESRD patients.

[Native kidney ultrasound in obstructive uropathy]

The term "obstructive uropathy" refers to the complex structural and functional changes following the interruption of normal urinary runoff, which can occur at every level of the urinary tract. Depending on its origin, duration and severity, urinary tract obstructions can be acute or chronic, mono or bilateral, partial or complete. The obstruction can be localized or extended to the entire pielo-caliceal system and/or homolateral urethra. The term "hydronephrosis" indicates the dilation of the pelvis detected through imaging techniques. Among these, ultrasound is considered the gold standard in the diagnosis of obstructive uropathy: it allows to distinguish three degrees of urinary tract dilation, depending on the extent of the dilation itself and the thickness of the parenchyma. Nephrologists are confronted daily with patients who experience kidney failure and must be able to quickly distinguish between chronic and acute and, in the latter case, to discern between issues of nephrological or urological competence. This short review aims at helping them deal with this very common scenario, through the use of ultrasound.

Kidney Disease in HIV Infection

Antiretroviral therapy (ART) has significantly improved life expectancy of infected subjects, generating a new epidemiological setting of people aging withHuman Immunodeficiency Virus (HIV). People living with HIV (PLWH), having longer life expectancy, now face several age-related conditions as well as side effects of long-term exposure of ART. Chronic kidney disease (CKD) is a common comorbidity in this population. CKD is a relentlessly progressive disease that may evolve toward end-stage renal disease (ESRD) and significantly affect quality of life and risk of death. Herein, we review current understanding of renal involvement in PLWH, mechanisms and risk factors for CKD as well as strategies for early recognition of renal dysfunction and best care of CKD.

[Laws regulating transplantation should express the contemporaneity. Questions to the constitutionalist Francesco Paolo Casavola and to the philosophers Remo Bodei and Aldo Masullo about the possibility deciding the destiny of one's own organs at the time one decides on how to die and on contacts between donor families and recipients.]

Transplantation represents modernity thus the laws regulating the procedure should be continuously renovated and remodeled in order to take full advantage of progress. The debate is about Law no. 219, December 22, 2017 and on Law no. 222, April 1, 1999. The quests are a) about the possibility to modify the first so that people deciding on how they want to die, may also decide about their willingness to allow the removal of their organs for transplantation and b) the possibility for donor families and recipients to have contacts after transplantation in the case both sides agree. Questions were emailed to the constitutionalist Francesco Paolo Casavola, immediate Past President of the National Committee for Bioethics, and to the philosophers Remo Bodei and Aldo Masullo. Their answers received by September 16, support the idea a) to include in the Law no. 219, 2017 the possibility to decide not only on the modality one wants to die but also on the possibility to allow his own organs to be removed for transplantation and b) to liberalize contacts between donor families and recipients when both side agree. For both changes there is enough evidence of their feasibility-necessity. The answers related to contacts between donor families and recipients support the decision of the National Committee for Bioethics on September 27, 2018. Professor Casavola also suggests that contacts should organized and supervised by the ethical committees of the hospitals where the transplantation procedure is accomplished.

Supplementation of Short-Chain Fatty Acid, Sodium Propionate, in Patients on Maintenance Hemodialysis: Beneficial Effects on Inflammatory Parameters and Gut-Derived Uremic Toxins, A Pilot Study (PLAN Study)

BACKGROUND

In end-stage renal disease (ESRD), gut-derived uremic toxins play a crucial role in the systemic inflammation and oxidative stress promoting the excess morbidity and mortality. The biochemical derangement is in part a consequence of an insufficient generation of short-chain fatty acids (SCFA) due to the dysbiosis of the gut and an insufficient consumption of the fermentable complex carbohydrates.

AIM OF THE STUDY

The primary end-point was to evaluate the potential efficacy of SCFA (specifically, sodium propionate (SP)) for patients on maintenance hemodialysis (MHD) on systemic inflammation. Secondary end-points included potential attenuation of oxidative stress markers, insulin resistance and production of gut-derived uremic toxins indoxyl sulfate and p-cresol sulfate, as well as health status after SP supplementation.

STUDY DESIGN

We performed a single-center non-randomized pilot study in 20 MHD patients. They received the food additive SP with a daily intake of 2 × 500 mg in the form of capsules for 12 weeks. Pre-dialysis blood samples were taken at the beginning, after six weeks and at the end of the administration period, as well as four weeks after withdrawal of the treatment.

RESULTS

The subjects revealed a significant decline of inflammatory parameters C-reactive protein (-46%), interleukin IL-2 (-27%) and IL-17 (-15%). The inflammatory parameters IL-6 and IFN-gamma showed a mild non-significant reduction and the anti-inflammatory cytokine IL-10 increased significantly (+71%). While the concentration of bacterial endotoxins and TNF-α remained unchanged, the gut-derived uremic toxins, indoxyl sulfate (-30%) and p-cresyl sulfate (-50%), revealed a significant decline. The SP supplementation reduced the parameters of oxidative stress malondialdehyde (-32%) and glutathione peroxidase activity (-28%). The serum insulin levels dropped by 30% and the HOMA-index by 32%. The reduction of inflammatory parameters was associated with a lowering of ferritin and a significant increase in transferrin saturation (TSAT). Four weeks after the end of the treatment phase, all improved parameters deteriorated again. Evaluation of the psycho-physical performance with the short form 36 (SF-36) questionnaire showed an enhancement in the self-reported physical functioning, general health, vitality and mental health. The SP supplementation was well tolerated and without important side effects. No patient had left the study due to intolerance to the medication. The SP supplementation in MHD patients reduced pro-inflammatory parameters and oxidative stress and improved insulin resistance and iron metabolism. Furthermore, SP effectively lowered the important gut-derived uremic toxins indoxyl and p-cresol sulfate. These improvements were associated with a better quality of life. Further controlled studies are required in a larger cohort to evaluate the clinical outcome.

[Protein carbamylation: what it is and why it concerns nephrologists]

Spontaneous urea dissociation in water solution is a prominent source of protein carbamylation in our body. Protein carbamylation is a well-known phenomenon since early seventies. Some years ago, much interest in the diagnostic power of carbamylated protein arouse. Recently the target of the researches focused on its potential cardiovascular pathogenicity. Some authors claimed that this could be a reason for higher cardiovascular mortality in uremic patients. Nutritional therapy, amino acids supplementation and intensive dialysis regimen are some of the therapeutic tools tested to lower the carbamylation burst in this population.

Ultrapure dialysis water obtained with additional ultrafilter may reduce inflammation in patients on hemodialysis

BACKGROUND

Patients on standard dialysis, in particular those on high-flux and high-efficiency dialysis, are exposed to hundreds of liters of dialysis-water per week. The quality of dialysis-water is a factor responsible for inflammation in dialysis patients. Inflammation is a potent trigger of atherosclerosis and a pathogenetic factor in anemia, increasing mortality and morbidity in dialysis patients. Current systems for water treatment do not completely eliminate bacteria and endotoxins. This prospective study tested whether improved dialysis-water purity by an additional ultrafilter can reduce inflammation and ameliorate hemoglobin levels, with a consequent reduction in erythropoietin-stimulating agents (ESA).

METHODS

An ultrafilter, composed of two serially positioned devices with polysulfone membranes of 2.0 and 1.0 m2, respectively, was positioned within the fluid pathway before the dialysis machine. Prevalent dialysis patients were assigned either to continue dialysis with conventional dialysis-water (control phase) or to initiate dialysis sessions with improved dialysis-water purity (study phase). After 6 months, patients were crossed over. Total study duration was 1 year. Routine chemistry, bacterial count, endotoxin levels in dialysis-water as well as blood levels of pro- and anti-inflammatory cytokines, human serum amyloid A, C-reactive protein and fraction 5 of complement were measured.

RESULTS

Thirty-two patients completed the study. Mean bacterial count was lower and endotoxin levels were absent in dialysis-water obtained with the ultrafilter. At the end of the study-phase, C-reactive protein and pro-inflammatory cytokines decreased while anti-inflammatory ones increased. Hemoglobin levels were improved with lower ESA doses.

CONCLUSIONS

An additional ultrafilter improved dialysis-water purity, reduced levels of inflammation markers, ameliorated hemoglobin concentration with reduced ESA doses. These results remain speculative but they may generate studies to assess whether improved dialysis-water quality with an ultrafilter can reduce inflammation and improve survival of dialysis patients.

The treatment of type 2 diabetes mellitus in patients with chronic kidney disease: What to expect from new oral hypoglycemic agents

Worldwide, an estimated 200 million people have chronic kidney disease (CKD), whose most common causes include hypertension, arteriosclerosis, and diabetes. About 40% of patients with diabetes develop CKD and intensive blood glucose control through pharmacological intervention can delay CKD progression. Standard therapies for the treatment of type 2 diabetes mellitus include metformin, sulfonylureas, meglitinides, thiazolidinediones, and insulin. While these drugs have an important role in the management of type 2 diabetes, only the thiazolidinedione pioglitazone can be used across the spectrum of CKD (stages 2-5) and without dose adjustment. Newer therapies, particularly dipeptidyl peptidase-IV inhibitors, glucagon-like peptide-1 receptor agonists, and sodium-glucose cotransporter-2 inhibitors, are increasingly being used in the treatment of type 2 diabetes; however, a major consideration is whether these newer therapies can also be used safely and effectively across the spectrum of renal impairment.

Carmelo Giordano (1930-2016): a giant in Nephrology

Carmelo Giordano (Carmine, Louis, Joseph Giordano) was born in Naples on August 23, 1930 in the house of Rafael and Anna Tirone He received the MD cum laude in 1954. He was Fellow and assistant to Professor Flaviano Magrassi and studied nephrology at the Peter Bent Brigham Hospital, University of Harvard in Boston, under the guidance of John P. Merrill (1958-1960). He was nominated Professor of Nephrology at the University Federico II, Naples in 1975 and Professor of Medicine at the Second University of Naples (1986-2002). The National Institutes of Health of the United States in Bethesda financed his research for more than 20 years. He started low protein alimentation (Giordano-Giovannetti diet according to Geoffrey M. Berlyne) with or without addition of amino acids and ketoacids and devised formula diets for CKD infants and children. He demonstrated that 85% of CKD patients receiving a 25 g protein diet were in positive nitrogen balance. Later he introduced the concept of energy load from dialysate in CAPD and the assessment of amino acid losses during hemodialysis and peritoneal dialysis. He also researched the minimum protein requirement under CAPD regimens. He synthesized, with Professor Renato Esposito, oxystarch and oycellulose and introduced the use of carbon at low temperature and its regeneration at 90°C. He introduced wearable and portable artificial kidneys. He died in Naples on May 12, 2016.

[Sudden cardiac death in patient with CKD]

Despite significant improvements in technology of dialysis delivery, cardiovascular disease remains the mayor cause of death in dialysis patients. Individuals with End Stage Renal Disease (ESRD( present an high incidence of coronary artery disease, arrhythmia and sudden cardiac death (SCD). This review summarizes the current available literature regarding the physiopathology, the risk factors and potential interventions to reduce the risk of SCD in dialysis patients, including medical therapy or defibrillators.

Correction of metabolic acidosis improves insulin resistance in chronic kidney disease

Background

Correction of metabolic acidosis (MA) with nutritional therapy or bicarbonate administration is widely used in chronic kidney disease (CKD) patients. However, it is unknown whether these interventions reduce insulin resistance (IR) in diabetic patients with CKD. We sought to evaluate the effect of MA correction on endogenous insulin action in diabetic type 2 (DM2) CKD patients.

Methods

A total of 145 CKD subjects (83 men e 62 women) with DM2 treated with oral antidiabetic drugs were included in the study and followed up to 1 year. All patients were randomly assigned 1:1 to either open-label (A) oral bicarbonate to achieve serum bicarbonate levels of 24–28 mmol/L (treatment group) or (B) no treatment (control group). The Homeostatic model assessment (HOMA) index was used to evaluate IR at study inception and conclusion. Parametric and non-parametric tests as well as linear regression were used.

Results

At baseline no differences in demographic and clinical characteristics between the two groups was observed. Average dose of bicarbonate in the treatment group was 0.7 ± 0.2 mmol/kg. Treated patients showed a better metabolic control as confirmed by lower insulin levels (13.4 ± 5.2 vs 19.9 ± 6.3; for treated and control subjects respectively; p < 0.001), Homa-IR (5.9[5.0-7.0] vs 6.3[5.3–8.2]; p = 0.01) and need for oral antidiabetic drugs. The serum bicarbonate and HOMA-IR relationship was non-linear and the largest HOMA-IR reduction was noted for serum bicarbonate levels between 24 and 28 mmol/l. Adjustment for confounders, suggests that serum bicarbonate rather than treatment drives the effect on HOMA-IR.

Conclusions

Serum bicarbonate is related to IR and the largest HOMA-IR reduction is noted for serum bicarbonate between 24 and 28 mmol/l. Treatment with bicarbonate influences IR. However, changes in serum bicarbonate explains the effect of treatment on HOMA index. Future efforts are required to validate these results in diabetic and non-diabetic CKD patients.

Trial registration

The trial was registered at www.clinicaltrial.gov (Use of Bicarbonate in Chronic Renal Insufficiency (UBI) study - NCT01640119)

Nutritional support in the tertiary care of patients affected by chronic renal insufficiency: report of a step-wise, personalized, pragmatic approach

Background

Dietary treatment is helpful in CKD patients, but nutritional interventions are scarcely implemented. The main concern of the renal diets is its feasibility with regards to daily clinical practice especially in the elderly and co-morbid patients. This study aimed to evaluate the effects of a pragmatic, step-wise, personalized nutritional support in the management of CKD patients on tertiary care.

Methods

This is a case-control study. It included 823 prevalent out-patients affected by CKD stage 3b to 5 not-in-dialysis, followed by tertiary care in nephrology clinics; 305 patients (190 males, aged 70 ± 12 years) received nutritional support (nutritional treatment Group, NTG); 518 patients (281 males, aged 73 ± 13 years) who did not receive any dietary therapy, formed the control group (CG). In the NTG patients the dietary interventions were assigned in order to prevent or correct abnormalities and to maintain a good nutritional status. They included manipulation of sodium, phosphate, energy and protein dietary intakes while paying special attention to each patient’s dietary habits.

Results

Phosphate and BUN levels were lower in the NTG than in the CG, especially in stage 4 and 5. The prevalence of hyperphosphatemia was lower in the NTG than in CG in stage 5 (13.3 % vs 53.3 %, p < 001, respectively), in stage 4 (4.1 % vs 18.3 % vs, p < 0.001) and stage 3b (2.8 % vs 9.5 % p < 0.05). Serum albumin was higher in NTG than in CG especially in stage 5 . The use of calcium-free intestinal phosphate binders was significantly lower in NTG than in CG (11 % vs 19 % p < 0.01), as well as that of Erythropoiesis stimulating agents (11 % vs 19 %, p < 0.01), and active Vitamin D preparations (13 % vs 21 %, p < 0.01).

Conclusions

This case-control study shows the usefulness of a nutritional support in addition to the pharmacological good practice in CKD patients on tertiary care. Lower phosphate and BUN levels are obtained together with maintenance of serum albumin levels. In addition, a lower need of erythropoiesis stimulating agents, phosphate binders and active Vitamin D preparations was detected in NTG. This study suggests that a nutritional support may be useful in the management of the world-wide growing CKD burden.

[New oral anticoagulants (NOAC) in nephrology]

The new or direct oral anticoagulants [new oral anticoagulants (NOAC) or direct oral anticoagulants (DOAC)] were launched in the Italian market in 2013. Although these compounds share common pharmacological indications with vitamin K antagonists (warfarin or acenocumarol), they have different mechanisms of action, do not require a constant anticoagulant monitoring but are more efficacious and safer than vitamin K antagonists. The use of these molecules (Dabigatran, Apixaban, Rivaroxaban, Betrixaban, Edoxaban) is constantly rising in daily practice. However, while available data suggest that NOAC/DOAC use is safe, dosage should be adjusted based on renal or liver function. It should be acknowledged that commonly available blood tests [Prothrombin Time (PT) and partial thromboplastin time (PTT)] are not indicated to monitor the anticoagulant activity of these compounds. With the exception of dabigatran, we currently lack of an antidote to reverse the anticoagulant effect of NOAC/DOAC. We herein review available evidence on NOAC/DOAC pharmacokinetic, risk factors for bleeding, interventions to reverse the anticoagulant activity in case of hemorrhages or need of urgent surgery and/or NOAC/DOAC overdose or side effects.

Muscle stimulation in elderly patients with CKD and sarcopenia

OBJECTIVES

Aim of our study was to assess the potential effects of high-tone external muscle stimulation (HTEMS) on improvement of endothelial dysfunction (ED) and kidney damage in elderly patients with chronic kidney disease (CKD), sarcopenia and/or serious physical disability with a high Multidisciplinary Prognostic Index (MPI).

METHODS

We enrolled 12 consecutive CKD patients with MPI > 0,66 from January 1st, 2008 to December 31st, 2014. Six patients underwent a 2-hours HTEMS during the first day (group A) and the other six patients (group B) underwent a sham experiment with HTEMS without power supply. After 24 hours, patients of group A were shifted to group B and vice-versa. Nitrite/nitrate (NOx), endotheline-1 (ET-1) and urine creatinine concentration were measured in all patients.

RESULTS

During HTEMS urine amount increased by 22% (p=0.049), so did urine creatinine that increased by 40%, (p=0.034) and creatinine clearance that increased by 26% (p=0.041). There was no statistical difference in urine nitrogen (that raised by 11%, p=0.526), urine sodium (that reduced by 42%, p=0.121) and urine potassium levels (p=0,491). At the same time, NOx changed from 44.15.1 to 38.45.3 M/L after 1 hour, to 36.44.8 M/L after 2 hours, to 41.15.7 M/L after 3 hours and to 46,95.0 M/L after 4 hours (p=0.008) during HTEMS, while it did not vary during the sham section of the experiment, respectively 43.66.1 M/L , 436.4 M/L, 42.85.5 M/L, 434.7 M/L, and 42.85.8 M/L (p=0.992).

CONCLUSION

Our study showed that HTEMS may improve microcirculation and, through this mechanism, may reduce kidney damage in elderly patients with CKD and severe muscle atrophy.

[Mystery diagnosis: "the Rolling Stones' syndrome"]

We present an unusual case of a young patient regularly followed in our Chronic Renal Insufficiency ambulatory with the periodicity of 2-3 visits per year--with stabilization of his residual renal function. The patient came to the emergency department declaring abdominal pain but make a diagnosis turned out to be more complicated than we expected.

Sevelamer is cost-saving vs. calcium carbonate in non-dialysis-dependent CKD patients in italy: a patient-level cost-effectiveness analysis of the INDEPENDENT study

OBJECTIVES

To conduct a cost-effectiveness analysis of sevelamer versus calcium carbonate in patients with non-dialysis-dependent CKD (NDD-CKD) from the Italian NHS perspective using patient-level data from the INDEPENDENT-CKD study.

METHODS

Patient-level data on all-cause mortality, dialysis inception and phosphate binder dose were obtained for all 107 sevelamer and 105 calcium carbonate patients from the INDEPENDENT-CKD study. Hospitalization and frequency of dialysis data were collected post hoc for all patients via a retrospective chart review. Phosphate binder, hospitalization, and dialysis costs were expressed in 2012 euros using hospital pharmacy, Italian diagnosis-related group and ambulatory tariffs, respectively. Total life years (LYs) and costs per treatment group were calculated for the 3-year period of the study. Bootstrapping was used to estimate confidence intervals around outcomes, costs, and cost-effectiveness and to calculate the cost-effectiveness acceptability curve. A subgroup analysis of patients who did not initiate dialysis during the INDEPENDENT-CKD study was also conducted.

RESULTS

Sevelamer was associated with 0.06 additional LYs (95% CI -0.04 to 0.16) and cost savings of EUR -5,615 (95% CI -10,066 to -1,164) per patient compared with calcium carbonate. On the basis of the bootstrap analysis, sevelamer was dominant compared to calcium carbonate in 87.1% of 10,000 bootstrap replicates. Similar results were observed in the subgroup analysis. RESULTS were driven by a significant reduction in all-cause mortality and significantly fewer hospitalizations in the sevelamer group, which offset the higher acquisition cost for sevelamer.

CONCLUSIONS

Sevelamer provides more LYs and is less costly than calcium carbonate in patients with NDD-CKD in Italy.

Physical activity in chronic kidney disease: a plausible approach to vascular calcification?

Vascular calcification (VC) is a prominent feature that affects up to 40 to 80% of Chronic Kidney Disease (CKD) patients depending on the degree of renal impairment. Though etiology and pathogenesis of the different types of VC are far from being elucidated, it is conceivable that an imbalance between promoters and inhibitors represents the condition that triggers VC deposition and progression. In addition to traditional cardiovascular risk factors, several lines of evidence suggest that specific factors may affect the arterial system and prognosis in CKD. Over the last decade, a few pharmacological strategies aimed at controlling different selected risk factors for VC have been investigated yielding conflicting results. In light of the complicated interplay between inhibitors and promoters as well as the fact that VC represents the result of cumulative and prolonged exposure to multiple risk factors, a more comprehensive risk modification approach such as lifestyle modification or physical activity (PA) may represent a valid strategy to attenuate VC deposition and progression.We herein aim at reviewing the rationale and current evidence on the potential for lifestyle modification with a specific focus on PA as a cost-effective strategy for VC treatment.

Parathyroid hormone may be an early predictor of low serum hemoglobin concentration in patients with not advanced stages of chronic kidney disease

Background

Parathyroid hormone (PTH) has been associated with anemia only in dialysis patients with severe hyperparathyroidism. Whether an association between PTH and hemoglobin also exists in patients with chronic kidney disease not on dialysis (CKD-patients) is still unclear. In this study we evaluated the association between PTH and hemoglobin in CKD-patients without severe secondary hyperparathyroidism.

Methods

Hospitalized patients and outpatients (N = 979) were retrospectively evaluated and categorized according to PTH quartile and serum hemoglobin (<12.0, <11.0, <10.0 g/dl). Gender, diabetes, glomerular filtration rate (GFR), hemoglobin, PTH, markers of mineral metabolism, inflammation, iron status and nutrition were variables of adjustment in univariate and multivariate analysis.

Results

An inverse association (p = 0.001) was observed between PTH and hemoglobin in patients as a whole, in diabetics, and in patients with GFR ≤60 ml/min. PTH was the single predictor of low hemoglobin in patients as a whole (unstandardized beta −2.12; p = 0.005), in diabetics (unstandardized beta −8.86; p = 0.007) and in patients with GFR ≤60 ml/min (unstandardized beta −2.52; p = 0.006). For each increase of quartile of PTH the risk of having hemoglobin level <10.0 mg/dl was more than doubled [hazard ratio (HR) 2.79, 95 % confidence interval (CI) 2.00–3.88; p = 0.001]. The receiver operating characteristic curve showed that PTH ≥122 pg/ml had 67 % sensitivity and 75 % specificity in predicting hemoglobin level <10.0 g/dl with area under the curve of 0.758 (95 % CI 0.73–0.78).

Conclusions

This study shows a significant inverse association between PTH and hemoglobin levels across the whole spectrum of non-dialysis CKD and a doubled risk of having serum hemoglobin <10.0 mg/dl in the absence of severely deranged PTH concentration. These findings may have clinical relevance in ascertaining the cause of unexplained low hemoglobin levels in CKD-patients.

Very low-protein diet plus ketoacids in chronic kidney disease and risk of death during end-stage renal disease: a historical cohort controlled study

BACKGROUND

Very low-protein intake during chronic kidney disease (CKD) improves metabolic disorders and may delay dialysis start without compromising nutritional status, but concerns have been raised on a possible negative effect on survival during dialysis. This study aimed at evaluating whether a very low-protein diet during CKD is associated with a greater risk of death while on dialysis treatment.

METHODS

This is an historical, cohort, controlled study, enrolling patients at dialysis start previously treated in a tertiary nephrology clinic with a very low-protein diet supplemented with amino acids and ketoacids (s-VLPD group, n = 184) or without s-VLPD [tertiary nephrology care (TNC) group, n = 334] and unselected patients [control (CON) group, n = 9.092]. The major outcome was survival rate during end-stage renal disease associated to s-VLPD treatment during CKD. The propensity score methods and Cox regression model were used to match groups at the start of dialysis to perform survival analysis and estimate adjusted hazard ratio (HR).

RESULTS

In s-VLPD, TNC and CON groups, average age was 67.5, 66.0 and 66.3 years, respectively (P = 0.521) and male prevalence was 55, 55 and 62%, respectively (P = 0.004). Diabetes prevalence differed in the three groups (P < 0.001), being 18, 17 and 31% in s-VLPD, CON and TNC, respectively. A different prevalence of cardiovascular (CV) disease was found (P < 0.001), being similar in TNC and CON (31 and 25%) and higher in s-VLPD (41%). Median follow-up during renal replacement therapy (RRT) was 36, 32 and 36 months in the three groups. Adjusted HR estimated on matched propensity patients was 0.59 (0.45-0.78) for s-VLPD versus CON. Subgroup analysis showed a lower mortality risk in s-VLPD versus matched-CON in younger patients (<70 years) and those without CV disease. No significant difference in HRs was found between s-VLPD and TNC.

CONCLUSION

s-VLPD during CKD does not increase mortality in the subsequent RRT period.

[The devil teaches us his tricks... and also how to hide them]

Spontaneous ureteric ruptures is a rare condition [1]and bilateral ureteric rupture is even more uncommon. Few cases are described in the literature in which bilateral ureteric rupture is associated to dermatomyositis [2]or to intra-arterial contrast medium application for infrarenal aortic stent placement [3]. We discuss here a case of bilateral ureteric rupture in a 74-year-old man with bladder cancer, presenting oliguric acute kidney failure and a light abdominal pain.

[An unusual case of acute kidney insufficiency]

Acute aortic dissection (AAD) is a life-threatening condition with high morbidity and mortality, that involves renal arteries in at least 5-10% so leading to renal ischemia and insufficiency. AAD presenting with anuria and the necessity of renal replacement therapy occurs rarely. Here we describe a case of a hypertensive and obese patient presenting with anuria and acute kidney injury, who underwent to hemodialysis and later was diagnosed with aortic dissection. Through this case, we underline the importance of considering AAD as an important differential in patients with a long history of uncontrolled hypertension presenting with anuria.

Does Vascular Calcification Correlate with Pulse Wave Velocity in Hemodialysis Patients?

Vascular calcifications have been previously shown to be an independent predictor of mortality in dialysis patients and a similar association has been shown for arterial stiffness. Nonetheless, the relationship between vascular calcifications and pulse wave velocity (PWV) have so far been little explored. The goal of this study is to verify the correlation among vascular calcifications and rigidity of arterial wall in patients at dialysis start. Accordingly, we investigated the association between aortic PWV and coronary calcification measured by computed tomography (TC-score) in 105 adult incident hemodialysis patients. PWV resulted increased in patients with the higher TC-score values; indeed, at univariate analysis PWV directly correlated with age (p=0.016), presence of diabetes (p<0.0001), serum phosphorus (p=0.0066), C-reactive protein (CRP) (p=0.046), LDL-cholesterol (p=0.043), TC-score (p<0.0001), and inversely correlated with systolic blood pressure (p=0.036). At multivariate analysis, age, diabetes, serum phosphorus, CRP, LDL-cholesterol and vascular calcifications were determinants of arterial stiffening. Using the table “two for two”, we showed 6 false negative patients (high TC-score and low PWV) and 12 false positive patients (low TC-score and high PWV). The sensibility was 76% and the specificity 85%; the accuracy was 83%, the predictor positive value was 61% and the predictor negative value was 92%. Overall, a strong association between TC-score and PWV was seen.

[Inhibition of the renin-angiotensin system in HIV nephropathy]

It is estimated that 1-2 % of patients starting dialysis suffers from kidney disease associated with HIV infection. HIV-associated nephropathy ( HIVAN ) develops in about 10% of people living with HIV , with different preference for Blacks and Hispanics . Since the beginning of large-scale use of antiretroviral therapy (ART), the HIVAN has been characterized by a rapid decline in renal function , with progression to ESRD ( End - Stage Renal Disease ). Aside from HIV direct damage to the nephron, numerous experimental observations support the argument that the agiotensina II contributes to the podocytes damage. Treatment with ACE - inhibitors (ACE - Is) , as well as the one with angiotensin receptor blockers ( ARBs), may attenuate the decline in renal function in HIVAN . However, clinical data on the effects of these antihypertensive agents in HIV-infected individuals are still scarce and doubts have yet to be adequately addressed. In the following, we analyze the studies that have investigated the use of ACE -Is and ARBs in the treatment of hypertension and albuminuria in patients with HIVAN.

[Phosphate control in end stage renal disease: barriers and opportunities. Malnutrition: yes or not?]

The fear of malnutrition, caused by the low-protein diet, conditions in an inappropriate use of a useful nutrition therapy in Chronic Kidney Disease. Often malnutrition is due to reduced intake of energy, because a low (or very low) protein proper diet with adequate amount of calories (30-35 cal/kg bw/day). We analyze the positive aspects of the low-protein diet for optimal control of hypertension, hyperphosphatemia, anemia, and proteinuria that is the goal of pharmacological management Chronic Kidney Disease patients.

[Hemodialysis improves the subendocardial viability ratio]

The subendocardial viability ratio (SEVR), a parameter introduced by Buckberg, represents a non-invasive measure of myocardial perfusion related to left ventricular work. AIM. The aim of this study was to verify if dialysis may determine modifications of SEVR and how these modifications are modulated in the 2-day interdialytic period. METHODS.We studied 54 subjects of mean age 6314 years and receiving dialysis for 3215 months. Exclusion criteria were diabetes, resistant hypertension and peripheral vascular diseases and intradialytic hypotension evidenced during the study dialysis session. Pulse wave velocity and SEVR assessments were performed during the third dialysis session of the week, before (pre-HD) and after (post-HD) dialysis, in 2-day interdialytic period after and at the beginning of the following dialysis session. RESULTS.Dialysis reduces PWV, in particular the tertile with the lowest PWV presents the highest percentage reduction (-26%) compared with the second and the third tertiles. In the same way, dialysis leads to an increase of SEVR and patients in the tertile with the highest SEVR values maintain high SEVR values during dialysis and in the interdialytic period. Patients with severe vascular calcifications present higher PWV value and lower SEVR value. CONCLUSIONS.The results of present study demonstrate that ultrafiltration improves PWV (with a mean reduction of 16%) and SEVR (increase of 13%) and that the severity of vascular calcifications influences the effect of ultrafiltration on these two parameters. More studies are certainly necessary to verify our findings. Considered the higher mortality of patients with higher SEVR, it would be important to understand if new dialytic strategies are needed in patients with higher PVW and lower SEVR values.