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F Coronel

Publications and source records attributed to F Coronel.

At least 19 recordsLinked to original sources
PubMed2006

[Guidelines of the Spanish Society of Nephrology. Clinical practice guidelines for peritoneal dialysis].

In Spain and in each of its autonomous communities, the dialysis treatment of chronic renal disease stage 5 is totally covered by public health. Peritoneal dialysis, in any of its modalities, is established as the preferred home dialysis technique and is chosen by high percentage of patients as their choice in dialysis treatment. The Spanish Society of Nephrology has promoted a project of creation of performance guides in the field of peritoneal dialysis, entrusting a work group composed of members of the Spanish Society of Nephrology a with the development of these guides. The information offered is based on levels of evidence, opinion and clinical experience of the most relevant publications of the topic. In these guides, after defining the concept of << peritoneal dialysis>>, the obligations and responsibilities of the sanitation team of the peritoneal dialysis unit are determined, and protocols and performance procedures that try to include all the aspects that concern the patient with chronic renal disease in substitute treatment with this technique are developed. They propose prescription objectives based on available clinical evidence and, lacking this, on the consensus of the experts' opinions. The final aim is to improve the care and quality of the of the patient in peritoneal dialysis, optimizing in this way the survival of the patient and of the technique. In Spain, as in other neighbouring countries, peritoneal dialysis has an incidence and prevalence that is much lower than that of hemodialysis, ranging in the last evaluation by the Spanish Society of Nephrology between 5 and 24% in the different autonomous communities. The great majority of peritoneal dialysis units form part of the public network of the Spanish state, with special representation as a Satellite Unit or Concerted Center related to the public hospital of reference, on which it must depend.

Humans↗
PubMed2004

Pure red-cell aplasia induced by anti-erythropoietin antibodies in peritoneal dialysis.

There have been several recent reports of pure red-cell aplasia (PRCA) mediated by anti-erythropoietin antibodies (AEA) in patients with chronic renal failure treated with recombinant human erythropoietin (EPO). Among the factors thought to trigger this mechanism is the subcutaneous administration of EPO. Despite this being the normal route of administration in patients undergoing peritoneal dialysis (PD), to date there has only been 1 described case of PRCA due to AEA in PD. Herein, we report such a case involving a patient in whom a diagnosis of anemia due to PRCA was particularly difficult to make because of concomitant rectal bleeding.

Antibodies↗
PubMed2003

[Thomas' shunt for hemodialysis: dysfunction and its percutaneous treatment].

PURPOSE: To assess the usefulness of percutaneous treatment of abnormalities of the venous tree in extending the survival of external Thomas shunts (TS). MATERIALS AND METHODS: Twelve cases of TS were included in a hemodialysis access fistula dysfunction monitoring program and were followed for up to 48 months. The abnormalities found were treated by percutaneous transluminal angioplasty (PTA) or thrombolysis and PTA. Survival curves and the Kaplan-Meier method were used to calculate the likelihood of primary patency (P1), secondary patency (P2), and overall patency (OP). RESULTS: A total of 61 interventions were performed during the period of follow-up. On 12 occasions the fistula was thrombosed; in the rest, increased venous pressure to 150 mmHg or higher was detected during dialysis. Fistulography was performed after washing the thrombosed fistulas with urokinase, and revealed one or more of the following angiographic signs: 1) a short reduction of more than 50% in lumen caliber in the femoral vein adjacent to the anastomosis, present in 52% of the cases (fig. 1); 2) imaging a "jet" of contrast material at the site of entry of the shunt into the femoral vein (fig. 2), present in 22% of the cases; and 3) a filling defect or "flap" at the same site, owing to hyperplastic tissue or piece of thrombus adhering to the intima, present in 34% of the cases (figs. 3-5). This last-mentioned finding ordinarily gave rise to a "valve" effect, whereby injection into the venous branch was feasible but aspiration from the venous branch was difficult or impossible. PTA was carried out and attained anatomical and functional success in 100% of cases. PI was 58%, 33%, 8%, and 0% at 6, 12, 24, and 36 months, respectively; P2 was 100%, 75%, 58%, and 25%; respectively, at those same times. The comparison of the PI and P2 curves was statistically significant; p < 0.001 (table 1). OP was 83%, 66%, 50% and 41% at 12, 24, 36 and 48 months. The comparison of the PI surgical and OP curves was statistically significant; p < 0.01 (table II). CONCLUSIONS: Percutaneous treatment of TS dysfunction was proved to be effective in maintaining long-term patency. This type of fistula affords an alternative to tunneled central venous catheters.

Adult↗
PubMed2002

Pulmonary diffusing capacity in chronic dialysis patients.

Patients with end-stage renal disease treated by hemodialysis with bioincompatible membranes are exposed during the dialysis period to acute effects on lung microcirculation, which may result in pulmonary fibrosis and diffusion defects in long-standing dialysis. To investigate the occurrence of these possible chronic pulmonary alterations, we determined lung function in patients with chronic renal failure not undergoing hemodialysis and in patients who had been receiving regular hemodialysis both for short and long periods of time. Forty-three patients divided into three groups were studied: 17 patients before dialysis with a mean (SD) creatinine clearance of 14.1 (6.8) ml/min 11.73 m2, 10 patients receiving regular hemodialysis for a period of less than 12 months (mean 6.4 +/- 3.5 months), and 16 patients receiving regular hemodialysis for more than 5 years (mean 8.3 +/- 3.6 years). First-use bioincompatible cellulosic dialysis membranes were used in all the cases. The following parameters were recorded: forced vital capacity (FVC), forced expiratory volume in 1s (FEV1), total lung capacity (TLC), residual volume (RV), carbon monoxide transfer factor (TLCO), accessible lung volume (VA), carbon monoxide transfer factor/accessible lung volume (KCO- that is, TLCO/VA), and arterial blood gases. Patients receiving regular hemodialysis for more than 5 years showed significantly lower values of TLCO and KCO than patients before dialysis and patients receiving regular hemodialysis for less than 12 months. Seventy-five percent of patients on long-term hemodialysis had markedly reduced TLCO or KCO values (below 80% of the reference value) as compared with 17% of patients before dialysis and 10% of patients dialyzed for less than 12 months (P < 0.001). Differences among groups for the remaining parameters were not observed. In conclusion, patients undergoing long-term regular hemodialysis with a bioincompatible membrane showed a selective reduction in pulmonary diffusing capacity possibly due to chronic pulmonary fibrosis.

Aged↗
PubMed2002

[Anemia management in haemodialysis. EuCliD database in Spain].

We present the results on Anaemia Management in Fresenius Medical Care Spain dialysis centres as reported by EuCliD (European Clinical Database), evaluating a population of 4,426 patients treated in Spain during the year 2001. To analyse the erythropoietin dose and the haemoglobin levels we divided the population in two groups according to the time with dialysis treatment: patients treated less than six months and patients between six months, and four years on therapy. We compared our results with the evidence based recommendations Guidelines: the European Best Practice Guidelines (EBPG) and the US National Kidney Foundation (NKF-K/DOQI). We also compared our results with those presented by the ESAM2 on 2,618 patients on dialysis in Spain carried out in the second half of the year 2000. We observed that 70% of the population reaches an haemoglobin value higher that 11 g/dl, with a mean erythropoietin (rHu-EPO) dose of 111.9 Ul/kg weight/week (n = 3,700; SD 74.9). However, for those patients on treatment for less than six months, the mean Haemoglobin only reaches 10.65 g/dl (n = 222; SD 1.4). The rHu-EPO was administrated subcutaneously in 70.2% of the patients. About the iron therapy, 86% of the patients received iron treatment and the administration route was intravenous in 93% of the population. The ferritin levels were below 100 micrograms/dl in 10% of the patients and 26.4% showed a transferrin saturation index (TSAT) below 20%. The erythropoieting resistance index (ERI), as rHu-EPO/haemoglobin, has been used to evaluate the response to rHu-Epo, according to different variables. It was observed that the following factors lead to a higher rHu-EPO resistance: intravenous rHu-EPO as administration route, the presence of hypoalbuminemia, increase of protein C reactive, Transferrin saturation below 20% and starting dialysis during the last six months.

Anemia↗
PubMed2001

Long-term experience with the Thomas shunt, the forgotten permanent vascular access for haemodialysis.

BACKGROUND: Vascular access complications are the main cause of hospitalization in dialysis patients. The difficulty in creating and maintaining vascular access after several years on haemodialysis (HD) remains the primary problem in these patients. The femoro-femoral Thomas shunt is a permanent vascular access that was used in the 1970s and is all but forgotten at present. We analysed our experience with the Thomas shunt since 1979 in patients with no other possibility of regular vascular access. METHODS: We retrospectively studied 27 Thomas shunts implanted in 10 patients, aged 27-75 years at the time of first shunt implantation. Prior to implantation of the Thomas shunt, these patients had experienced 80 failed vascular accesses (plus four patients on CAPD), with an average of 8.6 accesses per patient. All Thomas shunts were implanted in femoral vessels. Clinical data were extracted from hospital and dialysis unit records and were analysed for efficacy, complications, and duration of patency. RESULTS: Total follow-up was 1176 months, with an average shunt duration of 43.7 months (range 3-151 months). One-, 2-, 3- and 6-year survival rates were 85, 57, 49 and 25% respectively. Five patients spent more than 10 years on HD using the Thomas shunt, and one patient had the same unit for 12.5 years. A high blood flow (450 ml/min) was obtained, without recirculation, due to the characteristics of this shunt. Efficacy, measured as percentage urea reduction (PRU), was high (on average 77.8+/-1.5%). The infection incidence was one episode every 37.5 patient-months, Staphylococcus species being the most commonly isolated. There were no shunt removals because of infection. The most important cause of shunt withdrawal was thrombosis, with an incidence of one episode every 7 patient-months. Percutaneous angioplasty was successful in the majority of stenosis episodes. CONCLUSIONS: This study indicates that the Thomas shunt provides a good permanent vascular access for HD patients who have no other possibility of a regular vascular access. This shunt offers high dialysis efficacy without recirculation and an access duration comparable to AV fistulae. For these reasons the Thomas shunt should continue to be used as a vascular access in HD.

Adult↗
PubMed2001

[Calciphylaxis: an uncertain pathogenesis and controversial treatment].

Calciphylaxis is an uncommon but serious disease process that affects mainly patients with advanced renal failure. Calciphylaxis is characterized by dermal arteriolar calcification that leads to skin ulceration, necrosis, ischemia and secondary infection. The pathogenesis is poorly understood, although the calcium phosphorus product has been proposed as a major cause. Given the high morbidity and mortality rate, emphasis should be placed on prevention and early diagnosis of vascular calcification, as well as in prophylaxis of secondary infection. We present changing concepts in four patients receiving dialysis.

Aged↗
PubMed1997

Calcium salts of keto-amino acids, a phosphate binder alternative for patients on CAPD.

Control of hyperphosphoremia is crucial to the prevention of secondary hyperparathyroidism. Calcium salts of keto-amino acids (KAA) were employed as phosphate binders in hemodialysis patients. We wanted to assess the efficacy of these substances as quelating agents in patients under continuous ambulatory peritoneal dialysis (CAPD). Also, as an amino acid supplement, we determined their possible effect on some parameters related to nutritional status. We studied 13 patients (7 M; 6 F) with a mean age of 45.2 +/- 17 years and a mean time on CAPD of 18.4 +/- 11.4 months. None had severe secondary hyperparathyroidism and/or clinically relevant aluminium intoxication. They were not receiving calcitriol and none were using low-calcium peritoneal dialysis fluids. All were under aluminum hydroxide (AlOH3) treatment and 8 patients also received calcium carbonate. These quelating agents were withdrawn and after 21 days (wash-out period) KAA were initiated. We analyzed serum levels of bone metabolism parameters (calcium, phosphate, osteocalcin [OC], intact parathyroid hormone [iPTH], alkaline phosphatase [AP]) and nutritional parameters (total protein, albumin, pre-albumin, transferrin) in four periods: (A) during AlOH3; (B) immediately after the washout period; (C) after 1.5 months; and (D) after 3 months of KAA therapy. In 5 patients serum aluminum level was also measured in periods (A) and (D). The serum phosphate level at period (B) was significantly higher than in other periods. After 3 months of treatment phosphate levels decreased significantly (A = 1.77 +/- 0.3 mmol/l vs D = 1.48 +/- 0.2; p < 0.05). Serum calcium levels increased, while iPTH and OC decreased (p = ns). AP remained stable during the study. All nutritional parameters increased at the end of the study (p = ns). Calcium salts of keto-amino acids showed to be an effective alternative to aluminum-containing phosphate binders. They were well tolerated, without relevant side-effects. These compounds could also represent an additional source of oral amino acid supplementation with improvement of nutritional status.

Administration, Oral↗
PubMed1996

Double renal transplant from infant donors. A good alternative for adult recipients.

Several groups have reported technical complications and poor graft survival rates in kidney transplants from pediatric donors to adult recipients. Increased incidences of acute rejections, vascular thrombosis, and early glomerulosclerotic lesions have led many groups to abandon this graft combination. Over the last 4 years, we have set up a program of two-kidney transplantation from cadaveric infant donors under age 3 years, which to date includes 15 adult recipients. Thirteen of these grafts are currently functioning at least as well as those from adult donors, after a mean follow-up of 1.5 years. Our surgical and therapeutic procedures have led to a minimization of the early complications reported by other groups. With this transplantation procedure, the patients receive double the number of nephrons, which will probably give them better long-term function. The encouraging results achieved by our group may help change the current consideration of pediatric donors as "suboptimal" ones.

Adolescent↗
PubMed1996

Abnormalities of heme biosynthesis in experimental acute renal failure.

Several abnormalities of porphyrin metabolism have been described in patients with end-stage renal failure. Because the heme biosynthetic pathway in acute renal failure has not been studied hitherto, an experimental model was therefore induced in 30 dogs by ligation and transection of both ureters. Forty-eight h after this procedure, anemia and uremia developed, erythrocyte aminolevulinate dehydratase activity decreased, and plasma porphyrins increased in these 30 dogs, whereas seven sham-operated animals did not exhibit any alteration of these parameters. Uremic plasma showed a capacity to inhibit aminolevulinate dehydratase activity (mean, 11.1 +/- 5.8%) when incubated in vitro with erythrocytes from healthy dogs. Such findings are similar to those reported in uremic patients on hemodialysis or on continuous ambulatory peritoneal dialysis. Twenty-three of the 30 animals underwent a hemodialysis session (180 min) 48 h after ureteral ligation, using a polyacrylonitrile membrane dialyzer. In addition to reducing serum creatinine and urea levels, this procedure significantly reduced plasma porphyrin values. However, the activity of erythrocyte aminolevulinate dehydratase and the plasma capacity to inhibit this enzyme were not modified after the hemodialysis session. This results described here show that some of the abnormalities of heme biosynthesis described in chronic renal failure are detected early in an experimental model of acute renal failure. This study also confirms that, although most plasma porphyrins circulate bound to proteins, hemodialysis may reduce levels of plasma porphyrins when a high permeability membrane is used.

Acute Kidney Injury↗
PubMed1996

Effects of recombinant human erythropoietin on porphyrin metabolism in uremic patients on hemodialysis.

Recombinant human erythropoietin (r-HuEPO) is being successfully used for the treatment of uremic anemia. Several abnormalities of heme biosynthetic pathway have been described in patients with end-stage renal failure. In this condition, the activity of erythrocyte porphobilinogen deaminase has been found to be slightly increased. If this enzyme were to be the key enzyme in erythroid heme regulation, its activity would be increased to an even greater degree during the correction of uremic anemia. To assess this hypothesis, this study followed the variations of this and other parameters of porphyrin metabolism over 12 months of erythropoietin therapy in eight patients with nephrogenic anemia who underwent hemodialysis. By the first month of therapy, an increase of the previously depressed erythrocyte activity of aminolevulinate dehydratase was already evident, in coincidence with a nonsignificant increase of the reticulocyte count. The activity of this enzyme reached its maximal level by Month 3, and did not change up to Month 10. The porphobilinogen deaminase hyperactivity normalized at Month 4. By Month 12, in coincidence with the reduction of erythropoietin doses, the maximal levels of erythrocyte protoporphyrin, and the decrease in aminolevulinate dehydratase activity, the porphobilinogen deaminase values started to increase once again. In conclusion, the administration of r-HuEPO to hemodialyzed patients induced transient normalization of the previously observed porphyrin metabolism abnormalities. However, erythrocyte porphobilinogen deaminase activity did not rise concomitantly with the increase in hematocrit or hemoglobin values, but it did diminish during treatment. Therefore, porphobilinogen deaminase did not behave as a controlling enzyme in heme synthesis during the r-HuEPO-induced correction of uremic anemia.

Adult↗
PubMed1995

Efficiency of three different hemodialysis membranes for plasma porphyrin removal.

To assess the capability of three different membranes to remove porphyrins, plasma and dialysate porphyrin levels were fluorometrically measured in 10 patients with end-stage renal failure who were on hemodialysis. Three different hemodialysis membranes were used: cuprophan, polyacrylonitrile, and cellulose triacetate. Total plasma porphyrin concentrations decreased after dialysis, but to a lesser extent when using the cuprophan membrane (19%) than with the polyacrylonitrile (26%) or cellulose triacetate (30%) membranes (P < 0.01). However, since the free plasma porphyrin fraction remained unchanged, it can be assumed that the equilibrium between protein-bound and non-protein-bound (free) porphyrins is displaced toward the latter fraction. Dialysate porphyrin levels were lower (P < 0.01) when using the cuprophan membrane (10.1 micrograms/session) than when using polyacrylonitrile (17.8 micrograms/session) and cellulose triacetate (21.9 micrograms/session). Although most of the plasma porphyrins are protein bound, our results show that hemodialysis can remove significant amounts of non-protein-bound (free) porphyrins. The polyacrylonitrile and cellulose triacetate membranes had a greater capacity for porphyrin removal than cuprophan. Thus, two high-permeability membranes (polyacrylonitrile and cellulose triacetate) should be used whenever a reduction of plasma porphyrin levels is desired.

Acrylic Resins↗
PubMed1994

Heme biosynthesis in uremic patients on CAPD or hemodialysis.

We have analyzed some parameters of porphyrin metabolism in 60 patients with end-stage renal failure, 20 of them on CAPD and the remaining on HD. In comparison with 56 control subjects, both groups of patients showed the three following findings: low erythrocyte aminolevulinate dehydrase activity, inhibition ability for the activity of this enzyme when their plasma was incubated in vitro with normal erythrocytes, and increased plasma porphyrin levels. Like anemia, these abnormalities were more remarkable in patients on HD who also exhibited increased erythrocyte protoporphyrin levels and compensatory porphobilinogen deaminase activities. Mean weekly porphyrin removal through dialysate was higher in CAPD (90.8 micrograms) than in HD patients (30.4 micrograms). Dialysate and plasma porphyrins were correlated in both circumstances (r = 0.714, P < 0.01 and r = 0.637, P < 0.05, respectively). The less pronounced porphyrin abnormalities found in CAPD patients with respect to HD patients may be due to the more efficient capability of peritoneal dialysis for removing from plasma protein-bound substances, as porphyrins and inhibitors of aminolevulinate dehydrase or other enzymes involved in erythropoiesis. Since no close relationship was found between these abnormalities of porphyrin metabolism and hematocrit values, the anemia of uremia cannot be merely considered as a direct consequence of altered heme biosynthetic pathway.

Adolescent↗