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M Albalate

Publications and source records attributed to M Albalate.

18 recordsLinked to original sources
PubMed2004

[Reticulocyte response after immediate withdrawal of recombinant human erythropoietin in chronic hemodialysis patients].

UNLABELLED: The sudden interruption of recombinant human erythropoietin (rHuEPO) in end-stage renal disease (ESRD) patients leads to rapid anemization. The mechanisms of this phenomenon are, however, insufficiently understood. The present study examined the response to immediate rHuEPO withdrawal in dialysis patients. METHODS: 10 chronic hemodialysis (HD) patients regularly receiving rHuEPO were studied. rHuEPO was stopped and reinitiated after 7 days. Reticulocyte profile, haemoglobin and haematocrit were measured at 0, 7 and 15 days. As a complementary study, and with the purpose of analyzying whether uremia was a relevant factor, 10 non-uremic male Wistar rats were treated with rHuEPO. After two weeks, rHuEPO was withdrawn in 5 animals, and continued for 7 additional days in the remainder. The same variables than in the human study were determined. RESULTS: Changes in reticulocyte subtypes from baseline to day 7 were: total 18.2 +/- 0.9 vs 14.3 +/- 1.8% (p < 0.06); high-fluorescence (HFR): 2.6 +/- 0.4 vs 0.75 +/- 0.2 (p < 0.001); medium-fluorescence (MFR): 13.0 +/- 1.1 vs 6.6 +/- 0.9% (p < 0.02); and low-fluorescence (LFR): 84.2 +/- 1.4 vs 92.7 +/- 1% (p NS). The baseline pattern was recovered upon 7 days of rHuEPO reinitiation (p NS). Mean hemoglobin and hematocrit decreased by day 14 (p < 0.02) in spite of rHuEPO reinitiation at day 7. In non-uremic rats, changes were similar to that in the ESRD patients. CONCLUSION: rHuEPO induces changes in the reticulocyte pattern, consisting in a reduction of immature reticulocytes. These changes appear to be independent of the presence of uremia. Accordingly, complete rHuEPO withdrawal in HD patients will cause a rapidly-developing anaemia due to an alteration in the reticulocyte maturation series; therefore, sudden rHuEPO interruption should be avoided whenever is possible. As a collateral application, the specific changes described herein have potential use for detecting illegal administration of rHuEPO.

Aged↗
PubMed2003

[Hypophosphatemia in dialysis units].

Hypophosphatemia (Hf) is infrequently reported in chronic hemodialysis patients. The objective of this report is to describe the incidence, etiology, symptoms and treatment of Hf in a Dialysis Unit (defined as phosphorus < 2.5 mg/dL). In a retrospective study over a period of three years, we identified 22 cases of Hf, occurring on 11 among 149 patients. A two-groups distribution was made: Group A, patients with more than one episode (n = 3, 14 episodes of Hf) and Group B, patients with only one isolated episode of Hf (n = 8, 8 episodes of Hf). Plasma Ca, P, Albumin and nPCR were significant lower in group A (p < 0.05). Only two patients of group B had symptoms. Cases of Hf were: Group A: low-protein diet and alcoholism, Group B: decreased dietary intake due to non-digestive problems (n = 2) or due to digestive problems plus antacids (n = 4), phos-phate binders (n = 1) and dietary phosphorus restriction (n = 1). Three patients had secondary hyperparathyroidism. Treatment consisted on oral supplementarion by diet and changes in oral calcium salts. Intravenous supplementation was required acutely to raise serum P in a patient with auricular fibrilation. Two group A patients who has plasma 1.25 vitamin D < 5 pg/mL received vitamin D, and the third oral supplements of P. In all the cases, Hf resolved with these measures. We concluded that Hf is not so infrequent in hemodialysis. In patients with low-protein diet and low vitamin D concentration, Hf can be sustained. On the other hand, a decreased dietary intake maintaining similar phosphate binder's supplementation is the most frequent cause of occasional and symptomatic Hf, even in patients with secondary hyperparathyroidism.

Female↗
PubMed2001

Role of type of vascular access in erythropoietin and intravenous iron requirements in haemodialysis.

BACKGROUND: Recent data have suggested the existence of a relationship between the use of synthetic vascular accesses and increased erythropoietin (Epo) requirements. The present study aimed to evaluate the possible role of the type of vascular access in both Epo and intravenous (i.v.) iron requirements. METHODS: One-hundred-and-seven individuals without recognized causes of Epo resistance, 62 of them undergoing chronic haemodialysis through native arteriovenous fistulae (AVF) and 45 through PTFE grafts, were retrospectively studied (one-year follow-up). Sixty-nine patients, i.e. all but three with a PTFE graft and 27 with native AVF, were taking anti-platelet agents. Doses of i.v. iron and Epo and laboratory parameters were recorded. RESULTS: Erythropoietin and i.v. iron requirements were higher in the patients dialysed through PTFE grafts compared with those with native AVF (Epo: 103.8+/-58.4 vs 81.0+/-44.5 U/kg/week, P=0.025; i.v. iron: 178.9+/-111 vs. 125.9+/-96 mg/month, P=0.01). On a yearly basis, the difference in Epo dose represented a total of 94582+/-16789 U Epo/patient/year. Moreover, the patients with PTFE grafts received more red blood cell transfusions than patients with native AVF (P=0.021). No differences between laboratory, dialysis kinetics, demographic or comorbidity parameters were found. The type of vascular access was the best predictor of the requirement of > or =150 U/kg/week Epo (P=0.03). Even though the patients who received anti-platelet therapy required more i.v. iron (167.5+/-103.6 vs. 114.5+/-101.4 mg/month, P=0.008) but not more Epo (P=NS), the possibility of an accessory role of anti-platelet agents in the increased Epo requirements with PTFE grafts cannot be ruled out. CONCLUSIONS: The use of a PTFE graft and anti-platelet drugs represents a previously undescribed association related to higher Epo and i.v. iron requirements. The association described herein adds new arguments to the debate concerning the choice of vascular access in chronic haemodialysis patients.

Aged↗
PubMed2001

Development of porphyria cutanea tarda in a hemodialysis patient after reactivation of hepatitis C virus infection.

Cases of porphyria cutanea tarda (PCT) are occasionally reported in hemodialysis patients. Recently, hepatitis C virus has been recognized as a precipitating factor of PCT. The activity of the liver disease may be critical for the appearance of PCT. In this regard, liver disease reactivation after treatment with interferon alpha (IFN-alpha) is a well-known phenomenon. We report the case of a hemodialysis patient who developed PCT coincidentally with reactivation of liver disease, immediately after treatment with IFN-alpha. Therefore, in the present case, reactivation of hepatitis after IFN-alpha withdrawal could be the triggering factor. The occurrence of a bout of PCT should be considered as a possible complication at the end of IFN-alpha therapy, if reactivation of the disease exists.

Antiviral Agents↗
PubMed2000

Hepatitis C virus RNA in kidney biopsies from infected patients with renal diseases.

Hepatitis C virus (HCV) infection has been associated with several renal pathologies, including membranoproliferative and membranous glomerulonephritis. Although the presence of HCV proteins has been reported, there are no data concerning detection of the viral RNA in renal cells from HCV-infected patients with kidney disease. In this report we analysed, by in situ hybridization, the presence of HCV RNA in renal biopsies from 10 patients who were positive for antibodies to HCV (anti-HCV) and serum HCV RNA positive, and from four patients without HCV infection, with different renal disease. HCV RNA was detected in the renal biopsies from all of the 10 HCV-infected patients. Hybridization signals were detected in the tubular and capillary endothelial cells. No hybridization signals were found in the renal biopsies of the four anti-HCV-negative patients. In conclusion, our results demonstrate that HCV RNA is common in kidney cells of patients with renal diseases who are infected with HCV. The presence of HCV RNA is not necessarily associated with a pathogenetic consequence.

Adult↗
PubMed1997

[Diagnosis of renovascular disease by heart catheterization].

Atherosclerotic renovascular disease is a common entity, particularly in persons older than 50 years of age and especially in those patients with other evidence of atherosclerotic vascular disease. The illness clearly progresses in some patients, and progression rate appears to be highly variable. Taken into account the apparent high prevalence of renovascular disease in older persons, it is possible that this disorder be the cause of end stage renal disease in 5% to 15% of patients currently entering the dialysis program each year. Surgery and percutaneous angioplasty can both improve renal function in patients with renal artery stenosis. We describe a patient in whom the detection of renovascular disease was made accidentally at the time of coronary arteriography. He presented an acute renal failure after use of angiotensin-converting enzyme inhibitors and/or contrast media associated nephrotoxicity, and was treated with percutaneous transluminal balloon angioplasty and had a successful outcome.

Acute Kidney Injury↗
PubMed1997

Concentrated ascitic fluid reinfusion in cirrhotic patients: a simplified method.

A new method for ascites filtration and reinfusion, which uses a single Cuprophan filter and is performed in the dialysis unit, is reported. Thirty-one procedures were performed in 17 patients with cirrhosis and massive ascites. A mean volume of 8.6 L of ascitic fluid was removed; from this volume, 5 L were ultrafiltered and a concentrated ascitic fluid was reinfused (x = 359.8 mL). The whole procedure was completed in a mean time of 248 minutes. No relevant method-related complications were detected. Moreover, no significant changes in blood urea nitrogen (BUN), creatinine, plasma and urinary electrolytes, or platelet count were found, even in the case of repeated procedures (two to nine times). The reinfused fluid contained a mean value of albumin of 4.7 g/dL and significant amounts of globulins and complement. The overall cost of the materials used in the procedure ($49.46) offered competitive advantages with respect to other types of frequently used methods. In conclusion, we present a safe, effective, and time- and cost-saving technique for ascites reinfusion that represents an advantageous alternative to more complicated and expensive methods or to the currently used medical therapy.

Ascites↗
PubMed1996

Undiagnosed hepatitis C virus infection in hemodialysis patients: value of HCV RNA and liver enzyme levels.

At present, routine screening for hepatitis C virus (HCV) infection is based on the detection of antiviral antibodies. Underdiagnosis of HCV infection by using HCV antibody tests, however, still occurs. Additional diagnostic means are provided by the polymerase chain reaction (PCR). The measurement of aminotransferase (ASAT and ALAT) has served as an auxiliary, less specific test. The present research aimed to design practical and low cost strategies to diminish underdiagnosis of HCV infection in dialysis patients. With this purpose in mind, we examined whether aminotransferases values in HCV antibody-negative patients could be related to undiagnosed HCV infection, by using HCV RNA testing by PCR as the gold standard. In 112 hemodialysis patients, we found 78 negative and 34 positive for HCV antibodies. A major finding was that 222 (28.2%) out of the 78 HCV antibodies-negative patients had positive HCV RNA by PCR. In repeated samples taken at six months follow-up from 19 out of these 22 patients, only one of them was positive for anti-HCV antibodies; moreover, a positive HCV RNA by PCR was confirmed in 13 (68.5%) of them. Within the HCV antibody-negative group, the mean values of ASAT, ALAT and gammaglutamiltransferase were higher (P < 0.001, P < 0.001 and P < 0.02, respectively) in the HCV PCR-positive versus the HCV PCR-negative patients. No significant differences were found in the liver enzyme values between the HCV antibody-negative, HCV RNA positive and the HCV antibody positive, HCV RNA positive individuals. Histological samples from two HCV RNA positive, HCV antibody-negative patients disclosed the presence of a mild liver disease. In conclusion, the present study demonstrates the critical importance of HCV RNA determination by PCR in hemodialysis patients who have no detectable circulating antibodies against the HCV. Furthermore, in conditions in which PCR technology is not readily available, we have established that the existence of a moderate increase of aminotransferases is a helpful clue to detect patients with absent HCV antibodies, and might represent an useful, low cost tool for HCV screening in dialysis patients.

Adult↗
PubMed1996

Acute renal failure due to sulphadiazine crystalluria in AIDS patients.

We report two AIDS patients who developed acute renal failure while receiving sulphadiazine for cerebral toxoplasmosis. Renal ultrasound revealed diffuse bilateral echogenic shadowing material. 'Sheaves of wheat' crystals, typical of sulphadiazine crystalluria, were present in the urine. One patient required a percutaneous nephrostomy. Hydration and urine alkalinisation resulted in rapid improvement of renal function and ultrasonographic findings. Sulphadiazine-induced crystalluria and acute renal failure is increasingly frequent. Awareness of its existence may lead to prevention and early conservative treatment.

AIDS-Related Opportunistic Infections↗
PubMed1996

Relationships between plasma ferritin and aminotransferase profile in haemodialysis patients with hepatitis C virus.

BACKGROUND: HCV infection is a major complication among patients undergoing dialysis therapy throughout the world. In the years prior to the use of human recombinant erythropoietin (rHuEpo), patients undergoing haemodialysis were subjected to an excessive iron load as a consequence of frequent blood transfusions. Recent data in the non-dialysis population have shown a positive correlation between iron deposits and the severity of HCV hepatitis and between iron deposition and an impaired response to interferon therapy. METHODS: One hundred and five haemodialysis patients were studied. Every patient was screened for HCV infection by ELISA II and HCV RNA. Serum biochemistries were analysed by SMAC20. Ferritin was measured by radioimmunoassay. RESULTS: The aminotransferase levels for the HCV positive (n = 39) and negative patients (n = 66) were below the normal levels for the general population. The mean values of aminotransferases and plasma ferritin were, however, higher in the HCV-positive patients than in the HCV-negative patients. A positive correlation between aminotransferases and plasma ferritin was evident in HCV-positive patients, which was absent in the HCV-negative individuals. The histological severity of liver disease (n = 7) was, however, not statistically related with the levels of either ferritin or aminotransferases. CONCLUSION: HCV infection is a relevant variable when estimating iron deposits by measuring plasma ferritin. Accordingly, a misinterpretation of the actual amount of iron deposits may occur in HCV-positive patients, which should be taken into account at the time of planning their iron reposition therapy. On the other hand, the level of iron deposits might have a significant role in the evolution of HCV-related liver disease.

Aged↗
PubMedDate not supplied

[Can we increase phosphate removal with conventional hemodialysis?].

BACKGROUND: The aim of the present study was to investigate the effect of different dialysate buffer and glucose concentrations, membrane surface (S) bigger than 2 m2 and increased dialysate flow (Qd) in phosphate (P) removal. METHODS: A. First phase (5 patients): the following variations in dialysate composition were introduced. A: glucose 1.60 g/L, bicarbonate: 39 mEq/L, acetate 4 mEq/L, B: glucose 1.5 g/L bicarbonate 17 mEq/L, acetate 10 mEq/L; C: glucose 0, bicarbonate: 39 mEq/L, acetate 4 mEq/L; and D: glucose 0, bicarbonate 17 mEq/L, acetate 10 mEq/L. B. Second phase (14 patients): variations in S and Qd were: 1. Qd: 500 mL/min + Hemophan 2 m2, 2. Qd: 500 mL/min + Hemophan 2.6 m2, 3. Qd: 750 mL/min + Hemophan 2 m2, 4. Qd: 750 mL/min + Hemophan 2.6 m2. RESULTS: Comparing HDs performed with low bicarbonate (B and D) respect to current buffer formulations (A and C), total P removal was 997.3 (+/- 237.3) vs 882 (+/- 216.1) mg (p NS). No differences were found by grouping the sessions according to glucose concentration. There were no significant differences in total phosphate removal between the two different S or Qd. The most important predictive factor of total P removal was the initial P and 2 hours serum P concentration, and PTH concentration. CONCLUSIONS: i) Removal of P is better predicted by pre-dialysis P serum concentration; ii) P removal was not affected by the changes in bicarbonate and glucose concentration in the dialysate; iii) the increase of the dialyzer area between 2 and 2.6 m2 augments Kt/V, but without influencing P elimination; iv) a higher Qd does not determine significant differences in P removal and v) higher PTH is associated with a higher P elimination.

Adult↗