RESUMEN
BACKGROUND/AIMS: Dialysis membrane has been implicated in selenium (Se) deficiency in hemodialysis (HD). Intradialytic Se removal into dialysate through different membranes was investigated. METHODS: We studied 19 patients on standard HD with low-flux polysulfone membrane (group A), 10 patients on standard HD with ethylene vinyl alcohol membrane (group B), 12 patients on hemodiafiltration (HDF; group C) and 16 healthy subjects (control group D). Se was measured in blood before and after dialysis session and in effluent dialysate every hour during session. RESULTS: In all patients together, pre-dialysis serum Se levels were lower than those in control group, but, in a separate analysis, only in standard HD. In all patient groups, there was a net Se removal into dialysate but it was greater in HDF patients who, however, had similar pre-dialysis serum Se levels to those in healthy controls. CONCLUSION: An intradialytic Se loss was found with all 3 membrane types, but it is not the principal factor for Se depletion in HD.
Asunto(s)
Anuria/terapia , Soluciones para Diálisis/química , Diálisis Renal/instrumentación , Selenio/deficiencia , Adulto , Anciano , Anciano de 80 o más Años , Anuria/sangre , Anuria/patología , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Membranas Artificiales , Persona de Mediana Edad , Polímeros/química , Polivinilos/química , Selenio/aislamiento & purificación , Sulfonas/químicaRESUMEN
BACKGROUND: Optimal dialysate calcium concentration (DCa) has not been determined under less hypercalcemic vitamin D analogues and Ca-free phosphate (P) binders. METHODS: Twelve hyperparathyroidic hemodialysis patients under sevelamer hydrochloride were treated with paricalcitol in three periods (A, B and C) under DCa of 3.5, 3 and 2.5 mEq/l, respectively, in a 3-way open-label randomized crossover study. RESULTS: Serum parathyroid hormone decreased in all periods. Under DCa = 2.5 mEq/l, there was a need for longer treatment duration, higher paricalcitol doses and increased sevelamer doses for higher serum P levels. No differences in serum Ca were observed. Ca x P values followed P changes. Episodes of Ca x P >55 mg(2)/dl(2) were more frequent in the C period. CONCLUSIONS: Under paricalcitol and sevelamer, serum parathyroid hormone decreased without Ca increase under any DCa. DCa of 2.5 mEq/l resulted in higher paricalcitol doses, increased serum P levels and more frequent high Ca x P episodes and may not be optimal with the new medications.
Asunto(s)
Calcio/administración & dosificación , Ergocalciferoles/uso terapéutico , Poliaminas/uso terapéutico , Adulto , Anciano , Calcio/uso terapéutico , Soluciones para Diálisis/uso terapéutico , Femenino , Humanos , Hiperparatiroidismo Secundario/tratamiento farmacológico , Fallo Renal Crónico/complicaciones , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Diálisis Renal , SevelamerRESUMEN
Sevelamer hydrochloride use in hemodialysis patients is complicated by metabolic acidosis aggravation and hyperkalemia. Rare reports about a short-term correction of this complication have been published. The current authors investigated the long-term correction of metabolic acidosis and hyperkalemia in sevelamer hydrochloride-treated patients at doses adequate to achieve serum phosphate levels within K/DOQI recommendations. The authors followed 20 hemodialysis patients for 24 months in an open-label prospective study. The dialysate bicarbonate concentration was increased stepwise to a maximum 40 mEq/L and adjusted to reach patient serum bicarbonate levels of 22 mEq/L, according to K/DOQI recommendations. Laboratory results for serum bicarbonate, potassium, calcium, phosphate, albumin, alkaline phosphatase, iPTH, cholesterol (HDL-LDL), triglycerides, Kt/V, systolic-diastolic arterial pressure were recorded. Sevelamer hydrochloride-induced metabolic acidosis aggravation and hyperkalemia in hemodialysis patients were corrected, on the long-term, by an increase in dialysate bicarbonate concentration. Further improvement in bone biochemistry was noted with this adequate acidosis correction and parallel sevelamer hydrochloride administration, in sufficiently large doses to achieve K/DOQI phosphate recommendations.
Asunto(s)
Acidosis/terapia , Bicarbonatos/análisis , Soluciones para Diálisis/análisis , Hiperpotasemia/terapia , Fosfatos/metabolismo , Poliaminas/efectos adversos , Diálisis Renal , Acidosis/sangre , Adulto , Anciano , Anciano de 80 o más Años , Bicarbonatos/sangre , Calcio/sangre , Femenino , Humanos , Hiperpotasemia/sangre , Masculino , Persona de Mediana Edad , Hormona Paratiroidea/sangre , Fosfatos/sangre , Potasio/sangre , Estudios Prospectivos , SevelamerRESUMEN
Reports on acid-base side effects of sevelamer hydrochloride (SH), a new aluminum (Al)- and calcium (Ca)-free phosphate binder are rare and conflicting. In a retrospective analysis, we evaluated SH impact on metabolic acidosis and serum potassium (K) in hemodialysis (HD) patients. Two groups of stable HD patients were studied. Group A included 17 patients, M/F=15/2, 64 (42-80) years old, dialyzed since 130 (34-253) months, under SH for 24 months. Group B serving as controls was made of 7 patients, M/F=4/3, 67 (48-91) years old, dialyzed since 67 (27-174) months, under CaCO3 and/or Al(OH)3 as phosphate binders also for 24 months. Bicarbonate (BIC), K, Ca, phosphorus (P), Ca x P, alkaline phosphatase (ALP), and intact parathyroid hormone (iPTH) were recorded before (MO) and at the end (M24) of 24-month SH or CaCO3-Al(OH)3 treatment in group A and B patients. In group A, BIC fell from 20.02 +/- 1.43 to 17.89 +/- 2.30 mEq/ L, P=.002; and K rose from 5.45 +/- 0.51 to 5.75 +/- 0.49 mEq/L, P=0.02. In group B, BIC (19.8 +/- 3.03 to 19.0 +/- 3.3 mEq/L) and K (5.01 +/- 0.8 to 4.9 +/- 1.1 mEq/L) had nonsignificant changes. In group A, iPTH rose from 132.82 +/- 124.08 to 326.89 +/- 283.91 pg/mL, P=.0008; P fell from 5.92 +/- 1.48 to 4.9 +/- 1.01, P=.02; and Ca x P decreased from 52.04 +/- 9.7 to 45.58 +/- 10.42 mg2/dL2, P=.04. In group B, changes in iPTH from 240.71 +/- 174.7 to 318.57 +/- 260.2 pg/mL, P from 4.9 +/- 0.5 to 4.8 +/- 1.3 mg/dL, and CaxP product from 44.3 +/- 6.6 to 44 +/- 11.2 mg2/dL2 were nonsignificant. The changes observed in Ca and ALP in both groups were nonsignificant. Correlations in group A between metabolic acidosis (BIC) and SH doses, or iPTH and BIC, Ca, or P changes, were also found to be nonsignificant. Long-term use of SH, effectively controlling serum P levels and Ca x P values, is associated with acidosis aggravation and hyperkaliemia. Worsening of secondary hyperparathyroidism, also noted, needs to be confirmed and could be related to Ca/Al salt discontinuation and to metabolic acidosis aggravation itself.