Manejo de la eritropoyetina humana recombinante en pacientes con enfermedad renal crónica en estadio IV

Abstract

IntroductionAdministration of recombinant human erythropoietin (r-HuEpo) in patients with anemia due to chronic renal failure (CRF) produces clinical improvement with a consequent reduction in morbidity and mortality. ObjectiveTo determine the required dose of rHuEpo to achieve a hemoglobin level of 11 to 12g/dl and hematocrit between 33% and 36% in predialysis patients with chronic renal failure in a Mexican population. Patients and methodsWe performed a prospective open analysis of 16 predialysis adult patients. A complete clinical history and examination was performed in all patients, as well as laboratory tests, which included a complete blood cell count, blood chemistry, serum electrolytes, functional liver tests, creatinine clearance and iron kinetics, obtained at 2, 4, 8 and 12 weeks. Blood pressure was measured daily for the 12 weeks of the study. r-HuEpo was administered subcutaneously with a first dose of 50UI/kg/week, increasing to 75UI/kg/week in the fourth week in all patients whose hemoglobin had increased less than 1g/dl. All patients received ferrous sulphate 200mg once daily throughout the study period. Patients with serum ion values below 40mcg/dl and a saturation index of less than 20% received ferrous sulphate 300mg orally, divided in two or three doses. Folic acid and vitamin B12 quantifications were also obtained at the beginning and end of the study. The statistical method applied was analysis of variance (ANOVA), descriptive statistics and p-values to determine statistical significance. ResultsSixteen patients were included, five men and 11 women, with a mean age of 42 years (range: 16 to 60). The cause of CRF was chronic glomerulonephritis in six patients (37.5%), lupus nephropathy in one (6.25%), polycystic kidney disease in one (6.25%), diabetic nephropathy in five (31%), tubulointerstitial nephritis in two (13%) and nephrosclerosis in one (6.35%). At study completion, hemoglobin levels had increased to 3.1 g/dl (P<.00001) and hematocrit to 5.5% (P<.000001). The dosage required was 50UI/kg/week in 12 patients (75%) and 75UI/kg/week in four patients (25%). Blood pressure measurements remained stable; two patients (12.5%) had mild hypertension, requiring adjustment of antihypertensive medication, and one patient (6.25%) had headache. ConclusionsThe dosage required to achieve the hematocrit and hemoglobin values recommended by the National Kidney Foundation Disease Outcomes Quality Initiative (NKF-DOQI) was 50 to 75UI/kg/week in predialysis patients. No significant changes were observed in blood pressure, side effects were minimal, and residual renal function remained stable.