Folate measurements in patients on regular hemodialysis treatment

• Published in: American journal of kidney diseases Vol. 33; no. 3; pp. 492 - 497
• Main Authors: Bamonti-Catena, Fabrizia, Buccianti, Gherardo, Porcella, Antonella, Valenti, Giovanni, Como, Giovanna, Finazzi, Silvia, Maiolo, Anna Teresa
• Format: Journal Article
• Language: English
• Published: Orlando, FL Elsevier Inc 01-03-1999; Elsevier
• Subjects: Adult; Aged; Aged, 80 and over; Anesthesia. Intensive care medicine. Transfusions. Cell therapy and gene therapy; Biological and medical sciences; Edetic Acid; Emergency and intensive care: renal failure. Dialysis management; Erythrocyte Indices; Erythrocytes - metabolism; erythropoietin; Erythropoietin - therapeutic use; Female; Folate; Folic Acid - administration & dosage; Folic Acid - blood; Folic Acid Deficiency - blood; Folic Acid Deficiency - drug therapy; Folic Acid Deficiency - etiology; Hematologic Tests - methods; hemodialysis patients; Humans; Intensive care medicine; Male; Medical sciences; Middle Aged; Recombinant Proteins; Renal Dialysis - adverse effects; Reproducibility of Results; Uremia - blood; Uremia - therapy; hemodialysis patients; Folate; erythropoietin; Human; Plasma; Biochemical analysis; Megaloblastic anemia; Erythropoietin; Hemodialysis; Indication; Deficiency; Red blood cell; Biological marker; Hemopathy; Extrarenal dialysis; Complication; Comparative study
• ISSN: 0272-6386; 1523-6838
• DOI: 10.1016/S0272-6386(99)70186-1

Patients on regular hemodialysis treatment may develop megaloblastic anemia caused by folate deficiency, but whether folate supplementation is required is still controversial, particularly during erythropoietin administration. Erythrocyte folate concentration is a better indicator of folate status than serum folate, although the latter is the variable generally measured. We measured serum and erythrocyte folate in blood samples from 112 regular hemodialysis patients (57 men, 55 women, 50 treated with erythropoietin, and 62 not) by Stratus Folate immunoenzymatic assay (Dade). Patients with very low serum (<2.87 ng/mL) but normal erythrocyte folate were reinvestigated 4 months later without receiving folate supplementation meanwhile. Serum folate concentrations were 0.48 to 12.76 ng/mL (median, 3.40) and erythrocyte folate 0.19 to 1.85 μg/mL (median, 0.42). Only 37% serum folate values were in the relevant reference interval compared with 80.2% erythrocyte folate values (3.08 to 17.65 ng/mL and 0.24 to 0.64 μg/mL, respectively). A significant correlation was found between serum and erythrocyte folate concentrations, without clinical relevance caused by the wide scatter around the regression line. Serum and erythrocyte folate did not vary significantly between patients given erythropoietin and those not so treated. The folate status of the 24 patients with very low serum folate was almost unchanged 4 months later. According to the serum folate test, 63% of patients needed folate supplementation, whereas the erythrocyte folate test, a better indicator of folate status, suggested that only 1.8% of patients needed folate supplementation. Erythropoietin therapy appears not to be an indication for standard folate supplementation in hemodialysis patients.