A randomized trial of iron deficiency testing strategies in hemodialysis patients

Diagnosis of iron deficiency in hemodialysis patients is limited by the inaccuracy of commonly used tests. Reticulocyte hemoglobin content (CHr) is a test that has shown promise for improved diagnosis in preliminary studies. The purpose of this study was to compare iron management guided by serum ferritin and transferrin saturation to management guided by CHr.

A total of 157 hemodialysis patients from three centers were randomized to iron management based on (group 1) serum ferritin and transferrin saturation, or (group 2) CHr. Patients were followed for six months. Treatment with intravenous iron dextran, 100 mg for 10 consecutive treatments was initiated if (group 1) serum ferritin <100 ng/mL or transferrin saturation <20%, or (group 2) CHr <29 pg.

There was no significant difference between groups in the final mean hematocrit or epoetin dose. The mean weekly dose of iron dextran was 47.7 +/- 35.5 mg in group 1 compared to 22.9 +/- 20.5 mg in group 2 (P = 0.02). The final mean serum ferritin was 399.5 +/- 247.6 ng/mL in group 1 compared to 304.7 +/- 290.6 ng/mL in group 2 (P < 0.05). There was no significant difference in final TSAT or CHr. Coefficient of variation was significantly lower for CHr than serum ferritin and transferrin saturation (3.4% vs. 43.6% and 39.5%, respectively).

CHr is a markedly more stable analyte than serum ferritin or transferrin saturation, and iron management based on CHr results in similar hematocrit and epoetin dosing while significantly reducing IV iron exposure.