The relationship between bone marrow sideroblasts and iron deficiency in chronically hemodialyzed uremic subjects.

Bone marrow sideroblast counts were found to be persistently depressed to between 0 and 30 per cent in 24 uremic patients with residual renal tissue undergoing chronic dialysis therapy. Marrow sideroblastopenia notwithstanding, sideroblast counts in these subjects correlated well with iron balance, being respectively 6.6 +/- 0.8 (S.E.M.) per cent in iron depleted, and 18.2 +/- 1.7 per cent in iron-repleted individuals (p less than 0.0005). Following bilateral nephrectomy a persistent relative marrow sideroblastosis developed, counts reaching values of 46.5 +/- 3.1 per cent on average. It is suggested that this sideroblastosis is a response to reduced heme synthesis and reflects the iron removal function of ferritin granules within erythroid cells.