Severe iron deficiency causing loss of ring sideroblasts.

A patient with primary sideroblastic anaemia was observed for more than 10 years with 50% ring sideroblasts in the bone marrow and a Hb of 84-109 g/l. Iron deficiency then developed with loss of stainable iron in marrow particles (reticuloendothelial iron) and loss of all ring sideroblasts. When iron tablets had brought the iron stores in the bone marrow up to subnormal levels, the Hb was over 110 g/l, somewhat higher than it had been when the iron stores were increased. The ring sideroblasts were again raised to more than 50%.