V.B.001

Increased iron aggregates. Marrow. Prussian blue stain. Several macrophages engorged with iron are noted. The frequency of iron aggregates is greater than seen in normal marrow. Marrow iron is contained in two proteins: hemosiderin and ferritin. Prussian blue stains hemosiderin iron and macrophage iron is principally hemosiderin. In iron deficient states, loss of marrow storage iron in hemosiderin and ferritin is proportionately similar and thus staining for hemosiderin is a reasonable measure of storage iron.