General information:
The iron content assessment of a bone marrow film stained with Prussian blue is semi-quantitative, i.e., a mean estimate at 100 and 400-fold magnification.
A 4-step classification is used:
- no storage iron
- decreased storage iron
- normal storage iron
- increased storage iron
Assessment:
In the iron stain with Prussian blue, hemosiderin stains blue to blue-green and the cell constituents are red. The iron content in the bone marrow is a good indicator of the body's iron stores. In the normal iron state, coarse blue granules are found equally distributed throughout the bone marrow film. With an decreased iron storage they are more rarely seen and with no storage iron they are absent. The hemosiderin granules are densely packed with an increased iron storage.
Sideroblasts and ringed sideroblasts:
While single sideroblasts are normal in the bone marrow, ringed sideroblasts (see image) indicate a sideroblastic defect (abnormal iron metabolism).