Aggressive systemic mastocytosis (ASM)

The marrow aspirate smear is normocellular with an elevated number of mast cells; there are also a few erythroid precursors, as well as granulocytes and their precursors.

This picture of marrow aspirate smear shows mast cells with round or oval nuclei with clumped chromatin, a low nuclear/cytoplasmic ratio and indistict nucleoli; abundant cytoplasm is packed with deep purple granules. Some of the mast cells are broken.

Staining of marrow aspirate smear with toluidine blue reveals metachromatic mast cells granules and a few basophils.