Table 2.

“Red Flags” - signs and symptoms suggestive of clonal myeloid or mast cell disease

• Lymphadenopathy

• Hepatosplenomegaly

• CBC abnormalities

– thrombocytopenia

– anemia

– pancytopenia

– polycythemia

– neutrophilia

– hypereosinophilia (AEC >1500 cells/μL)

• Eosinophilic tissue infiltration and/or inflammation

• Anaphylaxis

– idiopathic

– venom

– severe reactions with syncope and/or hemodynamic instability

• Urticaria pigmentosa / Darier’s sign

• Premature osteopenia/osteoporosis or pathological fracture

• BST discordant with TPSAB1 copy number*

^*Each additional TPSAB1 copy number encoding α-tryptase increases BST by approximately 9–10 ng/mL, but definitely cut-offs for discordance have not yet been established; AEC – absolute eosinophil count; BST – basal serum tryptase.