Cytochemistry Cytochemical properties of the leukemic<unk> s must be typical of<unk> <unk>  derivation (presence of metachromatic granules staining with alpha-naphthyl chloroacetate esterase, but not with peroxidase).<unk> <unk>  tryptase is an enzyme contained in<unk> <unk>  granules.<unk> <unk>  numbers are best estimated by tryptase immunostaining because very poorly granulated<unk> s may stain very weakly if at all for alpha-naphthol chloroacetate esterase. Tumor markers The leukemic<unk> s usually are strongly positive for CD13, CD33, CD68, and CD117. Characteristically, basophil (e.g. CD11b, CD123) and monocyte markers (CD14, CD15) are absent. The<unk> s usually express CD2 and CD25. Malignant<unk> <unk> s overexpress the anti-apoptosis gene, bcl-2. A mutation called KIT mutation is detected in most patients. Biochemistry Total serum tryptase is elevated in<unk> . Normal total (alpha + beta) serum tryptase is approximately 6 micro g/L (range 0 to 11 micro g/L). Values of several hundred micro g/L are characteristic of<unk> . Plasma and urinary histamine levels are frequently elevated in<unk> . Histidine decarboxylase (HDC) is the enzyme that catalyzes the reaction which produces histamine from histidine. Measurement of histidine carboxylase in the marrow<unk> s of patients with<unk>  is a very sensitive marker of<unk> <unk> s.
Mast cell leukemia
Leukemoid reaction
Hemophagocytic lymphohistiocytosis
Chronic eosinophilic leukemia
Acute eosinophilic leukemia
Large granular lymphocytic leukemia
Diffuse infiltrative lymphocytosis syndrome
Thymoma with immunodeficiency