#2 - Cytochemistry

CLASSIFICATION OF CYTOCHEMICAL STAINS

MPO differentiates → AML and ALL blasts
MPO diagnoses → neutrophil myeloperoxidase congenital deficiency
MPO identifies → primary (azurophilic) granules of monocytic and myeloid cells
MPO released from azurophilic granules catalyzes the transformation of ______ in the presence of a halogen (Cl-) into highly toxic molecules → H2O2 or Hydrogen peroxide
Positive MPO reaction → Neutrophilic granulocytes & Monocytes (except blasts), Eosinophils, Acute rods (in leukemic blasts and promyelocytes)
Negative MPO reaction → Basophil (weak +), Lymphocytic cell, Erythrocytes

ES differentiates → granulocytic leukemia from monocytic leukemia
2 substrate esters (nonspecific) commonly used →
- a-naphthyl acetate
- Positive → Monocytic Leukemia/ cells
- Its addition will inhibit esterase reaction in monocytes → Sodium Fluoride (NaCl)
- a-naphthyl butyrate
- Positive → Monocytic Leukemia/ cells
Specific substrate ester → Naphthol AS-D chloroacetate
- Positive ES → Granulocytic Leukemia/cells
- Negative ES → Monocytic Leukemia/ cells

ACP demonstrates → Lysosomes
ACP differentiates → subgroup of ALL
ACP uses what acid and dye to give maroon pigment → AS-B1 phosphoric acid and fast garnet dye
Positive reaction → Leukocyte, Monocyte > Neutrophil, T cells (golgi region)
Can be positive or negative → B cells
ACP isoenzymes are inhibited by → L-tartaric acid
TRAP → tartrate-resistant acid phosphatase for hairy cell leukemia

Smear is made from a drop of capillary or EDTA? → capillary (EDTA is inhibitory)
Color reaction: red, brown to black ppt. (cytoplasm of neutrophil)
100 mature and neutrophil bands are scored from 0 to 4+ based on stain intensity (blue)

ALP → Leukocyte ALP (LAP) Score

STAINS