H Ii: Intro To Leukemia And Cytochemical Stains (Sw E3 1/5)

Front 1

Leukemia - definition

Back 1

-Cancer (Malignancy) of blood and blood forming tissues

-Uncontrolled cell proliferation: too many cells

-Abnormal function: cells don’t work

Front 2

Leukemia - outcomes

Back 2

-Immunosuppression: severe, life threatening infections

-Imbalanced hemostasis: hemorrhage

-Decreased oxygen carrying capacity: anemia, tissue death, organ failure

Front 3

Time of Onset (Classifications)

Back 3

-Acute: rapid, progressively worsening clinical course

-Chronic: indolent clinical course

Front 4

Cell maturation (Classifications)

Back 4

-Acute: proliferation of immature cells: “arrested maturation”

-Chronic: proliferation of mature looking cells: “normal maturation”

Front 5

Leukemia - symptoms

Back 5

-Anemia

-Thrombocytopenia: bleeding

-Neutropenia: infections

-Bone pain: expansion of marrow

-Weightloss

-Hepatosplenomegaly

-Lymphadenopathy

-Rashes/tumors/CNS involvement – tissue infiltrates of neoplastic cells (chloromas or myeloid tumor)

Front 6

Acute leukemia - lab results

Back 6

-Decr to mod incr WBC

-N to decr PLTs

-Abnormal morphology: Large, hypogranular, micromegakaryocytes

Front 7

Chronic leukemia - lab results

Back 7

-Incr to markedly incr WBC

-N to incr PLTs

-Anemia

Front 8

Peroxidase - Myeloperoxidase (MPO) - principle

Back 8

-Peroxidase in granules in myelocytic and monocytic cell lines

-Most strongly in myelocytic cells

-Peroxidase + H2O2 oxidizes a dye substrate creating a black/blue/brown ppt

-Differentiates AML vs ALL

Front 9

Myeloperoxidase - interpretation

Back 9

-Evaluate blasts only

-Stains Primary

Granules

-neutrophils

-eosinophils

-monocytes

-stain = Acute Myeloid Leukemias

-no stain = Acute Lymphoid Leukemias

Front 10

Back 10

MPO stain smear

Front 11

Back 11

MPO stain smear

Front 12

Sudan Black B (SBB) - principle

Back 12

-Stains lipids such as sterols, neutral fats & phospholipids

-found in granules of neutrophils & monocytes

-Differentiates AML vs ALL

Front 13

Sudan Black B (SBB) - interpretation

Back 13

-Consider blasts only

-AML will see incr staining of myelocytic and monocytic blasts

Front 14

Back 14

Sudan Black B smear

Front 15

Back 15

Sudan Black B smear

Front 16

Esterases - principle

Back 16

-hydrolyze an ester substrate

-A napthol compound is released and combines with a diazonium salt that ppts

Front 17

Specific Esterase - general

Back 17

-napthol AS-D chloroacetate

-granulocyte esterase

-myelocytic blasts will stain

---primary granules

---auer rods

Front 18

Nonspecific Esterase (NSE) - general

Back 18

-Alpha-napthyl acetate or alpha-napthyl butyrate

-Monocytic cells are strongly pos, & inhibited w/ NaF

-Myelocytic cells may be weakly pos, & remains weakly pos w/ NaF

Front 19

Combined Esterase - general

Back 19

-Combines specific and nonspecific in one dye (Not commonly used)

Front 20

Periodic Acid Schiff (PAS) - principle

Back 20

-Acid oxidizes glycogen, mucoproteins & other high molecular wt. carbs to aldehydes

-Aldehydes react w/ Schiff rgt staining bright pink

-Positive rxn in malignant lymphocytic & erythrocytic cells (chunky or blocky)

-Negative in benign cells

-Megakaryocytes will also stain, but diffuse

Front 21

Leukocyte Alkaline Phosphatase (LAP) - principle

Back 21

-In secondary granules of neutrophils

-Substrate: napthol AS-BI phosphate is hydrolyzed by LAP

-Hydrolyzed substrate combines w/ a dye & precipitates (color depends on substrate used)

Front 22

LAP - interpretation

Back 22

-Score 100 PMNs and Bands on a scale of 0 - 4+ based on the amount of ppt in the cell

-Used to Investigate a shift to the left

-Malignant granulocytes (CML): Decr LAP vs. leukomoid rxn (incr LAP)

-Other causes of decreased LAP: PNH, Sideroblastic anemia, Myeloproliferative disorders

-CML will have REDUCED score

Front 23

Back 23

LAP scale

Front 24

Back 24

LAP reactions

Front 25

Tartrate Resistant Acid Phosphatase (TRAP) - principle

Back 25

-present in almost all nonerythroid cells

-hydrolyzes substrate napthol AS-BI phosphoric acid

-Hydrolyzed substrate couples w/ a dye to form a red ppt

-All normal isoenzymes of the enzyme are inactivated by tartaric acid and will not stain.

-In Hairy Cell Leukemia isoenzyme #5 is resistant to tartaric acid and will stain

Front 26

Terminal deoxyribonucleotidal Transferase (TdT) - principle

Back 26

-A specific cell marker (enzyme) that catalyzes the polymerization of deoxynucleotides found only in lymphocytic precursors. Absent in lymphocytes

-Not a cytochemical stain: is an immunofluorescent stain (flow cytometry) or immunoperoxidase technique

Front 27

TdT - interpretation

Back 27

-Positive in acute lymphocytic leukemias ( L1 & L2 )

-Must interpret carefully: TdT has been observed in AML