The body is working hard, so LAP is High.
What is Leukemoid Reaction (Infection)?
Characterized by a rapid onset and a maturation block, leading to $>30\%$ blasts (FAB) or $>20\%$ blasts (WHO) in the bone marrow
What is Acute Leukemias?
Minimal maturation (rare Auer rods) & < or equal to 3% Positive MPO/SBB
What is M1?
"Foamy" macrophages
What is Niemann-Pick?
Primarily adults; pleomorphic cells.
What is L2 (Large Heterogeneous)?
The cells are "broken," so LAP is Low.
What is CML (Leukemia)?
Characterized by a slow onset and gradual proliferation where cells are still able to mature, resulting in $<10\%$ blasts
What is Chronic Leukemias?
Promyelocytic; t(15;17); DIC risk & Strong MPO; Auer rod clumps
What is M3?
Megakaryocytic; "Dry Tap" marrow & Positive Platelet Peroxidase
What is M7?
TdT is positive in ALL but negative in AML.
What is Universal Marker?
Large Dohle-like bodies and giant platelets
What is May-Hegglin?
Most common in older adults & Morphology: "Soccer ball" chromatin and Smudge Cells.
What is CLL (Chronic Lymphocytic)?
Undifferentiated (no granules) & All Negative (MPO, SBB, NSE)
Monocytic (M5a: Blasts; M5b: Mature) & Strongly Positive NSE
What is M5?
Primarily childhood leukemia; best prognosis
What is L1 (Small Homogenous)?
Large, dark purple granules (lipids) in all leukocytes.
What is Alder-Reilly?
Morphology: Cells with "hairy" cytoplasmic projections & Lab Hack: TRAP stain POSITIVE.
What is Hairy Cell Leukemia?
Myelomonocytic (Myelo + Mono) & Positive MPO & NSE
What is M4?
Giant lysosomal granules; affects chemotaxis/killing
What is Chediak-Higashi?
Large cells with prominent vacuolization and deep basophilic cytoplasm
What is L3 (Burkitt’s Type)?
Hyposegmented nucleus (Pince-nez appearance).
What is Pelger-Huet?
Defined by the Philadelphia Chromosome t(9;22).
What is CML (Chronic Myeloid)?
Most common; full maturation & Strongly Positive MPO/SBB
What is M2?
Erythroleukemia (>50% nRBCs) & Positive PAS (block-like)
What is M6?
Crinkled paper" or "onion skin" cytoplasm in macrophages.
What is Gaucher’s Disease?