Abnormal WBCs and Leukemia Flashcards
Diapedesis
Passage of blood cells through intact capillary walls, usually accompanying inflammation
T Cell Markers
Tdt, CD4, CD8
B Cell Markers
Surface Ig, CD34, CD19
Hypersegmentation occurs in
megaloblastic anemia or in response to infection
Hyposegmentation occurs in
Pelger Huet Anomaly, Myeloproliferative Disorder (MPS) or Myelodysplastic Disorder (MDS)
Dohle Bodies
Light blue granular inclusions, which are aggregates of ER (RNA), associated with infection and May-Hegglin anomaly
Auer Rods
Red or orange needle-like inclusions, made of fused lysosomes. Associated with myelocytic leukemia
Russell Bodies
“Flame Cells” (stark cytoplasmic color gradient) and “Mott Cells” (extreme vacuolation)
Barr Bodies
“Drumstick” (tiny nuclear lobe) inclusions made of inactive X chromosomes. Seen in females and Klinefelters syndrome patients
Leukemoid Reaction
Leukemia-like response to chronic infection. Severe left-shift, usually >25 x10^9/L neutrophils. Distinguished with high LAP score, toxic granulation, and Dohle Bodies from Chronic Myelogenous Leukemia (CML).
Marginated Granulocyte Pool (MGP)
Neutrophils that are stuck to the inside of the vascular system and don’t come out w/ peripheral blood. Can cause pseudoneutropenia.
Chronic Granulomatous Disease
Rare, inherited. Abnormal oxidative metabolism in neutrophils. Results in frequent infections. Test with Nitroblue tetrazolium (NBT)
Chediak Higashi Anomaly
Rare, inherited. Usually fatal in infancy due to infection. Large, dark blue inclusions. Fusion of primary and secondary granules in neutrophils = abnormal lysosomes. Affects cell locomotion, de-granulation, and killing potential
May-Hegglin Anomaly
Rare, inherited. Large, round, pale blue inclusions. Associated with thrombocytopenia, giant platelets, bleeding.
Pyknotic Nucleus
Hyper-dense (almost black) nuclei. Indicates a cell part-way through apoptosis.
Pelger-Huet Anomaly
Benign inherited. “Pince nez” neutrophils, which function normally.
Alder-Reilly Anomaly
Large purple granules in WBC cytoplasm (looks like toxic gran but can be in lymphs). Caused by enzyme deficiency, but cells function normally.
Leukocyte Adhesion Deficiency
Rare, inherited. Absence of surface adhesion proteins on WBCs (integrins). High mortality rate from frequent infections.
Gaucher’s Disease
Lipid Storage Disorder. Deficiency of Glucocerebrosidase. Causes “tissue paper cell” with eccentric nucleus and “crinkly” looking cytoplasm
Nieman Pick Disease
Lipid Storage Disorder. Deficiency of sphingomyelinase. Causes “foamy” macrophages with tons of fat vacuoles. Often fatal by age 3.
Tay-Sachs Disease
Lipid Storage Disorder. Deficiency of B-hexoseamidase. Glycolipids and mucopolysaccharides in CNS. Often fatal by age 4.
Sea Blue Histiocyte Syndrome
Lipid Storage Disorder. Sea Blue staining of macrophages in spleen and marrow. Splenomegaly and decreased platelets. Usually benign.
Wiskott-Aldrich Syndrome
Normal B cell count, abnormal B cell function. Decreased antibody production.
DiGeorge Syndrome
Decreased T cells and Lymphoid tissue, normal B cells. Missing or dysfunctional thymus.
Dutcher Bodies
Vacuole-like inclusions in the nucleus of plasma cells, associated with multiple myeloma
Myeloproliferative Neoplasms (MPN) Symptoms and examples
- Increased RBC, WBC, PLTs
- Includes: Chronic Myelogenous Leukemia (CML), Chronic Neutrophilic Leukemia (CNL), Essential Thrombocythemia (ET), Polycythemia Vera (PV), Primary Myelofibrosis (PMF)
What mutation is most commonly associated with CML?
BCR-ABL1, aka the “Philadelphia Chromasome”, translocation between 9 and 22
CML Laboratory Presentation
- VERY high WBC count (200-500k)
- Left shift to blasts, no leukemic hiatus
- Increased Eos/Basos
- N/N Anemia
- Increased PLT
- Low LAP stain
CNL Laboratory Presentation
- Neutrophilia
- Slight left shift
- No BCR/ABL1 (Phili chromosome)
- RBCs and PLT Normal
- High LAP stain
ET Laboratory Presentation
- PLT > 1,000,000/cumm
- Abnormal appearance and function of PLT
- Increased WBCs
- JAK2 Mutation
Polycythemia Vera (PV) etiology
RBC clonal stem cell defect allows proliferation without need for EPO
PV Laboratory Presentation
- Increased RBCs (N/N, sludging)
- HGB >18g/dL
- Increased WBC and PLT
- Increased LAP
- Often a JAK2 Mutation
Relative Polycythemia
Increased HCT due to decreased plasma volume
Primary Myelofibrosis Etiology
Fibrotic tissue replaces cellular mass of the marrow
PMF Laboratory Presentation
- N/N Anemia
- nRBCs
- Teardrop cells
- Anisocytosis/poikilocytosis
- Increased WBC w/ left shift and eos/basos
- Decreased PLT
Myelofibrosis vs. Myelophithisic Anemia
- High vs low WBCs
- Fibrotic vs tumor cells in marrow
Chronic Eosinophilic Leukemia (CEL)
- Increased WBC
- N/N Anemia
- Low PLT
- Lots of Eos w/ left shift of Eos
Basophilic Leukemia (BL)
- Increased WBC
- N/N Anemia
- Decreased PLT
- Lots of Basos w/ left shift of Basos
Myelodysplastic Syndrome (MDS) Etiology
- Abnormal maturation (dysplasia) in bone marrow
- Activated oncogenes
- Loss of tumor suppressor genes
- Epigenetic and chromosome damage
Mutations associated with MDS
- Proto-oncogenes: JAK2, RAS, RUNX1
- Tumor suppressor: TP53
MDS Laboratory Presentation
- Anemia (Macrocytes, dimorphic, basophilic stippling, H-J bodies)
- Neutropenia w/ hyposegs and hypogran
- Dysplasia in one or more cell lines
- Increased Monos
- Decreased T cells
MDS vs Megaloblastic Anemia
B12/Folate normal vs Low
Myeloperoxidase (MPO) Stain
Myeloid cells (Neutrophils and precursors, Eos, Monos)
Sudan Black B (SBB) Stain
Strong on Granulocytes, Weak on Monos, Negative on Lymphs
Chloroacetate Esterase (Specific Esterase) Stain
Granulocytes and mast cells
Alpha Napthyl Esterase (Non-specific Esterase) Stain
Monocytes and myelomonocytes
Periodic Acid Schiff (PAS) Stain
Glycogen, Strong positive in M6 ALL
Tartrate Resistant Acid Phosphatase (TRAP) Stain
Hairy cells
Terminal Deoxynucleotidyl Transferase (TDT) Stain
Immature lymphs, especially T cells
Toluidine Blue Stain
Basophils and mast cells
Leukocyte Alkaline Phosphatase (LAP) Stain
- Strong in reactive myelocytes (Leukamoid reaction, PV, MM, PMF)
- Weak in CML, PNH, sideroblastic anemia
Difference between leukemia and lymphoma
Leukemia starts in the blood and bone marrow, lymphoma starts in the tissue (usually lymph). They often turn into each other as they progress.
What marker is used to identify immature T and B cells?
CD34
Common T cell markers
CD2, CD3, CD5, CD7
Common B cell markers
CD19, CD22
Categories of Acute Lymphoblastic Leukemia (ALL)
WHO:
- B cell ALL (most common)
- T cell ALL
FAB:
- L1-L3
ALL Laboratory Presentation
- N/N Anemia
- Decreased PLT
- Blasts (no Auer rods) with hiatus
- Variable WBC count
Lymphoblastic Lymphoma (LBL)
B or T cell neoplasm without bone marrow involvement
FISH Testing
Fluorescent In-Situ Hybridization. Detects chromosomal abnormalities.
CLL Laboratory Presentation
- N/N Anemia
- Decreased PLT
- Decreased Neutrophils
- Increased WBC
- Increased Lymphs
- Smudge Cells!!
Hairy Cell Leukemia Laboratory Presentation
- Pancytopenia
- Hairy Cells (confirm with TRAP stain)
- Fibrosis in bone marrow
Multiple Myeloma Etiology
Malignant proliferation of plasma cells. Monoclonal gammopathy (mostly IgG).
Multiple Myeloma Laboratory Presenation
- +++ plasma cells in bone marrow
- Abnormal plasma cells (flame cells, Dutcher bodies, mott cells with Russel bodies)
- Monoclonal (M spike) on electrophoresis
- Bence Jones protein in urine
- Rouleaux!!
Sezary Syndrome
- T cell lymphoma
- T helper cells with irregular nuclear outline and fine chromatin (clefts and folds)
Hodgkin’s Lymphoma
- Orderly progression in the lymph nodes
- “Owl eye” cells in lymph nodes
- Does not enter peripheral blood
- Central lymph nodes
- “Staging” used to treat
Non-Hodgkin’s Lymphoma
- Disorderly progression, jumping around
- “normal” appearance of cells in lymph nodes
- Can enter peripheral blood
- Peripheral lymph nodes
- “Grading” used to treat
Lymph Node Structure
- B cells in follicles of cortex
- T cells in paracortex
- Macrophages in sinuses
Burkitt’s point mutation
8,14 translocation, associated with Non-Hodgkin’s Lymphoma
Staging of Hodgkin’s Lymphoma
Stage I - 1 node
Stage II - >1 node, same side of diaphragm
Stage III - >1 node, both sides of diaphragm
Stage IV - disseminated disease
Which Acute Leukemia is most common in children?
ALL
AML Laboratory Presentation
- N/N Anemia
- Decreased PLT
- Variable WBC
- Blasts with Auer rods
- Leukemic hiatus
FAB vs WHO classification of acute leukemia
FAB: >30% blasts in bone marrow
WHO: >20% blasts in bone marrow
FAB categories of AML
M0-M7
M0
“Minimal differentiation”
- 90% blasts
Positive for:
- MPO/SBB (<3%)
- Specific esterase
- PAS
Negative for:
- Non-specific esterase
M1
“Without maturation”
- 90% blasts
Positive for:
- MPO/SBB (>3%)
- Specific esterase
- PAS
Negative for:
- Non-specific esterase
M2
“With maturation”
- 30-89% blasts
- 10% promyelocytes and myelocytes
- can have Auer rods
Positive for:
- MPO/SBB
- Specific esterase
- PAS
Negative for:
- Non-specific esterase
M3
“With PML-RARA”
- >30% blasts
- Increased promyelocytes
- Auer rods
- Associated with DIC
- 15,17 translocation
Positive for:
- MPO/SBB (+++)
- Specific Esterase
- PAS
Negative for:
- Non-specific esterase
M4
“Myelomonocytic leukemia”
- >30% blasts
- Increased monocytes
Positive for:
- MPO/SBB
- Specific Esterase
- PAS
- Non-specific Esterase
M5
“Monoblastic leukemia”
- >30% blasts
- >80% monocytic lineage
Positive for:
- MPO/SBB (<20%)
- Specific Esterase
- PAS
- Non-specific Esterase (>80%)
M6
“Pure erythroid leukemia”
- Digugliemo’s Syndrome
- >30% blasts
- >50% erythroid lineage
Positive for:
- PAS
Negative for:
- MPO/SBB
- Specific Esterase
- Non-specific Esterase
M7
“Megakaryoblastic leukemia”
- >30% megakaryoblasts
- Dry tap (tons of fibrin in the marrow)
- Platelet blebbing
Positive for:
- PAS
- Acid phosphatase
Negative for:
- MPO/SBB
- Specific esterase
- Non-specific esterase
M4e
“Eosinophilic variant”
- Same appearance as M4, plus increased Eos in bone marrow
- Inversion of chromosome 16
- Eos here are Specific esterase positive (unlike normal Eos)
What are CD markers?
“Clusters of Differentiation”, a system of categorizing antigens which can be bound by antibodies produced by various companies to ensure that product names didn’t obscure what the antibodies were specific to
Markers associated with myelocytic and monocytic cells
CD13 and CD33
L1
- Small homogenous blasts with fine chromatin and no nucleoli
- Scant cytoplasm
- Most common in children
L2
- Large blasts with fine chromatin and irregular nuclei (clefts) and nucleoli
- Abundant cytoplasm
- Adults
L3
- Large cells with fine chromatin and nucleoli
- Very blue and vacuolated cytoplasm
- Burkitt’s lymphoma
Common Acute Lymphocytic Leukemia Antigen (CALLA)
CD10
T vs B Cell Cytochemical Stain
T cells - Acid Phosphatase Pos
B cells - Surface Immunoglobulin (sIg) Pos
9:22 Translocation
“Philadelphia Chromosome”, important CML
15:17 Translocation
Diagnostic for M3
8:21 Translocation
Better prognosis for AML