6: WBCs, LNs, Spleen, Thymus

Question 1

NK Cell two markers

Answer 1

CD16, CD56

Question 2

Early myeloblast marker vs early lymphoblast marker

Answer 2

Myeloblast: CD34

Lympho last: TdT

Question 3

Leukocyte common antigen marker

Answer 3

CD45

Question 4

Three B cell markers

Answer 4

CD19, CD20, Pax-5

Question 5

Neutropenia vs agranulocytosis

Answer 5

Neutropenia: reduced neutrophils in blood
Agranulocytosis: marked neutropenia

Question 6

Normal WBC range for blood

Answer 6

4.5-11

Question 7

Typical differential for WBCs on blood sample

Answer 7

1. 67% neutrophils
2. 27% lymphocytes
3. 4% monocytes
4. 2% eosinophils

Question 8

Absolute Neutrophil Count (ANC) equation***

Answer 8

% neutrophils + % bands x WBCs

Question 9

What ANC is seriously low

Answer 9

<500

Question 10

Examples of things that can cause severe neutropenia

Answer 10

1. Not enough made: drugs, aplastic anemia, megaloblastic anemia
2. Too much destroyed: immune destruction, hypersplenism

Question 11

What happens as a result of severe neutropenia

Answer 11

Overwhelming infections (bacterial, fungal)

Question 12

How to treat febrile neutropenic pts

Answer 12

Abx + G-CSF

Question 13

4 Causes of Leukocytosis and examples of them

Answer 13

1. Increased marrow production: chronic inflammation, paraneoplasm, myeloproliferative neoplasms
2. Increased release from marrow store: acute/chronic inflammation
3. Decreased margination: exercise, catecholamines
4. Decreased extravasation into tissues: glucocorticoids

Question 14

Major causes of the five types of leukocytosis (based on WBC)

Answer 14

1. Neutrophilic: acute bacterial infection
2. Eosinophilic: asthma, parasites, drug reactions
3. Basophilic: rare, neoplasm
4. Monocytosis: random infection/inflammation
5. Lymphocytosis: viral infections

Question 15

Acute suppurative lymphadenitis

Answer 15

Painful, fluctuant lymphadenitis with pus due to pyogenic organisms + prominent neutrophilic infiltrates

Question 16

Sinus histiocytosis

Answer 16

Increased macrophages in LN sinuses seen in many conditions (malignancy, draining foreign material)

Question 17

Three major contributors to white cell neoplasia

Answer 17

1. Genetic mutations (proto-oncogenes)
2. Viral infection (HTLV-1, EBC, HHV-8)
3. Chronic infection (H pylori)

Question 18

Leukemia vs lymphoma

Answer 18

Leukemia: blood/bone marrow neoplasia
Lymphoma: LN neoplasia

Question 19

What causes fever, fatigue, cruising, pain, and HA in ALL?

Answer 19

1. Fever: opportunistic infection
2. Fatigue: anemia
3. Bleeding/bruising: no platelets
4. Pain: expansion of cells
5. HA: goes to the meninges

Question 20

What is BCL-2?

Answer 20

Apoptosis suppressor

Question 21

How to demonstrate clonality and light chain restriction in B cell clonal neoplasms?

Answer 21

Flow cytometry

Question 22

What does MGUS stand for?

Answer 22

Monoclonal gammopathy of undetermined significance

Question 23

What does protein electrophoresis do

Answer 23

Separate proteins according to charge

Question 24

Two light chains in Abs

Answer 24

Kappa, lambda

Question 25

What does the CRAB criteria help diagnose?**

Answer 25

Myeloma

Question 26

Explain renal insufficiency in myeloma

Answer 26

Igs are filtered through -> clog tubes and damage tubular ep + create Bence-Jones proteins + systemic AL amyloidosis (light chain amyloids)

Question 27

What does urine look like in renal insufficiency in myeloma

Answer 27

Proteinuria due to light chains spilled into urine

Question 28

Three causes of anemia in CRAB criteria in myeloma

Answer 28

1. Marrow infiltration of myeloma 2. IL-6 and other cytokines 3. Renal disease / decreased EPO

Question 29

LNs involves in Hodgkin vs Non-Hodgkin lymphoma

Answer 29

Hodgkin: more localized, orderly spread, extranodal presentation is rare Non-Hodgkin: multiple peripheral nodes, noncontiguous spread, extranodal presentation common

Question 30

How do we Dx ALL, B cell NHL, and myelomas vs Hodgkin Lymphoma

Answer 30

ALL, BCNHL, Myeloma: morphology, staining, flow cytometry | HL: morphology and staining**

Question 31

Why is Hodgkin lymphoma not great with flow cytometry

Answer 31

Cells that are neoplastic clones are too diluted by other cells

Question 32

Aleukemic leukemia

Answer 32

Nothing in peripheral blood

Question 33

Mechanism of AML with t(8;21) genetic feature

Answer 33

RUNX1-RUNX1T1 fusion -> disrupts core binding factors in hematopoeitic differentiation

Question 34

Translocation and mechanism in Acute Promyelocytic Leukemia

Answer 34

PML/RARa translocation -> RAR does not want RA anymore -> differentiation stalls -> accumulation of leukemic blasts

Question 35

How to treat Acute Promylelocytic Leukemia

Answer 35

All-trans RA that the RAR will actually accept

Question 36

Some unusual presentations of AML

Answer 36

ST mass formation, granulocytic sarcoma/myeloid sarcoma/Chloroma (greenish tumors)

Question 37

RAEB II

Answer 37

Refractory anemia with excess blasts II, found in myelodysplastic syndrome

Question 38

Four types of myeloproliferative neoplasms

Answer 38

1. Chronic myeloid leukemia 2. Polycythemia Vera 3. Essential thrombocythemia 4. Primary myelofibrosis

Question 39

Eosinophilic granuloma

Answer 39

Eosinophils predominating in a unisystem LCH

Question 40

Functions of the spleen

Answer 40

1. Phagocytosis 2. Ab production 3. Hematopoeisis 4. Sequestration of blood cells

Question 41

Two causes of splenomegaly

Answer 41

1. Reactive splenitis due to viral infection | 2. Congestive splenomegaly: due to hepatic dysfunction

Question 42

What does hypersplenism cause

Answer 42

Cytopenias

Question 43

ITP: idiopathic thrombocytopenic purpura

Answer 43

Platelets are opsonized, spleen clears them

Question 44

Two big causes of splenic rupture

Answer 44

Trauma, mononucleosis

Question 45

Type of malignancy that most commonly causes splenic neoplasia

Answer 45

Hematologic malignancies

Question 46

Two major causes of splenic infarct

Answer 46

1. Outgrows its vascular supply | 2. Clog, like in sickle cell (cause it has no collaterals, just one A and V)

Question 47

Three major pathologies of the thymus to know

Answer 47

1. Thymic hyperplasia 2. Thymoma 3. Myasthenia gravis

Question 48

Myasthenia gravis

Answer 48

Auto-Abs produced in either thymic hyperplasia or thymoma

Question 49

What organism is it important to look out for in neutropenic fever

Answer 49

Pseudomonas aeruginosa

Question 50

How does DIC start from APL

Answer 50

APL leukemic cells display tissue factor on surface -> starts coagulation cascade -> lots of clots