Heme Onc

Question 1

What is the main difference in effect between unfractioned heparin and LMWH?

Answer 1

Both of them can bid to AT3 to increase its activity against factor Xa.

Only unfractionated heparin is able to bind to both AT3 and thrombin, thereby allowing antithrombin to inactivate thrombin.

Question 2

What is the most common viral cause for aplastic crisis for sickle cell patients?

Answer 2

Parvovirus B19

Question 3

What effect might fibrinolytics have on heart rhythm?

Answer 3

They may cause a repurfusion arrhythmia on arterial reopening. These arrhytmias are usually benign.

Question 4

What is the presentation for Hemolytic Uremic Syndrome? (3) What is the etiology?

Answer 4

1. Microangiopathic hemolytic anemia
2. Thrombocytopenia
3. Renal insufficiency

Result of 0157:H7 E.coli, usually in undercooked ground beef

Question 5

Hepcidin

1. What is it/ what does it do?
2. When is it released?

Answer 5

1. Hepcidin is an acute phase reactant synthesized by the liver that acts as the central regulator of iron homeostasis. It prevents release of iron bound by ferritin
2. High iron levels/ inflammatory conditions increase hepcidin synthesis. Hypoxia and increased EPO lower hepcidin levels

Question 6

What is the effect of low hepcidin levels?

Answer 6

Low hepcidin levels increase intestinal iron absorptin and stimulate iron release by macrophages

Question 7

Hairy Cell Leukemia

1. What type of neoplasm?
2. Presentation?

Answer 7

1. Indolent B-cell neoplasm
2. MIddle-aged men w/ bone marrow /fibrosis (leading to dry tap) + massive splenomegaly (due to red pulp infilitration) + cytoplasmic projections on lymphocytes

Question 8

What is the specific deficiency in patients with Glanzmann thrombasthenia?

Answer 8

(GP) IIb/IIIa, needed for platelet aggregation

Question 9

Abciximab MOA

Answer 9

It blocks the GP IIb/IIIa receptor, which normally promots platelet binding to fibrinogen

Question 10

Paroxysmal nocurnal hemoglobinuria is result of an acquired mutation in what gene? What inhibitor proteins is absent and/or deficient as a result?

Answer 10

Mutation in the PIGA gene. This leads to absence of the GPI anchor that normally protects the RBC from complement, and associated deficiency of CD55/CD59 complement inhibitor proteins.

Question 11

Dactylitis

(What is it and what is it a common presentation of?)

Answer 11

Painful swelling of the hands and feet

It is a common presentation of sickle cell in young children.

Question 12

What effect does sickling (in SCD) have on labs?

Answer 12

Leads to

1. Increased indirect bilirubin
2. Increased lactate dehydrogenase
3. Decreased haptoglobin (binds free hemoglobin and is then removed by the spleen)

Question 13

What drugs do you give to reverse heparin effects? Warfarin effects?

Answer 13

Heparin: protamine sulfate

Warfarin: Vitamin K and Fresh Frozen Plasma (FFP)

Question 14

X-linked (Bruton) agammaglobulinemia

1. Caused by what?
2. Effect on germinal center formation
3. Presentation?

Answer 14

1. Caused by a defect in B cell maturation, resulting in the absence of mature B cells with severe defiency of all Ig types. T cells remain fxnal and intact!
2. No B cells = no germinal center formation
3. Recurrent infxn in setting of intact T Lymphocyte function

Question 15

Distinguish Precursor B-ALL from precursor T-ALL

Answer 15

This can only be done via immunophenotyping

B-ALL: TdT+, CD10+ and CD19+

T-ALL: TdT+, CD1a+, and + for T-cell markers (CD2 , 3, 4, 5, 7, and 8)

Question 16

What is the role of atypical T-cells in assc. with EBV?

Answer 16

They function to destroy virally-infected B-lymphocytes

Question 17

Patients with Down Syndrome are at an increased risk for what CA types?

Answer 17

ALL and AML

Question 18

Tumor lysis syndrome

1. When can it develop?
2. What characterizes it?

Answer 18

1. Develops during chemo for CAs with rapid cell turnover, high tumor burden, or high chemo sensitivity
2. Characterized by a leak of intracellular ions (such as hyperphosphatemia, hypocalcemia, hyperkalemia, and hyperuricemia)

Question 19

Prevention of Tumor Lysis Syndrome

Answer 19

Prevent w/ hydration + use of hypouricemic agents such as allopurinol or rasburicase

Question 20

Describe the peripheral blood smear associated with lead poisoning

Answer 20

Coarse erythrocyte basophilic stippling and microcytic hypochromic anemia

Question 21

(Leukocyte Accumulation:) What receptors are involved in:

1. Rolling?
2. Tight Adhesion/Crawling?
3. Transmigration?

Answer 21

1. Rolling: Selectin
2. Adhesion/crawling: ICAM-1 and integrins
3. Transmigration: PECAM-1 and integrins

Question 22

What is the primary site for complement production?

Answer 22

The liver

Question 24

Pure Red Cell Aplasia

1. What is it?
2. What dz’s is it associated with?

Answer 24

1. Rare form of marrow failure that is characterized by severe hypoplasia of marrow erythroid elements in the setting of normal granulopoiesis and thrombopoiesis
2. Assc. with Thymoma, lymphocytic leukemias and Parvovirus B19

Question 25

What are the key associations with Multiple Myeloma? (7)

Answer 25

**CRAB** (hyperCalcemia, Renal involvement, Anemia, Bone lytic lesions/Back Pain) + Primary amyloidosis, Rouleaux formation, and numerous plasma cells w/in bone marrow sample

Question 26

What is the marker for hematopoietic stem cells?

Answer 26

CD34+

Question 27

Chloramphenicol AE

Answer 27

This antibiotic can lead to both dose-dependent (reversible) **cytopenias** and dose-independent (irreversible) **aplastic anemia**.

Question 28

Which components of the skin drain to the _superficial inguinal lymph nodes_?

Answer 28

**_All skin_** from the umbilicus down, including the anus (below the pectinate line), **excluding** the testes, glans penis, and posterior calf

Question 29

Potential complications from hereditary spherocytosis (2)

Answer 29

1. Pigmented gallstones 2. Aplastic crises from parvovirus B19 infection

Question 30

Name the pentad for _Thrombotic thrombocytopenic purpura_

Answer 30

1. Neurologic symptoms 2. Renal failure 3. Fever 4. Thrombocytopenia 5. Microangiopathic hemolytic anemia