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Flashcards in Hematology/oncology Deck (109)
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1

PT= prothrombin time

Measures extrinsic coagulation

Increased in:
- deficiency of Factors I (fibrinogen), II (thrombin), V, VII, X
- Liver dysfunction--> Factor VII depleted first--> PT increased first
- Warfarin therapy

2

PTT= Partial Thromboplastin Time

Measures intrinsic, common coagulation

Contains Factor VII--> time increased with deficiency of any other factor
- Increased time in Heparin therapy
- Increased time d/t APLS (antiphospholipid antibody syndrome), sepsis, hemophilia

3

TT= Thrombin time

Conversion of fibrinogen--> fibrin
- Prolonged by heparin

4

Ceruloplasmin

Carries Copper (decreased in Wilson's disease)
- alpha-2-globulin produced by liver, kidneys

5

Anaplasia

Loss of cell polarity, architecture
- variation in size, shape (pleomorphic)
- Giant multinucleated cells
- Nuclear hyperchromatism, pleomorphism
- Increased nuclear:cytoplasm ratio, abnL mitoses

6

Platelet

Life span: 8-10 days
Dense granules= ADP, calcium
Alpha granules= vWF, fibrinogen
- vWF receptor= GpIb; carries/protects factor VIII
- Fibrinogen receptor= GpIIb/IIIa

7

Blood cell differential

Neutrophils (55%)
Lymphocytes (30%)
Monoctes (5%)
Eosinophils (3%)
Basophils (0-1%)

8

Neutrophils

Increased in bacterial infection
- Phagocytic
- Multilobed nucleus

Small granules:
- Alkaline phosphatase
- Collagenase
- Lysozyme
- Lactoferrin

Larger granules: lysosomes:
- Acid phosphatase
- Peroxidase
- Beta-glucuronidase

Hypersegmented polys (5+ lobes) seen in B12/folate deficiency (enlarged nuclei)
* Increased band cells in myeloid proliferation states

9

Macrophages

Precursor= monocyte (kidney-shaped nucleus)

Activated by IFN-gamma
Presents MHC II
Cell marker= CD14

Secretes TNF-alpha

10

Eosinophil

Protects against helminths (INVASIVE)
- Seen in neoplasia, asthma, allergic processes, collagen vascular diseases, invasive parasites
Contains major basic protein

Bilobate nucleus
Phagocytic for antigen-antibody complexes

Produces:
- Histaminase
- Arylsulfatase
** limits reaction after mast cell degranulation

11

Basophil

Mediates allergic reaction
Contain:
- Heparin
- histamine (vasodilator)
- Leukotrienes (LTD4)

12

B lymphocyte

Stem cell in bone marrow (matures in marrow)
Migrates to:
- Follicles of lymph nodes
- White pulp of spleen
- Unencapsulated lymphoid tissue

MHC II APC

13

O-negative mothers

Anti-A and Anti-B antibodies produced are IgG (vs other blood types that produce IgM)
- BUT, Hemolytic disease of newborn only occurs in ~3% of O- moms

Rh= IgG antibodies, can cross placenta for all maternal types
- Administer Rho(D) Ig (RhIg) at first delivery to prevent sensitization
--> Erythroblastosis fetalis seen in subsequent babies of untreated mothers

14

Factor V Leiden mutation

Factor V resistant to inhibition by APC (activated protein C)
- most common cause of inherited hypercoagulability in whites

15

ESR

Erythrocyte sedimentation rate

Increased in: infections, autoimmune diseases, malignant neoplasia, GI disease, pregnancy (inflammation)

Decreased in:
- Polycythemia
- Sickle cell anemia
- CHF
- Microcytosis
- Hypofibrinogenemia

16

Acanthocyte

Spur cell

Seen in:
- Liver disease
- abetalipoproteinemia (cholesterol dysregulation states)

17

Basophilic stippling

Ribosomal RNA remnants in RBC

Seen in:
- Thalassemia
- Anemia of chronic disease
- Lead poisoning

18

Heinz bodies

Oxidation of hemoglobin sulfhydryl groups--> denatured hemoglobin precipitation--> damage to RBC membrane--> formation of bite cells (macrophages remove precipitated hemoglobin, part of membrane

Stains with crystal violet stain

Seen in G6PD deficiency, alpha thalassemia

19

Howell-Jolly bodies

Basophilic nuclear remnants in RBCs
- Normally removed by splenic macrophages

Seen in patients with asplenia, hyposplenia (sickle cell children)
Or, after napthalene (mothball) ingestion

20

TIBC

Total iron binding capacity= Transferrin (transport of iron in blood)
- increased when body needs more iron
- increased by OCPs, pregnancy

21

Ferritin

Storage form of iron (in macrophages in bone, liver)

22

Haptoglobin

Picks up hemoglobin after intravascular hemolysis--> brings to macrophages ("suicide protein")
- alpha-2-globulin produced by liver, kidneys

23

Alpha thalassemia

Defective alpha-globin
- cis form in Asians
- trans form in Africans

4 gene deletion= Hb Barts (hydrops fetalis)--> dead in utero

3 gene deletion= HbH disease
- Excess Beta-globin that can't bind alpha forms B4 (HbH)

1-2 gene deletion: no clinically significant anemia

24

Beta-thalassemia

Seen in Mediterranean populations

mRNA processing problem leading to underproduction/absent beta-chain

Minor/Intermedia (heterozygote):
- Beta chain under-produced (asymptomatic)
- Confirmed by increased HbA2 (> 3.5% on electrophoresis)

Major: (homozygote)
- Absent beta chain--> anemia (blood transfusion)--> secondary hemochromatosis
- Marrow expansion--> crew cut skull, skeletal deformities, chipmunk face
- Increased HbF (alpha2gamma2)

**HbS/Beta-thal heterozygote--> mild/moderate sickle cell disease (depends on beta production)

25

Lead poisoning

Inhibits:
1. ferrochelatase--> protoporphyrin excess
2. ALA dehyratase--> delta-ALA excess
3. rRNA degradation--> basophilic stippling

Symptoms:
- Lead lines on gingiva (Burton's lines), metaphysis of long bones)
- Encephalopathy, Erythrocyte basophilic stippling
- Abdominal colic, sideroblastic Anemia
- Wrist, foot drop
- Adults: H/A, memory loss, demyelination
- Children (lead paint): mental deterioration

Tx: Dimercaprol, EDTA (1st line)
- Succimer in pediatric overdose (chelator)

26

Sideroblastic anemia

X-linked defect in delta-ALA synthase
---> Defective heme synthesis
- Glycine, succinyl coA not converted to delta-aminolevulinic acid
** Can also be caused by alcohol, lead, isoniazid, myelodysplastic syndrome

Ringed siderblast with iron-laden mitochondria (have iron, can't make heme!)

Tx: pyridoxine (B6= cofactor for delta ALA-synthase)

27

Folate deficiency

Hypersegmented neutrophils
Megaloblastic anemia
- Increased Homocyteine

Symptoms:
- Sore tongue
- Pain on swallowing
- Angular stomatitis
- GI upset
- Hyperpigmentation

28

B12 deficiency

Increased homocysteine, increased methylmalonic acid (MMA)

Symptoms:
- Neurologic: subacute combined degeneration (involvement of B12 in fatty acid pathways, myelin synthesis
- Peripheral neuropathy with sensorimotor dysfunction
- Posterior column (vibration/proprioception)
- Lateral corticospinal (spasticity)
- Dementia

**Pernicious anemia: older N. European woman; lemon-yellow coloring, shiny smooth tongue (atrophic glossitis), shuffling broad-based gait

29

Plummer-Vinson syndrome

Triad:
- iron deficiency anemia
- Esophageal webs
- Atrophic glossitis

30

Hepcidin

Protein released by liver in response to inflammatory state
- Binds ferroportin on intestinal mucosal cells, macrophages--> inhibits iron transport, release of iron from macrophages
--> anemia of chronic disease

** Body stopping iron release in state of inflammation since bacteria feed off iron to grow