Hematology/Coagulation Flashcards
Antigen negative % frequencies for Rh (D+) antigens
C = 20
E = 68
c = 23
e = 3
Antigen negative % frequencies for Rh (D-) antigens
C = 97
E = 99
c = 2
e = <1
Antigen negative % frequencies for CAUCASIAN antigens
Fya 32
Fyb 20
Jka 24
Jkb 26
M 21
N 30
S 48
s 10
Antigen negative % frequencies for AFRICAN descent antigens
Fya 20** verify
Fyb 77
Jka 8
Jkb 52
M 26
N 25
S 68
s 6
3 components of hemoglobin molecule
- Iron
- Globin protein chains
- Protoporphyrin
90% of tissue iron (Fe3+) is STORED in these 2 forms
- Ferritin (serum, tissue)
- Hemosiderin (marrow, other tissue sites)
Globin proteins that transports iron (in serum)
Transferrin
Hemoglobin components
- 2 alpha + 2 beta (HgbA) or 2 gamma (Hgb F) globin protein chains
- 4 heme groups w/protoporphyrin ring and ferrous iron
- 4 oxygen molecules
Most common cause of hypochromic anemia (and microcytic)
Iron deficiency
Heme synthesis disorders present with these cells
Sideroblasts (sideroblastic anemia)
Disorders of Globin protein chain synthesis
A-thalassemia
B-thalassemia
Alpha or beta chain production disorder - causes excess of complimentary chain
Major integral protein of rbc membrane - 20%
Glycophorin
Most abundant peripheral protein of rbc membrane cytoskeleton
Spectrin (25-30%) of total membrane; 75% of peripheral protein
RBC membrane is permeable to 2 cations
Na+ and K+
25% of rbc membrane is comprised of this lipid
Cholesterol
What percentage of total body iron is bound to heme
66% (2/3)
Other (1/3) 33% stored in bone marrow
Normal adult hemoglobin contains these types and percentages of hemoglobin
Hgb A = 95-97%
Hgb A2 = 2-3%
Hgb F = 1-2%
O2 dissociation LEFT shift
Decreased O2 delivery to tissues
O2 dissociation RIGHT shift
Increased oxygen delivery to tissue
3 types of abnormal hemoglobin (unable to transport oxygen
Carboxyhemoglobin
Methemoglobin
Sulfhemoglobin
Senescence/removal of red cells by these 2 pathways and percentages
- Extravascular - 90% (RES)
- Intravascular - 5-10% (blood vessels)
Emblem- Meyerhof glycolytic pathway
Provides 90% of ATP needed for rbc survival
Components of red cell cytoskeleton
-Spectrin. (GP-A)
-ankyrin (GP-C)
-protein 4.1
-actin (GP-B)
-adducin
Cholesterol accumulation in rbc membrane (liver disease) results in this rbc morphology
Target cells
Normal P50 value (Oxygen saturation)
26-30 mmHg
Intravascular hemolysis process steps (5-10% red cell removal)
-rbc breakdown in blood vessel
-rbc rupture releases hemoglobin
- Haptoglobin binds free hemoglobin
-hTG/HGB carried to liver
- excess HGB is excreted in urine (hemoglobinuria) or found in plasma as unbound dimers (hemoglobinemia)
Extravascular hemolysis process steps (90% red cell removal)
-RES (spleen) phagocytize red cells
-iron+transferrin back to bone marrow
-Globin returns to amino acid pool
-biliverdin+albumin back to liver as bilirubin
-bilirubin-glucorondide converted to urobilinogen, excreted to intestines with bile
-protoporphyrn ring disassembled, alpha carbon exhaled as CO (carbon monoxide)
Tests used to measure hemolysis
Extravascular - direct/indirect bilirubin
Intravascular- haptoglobin (will see hemoglobinemia and hemiglobinuria when haptoglobin is exhausted)
Causes of anemia (decreased rbc count, low h/h
-nutritional deficiencies
-blood loss
-increased rbc destruction
-decreased production of rbcs
-heredity/acquired defects
Reference method for measuring hemoglobin
Cyanmethemoglobin
Hematocrit (packed cell volume)
Determined by centrifugation
= MCV * rbc count
Normal: 47 (m); 42 (f) +/- 5%
MCV - estimation of average rbc size
Hct *10 / rbc count
Normal: 80-100fL
MCH - measuring hemoglobin content
Hgb *10 / rbc count
Normal: 27-31 pg
MCHC - corpuscular hemoglobin concentration
Hgb *100 / HCt
Normal: 32-36%
Indices:
MCV(fL)/MCHC(%)
- Normocytic (80-100)
- normochromic (32-36)
Bone marrow failure, hemolytic anemia, renal disease, leukemia, malignancy
MCV(fL)/MCHC(%)
- Macrocytic (>100)
- normochromic (32-36)
Non/Megaloblastic macrocytic anemias (liver disease, myelodysplasias)
Conditions associated with
MCV(fL)/MCHC(%)
- MICROcytic (<80)
- Hypochromic (<32)
- Iron deficiency
- sideroblastic anemia
- thalassemia
- lead poisoning
RDW - red cell distribution width
Size variation in rbc population
Normal: 11.5 - 14.5%
Complement:
2 forms of C3 convertase (C3b bound to pathogen surface=opsonization)
- C4b2a (classical)
- C3bBb (alternative)
Anaphylatoxins:
C3a, C4a, C5a
Chemotoxins:
C3a, C5a
recruit phagocytes
-recruit phagocytes
-induce contraction of smooth muscle cells
-increase vascular permeability
Function of T cells with CD 4
Activate B cells, T cells and macrophages
Function of T cells with CD 8
Destroy foreign cells or body cells with foreign agents
Vitamin K dependent clotting factors (Prothrombin group)
Factor 2, 7, 9, 10 protein C, protein S
INR = patient PT / mean PT ^isi
Coagulation proteins formed in this organ
Liver
Common pathway - coagulation factors
Factor: 10, 5, 2, 1
Extrinsic pathway factors
Factor: 7, tissue factor (3)
Intrinsic pathway factors
Factor: 12, 11, 9, 8
PT - time to clot via Extrinsic pathway
Normal: 11-14 sec
Factor 7, tissue favor + Common pathway (10, 5, 2, 1)
aPTT - time to clot via INTRINSIC
Measures activation and contact: factors 12, 11; common pathway; 9, 8
Platelet syndrome: adhesion defect, lack of IX-V, giant platelets
Bernard-Soulier syndrome
Platelet function disorder: gingival bleeding, epitaxis, decreased adhesion and aggregation
Glanzmann’s thrombathemia
Platelet impaired signaling with small platelets
Wiscott-Aldrich syndrome