Hematology Flashcards
What is the receptor on platelets that binds to vWF?
GP Ib
What is the receptor on platelets that binds other platelets and fibrinogen?
GP IIa/IIIb
What are the five major causes of eosinophilia?
Neoplasms Asthma Allergic processes CT diseases Parasites (NAACP)
What are the histological features of neutrophils?
Multilobed nuclei
Hypersegmented nuetrophils are seen in what condition?
b12 deficiency (pernicious anemia)
What is the function of basophils?
Cells that contain heparin and histamine (similar to mast cells)
What is the cause of hemophilia A?
Factor 8 deficiency
What is the cause of hemophilia B?
Factor 9 deficiency
What are the factors that warfarin inhibits?
10 9 7 2 protein S and C
What is the function of protein S and C?
C is activated by thrombomodulin/thrombin complex, which in turn activates protein S, and deactivates factors 8 and 5
What is the order of the extrinsic pathway?
3
7
10 (+8)
What is the order of the intrinsic pathway?
12
11
9
10
What are the factors that comprise the tenase complex? What does this complex do?
8 and 9
Increases thrombin activation
What is the MOA of tPA?
activates plasminogen to plasmin
What is the MOA of clopidogrel?
Prevents ADP receptor binding
What is the MOA of abciximab?
Ab against GP IIa/IIIb
What is the MOA of ASA’s antiplatelet effect?
inhibits thromboxane A2 synthesis
What is von willebrand disease?
Insufficient vWF
Basophilic stippling of RBCs is found in what diseases? (4)
anemia of chronic disease
alcohol abuse
Pb poisoning
thalassemias
Bite cells = what disease?
G6PD deficiency
elliptocytes = what disease?
Hereditary elliptocytosis
Ringed siderblasts = what disease?
Sideroblastic anemia (microcytic anemia
What are the five major causes of microcytic anemia?
Fe deficiency Thalassemias sideroblastic anemia Anemia of chronic disease Pb poisoning
Heinz bodies = what disease? What are they?
G6PD deficiency
Denatured Hb
Howell-Jolly bodies = what disease?
hyposplenia or asplenia
What are schistocytes? What are these seen in?
Broken RBCs—DIC, TTP/HUS mechanical heart valves
What are the two major causes of macrocytic anemia?
B12 deficiency
Folate deficiency
What is/are the labs that separate B12 deficiency and folate deficiency?
Methylmalonic acid will be high in B12 deficiency
What is the one reaction in the body that requires THF?
Conversion of homocysteine to methionine
What is TIBC?
The amount of Fe that can be stored on transferrin (the number of open spots, thus higher numbers = lower serum ferritin)
What are the two storage forms of Fe?
Ferritin (dynamic)
Hemosiderin (lost)
What is plummer vinson syndrome?
Fe deficiency
Esophageal webs
atrophic glossitis
What is the Hb formed when there is are three (or four total) deletions of the alpha globin gene?
HbH (beta4 tetramer)
What is Bart’s hb? What disease is it found in?
gamma4 tetramer of Hb, found in 4 alpha gene deletions
What is beta thalassemia minor?
underproduction of beta globin. This is usually asymptomatic, since there is an upregulation of HbA2 (alpha2, delta2)
What are the components of HbA?
alpha2beta2
What are the components of HbA2?
alpha2delta2
What are the components of HbF?
Alpha2gamma2
Mohawk appearance of a skull x-ray = what disease? Why?
beta thalassemia major d/t increased hematopoiesis in the skull bones
What virus are people with beta thalassemia major particularly susceptible to?
Parvovirus B19 d/t infection of erythroid progenitor cells
What are teardrop cells seen in?
Primary myelofibrosis
What are Target cells seen in? (HALT)
HbC disease
Asplenia
Liver dz
Thalassemia
What are iron studies like with Fe deficiency anemia? (Fe, TIBC, ferritin)
Low Fe
High TIBC
Low Ferritin
What is the major toxicity of Pb poisoning?
Inhibition of ferrochelatase and ALA dehydratase
What are the ssx of Pb poisoning?
Lead lines in gingiva
Encephalopathy
What is the treatment for Pb poisoning?
EDTA or Succimer drops
What are the PBS findings for Pb poisoning?
Microcytic anemia with basophilic stippling
What is the hereditary cause of sideroblastic anemia? What is the inheritance pattern of this?
X-linked deficiency/defect i delta-ALA synthase gene
What drug classically causes sideroblastic anemia? How? What is the treatment for this?
Isoniazid d/t inhibition of ALA synthase
B6 supplementation
What are the PBS findings of sideroblastic anemia?
Ringed sideroblasts d/t Fe laden mitochondria
What are the iron studies like with sideroblastic anemia? (Fe, TIBC, Ferritin)?
Increase Fe
Normal TIBC
Increased Ferritin
What are homocysteine and methylmalonic acids levels like with folate and B12 deficiencies respectively?
B12 = both high Folate = only Homocysteine levels are elevated
What is orotic aciduria, and what causes it? How does this present?
Inability to convert orotic acid to UMP because of a effect in UMP synthase
Presents in childhood as megaloblastic anemia that cannot be corrected with folate or B12
How do you differentiate orotic aciduria from ornithine transcarbamylase deficiency?
No hyperammonemia with orotic aciduria
What is non-megaloblastic macrocytic anemia?
Macrocytic anemia in which DNA synthesis is not impaired. Usually caused by EtOH-ism or cirrhosis
What are the two different types of normocytic, normochromic anemias?
Hemolytic vs nonhemolytic
What are the following labs like with intravascular hemolysis:
- Haptoglobin
- LDH
- reticulocytes
Decreased haptoglobin (is bound)
Increased LDH
-Increased reticulocytes
What happens to LDH and unconjugated bili levels in extravascular hemolysis?
Increased LDH and increased bili
What is the role of hepcidin?
binds ferroportin in the intestinal mucosa and macrophages, thus inhibiting Fe uptake
What is the pathophysiology of anemia of chronic disease?
Chronic inflammation leads to increased hepcidin release, and an increase in ferritin levels, as Fe is preferentially stored away from bacteria
What are the following labs like with anemia of chronic disease:
- Fe
- TIBC
- Ferritin
Low Fe
Low TIBC
High Ferritin
What is the body’s main form of Fe storage?
Ferritin
How does CKD lead to anemia?
Low EPO = low hematopoiesis
What is aplastic anemia, and what are the classical findings of it?
Pancytopenia, characterized by normal cell morphology, but hypocellular bond marrow with fatty infiltration
What is the bone aspiration finding of aplastic anemia?
Dry tap (fat cells)
What is the treatment for aplastic anemia?
Marrow transplant
g-CSF
What viruses can cause aplastic anemia? (4)
Parvo B19
HIV
HCV
EBV
What is the pathophysiology of Fanconi anemia?
DNA repair defect, leading to aplastic anemia