Pathology Flashcards
Where is vWF stored?
W-P bodies of endothelium
What is stored in W-P bodies?
1) vWF
2) p-selectins
What does vWF bind?
SEC and platelets
What receptor doe platelets use to connect to fibrinogen?
GpIIb/IIIa
Petechiae occurs with (quantitative/qualitative) platelet disorders
quantitative (thrombocytopenia)
Autoimmune production of IgG against platelet antigens is called ____
ITP
In ITP, autoimmune antibodies are made in the _____. Red cells are consumed in the _______
Antibodies made in spleen
Red cells consumed in the spleen
Dx: Child with ITP
Rx: ________
usually self-limiting, possible platelet transfusion
Dx: Adult with chronic ITP, low platelet crisis
Rx: ______
IVIG
Dx: Adult with chronic ITP, low platelet crisis
Surgical option?
Splenectomy
Pathologic platelet micro-thrombi in small vessels is called _____
Microangiopathic Hemolytic Anemia
TTP is caused by a deficient enzyme _____
ADAMTS13
ADAMTS13 normally cleaves _____ multimers into monomers
vWF
The lack of ADAMTS13 in TTP is usually due to an underlying ________
autoimmune Dz
Hemolytic Uremic Syndorme primarily affects the _______ (organ)
kidney
The usual causative agent for HUS is ______
E. coli O157:H7
E. coli O157:H7 has the virulence factor ______ that damages renal endothelial cells
verotoxin
Name 2 Microangiopathic Hemolytic Anemias:
- TTP (thrombotic thrombocytopenic purpura)
2. HUS (Hemolytic Uremic Syndrome)
In Microangiopathic Hemolytic Anemias, bleed time (increases/decreases) and PT/PTT is ______
increases
PT/PTT is normal
How do you treat HUS and TTP?
- plasmapheresis
2. corticosteroids
In Bernard-Soulier, there is a genetic deficiency in ______
GP1b
In Bernard-Soulier, what function is impaired?
platelet adhesion
Platelets without GP1b can’t bind ____
vWF
Bernard-Soulier Syndrome
Blood smear of Bernard-Soulier Syndrome patient shows _______
enlarged platelets
In Glanzmann’s Thrombasthenia there is a genetic deficiency in ________
GIIb/IIIa
ASA blocks cyclooxygenase preventing platelets from making ____
TXA2
In vWF disease (PT/PTT) is increased
PTT
Which test is abnormal in vWF disease?
- ristocetin test
2. and PTT
What enzyme does coumadin block?
epoxide reductase
where is vitamin K generated?
gut bacteria
You can follow the extent of liver failure by measuring (PT/PTT)
PT
The best screening test for DIC is _______
elevated D dimer
A serine protease that converts plasminogen to plasmin
tPA
Dissolves fibrin clots:
1) cleaves fibrin
2) clears serum fibrinogen
3. destroys clot factors
plasmin
Lab findings: increased PT and PTT, increased bleed time, increased fibrinogen splits, no D-dimer
Dx: ?
overactive plasmin
Lines of Zahn: their presence implies thrombosis at a site of rapid blood flow that happened with the patient (alive/dead)
alive!
Coagulation can be kicked off by either ____ or ___
SEC or TF
Blocks platelet aggregation (TXA2/ PGI2)
PGI2 blocks
Promotes platelet aggregation (TXA2/ PGI2)
TXA2 promotes
on the surface of endothelial cells, serves as a cofactor for thrombin
TM: thrombomodulin
Name 3 endothelial damages that increase clot risk
- atherosclerosis
- vasculitis
- elevated homocystine
Vitamin k is required for which blood protein factors to work?
2, 7, 9, 10, C and S
Which has the shortest half-life? (2, 7, 9, 10, C or S)
C and S! hence the need for HEP therapy along with coumadin
Heparin binds and activates _____
ATIII
What are the 4 types of micorcytic anemias?
- sideroblastic
- thalasemia
- iron deficient
- anemia of chronic Dz
anemia, dysphagia w/ esophageal web, red beefy tounge is ____ _____ disease
plummer-vinson
what acute phase reactant sequesters Iron?
hepcidin
what does TIBC stand for?
total iron binding capacity
Hx: bone marrow suppression w chemo and anemia
how can you treat the anemia?
erythropoietin
Protoporphyrin is attached to iron in what cell compartment?
mitochondria
iron laden mitochondria occurs in _______ anemia
sideroblastic
alcoholism can lead to a ________ anemia
sideroblastic
intracellular protein that stores iron and releases it in a controlled fashion, commonl measured in labs
ferritin
decreased synthesis of globin chains is called ______
thalassemia
which leads to a worse thalasemia, cis or trans deletion?
cis
Where is the cis deletion thalassemia more commonly seen? (asia/africa)
asia
4 beta chains in a thalassemia is called Hb__
HbH
a tetramer of gamma chains in hemoglobin is called Hb_____
Hb barts
Beta thalassemia leads to (microcytic/macrocytic) anemia
microcytic
Massive erythroid hyperplasia such as in SS and beta thal leads to what appearance on skull radiograph?
“crew cut”
due to massive erythroid hyperplasia
why is a person w/ beta thalassemia at risk for hemochromotosis?
frequent transfusion
Electrophoresis: no HbA, increased HbA2 and HbF
Dx: ________
beta thalassemia major
Macrocytic anemia is usually due to a deficiency in ______ of _______
- folate
2. vitamin B12
Three diseases that can lead to a macrocytic anemia are:
- alcoholism
- liver disease
- chemo drugs: 5-FU, methotrexate and folate def.
R binder is produced by the ______, then complexed to vit. B12 for absorption
salivary glads
intrinsic factor that binds B12 is produced by the _____ cells o the stomach
parietal
B12 is stored in large volume in the _______ (organ)
liver
Pernicious anemia is due to _________ destroying the parietal cells of the stomach
autoimmune disease
With low serum B12, serum homocystine and _______ build up, leading to spinal cord damage
methylmalonic acid, can damage the spinal cord
Hemoglobinemia with hemoglobinuria and hemosiderinuria (intravascular/extravascular) destruction of RBCs
intravascular destruction
brown urine”, with chronic intravascular hemolysis is called _________
hemosiderinuria
what 3 tethering molecules are deficient in Hereditary spherocytosis?
- spectrin
- ankrin
- band 3.1
what virus infects erythrocyte pre-cursors?
Parvovirus B19
Treatment for Hereditary spherocytosis is _______
splenectomy
Howell-Jolly bodies indicate _______
splenic dysfunction, (such as post splenectomy)
Three risk factors for RBC sickling are:
- acidosis
- dehydration
- hypoxemia
Swollen hands and feet due to vaso-occlusive infarts of bones is called _______
dactylitis
in kids with SS, there is increased risk of infection with _____ _____
encapsulated bacteria
What lab test can allow identification of HbS?
Metabisulfite