RBC Disorders- chapter 14 Flashcards
what does G6PD deficiency have protective role against
falciparum malaria
what measurements are used as surrogates for RBC mass
Hb, Hct, RBC count
what is the screening test for PNH
sucrose test
what is beta thalasemmia due to
gene mutations
what is the disorder described as inherited defect of RBC cytoskeleton- membrane tethering proteins
hereditary sclerocytosis
what is the definition of anemia
decrease in circulating RBC mass
describe the blood smear with normocytic anemia
larger cells with blush cytoplasm (due to residual RNA in cell)
What antibodies are involved in cold hemolysis type of immunohemolytic anemia
IgG
what is the characteristic of the RBCs in hemoglobin C
HbC crystals
what is acute chest syndrome a complication of
sickle cell anemia
what causes sickle cell anemia
AR mutation in beta chain of hemoglobin
what does G6PD deficiency render cells susceptible to
oxidative stress
who is trans 2 gene deletion alpha thalasemmia most common in
africa
What type of anemia is a primary marrow disorder in which only erythroid progenitors are suppressed
Pure red cell aplasia
what is the most common cause of death in adults with sickle cell anemia
acute chest syndrome
what is seen on electrophoresis with 4 gene deletion alpha thalasemmia
Hb barts (gamma chains formed into tetramers)
what are the lab findings with folate deficiency
macrocytic RBCs and hyperhsegmented neutrophils; glossitis; decreased serum folate and increased homocysteine
What is defined as ratio of packed RBC to total blood volume
Hematocrit
What antibodies are involved in cold agglutinin type of immunohemolytic anemia
IgM
What usually triggers the aplastic crises sometimes seen with hereditary spherocytosis
Acute parvovirus infection
when does the intravascular hemolysis with PNH mostly occur
often at night
where is folate absorbed
jejunum
describe the blood smear with beta thalasemmia major
microcytic, hypo chromic target cells and nucleated RBCs
what is the most common cause of vitamin B 12 deficiency
pernicious anemia
what is seen on electrophoresis in 3 deletion alpha thalasemmia
HbH
describe the levels of homocysteine and methylmalonic acid in vitamin B12 deficiency
increased
Describe the PTT and PT of hemophilia A
Prolonged PTT normal PT
what test is used for diagnosis of hereditary sclerocytosis
osmotic fragility test (increased fragility in hypotonic solution)
what does parvovirus B19 infection
progenitor red cells
describe the level of methylmalonic acid in folate deficiency
normal
Who is hemoglobin H disease more common in
Asian populations
What mutation is responsible for paroxsymal nocturnal hemoglobinuria
PIGA
what is 4 gene deletion called in utero
hydrops fetalis
What disorder is associated pencil cells (elongated Red cells
Iron deficiency
what is macrocytic anemia most commonly due to
folate or vitamin B12 deficiency
what screen is used to test for any HbS cells
metabisulfite screen
what occurs with 3 gene deletion in alpha thalasemmia
severe anemia beta chains form tetramers that damage RBCs
what does indirect coombs test confirm presence of
Abs in its serum
what is the change made in hemoglobin C
normal glutamic acid is replaced by lysine
what does G6PD present as
hemoglobinuria and back pain
What typically causes HUS
E. coli O157:H7
what appears on the blood smear with beta thalasemmia minor
target cells and microcytic hypo chromic RBCs
Describe the marrow aspirated of aplastic anemias
Often yield little material; dry tap
what is absent with PNH
GPI
What disorder has heinz bodies and bite cells
G6PD deficiency
When are the signs of fetal distress with hydrophobic details evident
3rd trimester
Where is transferrin synthesized
Liver
what type of hemolysis goes with sickle cell anemia
both intra and extra
what test is used to confirm immune hemolytic anemia
direct coombs test
what chromosomes are the 2 beta genes located on
11
What disorder is defined as inherited deficiency of platelet membrane glycoprotein complex (receptor for vWF)
Bernard-Soulier syndrome
Describe the change in MCHC for hereditary spherocytosis
Increased MCHC due to dehydration because of loss of K+ and H2O
What is the most common complication of transfusions
Febrile nonhemolytic reaction
what emerge on blood smear of hereditary sclerocytosis
howell-jolly bodies
What GPI-linked protein issues are associated with paroxysmal nocturnal hemoglobinuria
CD55, CD59, C8 binding protein
describe the MCV in microcytic, normocytic and microcytic anemia
micro= less than 80; normo= 80-100; macro= greater than 100
what is the disorder classified as decreased synthesis of global chains of hemoglobin
thalassemia
what is normocytic anemia due to
increased peripheral destruction or underproduction
What type of anemia is a rare autosomal recessive disorder caused by defects in multiprotein complex that is required for DNA replace that leads to aplastic anemia
Franconi anemia
what is alpha thalasemmia usually due to
gene deletion
what does direct coombs test confirm presence of
presence of Ab-coated RBCs
What are the clinical presentations of sequestration crises of sickle cell disease
Rapid splenic enlargement, hypovolemia, sometimes shock
what disorder should you think of with crew cut appearance on x-ray and chipmunk-like face of skull
massive erythroid hyperplasia in beta thalasemmia major
how do you treat hereditary sclerocytosis
splenectomy
What enzyme is associated with TTP
ADAMTS13 deficiency plasma enzyme
What chromosome are the alpha-globin genes on
16
what is damaged with aplastic anemia
HSC
What antibodies are involved in warm antibody type of immunohemolytic anemia
IgG
Describe the blood smear of beta thalassemia major
Anisocytosis, poikilocytosis, microcytosis, hypochromia
what are carriers of thalassemia often protected against
plasmodium falciparum malaria
what can confirm presence and amount of HbS
Hb electrophoresis
Where is hepcidin synthesized
Liver
what is the chain with sickle cell anemia
normal glutamic acid (hydrophilic) replaced by valine (hydrophobic)
How is paroxsymal nocturnal hemoglobinuria diagnosed
Flow cytometry
What is the Pentad associated with TTP
Fever, thrombocytopenia, microangiopathic hemolytic anemia, transient neurologic deficits, renal failure
what appears on the blood smear for sickle cell anemia
howell-jolly bodies
what is the hallmark of microangiopathic hemolytic anemia
schistocytes (look like helmet)
What is the most specific morphological finding with hereditary spherocytosis
Spherocytosis (smears that have small, hyperchromic red cells lacking the central zone of parlow)
Who does sequestration crises occur in
Children with sickle cell disease that have intact spleens
what is the main cause of death in PNH
thrombosis
what are the clinical lab findings with extravascular hemolysis (in general)
hemoglo binemia, hemoglobinuria, hemosiderinuria, decreased serum haptoglobin
what is the presentation when 2 genes are deleted in alpha thalasemmia
mild anemia with slightly increased RBC count
What is the most common nutritional disorder in the world
Iron deficiency anemia
What is another name for alpha thalassemia with deletion of 3 genes
Hemoglobin H disease
What are the clinical presentations of von willebrand disease
Epistaxis, excessive bleeding from wounds, menorrhagia
what is shown in the biopsy of aplastic anemia
empty, fatty marrow
Describe the level of activity of hepcidin with hemochromatosis
Inappropriately low
What do the RBCs lack in beta thalassemia major
HbA
what does the oxidative stress with G6PD precipitate Hb as
heinz bodies
