Hemolytic anemia 2 Flashcards
thalassemia
genetic decreased synthesis of alpha or beta global chains
alpha genes
chromosome 16
4 genes
beta genes
chromosome 11
2 genes
secondary hemochromatosis
iron accumulation
immunohemolytic anemia
RBC coated with antibodies or complement and removed by spleen
types of immunohemolytic anemia
warm antibody type
cold agglutinin type
cold hemolysis type
warm antibody type immunohemolytic anemia
IgG 37C
microspherocytes
antibody specific for Rh antigens
diagnosed via Direct Coombs test
cold agglutinin type immunohemolytic anemia
IgM
acute cold agglutinin type
mycoplasma mononucleosis (EBV) CMV influenza HIV
chronic cold agglutinin type
idiopathic
lymphoma
cold hemolysis type immunohemolytic anemia
IgG
beta thalassemia
decreased synthesis of beta global chain
mutations associated with beta thalassemia
beta0- no chains due to chain termination mutations
beta+- reduced number of chains due to splicing or promoter region mutations
Major thalassemia
Cooley’s anemia
2 thalassemia alleles
pathogenesis of major beta thalassemia
reduced beta synthesis with excessive alpha production
insoluble alpha aggregates form causing ineffective erythropoiesis– most cells die
abnormal cells that get out cause extravascular hemolysis which leads to anemia and tissue hypoxia
marrow expands to compensate which leads to skeletal deformities
diagnostic findings for beta thallasemia
increased RBC# decreased MCV, MCH, MCHC normal RDW hypo chromic microcytic target cells increased HbA2
complications of beta thalassemia major
skeletal abnormalities–new bone formation in the outer table –> perpendicular skull radiations
treatment of beta thalassemia major
marrow transplant
minor thalassemia
heterozygous thalassemia alleles
alpha thalassemia
alpha global gene deletions
severity depends on number of genes affected
1 mutation alpha thalaseemia
silent carrier- normal
2 mutation alpha thalassemia
trait
microcytosis
hypochromia
mild anemia
3 mutation alpha thalassemia
HbH disease
excess beta microcytic hypo chromic hemolytic anemia
mild jaundice
moderate hepatosplenomegaly
4 mutation alpha thalassemia
Hb Bart Hydrops Fettles syndrome excess gamma with high O2 affinity severe anemia ascities/edema hepatosplenomegaly skeletal and CV malformations die in utero
paroxysmal nocturnal hemoglobinuria
rare acquired stem cell disease with somatic mutations affecting RBC membrane
PIG-A defect for RBC anchor GPI
consequences of PNH
sensitive to complement mediated lysis
proteins cannot attach to cell
periodic episodes of night time bloody urine
diagnostic test for PNH
acidified serum test
sucrose hemolysis test
flow cytometry
treatment for PNH
marrow transplant
growth factors
anti-complement antibody to reduce hemolysis
acidified serum test
for PNH
acidified serum activates the alternative complement pathway which causes lysis
sucrose hemolysis test
for PNH
sucrose promotes complement binding which leads to lysis
flow cytometry
for PNH looks at cell types that could be missing GPI granulocytes monocytes lymphocytes RBC missing CD55 and CD59
microangiopathic hemolytic anemia (MAHA)
damage to red cells via contact with dense fibrin strands
causes of MAHA
DIC thrombotic thrombocytopenia purport hemolytic uremia syndrome SLE malignant HTN
diagnostic features of MAHA
schistocytes
treatment for warm antibody hemolytic anemia
corticosteroids
splectomy, rituximab
drug related hemolytic anemia- happen/drug adsorption
drug binds to RBC and IgG formed against it
drug related hemolytic anemia- immune complex
IgM forms after exposure to drug
further exposure leads to drug and antibody adsorbing to RBC
drug related hemolytic anemia- autoantibody formation
IgG forms to drug, possible Rh specificity
Direct Coombs test
distinguishes immune from non immune hemolytic anemias
antibody on cells agglutinate when exposed to antihuman antibody
diagnostic markers of cold agglutinin syndrome
red cell agglutinates
rouleaux
paroxysmal cold hemoglobinuria
intravascular hemolysis when exposed to cold due to IgG agasint P antigen
antibody and early complement bind at low temperatures and then terminal complement binds with warming which causes lysis
PCH associated with
ssyphillis
viral infection in kids
diagnostic testing of PCH
Donath-Landsteiner test
Donati-Landsteiner test
for PCH
RBC and complement mixed at low temps–bind
warm –> intravascular hemolysis
