RBC and Bleeding Disorders IV Flashcards
PIGA mutation
in paroxysmal nocturnal hemoglobinuria
phosphatidylinositol glycan complementation group A gene
x-linked
paroxysmal nocturnal hemoglobinuria
mutation in PIGA
-rare
only hemolytic anemia caused by acquired genetic defect**
RBCs deficient in three GPI-linked proteins that regulate complement activity
-susceptible to lysis - intravascular hemolysis (MAC complex)
PNH at night
because blood pH slight decrease - increased activity of complement
death in PNH
venous thrombosis
-of hepatic, portal, or cerebral veins
progression of PNH
may go to AML or MDS
diagnosis of PNH
flow cytometry
-detects RBCs deficienct in CD59 and CD55
CD59
deficient in PNH
-detected with flow cytometry
tx of PNH
monoclonal antibody
- eculizumab
- inhibits conversion of C5
immunohemolytic anemias
Abs bind RBCs leading to premature destruction
aka autoimmune hemolytic anemias
warm Ab type
IgG antibodies active at 37C
primary
secondary, SLE, drugs, neoplasms
cold agglutinin type
IgM antibodies active below 37C
acute - mycoplasm infection, mono
chronic - idiopathic, neoplasms
cold hemolysin type
IgG antibodies active below 37C
rare - children with viral infections
children with viral infections
cold hemolysin type
mycoplasm and mono infection
cold agglutinin type
PCN and cephalosporin
drug induced warm-antibody type
alpha-methyldopa
telomerase breaking drug
lead to warm -AB type
paroxysmal cold hemoglobinuria
cold hemolysin type
IgG bunds P blood group antigens
mycoplasma pneumonia
cold agglutinin type of immunohemolytic anemias
IgM Abs bind RBC at low temperatures
direct coombs antiglobulin test
patient RBCs mixed with sera with Abs for Ig/complement
clumping
indirect coombs antiglobulin test
patients serum tested for ability to agglutinate commercial RBCs
test used to characterize antigen target and temperature dependence of responsible antibody
quantitative test**
to characterize antigen target and temperature dependence of responsible antibody
indirect coombs test
cardiac valve prosthesis
hemolytic anemia from RBC trauma
microangiopathic hemolytic anemia
seen with DIC, TTP, HUS, malignant HTN, and SLE, and disseminated cancers
microvascular lesion - luminal narrowing
deposition of fibrin and platelets
shear stress
schistocytes, burr cells, helmet cells, triangle cells
in PBS with traumatic hemolytic anemia
