Heme/Onco II Flashcards
thalassemia
microcytic anemia
a-thalassemia
defect a-globin gene defect
cis deletion - asian
trans deletion - AA
severity - based on number of deletions
4 allele deletion a-thalassemia
see Hb barts - gamma 4
hydrops fetalis
3 allele deletion a-thalassemia
HbH disease
little a-globin
excess B-globin - HbH
B-thalassemia
point mutation splice site - promoter sequences
-decreased B-globin synthesis
mediterranean populations
B-thal minor
heterozygote
low B-chain
increased HbA2
B-thal major
homoygote
B-chain absent
severe anemia - need transfusions
risk of parvo B19 infection
increased HbF - a2 g2 - protective in infant - symptomatic at 6 months
marrow expansion - crew cut - like with sickle cell
lead poisoning
lead inhibit ferrochelatase and ALA dehydratase
decrease heme synthesis
increased RBC protoporphyrin
see basiphilic stippling
buron lines - gingiva
tx of lead poison
chelation
dimercaprol and EDTA
succimer in kids
sideroblastic anemia
defective heme synthesis
X-linked
defect d-ALA synthase
get ringed sideroblasts with iron mito
tx - pyridoxine
pyridoxine
vit B6
cofactor for d-ALA synthase
B12 vs. folate deficiency
B12 - brain - neuro sx
folate - no neuro sx
diphyllobothrium latum
fish tapeworm
lead to B12 deficient
orotic aciduria
cannot convert orotic acid to UMP
-de novo pyrimidine synthesis
defect UMP synthase
auto rec
tx - uridine monophosphate - bypass mutated euzyme
no hyperammoniemia (vs. OTC deficiency)
normocytic anemias
hemolysis - intra and extravascular
anemia of chronic disease
aplastic anemia
LDH
marker for hemolysis - elevated
anemia of chronic disease
inflammation - increased hepcidin - inhibit iron transport
decreased iron
decreased TIBC
increased ferritin
tx - EPO - if chronic kidney disease
aplastic anemia
failure of myeloid stemo cells
- radiation and drugs
- viral
- fanconi - DNA repair defect
get pancytopenia
-dry bone marrow tap
tx - RBC/platelet transfusion or GM-CSF
aplastic anemia drugs
benzene
chloramphenicol
alkylating agent
antimetabolite
hereditary spherocytosis
defect ankyrin, band 3, protein 4.2, spectrin
small round RBC
elevated MCHC and RDW
tx - splenectomy
osmotic fragility test
diagnosis heredtiary spherocytosis
G6PD deficiency
X-linked recessive
heinz body and bite cells
pyruvate kinase deficiency
auto rec
decreased ATP - rigid RBC
hemolytic anemia in newborn
HbC defect
glutamic acid to lysine mutation - B-globin
paroxysmal nocturnal hemoglobinuria
complement mediated RBC lysis
impaired GPI anchor that protect from complement
CD55/59 negative
eculizumab
terminal complement inhibitor
tx for paroxysmal nocturnal hemoglobinuria
sickle cell anemia
point mutation
-glutamic acid to valine - B-chain
deox - HbS sickles
newborn - asymptomatic - bc high HbF
crew cut on X-ray - marrow expansion
heterozygote for HbS
resistant to malaria
autosplenectomy
with sickle cell disease
infection with encapsulated organisms
osteomyelitis in sickle cells
salmonella
tx sickle cells
hydroxyurea - increases HbF
and hydration
warm agglutinin
IgG
chronic anemia with SLE and CLL
cold aggultinin
IgM
-anemia with cold
CLL, mycoplasma pneumona, nononucleosis
coombs test
determine autoimmune hemolytic anemia
determine anti-Ig Abs on RBCs
direct and indirect
microangiopathic anemia
RBC damaged passing narrow lumen
DIC, TTP/HUS, SLE, malignant HTN
see schistocytes
also with prosthetic heart valve
destruction of RBC infections
malaria and babesia
anemia lab values
TIBC - indirect measure of transferrin
transferrin - transport
ferritin - iron storage protein
circulating iron
needed by pathogens to survive
-so body developed way to store iron
anemia of chronic disease
low serum iron
low transferrin
high ferritin
