RBC Enzyme defects/Immune (Anemia Pt2) Flashcards
Describe G6PD Deficiency
Common?
Linked?
Participates in?
W/O what?
most common hereditary enzyme defect that causes anemia
X-linked
Participates in hexose mannophosphate for NADPH prod
W/O NADPH RBC is vuln. for oxidative damage
What are some consequences of oxidative agents?
denatured Hgb (heinz bodies)
Rbc membrane skeletal structure abnormal
T/F: RBCs with normal G6PD are able to detox oxidative compounds and protect Hgb
true
Describe hemolysis results from heinz body formation
limited to older cells
heme stops after oldest cells die
# retics affect the rate of hemolysis
What are some chemical difficulties with G6PD
(RBC life and morphology)
whatkind of anemia
chronic defect anemia
slightly reduced rbc life span, rbc morph is normal
Describe the hemolytic crisis
anemia is mod to severe
rbc morph changes depend on hemolysis
increased retics - use supravital stain
Describe G6PD flourescense under UV light
no fluorescense and cant preform this after hemolytic lysis
Describe pyruvate kinase Deficiency
Common in?
Source of what?
What is decreased/increased?
Flourescense?
most common def in Embden-meyerhoff pathway
ATP decreased E-M pathway is the source for cellular energy
Increased 2,3 BPG (increased oxy to tissues)
Increased retics
Fluorescnese under UV
Describe Porphyrias
groups of rare anemias hereditary with a error in biosynth
specific enzyme def in accumulation of specific poryphrin tissue
may result in anemia
Describe PNH (proxymal nocturnal hemoblobinuria)
Aquired….
What type of hemolysis
Complement involvement?
Decreased?
aquired myeloproliferative disorder - defective pluripotential stem cell
Intravascular hemolysis
Complement fixes to rbc - lyses
Dec pH
Dec Iron strength
Describe def of Anchor protein in PNH
What is decreased?
What happens at night?
How serious is disease?
GP1 - dec CD55/CD59
slow met. rate at night, respiratory hemolysis
Dec plasma pH
serious disease, pt dies from complications like infections
T/F PNH can lead to aplastic anemia
Hemosiderinuria does not lead to IDA
true
False, it does lead to IDA - thrombocytopenia/infections
T/F rbc/granular analyzed by flow for surface expression of GP1 anchoring proteins
true
Describe Extrinsic abnormalities damaging RBCs
Microanigo Hem. anemia (MAHA)
Rbcs do what?
what kind of course
rbcs pass through fibrin strand/damaged vessicles
Chronic course - DIC - acute condition
What are the two disorders associated with MAHA?
Thrombocytopenia purpura (TPP)
Hem. Uremic synd. (HUS)
Describe Throm. Purpura (TPP)
pentad of findings
hem. anemia w schistocytes
thrombocytopenia
neurological signs
fever/progressive renal failure
T/F TPP does not have plt aggregates
false, it has small plt agreggets
Describe TPP’s Vonwillebrand factor
unusally large VWB factor in TPP occuldes the capillaries in organs
Describe Aquired TPP
and
Inhereted TPP
Aquired: auto-AB to ADAMSTS13 (most common)
Inherited: Varient of TPP caused by ADAMSTS13 Deficiency
Describe HUS
resembles TPP found in young children
triad of findings - MAHA
ACUTE RENAL FAILURE
thrombocytopenia
How do you distinguish between TPP and HUS?
severty of renal failure/absense of neurological symptoms in HUS
What is the typical cause of HUS in children?
E.coli
following enteric infections
toxins - renal capillaries
may set off DIC (local clots dont occur)
may cause plt activation
What are some other causes of non-immune anemias hemolytic?
M
D
F
M
V/B
Malign. hypertension
DIC
fibrin carcinoma
Microoganisms
Venom/burns
Briefly describe immune hemolytic anemias
shortened rbc life caused by an AB
Describe Auto-immune hem. anemia (AHA)
Warm vs Cold reactive
Ab against self
Warm reactive - 37deg most common
Usually IgG
DAT +
Cold reactive optimal at 4 deg (25-30deg)
usually IgM
Describe Cold agglut disease syndrome
Anti what
2nd forms?
Cold weather?
Compl fixation?
DAT/MCHC
Anti-I
2nd forms assoc. with infections
Cold weather - rbc agglut in skin capillaries/local blood stasis
Complete fixation - intravas hemolysis
DAT + 15-32deg MCHC >35
Most common causes for MCHC>36?
spherocytes
Cold Ab Agglut
false inc Hgb result from lipemia/ictureus/hemolysis
Describe Prox. Cold Hemoglobinuria (PCH)
common in?
Assoc
What binds?
What happens with incr temp?
Classic?
kids comon
assoc. with viral infections
IgG binds to rbc at low temps/act complement
Hemolysis when temp increases
Classic -AB- DONATH-LANDSTEINER AB (ANTI-P)
Briefly describe the D-C test
2 samples
1 at 37deg for 60 min
2 at 4deg for 30 then 37deg for 30
(PCH=hemolysis in Tube 2)
Describe Drug induced Hem. anemia
what complex?
Absorbtion?
Describe Haptens role
immune complex w drug/pt Ab/ absorbed into rbc - activates compliment
Hapten: drug non specif bound to rbc - developes anti-drug ab
Membrane modification
drug induced autoab production
Describe Alloimmune Hem. anemia
What rxn?
Delayed vs immediate
Ab against foreign Ab
Transfusion rxn: Immediate - acute intrav hemolysis (ABO)
Delayed - previously formed Ab
low titer not detec on Ab screen
Ab titer increased with second exposure
Describe Hem. disease of the newborn
most frequent Rh-Ab (Anti-D)
ABO incompatible
Usually at birth
first child okay, second and third have issues
How do you detect fetal maternal bleeds?
with acid-elution slide (kleihauer betke)
all hgb can be diluted in acid bath
Hgb F elutes faster than other adult Hgb
Fetal cells pink
How do you quantify Hgb F
flow cytometry - monoclonal ab-anti Hgb F
quick and more precise
HPLL
Nucleus issues mean….
Hgb issues …
Globin problems…
Nucleus - megalonblastic
Hgb - micro/hypo (iron/heme issue)
Globin - thalassemia/hemoblobinopathyies
