Anemia 2 Flashcards
Normochromic/Normocytic Anemias (NNA) causes:
w/ ↑ retic count?
w/ normal retic count?
w/ ↑ retic count:
post hemorrhage or recent (not chronic) hemolysis
w/ normal retic count:
+ normal bone marrow = ACD, hypothyroidism, liver dx
+ abnormal bone marrow = myelofibrosis, leukemia, myeloma, metastases, renal failure
Megaloblastic (macrocytic) Anemias caused by?
B12 and/or folate deficiency
B12 and/or folate deficiency result in?
defective DNA synth =
disordered RBC maturation ->
cytoplasmic RNA accumulation ->
large RBCs
Difference in Peripheral Smear and Bone Marrow results for B12 and folate deficiency?
none, they appear identical
What happens if tx B12 deficiency as a Folate deficiency?
Folate replacement alone will correct blood picture, HOWEVER,
must replace B12 also or will results in neuro damage (degen of spinal cord)
Cobalamin (B12) absorption?
Daily requirement?
Binds to IF in stomach ->
released from IF and absorbed in ileum
Cobalamin (B12) daily requirement = 1 - 2 µg
Pernicious Anemia is?
Results in?
Autoimmune disorder causing autoantibodies against gastric parietal cells ->
results in IF deficiency
B12 malabsorption
Other causes of B12 malabsorption? (4)
gastrectomy
iliac dx
bacteria
parasites
Pernicious Anemia clinical findings?
anemia sxs
glossitis
jaundice
splenomegaly
neuro findings: ↓ vibratory and position sense ataxia paresthesia confusion
Pernicious Anemia typical Lab Results:
MCV
Peripheral Smear
B12
other findings
MCV = ↑ (macro)
Peripheral Smear = hypersegmented neutrophilis, Anisocytosis, Poikilocytosis, macro-ovalocytes (large, oval RBCs)
B12 = ↓
other findings =
+ Schilling test,
IF antibodies,
↑ methylmalonic acid AND homocystiene levels
Pernicious Anemia tx?
parenteral B12:
daily x 7d ->
weekly x 4w ->
monthly x life
Folic Acid daily requirement?
Half-life?
200 µg/day (400 - 800 for preggos)
3 wk half-life
Folic Acid deficiency for how long causes anemia?
4-5 months
Causes of Folate Deficiency?
alcoholism end term of pregnancy anticonvulsant therapy malabsorption hemolytic anemias
Folate Deficiency clinical findings?
typical anemia
Folate Deficiency typical Lab Findings?
folate = ↓
methylmalonic acid = normal
homocysteine = ↑
Folate Deficiency tx?
tx underlying cause folate replacement ( 1 mg PO QD or 5 mg if malabsorb)
r/o co-existing B12 deficiency
Hemolytic Anemia is?
early destruction of RBCs
↑ bone marrow production can compensate for early RBC destruction down to how may days?
20 days
(can sustain 2 - 5 times normal RBC production)
RBCs destroyed in less then 20 days, bone marrow can’t compensate
Hemolytic Anemia clinical findings?
typical anemia
jaundice
gallstones (U) bilirubin
↑ risk of salmonella or pneumococcus infections
Hemolysis classifed how? (3)
1) duration (acute/chronic)
2) acquired or inherited
3) main site of lysis
Intravascular vs Extravascular hemolysis?
intra - destruction of RBC in blood stream
extra - destruction of RBC in reticuloendothelial system, (U) spleen
Hemolysis typical Lab Results:
Retic count
Peripheral smear
other findings
Retic count = ↑
Peripheral Smear =
immature RBC,
nucleated RBC,
fragments RBC (schistocytes)
↑ uncong bilirubin
↑ LDH
↑ plasma Hgb
Haptoglobin is?
serum levels of haptoglobin in Hemolysis?
mucoprotein from liver ->
binds Hgb from lysed RBC ->
bound haptoglobin catabolized ->
free haptoglobin ↓
Serum Haptoglobin = ↓ in INTRAvascular hemolysis
Intravascular Hemolysis caused by? (3)
Fragmentation syndromes:
-macro or microangiopathic
Red cell enzyme defects:
-G6PD deficiency
Paroxysmal nocturnal Hgburia
Extravascular Hemolysis caused by? (5)
Hereditary Spherocytosis Sickle Cell Autoimmune Hemolytic Anemia Incompatible blood transfusion Drug-induced
Hereditary Spherocytosis is?
Results in?
auto-dominant disorder
dense RBCs w/ smaller surface area (normal MCV),
RBCs w/ globular appearance and no central pallor,
RBCs trapped in splenic sinusoids
Hereditary Spherocytosis clinical findings?
(U) asymp
mild jaundice/scleral icterus,
splenomegaly
Hereditary Spherocytosis may cause what 2º anemia?
megaloblastic anemia due to inadequate folate:
hemolysis causes need for ↑ folate
Hereditary Spherocytosis test?
Osmotic fragility test:
Defect in RBC membrane results in ↑ RBC destruction when exposed to hypotonic solution
Hereditary Spherocytosis tx?
splenectomy:
RBC lifespan returns to normal,
ends risk of bilirubin gallstones
pneumo vaccine to combat splenectomy’s ↑ risk of infections
Sickle Cell Anemia (SCA) is?
auto-recessive Hgb structure disorder,
RBCs misshaped when deoxygenated
Sickle Cell homozygous vs heterozygous forms?
homo = disease (Hb SS) hetero = trait/carrier (Hb S + Hb A)
SCA epidemiology?
ºBlacks
M=F
SCA signs/sxs?
start 4-6 mo (fetal Hgb ∆ to adult Hgb),
delayed development,
↑ infections
SCA signs/sxs precipitated by? (4)
dehydration
hypoxia
high altitude
intense exercise
SCA chronic hemolysis results in? (2)
aplastic crisis (sudden ↑ in Hgb), bilirubin gallstones
SCA vaso-occlusive ischemic tissue injury results in? (5)
pain crisis, osteonecrosis of femoral/humeral heads, MI, splenic infarc, leg ulcers
SCA typical Lab Results:
Hgb
color/size
Retic count
Peripheral smear
other
Hgb = 5 - 11 g/dl
color/size = normo/normo
Retic count = ↑
Peripheral smear = sickled RBCs, nucleated RBCs, target cells, Howell-Jolly bodies, thrombocytosis
other: Hgb electrophoresis = Hb S
Howell-Jolly Bodies are?
nuclear remnants U removed by spleen (black dots)
SCA tx? (4)
RBC transfusion,
pain management,
hydroxyurea (chemo) to ↓ bone marrow fxn Ѧ pain crisis,
bone marrow transplant
Autoimmune Hemolytic Anemia (AIHA) caused by?
antibodies to RBC ->
fixes complement ->
causes body to destroy cell
RBC w/ antigen/antibody complex destroyed how?
phagocytized by macrophages ->
form spherocytes ->
spleen destroys
Hemolysis tx?
tx cause,
corticosteroids,
splenectomy,
folic acid
Most antibodies to RBC directed against?
ABO/Rh antigens
Coomb’s test detects what?
patient antibodies coating transfused RBCs
Aplastic Anemia is?
acquired bone marrow stem cell abnormality:
total or selective (RBC, WBC, platelets)
Aplastic Anemia etiology?
> 50% idiopathic
20% drug/chemical
10% viral
(P) ionizing radiation
Aplastic Anemia clinical findings?
weakness, infections, bleeding
Pancytopenia (hallmark): anemia, leukopenia, thrombocytopenia
bone marrow = absent precursors
Aplastic Anemia tx?
tx cause, r/o DDx, blood component replacement, bone marrow transplant, immunosuppressant
