Anemia Flashcards
Microcytic Anemia
Iron Deficiency Increased requirements (pregnancy) Poor intake decreased absorption chronic blood loss anemia of chronic disease (late) normoctic early, microcytic later thalassemia sideroblastic anemia other hemoglobinopathies (sickle cell)
Iron deficiency
blood loss
major cause of iron deficiency
occult bleeding more difficult to track down and
usually result of gi blood loss examples:
upper-pepic ulcer, esophageal varices, gastritis
lower-hemorrhoids, diverticula, colorectal caner, ibd (crohns and ulcerative colitis)
Iron deficiency iron stores
normal iron content 3-4 grams
hemoglobin-2 grams
iron containing proteins (myoglobin,..) 400 mg
Iron bound to transferrin- 3-7 mg
remainder is in ferritin or hemosiderin
most iron is in hemoglobin
most ferritin is stored in liver
iron deficiency clinical manifestations
usually presenting sxs in adults are primarily due to anemia include weakness, HA, irritability, and varying degrees of fatigue and exercise intolerance
however many pts are asymptomatic and present only w/ anemia
Pica- cravings for non food stuff
pagophagia-pica for ice (very specific for iron)
sxs are highly dependent on rate of blood loss..the more acute, the more sxs appear. w/ chronic loss, usually takes substantial loss before pt becomes symptomatic
iron deficiency labs
serum ferritin-excellent indicator of iron stores (gold standard test) normal-15-200 ng/ml serum iron (reduce) Total iron binding capacity (increased) transferrin saturation (low)
fe deficiency happens in stages 1. serum ferritin decreases 2. serum iron decreases. 3. TIBC increases
RDW and iron deficiency
RDW measures anisocytosis so looks at variation in size of rbc
Microcytic anemia w/ a low or normal RDW= anemia of chronic disease or thalassemia
microcytic anemia w/ high RDW=iron deficiency
tx of iron deficiency anemia
correct underlying cause
iron supplementation
Anemia of Chronic disease (late)
KEY IS THAT ACD FERRITIN IS HIGH AND IDA FERRITIN IS LOW
SERUM IRON LOW IN BOTH ANEMIA OF CHRONIC DISEASE AND IRON DEFICIENCY ANEMIA, AND TOTAL IRON BINDING CAPACITY IS HIGH IN IDRON DEFICIENCY ANEMIA AND LOW IN ANEMIA OF CHRONIC DISEASE
EPO is low in almost all cases
anemia usually moderate Hb around 7-11
tx of anemia of chronic disease
correction of underlying disorder if possible
pts w/ low epo levels can be given EPO
common diseases associated w/ anemia of chronic disease
RA lupus hiv tb carcinomas lymphomas leukemias
megaloblastic vs nonmegaloblastic
megaloblastic-presence of oval macrocytes and hypersegmented neutrophils
nonmegaloblastic-absence of neutrophil hypersegmentation along w/ the presence of round macrocytes
macrocytic megaloblastic anemias
Abnormalities of dna metabolism
b12 deficiency (cobalamin)
folate deficiency
drug side effects
what separates Folate from B12 deficiency
neurological sxs occur only w/ b12(cobalamin) indicating that additional mechanisms are involved in the central nervous system
what does absorption of b12 depend on 5 factors
adequate dietary intake acid pepsin in the stomach pancreatic proteases gastric secretion of functional IF ileum w/ functioning cobalamin-intrinsic factor receptors
anything that interferes w/ any of these steps can lead to a deficiency in b12 w/ a subsequent anemia and potential neurological sxs
B12 adequate dietary intake
meat and dairy provide b12
total body stores of cobalamin is 2-5 mg, one half which is in the liver, so it takes years to develop vitamin b12 deficiency after absorption of dietary b12 ceases