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Flashcards in Anemia Deck (39):
1

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)

2

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)

3

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

4

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

5

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

6

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

7

tx of iron deficiency anemia

correct underlying cause
iron supplementation

8

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

9

tx of anemia of chronic disease

correction of underlying disorder if possible
pts w/ low epo levels can be given EPO

10

common diseases associated w/ anemia of chronic disease

RA
lupus
hiv
tb
carcinomas
lymphomas
leukemias

11

megaloblastic vs nonmegaloblastic

megaloblastic-presence of oval macrocytes and hypersegmented neutrophils
nonmegaloblastic-absence of neutrophil hypersegmentation along w/ the presence of round macrocytes

12

macrocytic megaloblastic anemias

Abnormalities of dna metabolism
b12 deficiency (cobalamin)
folate deficiency
drug side effects

13

what separates Folate from B12 deficiency

neurological sxs occur only w/ b12(cobalamin) indicating that additional mechanisms are involved in the central nervous system

14

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

15

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

16

what can interfere w/ the dietary intake of b12

vegan diet

17

what interferes w/ acid pepsin in stomach

gastrectomy/bariatric surgery, gastritis

18

what interferes pancreatic enzymes

pancreatic insufficiency

19

what interferes w/ IF secretion

pernicious anemia

20

what interferes w/ absorption in ilium

absorption interference: crohns or ileal resection

21

pernicious anemia

autoimmune
parietal cells in stomach fail to secrete enough IF to ensure intestinal absorption of b12
sx- weakness, glossitis (enlarged, smooth tongue), paresthesias, gi sxs-diarrhea, N/v, and pain, severe anemia can reveal signs of cardiac failure

22

eval of pernicious anemia

review pts drug list
measure of serum b12 and folate
smear to look for megaloblasts (macroovalocytes) and hypersegmented neutorphils

23

how to tell from labs folate vs b12

specific metabolites (methylmalonae and homocysteine)
serum conc of homocysteine as well as serum and urinary conc of methylmalonic acid are elevated in b12 deficiency due to a decreased rate of metabolism

only Homocysteine is elevated in folate deficiency since folate does not participate in methylmalonic acid metabolism

antibodies to IF

24

Tx of B12 deficiency

parenteral or sublingual b12
vegans can take oral therapy cause they don't have absorption problem 25-100 micrograms
IMPORTANT- a person treated w/ folate who has a b12 deficiency may have their sxs masked...which is bad news cause neurological damage form b12 deficiency can be irreversible so have to make sure you find the underlying problem

25

folate deficiency

comes form animal products and leafy vegetables
folate stores are low can develop megablastosis within 4-5 months
MOST COMMON CAUSE OF of folate deficiency is nutritional due to poor diet and/or alcoholism
other causes include increased requirements in pregnancy and w/ pts w/ hemolytic anemia
drugs also interfere w/ folate metabolism (trimethoprim, methotrexate, phenytoin)

26

nonmegaloblastic macrocytic anemias

alcoholism
liver disease
aplastic anemia
drug induced
myelodysplastic syndrome
pregnancy
myeloma
hypothyroidism

27

cells characteristic of liver disease

target cells-area of central density surrounded by a halo of pallor.

28

Diff Diagnosis for normocytic anemia

N=normal preg
o=over hydration
r-renal disease (lack of epo)
m=marrow problems, mixed anemia
a=acute blood loss
l=liver disease (can be macrocytic)
si=systemic inflammation (anemia of chronic disease (early)
z=zero prod (aplastic anemia (can be macrocytic))
e=endocrine disorder
hemolytic anemias

29

anemia of chronic renal failure

don't confuse w/ anemia of chronic disease
tx- Human recombinant EPO (procrit)

30

Mixed Anemia

very important to order a smear cause MCV will be normal
if have microcytic cells from iron deficiency and macrocytic cells from a b12 deficiency the MCV may be normal
RDW would be increased

31

Reticulocytes

young immature RBC that contain residual RNA, which explains their tendency to stain w/ certain dyes
make up 1% of rbc
circulate 1 day before maturing to rbc

32

what does reticulocyte count represent

ability of bone marrow to produce mature rbc
normal 1-2%
In an anemic pt an increase in the reticulocyte count provides evidence that the bone marrow is adequately responding to the anemia (in an effort to maintain the hemoglobin level)
have blue stains on smear

33

Reticulocyte count

very useful in context of a normocytic anemia
3 situations
acute blood loss
hemolytic anemia
response to iron, folate, or b12 replacement

34

Anemia of acute blood loss

initially hemoglobin is normal but after time hemoglobin will fall
Retic count will be normal for the first few days but will increase shortly after

35

Hemolytic anemias

RBC destruction
marrow prod can't compensate for rbc destruction
extravascular (spleen, liver, marrow)
intravascular (rare)
intrinsic abnormalities of rbc
contents (Hb, enzymes)
membranes
extrinsic to rbc
serum antibodies
traumas in the circulation
infectious agents

36

Extravascular destruction of rbc- Intrinsic defects

Enzyme deficiencies (G6PD or pyruvate kinase)
Hemoglobinopathies (sickle cell, thalassemia,
unstable hemoglobin
Membrane defects (hereditary spherocytosis,
elliptocytosis)

37

extravascular destruction of rbc-extrinsic defects

Liver disease
hypersplenism
infections
oxidant agents
other agents (snake bites, lead, etc)
microangiopathic (DIC, TTP)
Autoimmune hemolytic anemia
intravenous immune globulin infusion
large granular lymphocyte leukemia

38

what is main sx of hemolytic anemia

jaundice

39

tests for hereditary spherocytosis

Reticulocyte count elevated
MCHC (mean corpuscular HgB conc)-most helpful
osmotic fragility testing
ektacytometery
acidified glycerol lysis test
cryohemolysis test
eosin 5 maleimide binding test