pathophysiology Flashcards
what is anemia?
- reduction in RBC
- low hemoglobin concentration
- low O2 carrying capacity leads to hypoxia which is inadequate to support normal metabolism
what are some causes of anemia ?
- blood loss
- decreased defective production
- excessive destruction of blood cells
what is microlytic cells?
smaller than normal rbc
mean corpsular volume 80-100fL
iron deficency anaemia
thalassemia
what is normocytic blood cells?
normal sized but too little in production
anemia of chronic disease (kidney disease, rheumatoid arthritis and chrons disease)
aplastic anemia
haemolytic anemia
sickle cell anemia
what is macrolytic cell?
too large rbc
vitamin B12 and folate deficiency
megaloblastic anaemia
alcohol/ liver disease
what are some causes of iron deficiency anemia ?
- loss of iron (due to bleeding)
2. decreased iron uptake (malabsorption due to chronic disease)
what is iron deficiency anemia ?
iron lost from the body stores and insufficient hemoglobin are being produced
what are the blood test to diagnose iron deficiency anemia ?
- decrease rbc count
- decrease haemoblobin
- decreased serum iron and ferritin
- increase iron binding capacity ( bind iron to transferrin)
- increase red blood cell distribution (test volume and size)
what are the symptoms specific to iron deficiency?
kolionychia (spooning) angular stomatitis (iron deficiency cause insufficient myoglobin formation) , redness on side of mouth
what is vit b12 folate deficiency?
vit B12 and folate is absent to produce healthy red blood cells(megaloblast form but cannot divide)
resulting in pernicious anemia (auto immune damage to parietal cell)
what are vit b12 and folate used for?
normal DNA synthesis and reduce birth defects in unborn babies
what are some reasons for reduced intake of vit b12 ?
- diet (found in food of animal origin)
- impaired absorption ( lack of intrinsic factor produced by parietal cells)
- impaired absorption due to disease affecting the ileum (crohn)
- increased parasitic uptake
who are some people that require more B12 ?
pregnancy
hyperthyrodism
disseminated cancer
what are some symptom specific to pernicious anemia ?
not really
what is thalassemia?
it is inherited by gene mutation
result in decreased production of alpha and beta globin chains
what is alpha thalassemia?
reduced production of alpha globin chains
excessive globin chain
less common
what is beta thalassemia ?
reduced production of beta globin chains
excessive alpha glucose chain
more common, inherited in autosomal recessive pattern
what is beta thalassemia major?
2 error genes
and will die easily
what are some symptoms specific to thalassemia major ?
- hair end of skull
due to alpha globin in excess, itll lead to hemolysis(destroy) alongside with decrease Erythropoiesis
leads to anemia
body compensate by increasing EPO
there will be increase bone marrow activity and increased iron absorption
lead to
1. iron overload
2. liver toxicity
3. bone deformity
4. hepatomegaly as the rbc will tend to be destroyed and then it will go to the spleen and it will cause spleen enlargement
what is minor thalassemia ?
one normal gene and one defective gene
will cause mild anemia
what are the possible treatment for thalassemia?
frequent blood transfusion to keep Hb level high but not iron
give vitamin C
splenectomy
bone marrow transplant
what is sickle cell anemia?
it is inherited point mutation in BETA chain
glutamic acid is replaced by valine
autosomal recessive (only those with two HBS alleles)
when O2 is low, HBs will polymerize to form a rigid sickle cell called RBC
what are the characteristic of sickle cell rbc ?
insoluble in blood
unable to easily pass through smell arteries
cause cell membrane of rbc to become damaged and die easily
what are the symptoms that are specific to sickle cell anemia?
blockage of arteries :tissue damage, infractions , pain and loss of function
short life span of RBC : hyperbilirubinemia and jaundice
what is aplastic anemia?
stem cell disorder in which fatty marrow is replaced with reduced hemopoietic tissue (pancytopenia)
results in low count for all types of cells
wbc rbc and platelets
what are some causes of aplastic anemia?
toxcicity radiation immunologic injury to the bone marrow stem cells chemotherapy viral infection (dengue)
what are the symptoms specific to aplastic anemia?
decreased wbc result in infection
decrease platelets results in
1. petechiae , is red spots on the skin caused by capillaries bleeding
2. hemorrhage , is massive internal bleeding