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
what is anemia of chronic disease?
failure of renal endocrine system to produce epo
therefore decrease in rbc
what are the treatment for anemia of chronic disease?
dialysis
administration of EPO
what is polycythemia ?
abnormally high rbc mass with hematocrit greater than 54% in males and 47% in females
what is absolute polycythemia?
increase in rbc due to the increase in rbc production
1, primary
2. secondary
what is relative polycythemia ?
increase in rbc mass without a increase in production of rbc
underlying cause of reduced plasma fluid volume resulting in higher hematocrit
caused by water deprivation, excessive diuretic usage or gastrointestinal losses
what is primary polycythemia vera?
due to done marrow disorder, lead to increase blood volume and viscosity
absolute increase in rbc, wbc and platlets (all blood cells)
what is secondary polycythemia vera?
physiologic changes that increases the body demand for oxygen
increase rbc due to more O2 needed by the body
due to
- living at high altitude
- lung disease
- severe obesity
- defective O2 transport
what is hematocrit test?
measures the proportion of red blood cells in your blood
what is MCV test? (mean corpuscular volume)
MCV blood test measures the average size of your red blood cells, also known as erythrocytes.
what is MCH test? (mean corpuscular hemoglobin)
average amount in each of your red blood cells of a protein called hemoglobin, which carries oxygen around your body.
what is MCHC? (mean corpuscular hemoglobin concentration)
checks the average amount of hemoglobin in your blood. Your doctor may use both measurements to help in a diagnosis of anemia.
what is MPV test? (mean platelet volume)
measures the size of your platelets, which are blood cells that help with clotting.
what is RDW test? (red cell distribution)
measures the differences in the volume and size of your red blood cells (erythrocytes).
what are the different test results that reflect iron deficiency anemia?
overall :
low rbc , haemoglobin
- haematocrit: low
- MCV: low
- MCH low (average volume of haemoglobin within a rbc)
- MCHC : low
- RDW : high ( difference in sizes)
- low ferritin (iron is stored as ferritin)
- total iron binding capacity : high (it directly measures transferrin. transferin binds to iron and allow iron to be absorbed, when there is not enough iron, the body produces more transferin)
- serum iron low
what are some test to test for pernicious anemia?
- MCV : increased (macrocytic rbc are formed)
- RDW : high ( different in sizes)
- low serum B12
schilling test will also be conducted to determine how well the body can absorb vit B12
what are some diagnostic test used to test aplastic anemia?
low wbc
low platelets
low neutrophils
what are some test used to test absolute polycythemia?
high wbc
high rbc
high platelets
what are some test used to test for relative polycythemia?
only increase in rbc and haemoglobin
what are the findings of blood film test for iron deficiency anemia?
1, microcytic (smaller than usual)
2. hypochromic (less hemoglobin, less colour under microscope)
what are the treatment for insufficient iron intake?
give oral iron
what are the treatment for heavy mensural bleeding?
- hormonal therapy (oestrogen progestin therapy) by regulating the mensural cycle
- antifibrinolytic (transexamic acid) to reduce fibrinolysis
what to do to treat anemia of chronic kidney disease?
recombinant human epo to increase production of RBC
decreases the need for rbc transfusion
what are the causes for bleeding disorder?
- decrease in platelet function
- decrease in number of platelet
- abnormal clotting factors
what is the normal count of platlet ?
150000-400000 platelets / mm cube of blood
what is the possible cause of bleeding if there is a family history of bleeding in both males and females?
von willebrand disease
family history of bleeding in males ?
hemophilia A or B
newly acquired bruising?
might be due to drugs like aspirin, NSAID, anticoagulant
excessive bleeding / bruising during or after surgery ?
mild severe deficiency of coagulation factors
bleeding following initial hemostasis ?
factor XII deficiency
what is thrombocytopenia?
low platelet count, lead to both superficial and internal bleeding
can be inherited
what are some causes of thrombocytopenia ?
- decreased platelet production
- decreased platelet survival
- splenic sequestration
- platelet dilution
- massive transfusion of blood in the past 24 hours
what are the symptoms of thrombocytopenia?
- bleeding from gum and nose
- prolonged bleeding
- purpura ( purple patches on skin)
- petechiae (round spots)
- ecchymosis (bruise)
- blood in urine or stools
- unusal heavy mensural flow
- fatigue
- enlarged spleen
what are the blood test to test for thrombocytopenia ?
full blood count show low platelet count
what is thrombocytosis ?
platelet count more than 400,000mmcube
what are some causes of thrombocytopenia?
- transitionary : stress/ physical exercise
- primary : polycythemia vera and chronic granulocytic leukemia
- secondary : response of haemorrhaege and infection
what is clotting disorder?
abnormal bleeding due to defects in the clotting cascade or fibrinolytic process
what is hemophillia A ?
X linked recessive , seen with males with only 1 and females need to have both
carriers can also have bleeding symptoms
due to decreased factor VIII (8)
MORE COMMON
what is hemophillia B?
christmas disease
due to decrease in factor IX 9
what are the signs and symptoms of hemophillia ?
- easy bruising (ecchymosis)
- hematuria (blood in urine)
- hemathrosis (knee werid)
- stroke
- increased intracranial pressure
what is the treatment for hemophillia ?
- inject the missing recombinant factor
- avoid contact sport
- avoid aspirin
what is disseminated intravascular coagulation (DIC)?
a rare and serious condition that disrupts your blood flow. It is a blood clotting disorder that can turn into uncontrollable bleeding.
trigger event cause overconsumption of clotting factors which lead to excessive bleeding
what are some lab test for DIC ?
- platelet count decreased
- fibrinogen count decreased
- prothombin time increase
- partial tromboplastin time increase
- d dimer increase
