Exam 2 Flashcards
What are Microcytic Hypochromic Anemias?
RBC disorder w/ defective Hgb synthesis b/c iron deficiency or abnormal utilization of iron
Group of red cell disorders that involve a defect in hemoglobin synthesis due to a deficiency of iron or an abnormal utilization of iron.
also include globin chain synthesis disorders which contribute to anemias known as thalassemias
What anemias are classified as an Microcytic Hypochromic Anemia?
iron deficiency anemia (IDA), anemia of chronic disease (ACD) and sideroblastic anemia
What is erythropoiesis?
hemoglobin synthesis
What three compounds are required in hemoglobin synthesis?**
iron, globin, and protoporphyrin
What is in a hemoglobin molecule?
- four heme groups
- four globin chains
What is in a heme group?
- a protoporphyrin ring
- iron molecule
What are other names for stored iron in the body?
- ferritin
- hemosiderin
Where is iron found in the body?
2/3 = hemoglobin molecules
1/3 = storage pools of the bone marrow, liver and spleen
What are ferritin levels monitored for?
an indicator of how much iron is stored in the body
What are hemosiderin levels monitored for?
precipitated aggregates of ferritin and is less readily available for use
Why are iron levels decreased during menstruation, pregnancy and breast feeding?
menstruation = blood loss
pregnancy, breast feeding = baby takes a portion of the iron from the mom (mom takes iron pills)
During what age do you have a large requirement/need for iron?
infancy and adolescence
What is Transferrin? **
a single chain glycoprotein with two iron binding sites
What is the function of transferrin? **
an iron binding transport protein in plasma and extracellular fluid
Why is hemosiderin less available to the body compared to ferritin?
Hemosiderin is NOT water soluble.
Ferritin is water soluble and can be easily accessed.
How are you able to see hemosiderin?
it is the blue bits of iron seen in tissue using PRUSSIAN BLUE stain
What lab tests are ordered to evaluate iron?
Iron, Total Iron Binding Capacity or (TIBC), Transferrin, % saturation and ferritin
What type of iron is measured for serum iron?
transferrin bound iron
(the maximum amount of iron that is bound in plasma or serum)
What is Total Iron Binding Capacity (TIBC)?
the total amount of Iron that can be bound by transferrin in the plasma or serum
(potential iron that can be bound to transferrin in the serum)
What is the formula for percent (serum iron) saturation?
% saturation= serum iron/TIBC X100%
Ferritin ______-proportional to the amount of iron that is stored.
directly
(ex. low ferritin = iron depletion)
In what conditions are ferritin increased?
inflammatory states, malignancy, infections and in liver disease
Serum transferrin ______-proportional to the amount of iron that is stored.
inversely
(serum transferrin decrease = stored iron increased)
What is iron deficiency anemia?
- A microcytic hypochromic anemia
- Most common anemia (esp. in women)
- Due to a lack of adequate iron stored in the body
What can cause iron deficiency anemia?
- increased need of iron or abnormal utilization for iron
- increased blood loss, poor diet or malabsorption
- excessive loss of iron from the body due to blood loss (bleeding, ulcers, etc.)
What is the most common cause of iron deficiency anemia in elderly patients?
blood loss from the GI tract
What is the most common cause of iron deficiency anemia in women?
menstruation
What are symptoms of (acute) iron deficiency anemia?
fatigue, irritability, headache, weakness, pale skin or pallor
What are symptoms of (severe) iron deficiency anemia?
sore tongue, spooning of the nails, and or muscle dysfunction
In iron deficiency anemia, what is decreased?
MCV, MCH and MCHC most likely is decreased
Reticulocyte is decreased as a result of ineffective erythropoiesis.
In iron deficiency anemia, what can be seen on a stained peripheral blood smear?
- anisocytosis due to increased red cell distribution width (RDW)
- microcytic, hypochromic erythrocytes
- target cells
- elliptocytes or ovalocytes
- tear shaped RBC’s
How do you treat iron deficiency anemia?
- Correcting the primary cause
- Oral iron supplements
- Iron therapy may be given IV or by injections/infusion
What is another name for Anemia of Chronic Disease?
Anemia of Inflammation (AOI)
What is the second most prevalent disorder after Iron Deficiency Anemia (IDA)?
Anemia of Chronic Disease
What other illness are associated with Anemia of Chronic Disease?
chronic infections, autoimmune disease, chronic inflammation and malignant neoplasms
What is decreased with Anemia of Chronic Disease?
- serum iron levels
- decreased TIBC (total iron binding …)
- decreased saturation of transferrin
- sideroblasts
What is increased with Anemia of Chronic Disease? and why?
Serum ferritin levels are increased due to iron being trapped in the RES cells of the bone marrow.
What causes Anemia of Chronic Disease?
ACD is the result of an activated immune system with the production of cytokines.
The cytokines and the RE cells affect changes in iron hemostasis
What is the treatment for Anemia of Chronic Disease?
- Includes treating the underlying disease first
- Blood transfusions are administered for a fast intervention. (increase hemoglobin)
- Erythropoietic agents are recommended.
- Stimulation of iron uptake and heme biosynthesis in the erythroid cells
What are the characteristics of Sideroblastic Anemias?
- hypochromic anemia
- ineffective erythropoiesis
- an increase in serum iron and tissue iron
- the presence of sideroblasts in the bone marrow
- abnormalities of the enzymes regulating heme synthesis
What are primary acquired sideroblastic anemias called?
idiopathic
What are common causes of secondary sideroblastic anemia?
- drugs
- toxins (esp. Lead poisoning)
What is commonly seen in blood smears of people with sideroblastic anemia?
- poikilocytosis
- anisocytosis
- target cells
- pappenheimer bodies(iron deposits)
- basophilic stippling
What will you see on blood smears of people with lead poisoning? **
- coarse basophilic stippling of the RBCs
- increased reticulocytes
What is seen in the iron evaluation with sideroblastic anemia?
- increase in serum iron
- increased ferritin
- normal to decreased TIBC
- increase in percent saturation levels.
What is seen in the bone marrow with sideroblastic anemia?
ringed sideroblasts
How do you treat sideroblastic anemia?
- establish whether it is hereditary or acquired
- if acquired by drugs/medication, discontinuing the drug/meds will cause a fast improvement
What is iron overload?
the accumulation of excess iron in the reticuloendothelial cells in different tissues
What is hemochromatosis?
a disorder that causes tissue damage due to excess iron
Where is excess iron stored?
liver, heart, and pancreas and therefore damages the organs
Hereditary Hemochromatosis is a _______ genetic disorder that is common in ______ populations.
- recessive
- white/caucasian
What diseases can be acquired due to excess accumulated iron in the tissues?
chronic liver disease, arthritis, diabetes, pituitary damage, and cardiac arrythmias
What are the characteristics of megaloblastic anemia?
defective nuclear maturation that is caused by defective deoxyribonucleic acid (DNA) synthesis
Is megaloblastic anemia a microcytic or macrocytic anemia?
macrocytic anemia
What will be seen in the blood smear of megaloblastic anemia?
megaloblasts: large and abnormal red cell precursors
What are symptoms found with megaloblastic anemia?
fatigue, weakness, shortness of breath, and congested heart failure
What is a (macroscopically visible) symptom of SEVERE megaloblastic anemia?
a lemon yellow tint skin (jaundice) which comes from an increased bilirubin level.
What is megaloblastic anemia associated with?
ineffective erythropoiesis and hemolysis.
What is the MCV range for megaloblastic anemia?
100-116 fL
What would be increased with megaloblastic anemia (ineffective erythropoiesis) in the bone marrow?
increased erythrocyte precursors
What would be increased with megaloblastic anemia (ineffective erythropoiesis) in the bone marrow?
increased erythrocyte precursors
What would be decreased with megaloblastic anemia (ineffective erythropoiesis) in the peripheral blood smear?
- decreased red cell release
- decreased reticulocyte count
What RBC morphology would be present with megaloblastic anemia?***
- ** Multilobed neutrophils/hyper-segmented neutrophils (5-10 lobes) **
- schistocytes
- spherocytes
- target cells tear shaped RBCs
What are the two major causes of megaloblastic anemia? (that aren’t drug induced)
- Vitamin B12 deficiency
- Folic acid deficiency
( or a combination of both)
What kind of drugs induce megaloblastic anemia?
drugs that interfere with the metabolism of either vitamin B12 or folic acid
What can cause B12 deficiency?
- Inadequate dietary intake
- Inadequate production of intrinsic factor (Pernicious anemia)
- Malabsorption (Disorders in absorption)
What can cause Folate deficiency?
- Inadequate dietary intake
- malabsorption
- Excess demand(pregnancy, infancy)
- Drugs such as Phenytoin (seizure meds)
What is the most common cause of pernicious anemia?
vitamin b12 deficiency
What is necessary for vitamin b12 absorption?
intrinsic factor
What can cause decreased intrinsic factor (IF)?
gastric parietal cell atrophy