RBC Disorders (Part 2) Flashcards
(195 cards)
This is a macrocytic anemia in which DNA synthesis is unimpaired.
Macrocytic nonmegaloblastic anemia
Macrocytosis tends to be mild; the MCV usually ranges from100 to 110 fL and rarely exceeds 120 fL
Macrocytic nonmegaloblastic anemia
This macrocytic anemia lacks hypersegmented neutrophils and oval macrocytes in the peripheral blood and megaloblasts in the bone marrow
Macrocytic nonmegaloblastic anemia
Pathologic result of nonmegaloblastic macocytic anemia
liver disease, chronic alcoholism, or bone marrow failure
What are the characteristics of a macrocytic anemia? Cite atleast three. (HIPA)
- Hypercellular Bone Marrow
- Presence of megaloblast
- Ineffective erythropoiesis
- Active intramedullary hemolysis
It is where there is an impaired DNA synthesis and many of the cells never undergo mitosis & rather they breakdown and
die in the bone marrow
Ineffective erythropoiesis
Cite at least three consequences of ineffective erythropoiesis.
- Bone marrow destructions of erythroid presursors
- Lack of regeneration of bone marrow elements during anemic stress
-Lack of nucleated red blood cells in peripheral smear
-Lack of polychromasia in peripheral smear - Reticulocytopenia
- Intramedullary hemolysis
- Increased bilirubin and LDH
- Decreased haptoglobin
What are the two major divisions of megaloblastic anemia?
Vitamin b12 (cobalamin, Cbl) deficiency
Folic acid deficiency
It manifests macro-ovalocytes and giant hypersegmented neutrophils
Megaloblastic anemia
What causes an impaired DNA synthesis?
Vitamin B12 or folate deficiency
If DNA synthesis is impaired what happens?
Nuclear replication slows down and each step of maturation will be delayed
If this is prolonged it would results in a large nucleus. Resulting to a megaloblast, large nucleus, increase cytoplasmic RNA, and early synthesis of hemoglobin
premitotic interval
Cite the megalocyte maturation sequence
Promegaloblast (Megaloblastic rubriblast) >
Basophilic megaloblast (Megaloblastic prorubricyte) >
Polychromatophilic megaloblast (Megaloblastic rubricyte) >
Orthochromic megaloblast (Megaloblastic metarubricyte) >
Polychromatophilic megalocyte (Megaloblastic reticulocyte) >
Megalocyte (Oval macrocyte)
A decrease amount of cells in all cell lines
(WBC, RBC, platelets)
Pancytopenia
Megaloblastic macrocytic anemia results to?
- Pancytopenia
- Increased MCV and MCHC
- Hypersegmented neutrophils (five lobes or
more in segmented neutrophils) - Increased bilirubin
- Increased LDH
- Hyperplasia in the bone marrow
- Decreased M:E ratio (usually 10:1)
- Reticulocytopenia
These are cells found in the bone marrow of a patient
with megaloblastic anemia
Megaloblasts
It is characterized by a more open chromatin
pattern, karyorrhexis, & multiple Howell Jolly
bodies
Megaloblasts
It is a product of maturation arrest or nuclear cytoplasmic asynchrony
Megaloblast
This causes the nucleus
and then cytoplasm to not mature together
nuclear-cytoplasmic asynchrony
Where does cobalamin absorption takes place?
Ileum of the small intestine
It is the only vitamin exclusively synthesized by microorganisms
Cobalamin
Form of stored cobalamin in the liver
adenosylcobalamin
In order to absorb cobalamin, it requires?
Castle’s factor or Intrinsic factor
Cobalamin is transported in the plasma in the form of?
methylcobalamin