Anemias Flashcards
rd blood cell morphology & approach to diagnosis (27 cards)
hemoglobin in the RBC binds to?
Oxygen – to be distributed in the tissues
The term anemia is derived from the greek word?
“anaimia” which means without blood
This is a result of decrease hemoglobin concentration and decrease number of RBC
decrease in oxygen delivery to the tissues; tissue hypoxia
this condition is termed as the decrease in the oxygen-carrying capacity of the blood
Anemia
These are the features that should be evaluated closely during physical examination to provide clues for hematologic disorders in anemia.
Skin for petechiae
Eyes for pallor, jaundice, and hemorrhage
Mouth for mucosal bleeding
Hemoglobin concentration for:
moderate anemias
severe anemias
moderate: 7-10 g/dL
severe: less than 7 g/dL
Severity of anemia is gauged by
- degree of reduction in hemoglobin
- cardiopulmonary adaptation
- rapidity of progression of the anemia
How do the body compensate for the decreased number of oxygen delivered to the tissue caused by decreased hemoglobin concentration?
the condition elicits an increase in erythropoietin secretion by the kidneys. This will then stimulate the RBC precursors in the bone marrow, thus releasing more RBCs into the circulation.
Life span of RBC in the circulation
120 days or 4 months
Nutritional factors necessary in adequate RBC production
- Iron, vitamin b12, and folate.
Differentiate hematopoiesis from erythropoiesis
Haematopoeisis describes the production of cells that circulate in the bloodstream including red blood cell, platelets, and all types of white blood cell. Consequently, erythropoiesis is the process by which red blood cells (erythrocytes) are produced
Hormone that controls the regulation of erythropoiesis
- Erythropoietin (produced by the kidney)
This refers to the production of erythroid precursor cells that are defective
a. ) Insufficient erythropoiesis
b. ) Ineffective erythropoiesis
c. ) Effective erythropoiesis
B. Ineffective erythropoiesis
This refers to a decrease in the number of erythroid precursor cells in the bone marrow, resulting in decreased RBC production and anemia
a. ) Insufficient erythropoiesis
b. ) Ineffective erythropoiesis
c. ) Effective erythropoiesis
A. insufficient erythropoiesis
What happens to cells in ineffective erythropoiesis
-They undergo apoptosis (programmed cell death) in the bone marrow before they can mature into reticulocyte stage and be released into circulation
Laboratory Diagnosis of Anemia
CBC - Complete blood count determine:
- RBC count
- Hgb concentration
- Hematocrit
- Platelet count
- RBC indices such as
- MCV (mean corpuscular volume)
- MCH (mean cell hemoglobin)
- MCHC (mean cell hemoglobin conc.)
This is a measure of the average RBC volume in femtoliters (fL). This also measured the average size of your RBC.
MCV- mean corpuscular volume
What does it mean when your MCV is high?
If someone has a high MCV level, their red blood cells are larger than usual, and they have macrocytic anemia.
This is the coefficient variation of RBC volume expressed as percentage. It also indicates variation in RBC volume within the population .measured.
RDW - red cell distribution width
Note: an increase RDW correlates with anisocytosis in the peripheral blood film
This serves as an important tool to assess the bone marrow’s ability to increase RBC production in response to anemia
Reticulocyte count
These are young RBCs that lack a nucleus but still contain residual RNA to complete the production of hemoglobin
- Reticulocyte
The time it takes for reticulocyte to mature to RBC (erythroid) in the peripheral circulation
- 1 day
Adult reference interval for Reticulocyte count
0.5-2.5 % expressed as percentage of the total number of RBC
Newborn interval for reticulocyte count
1.5-6.0% but gradually changes to an adult interval after few weeks of birth.
