RBC and Anaemias (part 2) (Panopto video link) Flashcards
Broadly speaking, what does a complete blood count consist of?
- Haemoglobin
- White Blood Cells
- Platelet count
- Red Blood Cells count
What are the factors pertaining to red blood cells assessed in a complete blood count?
- Red Blood Cells (RBC)
- Haematocrit (HCT)
- RBC indices (MCV, MCH, MCHC)
For anaemia, what 3 factors pertaining to red blood cells should you focus on?
- haematocrit (HCT)
- haemoglobin (Hb)
- mean cell volume (MCV)
What is the packed cell volume also called?
Haematocrit
What is haemoglobin a direct indication of?
Oxygen transport capacity
Describe the relationship between haemoglobin and anaemia
Haemoglobin is proportionately low in anaemia
What does haematocrit (packed cell volume) refer to?
The percentage of blood composed of erythrocytes (red blood cells)
What does mean cell volume measure?
The average volume of a single red blood cell
What is a standard haematocrit (packed cell volume)?
0.46
What is a standard haematocrit (packed cell volume)?
0.46
What is a standard haematocrit (packed cell volume)?
0.46
What does mean cell haemoglobin refer to?
Haemoglobin divided by the RBC count
What does mean cell haemoglobin concentration refer to?
Haemoglobin divided by the haematocrit
What does mean cell haemoglobin concentration refer to?
Haemoglobin divided by the haematocrit
What does red cell distribution width refer to?
It is a measure of variability in the size of red blood cells
How does anaemia of chronic disease affect red cell distribution width (RDW)?
It is normal in anaemia of chronic disease
What is the usual range for red cell distribution width?
<15%
What is a condition in which red cell distribution width (RDW) is increased?
Iron deficiency
How does anaemia of chronic disease affect red cell distribution width (RDW)?
It is normal in anaemia of chronic disease
What is the standard formula for determining red cell distribution width (RDW)?
Standard deviation of mean cell volume (MCV) * 100
What is the reference range for red cell distribution width (RDW)?
11.5% to 14.6%
If the mean cell volume (MCV) is high and the red cell distribution width (RDW) is normal, what are the two likely causes?
- Alcohol/liver disease
- Bone marrow problem (caused by chemotherapy or aplastic anaemia)
What are the cellular components of blood derived from?
Pluripotential stem cells in the bone marrow
What is the lifespan of reticulocytes?
1 to 2 days
What is the lifespan of reticulocytes?
1 to 2 days
What is the lifespan of red blood cells (erythrocytes)?
120 days
What is the reticulocyte count an indirect measurement of?
Red blood cell (erythrocyte) production
What is the reticulocyte usually equivalent to?
Approximately 1% of the red blood cell count (RCC) in the basal state
When will reticulocyte count not be increased?
When red blood cell (erythrocyte) count is deficient
When will reticulocyte count not be increased?
When red blood cell (erythrocyte) count is deficient
In anaemia, what does the reticulocyte count reflect?
Both the increased production and reduced number of red blood cells (erythrocytes)
What is a correct reticulocyte count adjusted to?
A normal haematocrit (HCT)
What does the reticulocyte count depend on?
The type of anaemia
When may reticulocyte count be increased?
In acute blood loss
When will reticulocyte count not be increased?
When red blood cell (erythrocyte) is deficient
What are 3 causes of deficient red blood cell (erythrocyte) production?
- Folate deficiency
- Iron deficiency
- Vitamin B12 deficiency
What can reticulocyte count be used to monitor?
Response to the treatment of anaemia
What can reticulocyte count be used to monitor?
Response to the treatment of anaemia
What laboratory value will reflect megaloblastic anaemia?
A large mean cell volume (MCV)
What is sickle cell anaemia?
A condition by which the body forms odd-shaped red blood cells (erythrocytes) and thus has reduced capacity to carry oxygen around the body.
Describe the lifespan of red blood cells (erythrocytes) in sickle cell anaemia
Sickle cells usually die in 10 to 20 days (compared to 120 days for healthy red blood cells (erythrocytes))
Describe the lifespan of red blood cells (erythrocytes) in sickle cell anaemia
Sickle cells usually die in 10 to 20 days (compared to 120 days for healthy red blood cells (erythrocytes))
What is a secondary complication of sickle cell anaemia besides anaemia?
The sickle cells can get stuck in small blood vessels, causing pain
What occurs to iron in sideroblastic anaemia?
The body has iron available but cannot incorporate it into haemoglobin (Hb)
What is sideroblastic anaemia?
A rare, refractory anaemia caused by microcytic hypochromic cells in peripheral blood, with ring sideroblasts in bone marrow and excess iron
What are 6 causes of secondary sideroblastic anaemia?
- Drugs
- Alcohol
- Lead poisoning
- Myeloproliferative disorders
- Leukaemia
- Connective tissue disorders