Red Blood Cell Diseases Flashcards
What are the 8 parts with units of a full blood count?
- WBC - white blood cell count (x10^9/L)
- RBC - red blood cell count (x10^12/L)
- Hb - haemoglobin concentration (g/L)
- Hct - haematocrit = % of blood that is rbcs (%)
- MCV - mean cell volume (fL —> 10^-15)
- MCH - mean cell haemoglobin (pg —> 10^-12)
- MCHC - mean cell haemoglobin concentration (g/L)
- Platelet count (x10^9/L)
How do you calculate MCV?
MCV = Hct/RBC x 1000
- think about units 10^-9L = 10^-12L x 1000
How do you calculate MCH?
MCH = Hb/RBC
∵ Hb per RBC = total Hb / no. RBCs
g/L = g/L / no.
How do you calculate MCHC?
MCHC = Hb/Hct
∵ Hb conc per RBC = total Hb / proportion of RBCs
g/L = g/L / % no.
How are blood cell counts performed now?
Automated instruments
- cell flows between light source and sensor/through electric field —> electronic impulses
What are the 2 indicators of anaemia on a FBC?
- Low Hb
- Low MCV
Which 4 features of erythrocytes distinguish the type of anaemia on a blood film?
- Size (microcytic, normocytic, macrocytic)
- Shape
- Colour (pale, polychromasia)
- Poikilocytes - abnormal shapes
How is iron deficiency anaemia indicated on a FBC? (4)
- Low Hb
- Low MCV
- Low MCH
- Low MCHC
(5. High transferrin)
How is iron deficiency anaemia indicated on a blood film?
Microcytic erythrocytes (small and pale)
How is thalassaemia trait identified on a blood film?
Microcytic erythrocytes (small and pale)
What is anaemia?
Low Hb
What is thalassaemia?
Abnormal Hb production leading to anaemia
Which 2 lab techniques can be performed to see the presence of different Hbs in blood?
Hb electrophoresis
HPLC (high performance liquid chromatography)
What is the electrophoresis pattern of Hb?
HbA
HbF
(HbS)
HbA2
How is anaemia of chronic disease indicated on a FBC with transferrin and protein measures?
- Low Hb
- Low MCV
- Low transferrin
- High C-reactive protein
How is thalassaemia trait indicated on a FBC?
- Low Hb
- Low MCV
- Low MCH
What are the 4 common causes of microcytic anaemia and why?
- Iron deficiency anaemia
- Anaemia of chronic disease
- α-Thalassaemia
- β-Thalassaemia
How is megaloblastic anaemia indicated on a blood film?
Macrocytic erythrocytes