PATHOLOGY- Blood disorders Flashcards
What are the 2 major components of blood
- Formed elements (45%)
- Plasma (55%)
What makes up the plasma in blood?
- Water
- Plamsa proteins
- Regulatory proteins
- Other sources
What makes up the formed elements of blood?
- Erythrocytes (99%)
- Leukocytes
- Platelets
What is another name for the former elements of blood?
Cellular component
What is hematocrit?
The proportion of whole blood that is made up of red blood cells
what is the equation to work out the haematocrit
% RBC / ratio of RBC volume to total BV
what is another word for haematocrit
packed cell volume (PCV)
What percentage of the blood is made up of hematocrits?
42-47%
What is the difference between plasma and serum
Plasma includes fibrinogen
Serum is plasma without fibrinogen (e.g. after blood clot)
What is the function of blood?
- Transportation of gases, waste, hormones and enzymes
- Fighting infection
- Homeostasis (Temperature, pH, volume)
- Haemostasis
How does the blood help with fighting infections?
It carries antibodies and leukocytes to site of infection
What is haemostasis?
Blood clotting
What is anaemia?
Haemoglobin concentration that is below a reference range for sex and age
usually a loss in RBC mass
when are there apparent [Hb] changes
when there are changes in plasma volume
plasma vol dec=apparent inc[Hb]
plasma vol inc=apparent dec[Hb]
how do you classify anaemia
By red cell size / volume (MCV)
Below what haemoglobin concentration would an adult be classified as anaemic?
Men: below 135g/L
Women: below 115g/L
What can anaemia be caused by?
- Reduced red blood cell mass
- Changes in plasma volumes
What can lead to changes in plasma volume?
- Dehydration
- Pregnancy
What are some of the symptoms of anaemia?
- Fatigue, breathlessness
- Angina
- Intermittent claudication
- Palpations
When can anaemia be asymptomatic?
When it develops slowly
How can we investigate anaemia?
Look at the
- Peripheral blood
- Blood film
- Bone marrow
- Haematinics
- Iron status markers
How do we use the peripheral blood to investigate anaemia
We can use:
- Red cell indices (Hb, MVC)
- White blood cell count
- Platelet count
- Reticulocyte count
What are haematincs
A nutrient required for haematopoesis e.g. Fe, B12, folate
Name the three nutrients haemantics usually refers to
- Iron (Fe)
- B12
- Folate
How do we classify anaemia ?
- By red cell size or volume (MCV)
- Underlying aetiology
What does MCV stand for
Mean corpuscular value
Name the different classifications of anaemia in regards to red cell size/ volume
- Microcytic anaemia
- Macrocytic anaemia
- Normocyctic anaemia
What is microcytic anaemia ?
Anaemia where the red blood cells are small
MCV is below 80
What is macrocyclic anaemia?
Anaemia where the red blood cells are large
MCV is greater than 96
What are the units for MCV?
Femtoliters
What is normocytic anaemia?
Anaemia where the red blood cells are normal sized
MCV is between 80-96
Name the different classifications of anaemia in regards to the underlying aetiology
Impaired production of red cells
- Haematinic deficiency (e.g. Fe, B12, folate) - most common
Increased loss of red cells
- e.g. haemolysis
What is an Haematinic deficiency?
Impaired production of red blood cells due to a deficiency in:
Fe
B12
Folate
most common
What is Haemolysis?
when blood breaks down abnormally
What happens if the Fe store balance in the body is disturbed
- impairs the absorption capacity
- increases the excretion
- makes you vulnerable to Fe deficiency
what is hypochromic
small pale cells
MCH <27
MCH= Mean corpusucalr haemaglobin
If a patient comes in with microytic anaemia what diagnosis might you reach?
- Iron deficiency
- Thalassaemia
- Anaemia of chronic disease
- Sideroblastic anaemia
If a patient comes in with macrocytic anaemia and large bone marrow what diagnosis might you reach?
Vitamin B12 or folate deficiency
If a patient comes in with macrocytic anaemia and normal bone marrow what diagnosis might you reach?
- Alcohol reticulocytes
- Liver disease
- hypothyroidism
- drug therapy
If a patient comes in with normocytic anaemia what diagnosis might you reach?
- Acute blood loss
- Anaemia of chronic disease
- Chronic kidney disease
- Autoimmune rheumatic disease
- Marrow infiltration fibrosis
- Endocrine disease
- Haemolytic anaemia
Why is iron important in the body?
Iron is required for Hb synthesis
What is a normal cell sized mcv?
80-96
Name the most common type of anaemia
Iron deficiency anaemia
What causes iron deficiency anaemia
- Blood loss
- Increased demand eg pregnancy, growth
- Decreased absorption (due to surgery)
- Poor dietary intake
How can we investigate iron deficiency anaemia?
Look at:
- Blood count
- Blood film
- Iron status
What do we expect to see in the blood count in a patient with iron deficiency anaemia
Microcytic hypochromic cells
What does hypo chromic mean when describing cells?
Pale cells
What do we expect to see in the blood film in a patient with iron deficiency anaemia
- Poikilocytosis (variation in shape)
- Anisocytosis (variation in size)
Which proteins do we look for when looking at the iron status of a patient?
Ferritin and transferrin