Anaemia Flashcards
What is anaemia
(3)
A decrease in the competence of blood to carry oxygen to tissues, thereby causing tissue hypoxia
It is not a disease but the expression of an underlying disorder or disease -> once anaemia is diagnosed the cause must be determined
Defined clinically when Hb concentration is below the accepted range
What group of individuals may have a high haemoglobin
Babies
What is the average haemoglobin for an adult female
140
What is the average haemoglobin for an adult male
155
List the signs of anaemia
(5)
Pallor
Tachycardia
Glossitis
Koilonychia
Dark urine
What is tachycardia
Pulse rate over 100 beats per minute
What is glossitis
Swollen and painful tongue due to vitamin B12 deficiency
What is koilonychia
Spoon nails -> seen in iron deficiency
What type of anaemia is dark urine seen in?
Haemolytic anaemia
What are the symptoms of anaemia
(6)
Decreased work capacity
Fatigue, lethargy
Weakness
Dizziness
Palpitations
Shortness of breath
What are the symptoms of severe anaemia
(7)
Jaundice
Splenomegaly
Hepatomegaly
Angina
Cardiac failure
Fever
Fainting
What is meant by “adaptations” to anaemia
(2)
A healthy person can lose up to 1 litre or 20% of blood and not have any symptoms except mild tachycardia during exercise
Therefore if you gradually develop a dietary anaemia your body will make adjustments for the anaemia -> body will get used to this e.g. in pregnant women -> they might not feel it until haemoglobin is very low
e.g. body might increase blood flow
How much blood can a person lose
Severe blood loss is considered between 1.5 and 2L (30-40% of blood) -> leads to circulatory collapse and shock
If 50% of blood is lost then death is imminent
Give some examples of how the body adapts to anaemia
Increase in oxygenated blood flow
Increase in oxygen utilisation by tissues
How does the body increase oxygenated blood flow
(4)
Increase cardiac rate
Increase cardiac output
Increase circulation rate
Preferential increase in blood flow to vital organs
How does the body increase oxygen utilisation by tissues
Increases 2,3-DPG in erythrocytes
2,3-DPG forces haemoglobin to release oxygen
Anaemia is classified by the causes, list these categories
(6)
Bone marrow
Problems with iron
Lack of vitamins
Anaemia associated with disease in other organs
Haemolysis
Anaemia arising from a gene mutation
What two things result in bone marrow caused anaemia
Suppression
Infiltration
What three things involving iron cause anaemia
Deficiency at the bone marrow
Excess absorption
Ineffective incorporation into haem
Anaemia can be associated with what organs
Liver
Kidney
Reproductive organs
Connective tissues
Thyroid
Anaemia can be caused by haemolysis under what conditions?
Due to antibiotics
Due to drugs
Due to infections
Anaemia can rise from what genetic mutations
Haemoglobinopathies
Membrane defects
Enzyme defects
In general what are the three causes of anaemia
Decreased production of red cells -> due to marrow failure
Increased destruction of rbcs -> haemolysis
Loss of red cells due to bleeding -> acute/chronic blood loss
What are the two ways to classify anaemias
On the basis of cause
On the basis of morphology
How are anaemias classified on the basis of morphology
(3)
Normocytic
Microcytic
Macrocytic
What information can you find from the full blood count
(9)
Amount of haemoglobin the the blood
Number of rbcs
% of rbcs as a proportion of the total blood volume (Haematocrit)
Average volume of rbcs (MCV)
Average concentration of Hb in the RBC (MCBH)
Average concentration of Hb in the RBC volume (MCHC)
Number of wbcs
% of the different types of WBCs
Number of platelets
What does MCV let us know?
If the rbcs are microcytic, normocytic or macrocytic
What are the causes of microcytic anaemia
(4)
Iron deficiency
Chronic disease (Renal Failure)
Haemoglobinopathies (Thalassemias)
Sideroblastic Anaemia
What can cause normocytic cells in anaemia
(5)
Acute bleeds
Chronic disease
Early iron deficiency anaemia
Bone marrow disorders
Haemolytic Anaemias
What can cause macrocytic rbcs in anaemia
(5)
Megaloblastic anaemias
Liver disease/alcohol
Metabolic disorders
Bone marrow disorders
Haemolytic anaemias
What does red cell distribution width measure
Anisocytosis
Anisocytosis is often seen in what types of anaemia
Thalassaemias and anaemia of chronic disorder
What does a patient with a low MCV and high RDW have
Iron deficiency anaemia
What does a normal RDW and a low MCV suggest
Thalassaemia or an anaemia of chronic disorder
What does a normal RDW and a low MCV suggest
Thalassaemia or an anaemia of chronic disorder
What does a normal RDW and a low MCV suggest
Thalassaemia or an anaemia of chronic disorder
What occurs in hypoproliferative bone marrow
(4)
Decreased reticulocytes
The bone marrow is unable to produce requisite number of RBCs
Lack of essential substances to make rbcs such as iron, B12 or folate
Lack of essential substance due to the invasion of the marrow by a disease process such as leukaemia or aplastic anaemia
What happens in hyperproliferative bone marrow
(4)
Increased reticulocytes
Cause of anaemia outside the marrow e.g. haemolytic anaemia, or haemorrhage
Decreased survival of the rbcs
Marrow normal and responds adequately by increasing the output
What is the % reticulocyte count
The total number of reticulocytes seen in 1000 red cells
What might increase % reticulocyte count
(2)
An increase in the number of reticulocytes in circulation
A decrease in the rbc count
What is the absolute reticulocyte count
(2)
A more accurate reticulocyte count used to diagnose anaemia
A more informative index of erythropoietic activity as it takes into account the red cell count
What is the equation for an absolute reticulocyte count
RBC x % retic count (50-100 x 10^9/L)
What happens to retic count and RDW in iron deficiency
Retic count often decreased
RDW may be high
What happens to retic count and RDW in thalassemia
Reticulocyte count often elevated
RDW may be normal
What happens to retic count and RDW in chronic disease
Retic count often decreased
RDW may be normal
What is anisocytosis
Different sizes of RBC
What is poikilocytosis
Different shapes of RBCs
Target cells are seen in what disorders
(5)
Iron deficiency
Liver disease
Thalassemia
HbC/D Disease
Post splenectomy
