Introduction To Anaemia Flashcards
What is anaemia?
A haemoglobin concentration lower than the normal range.
What are some signs and symptoms of anaemia?
Symptoms: shortness of breath, palpitations, claudication. Signs: Pallor, tachycardia, hypotension.
What are specific signs associated with anaemia?
Koilonychia (spoon shaped nails)- iron deficiency. Angular stomatitis- iron deficiency. Glossitis (inflammation of tongue)- vitamin B12 deficiency.
Why might anaemia develop?
Bone marrow- reduced erythropoiesis, abnormal haem synthesis, abnormal globin chain synthesis. Peripheral RBCs- abnormal structure, mechanical damage, abnormal metabolism. Finally, excessive bleeding and increased removal.
Describe inherited anaemia.
Mutations in genes coding for proteins involved in interactions between plasma membrane and cytoskeleton. Causes cells to become less flexible and easily damaged. These are removed quickly by RES.
Types of acquired damage.
Mechanical stress- fragments resulting from this are called schistocytes. Heat damage from severe burns and osmotic damage.
How do you evaluate anaemia?
2 key features: The rbc size, the presence or absence of reticulocytes.
What is macrocytic anaemia?
Anaemia where the MCV is greater than normal
Types of macrocytic anaemia.
Megaloblastic anaemias- cell division delayed and erythroblastosis form megaloblasts, e.g. vitamin B12/folate deficiency. Macronormoblastic erythropoiesis- normal development, erythroblasts are larger than normal, e.g. liver disease. ‘Stress’ erythropoiesis- high reticulocyte count, e.g. recovery from blood loss due to haemorrhage.
Causes/symptoms of folate deficiency.
Causes: dietary deficiency, increased requirements (pregnancy), disease of the duodenum and jejunum (Crohn’s), drugs which inhibit dihydrofolate reductase. Symptoms: those related to anaemia, diarrhoea, muscle weakness, reduced sense of taste.
What is vitamin B12?
A water soluble vitamin which is an essential cofactor for DNA synthesis. It is required for normal erythropoiesis and is produced by bacteria. It is largely obtained from foods of animal origin, vegan diets may require a B12 supplement.
Causes and symptoms of vitamin B12 deficiency.
Causes: dietary deficiency, disease of ilium (Crohn’s), lack of intrinsic factor. Symptoms: Like anaemia, diarrhoea, parasthesia.
Treatment of vitamin B12/folate deficiency.
Folate: oral folic acid. B12: for pernicious anaemia- hydroxycobalmine intramuscular for life, other causes- oral cyancobalamine.
