Blood (Cells, Coagulation & Cancer Of) Flashcards
What is anaemia?
A decrease in the number/concentration of RBCs or a decrease in the number/concentration of Hb.
What stimulates erythropoietin production?
The decreased oxygenation of the blood (not the number or concentration or RBCs).
Hence Ps may have high RBC numbers if they have chronic hypoxia from living at altitude.
What is aplastic anemia?
Suppression of the bone marrow (due to drugs / radiation).
= All blood cells decrease in number = pancytopenia
What type of anaemia can present from low iron?
Iron deficiency anaemia
What is iron transported by and stored by?
Transported by protein - transferrin
Stored by protein - ferritin
What type of anaemia can present from low transferrin levels?
Iron deficiency anaemia
What vitamins are important for the synthesis of DNA?
B12 and folic acid
How does low B12 and FA affect RBCs?
Can cause large, fragile, short-lived RBCS = MEGALOBLASTIC ANAEMIA
What is produced in the gut that is needed for transport of B12?
Which cells produce this?
What does it do?
Intrinsic factor
Produced by parietal cells in gastric mucosa
Protects B12 from digestion and transports it across intestinal mucosal membranes.
What type of anaemia is caused by low levels of intrinsic factor?
Megaloblastic anaemia
Which two diseases cause defects in the structure of haemoglobin?
Sickle cell anaemia
Thalassemia
When do Ps have sickle cell crisis if they have the heterozygous allele of the gene?
During times of marked hypoxia
What does thalassemia do to RBCS?
Causes a defect in the quantities of PP chains that are part of the HB molecule.
Means that Ps carry too little O2 - can cause anaemia symptoms.
Are two types - α and β. β is the more severe.
Name 3 types of anaemia due to defects in the red cell membrane.
Hereditary spherocytosis
Hereditary elliptocytosis
Paroxysmal nocturnal haemoglobinuria
