Blood Diseases - 1 Flashcards
What are the functions of blood?
- transport of nutrients
- removal of waste
- transport host defences
- ability to carry nutrients/waste/defences
- ability to self repair
What are the components of blood?
plasma
RBCs
WBCs
platelets
What are the major types of plasma proteins and what are their functions?
Albumin (osmotic pressure)
Globulins (antibodies, transport proteins)
Fibrinogens (blood clotting)
Other (various roles)
What are the abbreviations used in medicine?
- FBC - Full Blood Count
– Includes ALL of the values below - RBC - red blood cells
– Sometimes referred to as the RCC - red cell count - WCC - white cell count
- PLT - Platelets
- HCT - Haematocrit
- MCV - Mean Cell Volume
What is low Hb called?
anaemia
What is low WCC called?
leukopenia
What is low platelets called called?
thrombocytopenia
What is it called when all cells are reduced in the blood?
pancytopenia
What does one decreased change in blood count mean?
reactive change to the environment
What do multiple decreased changes in blood count mean?
bone marrow failure
What is raised Hb called?
polycythaemia
What is raised WCC called?
leukocytosis
What is raised platelets called?
thrombocythaemia / thrombocytosis
What does one increased change in blood count mean?
reactive or pre-neoplastic
What do multiple increased changes in blood count mean?
pre-neoplastic (myelodysplasia)
What is leukaemia?
neoplastic blood malignancy
proliferation of white cells
Usually disseminated
What is lymphoma?
neoplastic blood malignancy
proliferation of white cells
a solid tumour
What lineage is the origin of all leukocytes excluding lymphocytes?
myeloid stem cells
What lineage is the origin of lymphocytes?
lymphoid stem stells
Why is awareness of linage important?
cancers derived from different lineages behave differently
What is important to note about blood cancers?
- Any haematological cell line can turn neoplastic at a number of stages
- The earlier in the cell line this occurs the more potentially aggressive the malignancy
What are the lymphoid blood cancers? acute/chronic
Acute lymphoblastic leukaemia
Chronic lymphocytic leukaemia
Hodgkin lymphoma
Non-Hodgkin Lymphoma
Multiple myeloma
What are the myeloid blood cancers? acute/chronic
Acute myeloid leukaemia
Chronic myeloid leukaemia
Myeloproliferative disorders
What is porphyria?
abnormality of haem metabolism
What are the main groups of porphyria?
– Hepatic porphyrias
– Erythropoietic porphyrias
What is the dentally clinically relevant porphyrias type?
- Acute intermittent (AIP)
– Triggered by medicines including LA
What are the clinical effects of porphyria?
- Photosensitive rash (at any time)
- Neuropsychiatric disturbance in acute attacks
- Hypertension & tachycardia
may be fatal
What are the two reasons a blood transfusion may occur?
o Where one or more components of the blood has to be replaced quickly
- Red cells, platelets, Clotting factors (fresh frozen plasma)
o Where the bone marrow cannot produce blood cells
- Red cells, platelets
When would the whole blood be replaced?
when patient is losing blood volume very quickly
What is the ABO system?
- A: Red blood cells have A antigens.
- B: Red blood cells have B antigens.
- AB: Red blood cells have both A and B antigens.
- O: Red blood cells have neither A nor B antigens.
What is the D system?
the rhesus factor
can be + or -
important with maternal compatibility
What may be detected at the cross matching stage?
other cell surface antigens that are irregular
When should a blood transfusion be given?
- Blood loss
- Specific production problems with -
- RBC, Platelets
- Plasma proteins
- clotting factors, albumin, gamma globulins
What can happen during transfusions?
- Transfusion reactions
- Transmission of infection – not yet detected types
What are surface antigens made off?
combination of different chain sugars
What will happen in cross-matching testing if the blood has antibodies for the transfused blood?
agglutination
What are tranfusion complications?
- Incompatible blood -RBC lysis
-Fever, jaundice, death! - Fluid overload - Heart failure
- Transmission of infection
What is anemia?
- Anaemia is a reduction in HAEMOGLOBIN in the blood from the NORMAL values for that population
What are the two ways anemia can arise?
- Haemoglobin issues can be from an inability to make the HAEM (usually iron deficiency) or inability to make the correct GLOBIN chains – can be Thalassemia, Sickle Cell or other ‘haemoglobinopathies’
What can the size of the red blood cells indicate?
the size of the red blood cells (MCV) can give a clue as to the CAUSE of the anaemia
What does anaemia have nothing to do with?
Anaemia is nothing to do with the numbers of red blood cells – anaemia can happen with too many OR to few red cells
What are the problem anemia causes?
o reduced PRODUCTION
o increased LOSSES
o increased DEMAND
Why would there be reduced RBCs?
marrow failure
Why would there be reduced Hb?
- deficiency states - Fe, Folate, Vit B12
- abnormal globin chains
oThalassaemia
oSickle Cell - chronic inflammatory disease
What is aplastic marrow?
bone marrow cannot make enough RBCs resulting in aplastic anaemia
What are haematinics?
things used to make the red blood cells
What are the 3 haematinic deficiencies?
- Iron
- Vitamin B12
- Folic Acid (folate)
What are the sources of iron?
meat
green leafy veg
iron tablets
How is heme iron absorbed?
transported directly through intestinal cell walls in heme transporters
How is non-heme (Fe3+) iron absorbed?
cannot be absorbed and requires conversion to Fe2+ by stomach acid to be transported through intestinal cell wall
What are both types of iron stored as in the intestine?
ferritin
What are diseases reducing iron absorption?
- Achlorhydria - Lack of stomach acid no conversion of non-haem iron
may be Drug induced (Proton Pump Inhibitors) (lansoprazole, omeprazole) - Coeliac Disease
What are vitamin B12 sources?
Milk and diary
Eggs
Meat
Fish
Poultry
How are vitamin B12 supplements given?
injections
oral
Diseases that affect folic acid absorption also affect…
iron absorption
What are the reasons for vitamin B12 deficiency?
- Lack of intake – strict vegans
- Lack of intrinsic factor
- Autoimmune stomach disease – Pernicious anaemia
- Gastric disease
- Disease of terminal Ilium
- Crohn’s disease
What are folic acid sources?
leafy green veg
What are the reasons for folic acid deficiency?
- Lack of intake
- Peculiar diet habits
- Absorption failure
- Jejunal disease – coeliac disease
- Usually seen co-deficient with iron
What can folic acid deficiency lead to in fetal life?
neural tube defects
- spina bifida
How can haematinic deficiencies be recognised?
blood tests
What are b globin chains better at?
better at removing oxygen from maternal circulation for babies needs
What is thalassaemia?
normal haem production Genetic mutation of globin chains
Alpha chains (alpha thalassaemia) in Asians
Beta chains (beta thalassaemia) in Mediterraneans
What are the clinical effects of thalassaemia?
Chronic anaemia
Marrow hyperplasia (skeletal deformities)
Splenomegaly
Cirrhosis
Gallstones
What is the management of thalassamia?
blood transfusions
What is important to prevent during blood transfusions as treatment in thalassemia in regards to the liver?
prevent iron overload leading to cirrhosis as there is normal haem production
What is sickle cell anaemia?
Abnormal B Globin chains
* Change shape in low oxygen environments
* Prevent RBC from passing through the capillaries
* Tissue ischaemia – pain and necrosis
* Heterozygous (sickle cell trait)
* Homozygous (sickle cell disease)
