Blood conditions Flashcards
How do you categorise anaemia
By mean cell volume and by mechanism
What are the different types of anaemia?
Microcytic
Normocytic
Macrocytic
Name causes of microcytic anaemia
IRON DEFICIENCY
Thalassaemia
Anaemia of chronic disease
Sideroblastic anaemia (hypochromic)
Name causes of normocytic anaemia
Acute bleeds Haemolyitic Anaemia of chronic disease Myelophythisic Aplastic
What is myelophthisic anaemia?
Anaemia caused by bone marrow being displaced by due to cancer, osteosclerosis or TB.
What is aplastic anaemia?
Where bone marrow dies.
Causes of macrocytic anaemia.
B12 and folate deficiency leads to megaloblastic anaemia
Sometimes haemolysis can look megaloblastic due to the reticulocytes present.
What is pancytopenia?
Decreased RBCs, WBCs and platelets.
Basic clinical features of anaemia
Tiredness and shortness of breath.
Causes of just splenomegaly with anaemia
Autoimmune haemolytic anaemia, cancer and hereditary spherocytosis.
Causes of hepatosplenomegaly with anaemia
Malaria and thalassaemia (due to extramedullary haematopoeisis.
Causes of jaundice with anaemia
Pre-hepatic: haemolytic anaemia and B12 deficiency.
How is B12 absorbed?
It binds intrinsic factor in the stomach and is absorbed in the terminal ileum.
Causes of B12 deficiency
Coeliac disease, IBD and resection.
Gastrectomy.
Autoimmune
Which anaemias give you haemoglobinuria?
The ones involving intravascular haemolysis.
Which anaemia will give a high unconjugated LFT and a low haptoglobin?
Hemolytic anaemia.
What investigations would you do for anaemia?
RBC, LFTs and blood film,
Iron, folate, B12, and ferritin.
Direct Coombs test.
Bone marrow biopsy or endoscopy.
What are the blood results from an acute bleed?
Increased urea, but less increased creatinine so the urea:creatinine ratio increases.
Also from eating meat and pre-renal failure.
What is a FAST scan?
A US scan of the following regions: perisplenic, perihepatic, pelvis and pericardiac.
List causes of haemolytic anaemias.
Malaria, autoimmune haemolytic anaemias, mechanical heart valve, spherocytosis, paroxysmal nocturnal haemoglobinuria, glucose-6-phosphate dehydrogenase
Causes of intravascular haemolysis
Paroxysmal nocturnal haemoglobinuria
Mech. heart valve
DIC, TTP, HUS, microangiopathic haemolysis.
Types of autoimmune haemolytic anaemias
Warm and cold.
What is the aetiology of warm haemolytic anaemia?
IgG and IgA bind RBCs at 37 degress leading to complement and phagocytosis
What is the aetiology of cold haemolytic anaemia?
IgM binds in the peripheries at 30 degrees, but doesn’t bind well centrally. When it binds in the peripheries, complement binds, but doesn’t form MAC, leading to opsonisation and uptake in the spleen.
What is hereditary spherocytosis
An inherited disorder in which mutation in the cytoskeleton leads to spherical RBCs and splenic haemolysis.
Types of haemoglobinopathy
Sickle cell anaemia
Thalassaemia
What happens in sickle cell anaemia?
RBCs sickle reversibly at low O2 due to polymerisation of Hb.
Complications of sickling in sickle cell anaemia.
Anaemia
Occlusion esp acute chest syndrome when pulmonary vessels occlude.
Increased osteomyelitis as a result of salmonella infections.
Increased gram +ive infections due to autosplenectomy.
Causes of anaemia due to decreased erythropoeisis
Myelophthisic, aplastic, megaloblastic.
Chronic disease
Iron def.
Kidney disease.
Chronic diseases leading to anaemia
Ca, TB, autoimmune
Signs of B12 def neuropathy
UMN, LM, sensory and dementia symptoms.
Ways in which people lose fluid
Diarrhoea and vomiting, fevers, bleeding, drains, fistulas, stomata, 3rd space losses.