Anaemia, Haemolysis And Haematinic Deficiency Flashcards
What is in the blood
Plasma
Platelets
White cell
Red cells
What is the normal life span of a rbc
120 days
What are the causes of microcytic anaemia
Iron deficiency anaemia
Thalassemia and thalassemia trait
What are the causes of normocytic anaemia
Anaemia of chronic disease
Acute blood loss
Bone marrow failure e.g aplastic anaemia
Mixed Haematinic deficiency
What are the causes of macrocytic anaemia
Vitamin b12 and folate deficiency Alcoholism Liver disease Haemolytic anemia Hypothyroidism Drugs eg anti-epileptics
What are the categories of causes of anaemia
Acquired
Congenital
What are the congenital causes of anaemia
Membrane defect: hereditary spherocytosis, hereditary elliptocytossi
Haemoglobin defect: thalassemia and sickle cell anaemia
Enyzme defect: G6PD deficiency and pyruvate kinase deficiency
What are the acquried causes of anaemia
Deficiences: vitamin b12, folate, iron
Bone marrow pathology: aplastic anaemia, mylodysplasia, myeloma
Diplacement in the bone marrow: leukemia, other cancer
Chronic disease: renal failure (unable to make erythropoietin)
Haemolysis: immune and non immune
What happens in bleeding?
- Acute blood loss there is lack of RBC and plasma as they are bleedng whole blood
- Hb concentration remains the same
- Plasma volume expands to maintain the blood pressure and due to this there is a fall in hb concentration as the RBC become diluted in a bigger volume
- If you keep bleeding i.e chronically, bone marrow will make more RB and will use the iron stores
- Ferritin will drop
- As long as there is enough iron hb levels will be normal
- If chronic you will deplete the iron stores eventually so ferritin levels will drop
- This results in iron deficiency anaemia
Describe how iron is metabolised
- In the gut lumen Haem bound iron and non haem iron are absorbed differently
- No haem bound iron will be reduced from fe2+ to fe3+ for it to come into the enterocytes
- When it becomes into the enterocyte it is stored as ferritin
- Or the iron can be transported into the basolateral membrane i,.e blood by ferroportin
- Feroportin is controled by hepcidin
- Hepcidin is produced by the liver
- In iron deficiency there will not be hepcidin so the flow of iron will be free out from the enterocyte
- If there is anaemia of chronic disease, hepcicin levels will go up and block iron from getting into the body i.e there is iron but it cant go to where it should due to hepcidin
What are the symptoms and signs of iron deficiency anaemia
Koilonchyia Restless leg Pica Breathelessness Fatigue Palpitatons Tinnitus Pallor Tachycardia Flow murmur
What are the causes of iron deficiency
Poor intake from diet
Poor absorption: coeliac disease, crohns disease
Preganct: due to increased body requirements
Iron loss i.e bleeding due to: gi malignanct, ulcer, gastricits, menorrhagia, urinary, angiodysplasia
What will an iron deficiency anaemia show on a blood film
Microcytic hypochromic anaemia
What happens ot the total iron binding capacity in iron deficiency anaemia
High becuase it wants the body to pick up iron and take it to where it should be
What is the ferritin levels in anaemia of chronic disease
Normal
What is the management of iron deficiency anaemia
- Find the underlying cause
3. Treat the iron deficiency by iron tablets or iv iron
What are the causes of folate deficiency
- Low intake
- Impaired absorption: duodenum pathology e.g coeliac or crohsn disease, drugs
- Increased requirement: pregnancy, haemolysis, inflammation
- Increased loss of folate: people on dialysis, durgs dihydrofolate reductase inhibitors
What are the signs and symptoms of folate and b12 deficiency anemia
Jaundice Glossitis Mild fever Skin hyperpigmentation Infection and bleeding Infertility Neural tube defect
In the peripheral bloood what are the featues of b12 and folate deficiency
Hyperpigmented neutrophils
How can we measure folate levels in the blood
Elisa technique
Serum
Red cells- low in b12 deficiency
What are the 2 ways b12 can be absorbed
- Passively in the duodenum and ileum
2. actively by binding to intrinsic factor made from the stomach which then is absorbed in the ileum
What are the neurological featues of b12 deficiency
Muscle weakness
Parathesia
Difficulty walking
Confusion, slowlness
What are the causes of b12 deficiency
Poor intake
Malabsorption: gastric, ileum, drugs e,g metformin
Loss: nitrous oxide makes b12 inactive
Apparent deficiency: pregnancy
How can we measure b12 levels in the body
B12 assay
Schilling test
What is pernicious anaemia
An autoimmune disorder that causes destruction of intrinsic factor due to antibodies against parietal cells
How do we diagnose pernicious anaemia
Measure intrinsic factor antibodies
How do we replaces b12
1mg hydroxycarbalamin intrmuscular injection
What test makes us think about immune causes of hamolytic anaemia
DAT (coombs test) that is positive
What are the 2 types of autoimmune hameolytic anaemia
Warm- igg
Cold- igm
What is the treatment of warm autoimmune haemolytic anaemia
Streoids
Splenectomy
Rituximab
What is cold autoimmune haemolytic anaemia associated with
Ebv
Mycoplasma pneumonia
Lymphoma
What is the treatment of cold autoimmune haemolytic anaemia
Transfuse with blood warmer
Treat underyling infection
- doest not respond to steroids
