Anaemia Flashcards
Define Anaemia
Reduced levels of haemoglobin
How do you treat Iron-deficiency anaemia
Usually, oral iron
Blood Transfusion
In pregnancy, Oral Iron + folic acid
Megaloblastic anaemia
Abnormal RBC maturation due to defective DNA synthesis, out of step with cytoplasmic development: bone marrow contains megaloblasts
Macrocytic
What are the RBCs like in Megaloblastic Anaemia + why?
Macrocytic - RBCs are larger than normal volume
This is due to Vit.B12 / Folate deficiency
- Increased incidence in alcohol abuse
Symptoms of Megaloblastic anaemia
Anaemia + Jaundice
How is Jaundice caused in megaloblastic anaemia?
Excess breakdown of Hb due to increased ineffective erythropoiesis
B12
Co-factor for purine + pyrimidine synthesis
What is needed to absorb Vit.B12?
Intrinsic factor - secreted by stomach to help absorb B12
When is intrinsic factor absent?
After Gastrectomy
What is folic acid essential for?
Thymidylate synthesis
When is folic acid used + where is it found?
In pregnancy + in most foods
Function of Methotrexate + how to treat it?
Inhibits dihydrofolate reductase
Treat with Folinic acid
What is Pernicious anaemia + how do you treat it?
Lack of intrinsic factor for B12 absorption due to autoimmune disease
Treat with Hydroxocobalamin IM
Crohn’s disease
Malabsorption of Vit B12/ Folate or Iron
Haemolytic Anaemia
Increased rate of RBC destruction
What is Spherocytosis
Under Haemolytic anaemia
Genetic
Abnormal reduction in the RBC membrane protein Spectrin - make cells fragile
How can you get Haemolytic anaemia?
Malaria
Haemolytic Transfusion reaction
Drug-induced
What are the symptoms of haemolytic anaemia?
Jaundice + Enlarged spleen
Folate deficiency can occur due to increased erythropoiesis
Sickle cell anaemia
Genetic - single nucleotide polymorphism (SNP)
Amino acid substitution - Convert Glutamic acid for Valine
Abnormal Hb - insoluble forms crystals at low O2 - RBC form sickle shapes and may block microcirculation.
Causes haemolytic anaemia
Aplastic anaemia
Insufficient production of RBCs, WBCs and platelets (pancytopenia) - although may just be RBCs (pure red cell aplasia)
What does aplastic anaemia cause?
Decreased resistance to infections, increased bleeding + tiredness
How can you acquire aplastic anaemia?
Viral, radiation, drugs
Insecticides, sulphonamides, chloraphenicol + cytotoxic (anti-cancer drugs)
How do you treat aplastic anaemia?
Bone marrow transplant (tissue match)
Immunosuppressant (prevent immune destruction of stem cells)
Colony - stimulating factor (increases WBC count)
Thalassemia
Genetic
Reduced rate of alpha + beta globin unit production
= production of abnormal RBC
Deletion of both alpha genes in Thalassemia leads to…
Death in uterus as Hb produced
Deletion of ONE alpha gene in Thalassemia leads to…
reduction of RBC volume + haematocrit
How do you determine anaemia?
Blood flow
Glossitis
Painful red tongue
Angular cheilitis
Fissures at corner of the mouth
Symptoms for anaemia
Lethargy (lack of energy)
Tachycardia (increased heart rate)
Shortness of breath
When Input is reduced, it is caused by…
Poor diet; removal of stomach
What is Polycythaemia
Increased Hb content + haematocrit
-Increased blood viscosity = poor tissue perfusion
Symptoms of Polycythaemia
Ruddy appearance
Headaches
Blurred vision
Hypertension
What causes the polycythaemia
Primary: bone marrow changes, stem cell defect
Secondary: increased erythropoietin - altitude, smoking, renal carcinoma
Primary treatment of Polycythaemia
Venesection, radioactive phosphorus, cytotoxic agents
Macrocytic
Larger RBCs
Microcytic
Smaller RBCs
