Anaemia- presentation, diagnosis and treatment Flashcards
What are the symptoms of anaemia?
- Fatigue
- Symptoms relating to reduced O2 delivery
- Short of breath
- Muscle pain exertion
- dizzy
- angina
What are the clinical signs of anaemia?
- Pallor in skin and conjunctiva
- Tachycardia
- Rapid breathing
- Peripheral oedema if severe anaemia
- Signs relating to cause of anaemia
How can anaemia classifications?
- Under- production or increased loss RBC
- Congenital or acquired
- Acute or chronic
- By mean cell volume
Describe Microcytic anaemia
- Small
- MCV 60-80 fl
- e.g. iron deficiency; thalassemia
Describe Normocytic anaemia
- MCV 80-100fl
- e.g. recent blood loss, anaemia of chronic disease, renal impairment
Describe macrocytic anaemia
- MCV 100-130 fl
- megablastic anaemia - B12/ folate deficiency
What is the most common cause of anaemia?
Iron deficiency
How does iron deficiency initially present?
low MCV, low Hb, low ferritin, low transferrin saturation, and sometimes high platelets (if bleeding is ongoing).
Causes of iron deficiency
-Reduced intake
-Blood loss eg
-Menstrual
-GI tract haematemesis or melaena eg peptic ulcer/cancer/angiodysplasia/hookworm (image)
-Malabsorption- coeliac disease
-Increased need eg growth spurt/pregnancy
What are the clinical features of iron deficiency?
- Pale
- Tachycardia
- Koilonychia
- Hair loss
- Pica (especially in children)
- Glossitis/angular stomatitis
-Features relating to the cause eg wt loss/abdo pain/bowel change/heavy periods
How to investigate iron deficiency
- history
- confirm iron deficiency by low ferritin and typical full blood count
- Screen for coeliac disease
- Upper and lower endoscopy (higher threshold in pre- mennopausal women)
How can iron deficiency be treated orally?
replacement with sufficient iron for long enough period eg ferrous sulphate 200mg once per day (recent change in guidelines)- 65mg elemental iron per dose
What are the side effects for oral replacement of iron?
nausea/abdo pain/constipation-
Describe parenteral iron treatment?
- IV
- Ferric carboyxmaltose - ferinject - over 15-30min often needs 2 doses
- Iron dextran - cosmofer over 4-6 hours after
What are the side effects of the side effects of IV iron preparations?
flu like symptoms and a small risk of hypersensitivity reaction or anaphylaxis
What type of anaemia does B12 deficeincy fall under?
- Macrocytic anaemia
- MCV - 100 -120
What are the effects of B12 deficiency?
- Pancytopenia
- Bilirubin and LDH levels raised ( ineffective erythropoiesis)
- Peripheral neuropathy - demyelination and posterior column damage
When is the B12 reference range lower?
In pregnancy
oral contraceptive
on metformin
What is pernicious anaemia and how does it lead to B12 deficiency?
Pernicious anaemia- gastric atrophy and auto antibodies to parietal cells and intrinsic factor preventing absorption of B12
How can Hydroxocobalamin be used to treat B12 deficiency?
1mg intra-muscular alternate days for 5 doses then 3 monthly if confirmed ongoing need eg pernicious anaemia
How can Cyanocobalamin be used to treat B12 deficiency?
orally (50-150 micrograms per day) used as supplement eg on vegan diet
How does folate deficiency present?
Blood count and film appearance same as B12 deficiency
How can folate deficiency be treated?
Replacement with oral folic acid 5mg per day
Pre-conception folic acid (0.4mg/day) reduces neural tube defects.
Describe acute blood loss
Hb immediately after blood loss will be normal
Drop after fluid replacement or re-distribution
Each 500ml loss gives approx drop of Hb by 10-15 g/l
Reticulocyte response within hours
May need blood transfusion to replace loss eg trauma/GI bleed/around delivery
