CBL8 Anaemia Flashcards
Definition of anaemia
- a reduction in one or more of the major RBC components obtained in a full blood count’:
–RBC count
–Haemoglobin
–Haematocrit (ratio of RBCs to whole blood)
*may be due to either low red cells mass or increased plasma volume -for example in pregnancy
What is ‘low Hb’ in ranges for men and for women
Low Hb
- Men: <135 g/L
- Women: < 115 g/L
Symptoms of anaemia
- Fatigue
- Dyspnoea
- Faintness
- Palpitations
- Headache
- tinnitus
- Anorexia
- Angina
Signs of anaemia
- pallor (including conjunctival pallor)
- tachycardia
- flow murmurs (ejection-systolic loudest over apex)
- cardiac enlargement
*Heart failure may occur
What’s the most widely used method in identifying the cause of the anaemia?
The most widely used method utilises the Mean Corpuscular Volume (MCV) – the average volume of RBCs:
–Too small: microcytic
–Within normal limits: normocytic
–Too big: macrocytic
Is it reliable to rely only on MCV in identifying the cause of anaemia?
MCV is only a mean, and doesn’t tell you everything about the RBC characteristics
Common causes of microcytic anaemia
Microcytic anaemia:
- Iron deficiency
- thalassaemic syndromes
- sideroblastic anaemia
- anaemia of chronic disease
What’s the value of Hb to classify anaemia as microcytic?
This is when their mean cell Hb correlates with less than 72
Causes of normocytic anaemia
Normocytic anaemia:
- Acute blood loss
- Anaemia of chronic disease
- Bone marrow failure
- Renal failure
- Hypothyroidism
- Haemolysis
- Pregnancy
Causes of macrocytic anaemia
Macrocytic anaemia
- B12 or folate deficiency
- Alcohol excess/ Liver disease
- Reticulocytosis
- Cytotoxics (e.g. hydroxycarbamide)
- Myelodysplastic syndromes
- Marrow infiltration
- Hypothyroidism
- Antifolate drugs (e.g.phenytoin)
What is MCV?
Mean cell volume (MCV) = mean volume of red blood cells (RBC)
What is MCH?
Mean corpuscular haemoglobin (MCH) = mean Hb quantity within the blood cells
What is Hb?
Haemoglobin (Hb) = concentration of Hb within the blood
When is a blood transfusion needed?
The patient will not need blood transfusion unless:
- they are acutely bleeding and therefore will need some until their blood is up to 80g/L
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: iron deficiency anaemia
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: anaemia of chronic disease
What is ferritin?
Ferritin - blood cell protein that contains/ stores iron
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: chronic haemolysis
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: haemochromatosis
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: pregnancy
What are the plasma results for:
- iron 2. TIBC 3. ferritin
in: sideroblastic anaemia
Causes of iron deficiency anaemia
- Dietary: lack of red meat; beef and lamb are good sources and liver
- Chronic blood loss (menorrhagia, chronic GI blood loss)
- Decreased absorption (coeliac disease, atrophic gastritis, foods e.g. tea)
- Pregnancy
- Hookworm and schistosomiasis in the tropics that might cause GI loss -this is the leading cause worldwide
What ‘s sideroblastic anaemia? (simply what happens)
Sideroblastic anemia or sideroachrestic anemia is a form ofanemia in which the bone marrow produces ringed sideroblasts rather than healthy red blood cells (erythrocytes).
What result (on a blood test) would confirm IDA?
confirmed by reduced ferritin
Definition of iron deficiency anaemia
Anaemia in association with a low MCV and evidence of depleted iron stores such as:
- low ferritin
- increased TIBC (total iron binding capacity) *
*as less iron bound = more space available = increased
What type of anaemia iron deficiency anaemia is?
- IDA is a microcytic hypochromic anaemia
Signs of Iron Deficiency Anaemia
- Koilonychia
- Atrophic glossitis
- Angular cheliosis
- and rarely post-cricoid webs
A classic picture of iron deficiency anaemia (values)
–Hb 95 g/L (male normal 130-180)
–MCV 72fL(normal 80- 100)
–MCH 26 pg MCH (normal 27 - 32)