Full Blood Counts

Question 1

What are the definitions of the following:
* MCV
* MCH
* MCHC

Answer 1

MCV = Average size of RBC
MCH = Amount of haemoglobin per RBC
MCHC = Average concentration of haemoglobin in a given volume of blood

Question 2

What are the names for a low, normal and high MVC

Answer 2

Low = Microcytic
Normal = Normocytic
High = Macrocytic

Question 3

What is polycythaemia?

Answer 3

Abnormally high haemoglobin concentration which can be due to an increase in the number of RBCs (Absoloute polycythaemia) or decrease in plasma (relative polycythaemia)

Question 4

What are some causes of primary/absoloute and secondary/relative polycythaemia

Answer 4

Primary - Myeloproliferative neoplasms.
Secondary - COPD, smoking, obstructive sleep apnoe, lung fibrosis, alcohol excess

Question 5

What are causes of a microcytic anaemia?

Answer 5

TAILS
-Thalassaemia
- Anaemia of chronic disease
- Iron def anaemia
- lead poisoning
- Sideroblastic anaemia

Question 6

What are the causes of a normocytic anaemia?

Answer 6

• Anaemia of chronic disease
• Acute blood loss
• Increased plasma volume (pregnancy)
• Haemoglobinopathies (thalassaemia)
• Aplastic anaemia
• Hypersplenism

Question 7

What are the causes of a macrocytic anaemia?

Answer 7

• B12/folate def
• Toxins eg, alcohol or chemo,
• Liver disease
• Pregnancy
• Myeloma
• Hypothyroidism

Question 8

What is haematocrit?

Answer 8

The percentage of blood sample made up of RBCs. Raised haematocrit can cause hyperviscosity syndrome

Question 9

What is the importance of a reticulocyte count?

Answer 9

Reticulocyte is an immature RBC. In anaemia if the reticulocyte count is low then it suggests bone marrow problem (could be due to deficiencies or primary bone marrow disease). If reticulocyte count is hgih then indicates body is compensating for blood loss or haemolysis

Question 10

What is the name for high/low white cell count and some causes

Answer 10

Leukocytosis - Reactive (infection), steroids (stress response or meds) or acute leukaemias, pregnancy
Leukopenia - infections, meds (immunosupressants), B12/folate def, autoimmune diseases, iron def, HIV

Question 11

What are causes of an isolated neutropenia

Answer 11

Infections, bone marrow failure (malignancy or infection), hypersplenism, Felty’s syndrome and SLE

Penia = low

Question 12

What is Agranulocytosis and some causes

Answer 12

Agranulocytosis - depletion of granular WCs eg, basophils, eosinophils, neutrophils.
Causes - carbamazepine, carbimazole and clozipine

Question 13

What are some common and less common causes of neutrophilia?

Answer 13

Common - Severe stress state (infection, surgery, necrosis, burns, haemorrhage) or any state of active inflammation (MI, disseminated malignancy)
Less common - Corticosteroid use, myeloproliferative diseases (polycythaemia vera, CML, essential thrombocytopenia)

Question 14

What are causes of lymphocytosis?

Answer 14

Viral infection, smoking, malignancy (leukaemia and some lymphoma), hyposplenism

Question 15

What are some causes of a lymphopenia

Answer 15

• Infection,
• Older age
• alcohol excess
• HIV
• Autoimmune disease

Question 16

What are some causes of eosinophilia

Answer 16

• Allergy/atopy
• Parasitic infection
• Autoimmune
• Medications
• Respiratory disease (asthma)

Question 17

What are some causes of basophilia

Answer 17

• Allergic reactions/atopy,
• Iron deficiency
• Chronic inflammation

Question 18

What are some causes of acute thrombocytopenia?

Low platelets

Answer 18

• Consumption
• Acute viral infection
• Medications
• DIC
• HIT
• ITP
• Pre-eclapsia

Question 19

What are some causes of chronic thrombocytopenia?

Low platelets

Answer 19

• Hypersplenism
• Cirrhosis
• Alcohol excess
• Medications
• ITP
• Autoimmune disease
• B12/folate/iron deficiency
• HIV
• Hepatitis

Question 20

What are some causes of thrombocytosis?

Answer 20

• Reactive - infection/inflammation
• Myeloproliferative,
• Iron deficiency
• Hyposplenism
• Underlying maligancy