Laboratory test
Blood count
Other names and abbreviations: blood count, CBC, WBC, RBC, HGB, PLT
A basic blood test: red cells, white cells and platelets. Helps detect anaemia, infections and clotting disorders.
A blood count is one of the most frequently ordered tests. It shows the number and appearance of red blood cells (which carry oxygen), white blood cells (responsible for immunity) and platelets (involved in clotting). A single result slightly outside the range often doesn't matter – the doctor assesses it together with your symptoms.
Typical ranges in adults
| Parameter | Typical range | What a deviation may mean |
|---|---|---|
| White blood cells (WBC) | 4–10 thousand/µl | high: infection, inflammation; low: e.g. viral infections, medicines |
| Red blood cells (RBC) | W: 3.8–5.2 · M: 4.2–5.8 million/µl | low: anaemia |
| Haemoglobin (HGB) | W: 12–16 · M: 13.5–17.5 g/dl | low: anaemia |
| Haematocrit (HCT) | K: 36–46% · M: 40–52% | high: e.g. dehydration |
| MCV | 80–100 fl | low: often iron deficiency; high: e.g. B12 deficiency |
| Platelets (PLT) | 150–400 thousand/µl | low: risk of bleeding; high: e.g. inflammation |
The ranges are approximate and differ between laboratories; they also depend on age, sex and pregnancy. A result outside the range doesn't always mean illness – discuss it with a doctor.
When it is done
In preventive check-ups once a year, with weakness, paleness, recurrent infections, bruising, before procedures.
How to prepare
Usually no special preparation is needed. In the morning before the blood draw, it's best not to eat a heavy breakfast – ask at reception.
