Peripheral Blood Smear (PBS)
General · Blood
Available at 0 labs
No lab currently offers this test.
About this test
What is Peripheral Blood Smear (PBS)?
Peripheral Blood Smear is a microscopic examination of a thin layer of blood spread on a slide. It allows a laboratory technician to see the size, shape, and color of blood cells and to look for abnormal cells.
Key Parameters
| Parameter | What it shows |
|---|---|
| Red blood cell (RBC) morphology | Anemia types, iron deficiency, hemolysis |
| White blood cell (WBC) count & differential | Infections, leukemias, immune disorders |
| Platelet appearance | Thrombocytopenia, platelet disorders |
| Presence of abnormal cells | Malignancies, parasitic infections |
Why is it done?
- Routine check‑up or part of a complete blood count (CBC) panel.
- Evaluation of unexplained fever, fatigue, bruising, or infections.
- Monitoring patients on chemotherapy or with known blood disorders.
Early Detection
It can help identify signs of anemia, infections, leukemia, or parasitic infections, but it does not diagnose a disease on its own. A doctor interprets the smear along with symptoms, history, and other tests.
What abnormal results may mean
- Low RBC count or abnormal shape may indicate iron deficiency, vitamin B12 deficiency, or hemolytic anemia.
- High WBC count or abnormal WBC morphology may suggest infection, inflammation, or leukemia.
- Abnormal platelets can point to bleeding disorders or bone marrow problems.
Many factors—hydration, recent meals, medications—can affect the appearance of cells.
Who should consider this test?
- Anyone with unexplained anemia, fever, or bleeding.
- Patients undergoing chemotherapy or on immunosuppressive therapy.
- Individuals with a family history of blood disorders.
In short: PBS is a quick, low‑cost way to spot red‑flag changes in blood cells that may need further investigation.
Used for detecting / monitoring
Before your test
- Fasting: No fasting required for PBS.
- If combined with fasting tests: Follow the longest fasting period required by any test in the panel.
- Procedure: A small vein (usually in the arm) is cleaned, a needle inserted, and a few drops of blood are drawn. The blood is then spread thinly on a slide and stained.
- Time: The whole process takes about 5–10 minutes.
- Comfort: A brief needle prick; most people feel only a quick pinch.
- Precautions: Stay hydrated, avoid alcohol or strenuous exercise 24 h before if you are also doing other tests that require it.
- Note: Confirm any specific preparation with your doctor or the lab. This information is educational and not a substitute for professional medical advice.
Sample type: Blood
Report parameter guide
RBC count
Number of red blood cells per unit volume of blood
Low: Can indicate anemia, blood loss, or nutritional deficiencies
High: Can indicate dehydration, polycythemia, or high red cell production
WBC count
Number of white blood cells per unit volume of blood
Low: Can indicate immunosuppression, bone marrow suppression, or severe infection
High: Can indicate infection, inflammation, leukemia, or stress response
Platelet count
Number of platelets per unit volume of blood
Low: Can indicate thrombocytopenia, bone marrow disorders, or increased platelet destruction
High: Can indicate thrombocytosis, inflammation, iron deficiency, or bone marrow stimulation