What are Platelets?

Platelets (thrombocytes) are small blood cell fragments that help stop bleeding by forming clots. They're produced in the bone marrow and circulate in the bloodstream.

Why is it Important?

Platelet count is used to:

Assess bleeding or clotting risk
Diagnose bone marrow disorders
Monitor chemotherapy or radiation effects
Guide surgical decisions
Evaluate bleeding disorders (ITP, hemophilia)

Normal Ranges

Classification	Range	Unit
Normal	150 – 400	×10³/µL
Mild Thrombocytopenia	100 – 150	×10³/µL
Moderate Thrombocytopenia	50 – 100	×10³/µL
Severe Thrombocytopenia	< 50	×10³/µL
Thrombocytosis	> 450	×10³/µL

What Do Abnormal Results Mean?

Low Platelets (Thrombocytopenia)

Common causes include:

Immune thrombocytopenia (ITP)
Medications (heparin, chemotherapy)
Viral infections (dengue, HIV)
Bone marrow disorders (leukemia, aplastic anemia)
Enlarged spleen (sequestration)
Pregnancy (gestational thrombocytopenia)
Alcohol abuse
Vitamin B12 or folate deficiency

High Platelets (Thrombocytosis)

Common causes include:

Reactive (secondary): Infection, inflammation, iron deficiency, cancer, post-surgery
Primary: Essential thrombocythemia, polycythemia vera, chronic myeloid leukemia
Splenectomy (removal of spleen)

Bleeding Risk by Platelet Count

> 100,000: Generally safe for surgery
50,000 – 100,000: Minor bleeding with trauma
20,000 – 50,000: Bleeding with minor trauma, bruising
< 20,000: Spontaneous bleeding, petechiae (tiny red spots)
< 10,000: High risk of serious bleeding, requires urgent treatment

When Should You Get Tested?

Platelet count is part of routine complete blood count (CBC). Your doctor may order it if you have unexplained bruising, bleeding, petechiae, or before surgery.