Platelet Count
- Platelets are component of blood whose function is to stop bleeding by clumping and clotting blood vessel injuries
- The platelet count is used to check the number of platelets that are in blood.
- This may be used to:
- monitor the effects of certain drugs known to affect platelets, such as:
- acetylsalicylic acid (aspirin),
- adenosine diphosphate receptor antagonists (clopidogrel and
prasugrel)
- diagnose or monitor diseases that affect the bone marrow.
- A normal platelet counts ranges from 150,000 - 450,000 platelets/µl of blood
- Low platelet count (less than 150,000 cells/µl) is called thrombocytopenia- Can be caused by:
a. Decreased production of platelets in the bone marrow,
e.g. in: - Cancer in the bone marrow, such as leukemia
- Cirrhosis (liver scarring)
- Vitamin B12 and Folate deficiency
b. Increased breakdown of platelets:
e.g. in: - Pregnancy. usually mild and improves soon after childbirth.
- Bacteremia
- Medications may confuse the immune system and causes it to
destroy platelets, such as:
- quinine (treat malaria)
- sulfa-containing antibiotics (trimethoprim-
sulfamethoxazole)
and – anticonvulsants (e.g. levetiracetam)
- High platelet count (More than 450,000 cells/µl) is called thrombocytosis
- Can be caused by:
- Bone marrow disease called polycythemia vera
- Medications: - Epinephrine
- Tretinoin
- Heparin sodium