Platelets in the Blood

A Simple Description: 

When considering the importance of platelets to the body it is first important to know what they do.  Platelets are the part of the blood that contribute the clotting factor.  When a blood vessel is damaged (cuts, scrapes or other reasons you might find yourself bleeding) the muscles in the walls of the vessel constrict and the platelets go to the site of the injury, stick together like glue and create the clot so the body can start the healing process. 

Without platelets (or with a low platelet count)  you could continue to bleed and the flow of blood just wouldn’t stop (called hemorrhaging); thus you could bleed to death even from a small cut.  People who have a chronic problem with low platelet counts are called hemophiliacs or bleeders.  They can die from a small cut.

What’s a good ratio of platelets in the blood? 

The normal volume of platelets in the blood ranges from 150,000 to 450,000 per microliter of blood.  Platelet count is low on birth, but increases to the adult level within the first three months of life.   Both men and women generally have a similar platelet count.  Doctors get the ratio information of platelets in your blood by having a CBC (complete blood count)  test run on a blood sample and this can become life-threatening if the count goes below 50,000 per microliter.

Some reasons platelet production may be less than ideal include bone marrow failure (aplasia), metabolic disorders like kidney failure or alcohol use, viral infections or inherited abnormalities or even bone marrow infiltration like leukaemia or lymphoma (cancer).

Low Platelet Count: 

Platelets, like all blood cells, are made in bone marrow (that’s the softer inside portion of the bone).  If your bone marrow makes too few platelets, the condition is called thrombocytopenia.  While this could be caused by low production it could also be caused by an increased usage of platelets due to injuries.  The count may also go down during pregnancy.

High Platelet Count: 

Too high a platelet count is called thrombocytosis and is normally caused by injury, medication, surgical procedures or diseases.  This increase can cause blood clots within the blood vessels when there is no break in the vessel wall.  That may result in heart attacks, strokes or blood clots in the brain.  Platelet counts above 1,000,000 per microliter of blood are considered dangerous.

How to Fix the Problem: 

The first line of defense in a shortage of production in the marrow would be a platelet transfusion followed by medication.  This is a short-term concern.  Longer term problems may be resolved by replacing ineffective bone marrow with new marrow.  That is what’s referred to as a bone marrow transplant.

On the other hand, there are medicines designed to reduce the amount of platelets produced by the marrow to control thrombocytosis. 

Other Indications: 

One of the newest indications about the importance of the role of the platelet is in the rejection of organ transplants.  Recent tests on organ rejection have shown an alarming increase in the number of platelets and white cells.

Sources:

http://www.netdoctor.co.uk/diseases/facts/thrombocytopenia.htm http://www.aabb.org/events/annualmeeting/attendees/62amonline/Pages/plateletquality.aspx http://www.mayoclinic.com/health/thrombocytopenia/DS00691 http://www.sciencedaily.com/releases/2009/02/090217173038.htm