What are Platelets?


Platelets, along with red cells and plasma, form a major proportion of both human and animal blood. Microscopically, they look like little thorned or spiky ovals, and they can only be viewed microscopically, as the average size is about four hundred thousandths of an inch (1 to 3.5 um). Platelets are actually fragments of the cells in bone marrow, called megakaryocytes. Stimulated by the hormone thrombopoietin, platelets break off the megakaryocytes and enter the blood stream, where they circulate for about 10 days before ending their short lives in the spleen. In the healthy body, thrombopoietin will help to maintain the count of platelets at a normal level, which is approximately 4.2-6.1 million of these tiny cells in two hundred thousandths of a teaspoon (1ul) of blood.

Most are familiar with the blood's ability to coagulate should one receive a cut or bruise. Specifically, platelets provide the necessary hormones and proteins for coagulation. Collagen is released when the lining of a blood vessel is damaged. The platelet recognizes collagen and begins to work on coagulating the blood by forming a kind of stopper, so further damage to the blood vessel is prevented.

A higher than normal count of platelets, known as thrombocytosis, can cause serious health risks. Too much clotting of the blood can lead to formation of blood clots that can cause stroke. Conversely, lower than normal counts can lead to extensive bleeding.

However, in some cases, inducing a lower platelet count is desirable, for instance if a person has susceptibility to strokes or has had extensive heart repair. Platelet counts can be lowered by a daily intake of aspirin or other clot reducing drugs. Additionally, when a patient has an intravenous drip (IV), heparin is used to keep the IV from clotting so fluids can be either taken from or added to the body.

While disease or a genetic disorder can cause a lower number of platelets, other times, they are depleted because of a specific treatment or surgery. Burn victims, organ transplant patients, marrow transplant patients, those undergoing chemotherapy, and those who have undergone heart surgery often require not only blood transfusions but platelet transfusions as well.

Almost anyone who is able to donate blood, and is not taking aspirin or other anti-coagulants, is also eligible for platelet donation, called platepheresis or apheresis. In this case, blood is drawn and placed in a centrifuge, where the platelets are separated from the other blood products. The rest of the blood is returned to the body, instead of being collected as it would be in a regular blood donation. The procedure takes from about 90 minutes to two hours.

Once collected, platelets only have a shelf life of about five days, and one donation provides only a sixth of a platelet transfusion unit. Given that bone marrow transplant patients often require up to 120 units of platelets, it is a foregone conclusion that new platelet donations are required daily. Information about platelet donation is available from local blood banks.

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25
My wife is pregnant and her platelet count is 76000. I want to know how to increase her platelets before surgery. There are only 15 days left and i also want to know if is there any risk if surgery must be done.
- anon51767
24
my name is varun from ludhiana punjab. my problem is that my platelet is very low. it is only 8000. i am a 26 year old guy, so that is why i am not thinking about marriage. please suggest what i can do. i have been suffering ITP for the last 10 years. - Varun
- anon49369
23
my platelet count is 84000. what is the side effect of this and how can i incresse it up to normal range. can you also tell me what are the results of low platelet?. -- raman jha
- anon48075
22
My mum was diagnosed with CLL (stage 2) in 2000. She has her blood sample taken every month by the district nurse every month so that the doctor can monitor my mum's condition. My mum's platelet count from her recent blood test reads 142, HB 10.50, wbc 111. I am concerned about my mum's platelet count because it has never been so low. Is this a sign of worsening of her CLL disease? Does she need any immediate treatment?
- cfc123411
21
Would platelets and plasma be considered the same thing?
- anon44011
19
What type of natural routine diet can increase platelet count?
- anon43625
18
Hi. My blood platelet count is 145. is that normal or not? Please advise me. Thank you.
- anon40080
17
A healthy, desirable platelet count for adults ranges between 150 to 450 K/UL.
- spasiba
16
The last line of this article contains a statement which may be misinterpreted. It states, "...one donation provides only a sixth of a platelet transfusion unit." That is only true if the platelets are derived from whole blood donations. If the unit is the product of apheresis, 1 to 3 complete units of platelets are produced from a single donor. That's the beauty of apheresis- a patient could get three units of platelets in their treatment (not uncommon) from *one* donor versus 18 donors using the derived platelet method.
- rdgarcia
15
Dedicated to anon17078.

I was diagnosed with ITP when I was one-year-old: its typical symptoms- petechiae, excessive gum and nose bleeding and a platelet count from 8000 cu/ml to zero. As cortisone treatment had had scarce effects on me, doctors proposed the spleen extraction, when I was five years old. My mother refused. Remaining nothing to be done from the doctors' part I was sent to the streets and playgrounds, doing whatever the other children were doing. I remember myself usually returning home with some bruises or stop playing due to a nose bleeding.

Little by little the typical symptoms begun to recede and about the age of fifteen they disappeared, whereas the platelets, since then in rare occasions counted, were as always low. When I was about the age of thirty, a doctor, rather intrigued by the situation (platelet count no more than 20000 and daily weigh lifting in the gym), after having examined me squarely (bone marrow, platelet anti-bodies, spleen scan) told me that there are some rare cases where the brain's center, which regulates the number of platelets, is erroneously programed by itself. I am fifty four- year-old now and, be it a mild ITP or a...loose brain valve, the whole thing for me has been a difficult infancy, a careful childhood and an obligatory platelet transfusion when I had a routine operation, ten years ago.

I wish the only helmet necessary for your son will prove that which he will wear in the army.

- anon22290
14
i had a bad case of itp 3years ago, i was 19 at the time. have had no problems with it since... im just wondering what are the chances of it returning?? asking as we want to try for a baby but my biggest fear is that it will return while im pregnant!
- anon21402
13
Food rich in vitamin k (such as lettuce) are supposed to increase the number of platelets in your blood, I dont know why but even if it's not extremely successful eating lettuce isnt going to do you much damage is it?
- anon17374
12
Hello to all you "wonderers" of ITP out there. I have a 2 year old son that was diagnosed with ITP about a year ago. He has for a few months now been deemed chronic. Traveling to the doc's office for *another* blood test. Sometimes 2-3 times a week... We did the steroids and the intravenous deal a couple of times. That only worked for a couple weeks max. So...not wanting our son to have to go through any more of the side effects that those treatments had to offer, we chose to discontinue treatments. As of today his platelet count is 4,000. Yea it sounds really spooky but we have done tons of research and are very comfortable just being extra careful so he doesn't impact anything too hard with his body, and for his head, when he is playing he wears a helmet. There is only a 1% chance of spontaneous bleeding in the head or body, so we decided to take the chance. We have had him off of medication for about 1 1/2 months now. His platelet count has risen to 8,000 on its own, but then dropped to 4,000. I am currently giving him shark liver oil and a multivitamin every day. I am also researching the Macrobiotics diet to see what foods may help him and what foods may not. We have so many allergies for food that we don't even recognize usually when we are having a small allergic reaction. I feel that by eliminating these problem foods and products, his body will have a really good chance at working on the real big problem (ITP).

To all of you ITPers out there...hang in there. Don't panic if your count goes way down...you just have to be careful about the way you go about every day life until your count returns or not. We are so hoping that by letting our son's body have some time to battle this on it's own without constant help from "bad" medications, that his count will return and he can have a normal life.

Hope this helps someone.

- anon17078
11
try kamangi. it really regenerates the number of your platelets.. we already used it to our patient suffering dengue fever.
- anon16175
9
I have been donating platelets for the past 20 years. Because they are short-lived, one can donate platelets MUCH more frequently than can be done with whole blood. The FDA limits donors to 24 times per year, but exceptions can be made if a patient is desperate and other donors are not available. (Several years ago, I was the only donor available and gave 5 times within two weeks, to no ill effect.)

Many lifesaving medical treatments require platelet transfusions. Cancer patients, those receiving organ or bone marrow transplants, victims of traumatic injuries, and patients undergoing open heart surgery require platelet transfusions to survive. Blood type (ABO) and Rh factor (positive or negative) matching is needed, and for some patients, antibody tissue typing (as for transplant) as well.

Because platelets can be stored for only five days, the need for platelet donations is vast and continuous. Normal platelet counts range from 150,000 to 400,000 per cu/ml (THIS IS NOT WHAT IS STATED ABOVE). However, because of their short lifespan, platelets are continuously and rapidly produced in the bone marrow, and even frequent donations generally don't have an adverse affect on platelet counts (which can vary significantly from day-to-day or week-to week.

Unfortunately, there is little evidence of any effect on platelets from diet, exercise, or other means (including sexual activity. Only medical interventions can treat platelet deficiency.

- anon13104
8
Recently, my mom's (48 years) platelets suddenly got lower to 10,000 and then it went to 800 but after 1 day with initial treatment it went to 5000. She also got the test 'bone marrow' and the result was ITP. Doctor has started 3 days steroids course through veins, but is going to check the platelets after 2 doses. As per Doctor's advice she has to take oral steroids for 4 weeks. So my questions are:

Will the platelets increase after this treatment? Will the platelets go down again in future? What are the precautions to be taken for the life time? Is eating types of food a solution or what?

How much platelet counts are preferable for her throughout the life?

Hope to get a good advice and the proper satisfied answer. Thank you so much.

- vaishakhi
7
I am suffering from low platelets count since 2 year when bleeding from my nose then my platelets are 24000 after some treatment my platelets counts are 72000 but when I stop the treatment then my platelets comes to 42000 so what can I do and please suggest me any medicines please and also size of my spleen was 13 cm in Ultra Sound report. I’ll be very thankful to you.

And please tell me that there is any problem in platelets count reducing when I done my sexual job with my wife. Thanks again

Allergy

- anon11852
6
my platelets were 138 and my doctor said normally they should be 150 i know it is still okay and they are not dangerous, and i also know that when they are under 100 that is when i should be concerned, when i was pregnant my doctor said that they shouldn't go under 70 but at one time they did go to 64, my Question is what can do (is eating types of food is a solution or what) thank you.
- anon11596
5
My platelet count came back as 85. Is that bad and wot are the dangers of being low?
- Jgreenham
4
what is the type of shirt with frills on the sides of the buttons called?
- zaheir
3
What do you call the type of shirts worn by pirates?
- zaheir
2
My platelets count has been high the last few times I have been to the

doctor. It was 614 the last time I went. Is this cause for concern and what do you need to do to lower your platelet count?

- anon4427
1
I understand that platelet counts can go up in regular donors. If this is true, how much do they go up, and does this present a health risk to the donor?
- anon2356

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Last Modified: 09 November 2009

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