Why Does Blood Clot In Tubes Collected For Biological Tests?

Posted on Mon, 14 Sep 2015

Medically reviewed by Ask A Doctor - 24x7 Medical Review Team

Mon, 14 Sep 2015 Answered on

Mon, 5 Oct 2015 Last reviewed on

Question : My friend has Anklelosing spondilitis and is on remecade. When he goes for his treatment they take his blood for testing each time. The last time one of the tubes that were taken clotted in the tube. They said this happens so they did two more test and the same thing happened. Now they want him to go to another lab and have the test to see if it happens again. He has been on remecade for about two years now. I'm his friend and get worried easily. He is also a smoker. What would cause this to happen? He is 58 years old.

Answered by Dr. Luchuo Engelbert Bain (7 hours later)

Brief Answer:
Possibly lack of good quality anticoagulant in the tubes used

Detailed Answer:
Hi and thanks for the query

I understand this can be disturbing. but I can reassure it is nothing serious to be that worried about.

Generally, the tubes used in collecting blood samples contains special anticoagulants to prevent blood from clotting. lack of this anticoagulant or poor quality coagulants or at times tubes that have stayed unused for long can fail to produce optimal anticoagulatory (anticlotting) properties. This will cause blood to easily clot in a couple of minutes. Clotted blood is not ideal for most biological tests to be carried out upon.

Especially if this happened only this time around with this lab, it has to do with malfunction of the tubes or anticoagulant rather than your friend having any specific problems.

thanks and kind regards. do not hesitate asking further questions for clarification in case of need.

Dr Bain

Above answer was peer-reviewed by : Dr. Sonia Raina

Follow up: Dr. Luchuo Engelbert Bain (8 hours later)

The problem is is has happen three times now. So they are send ing him to another clinic. Could it be something wrong with his blood. Or something else?
Sorry to bother you. Not sure if my reply went through as I was using a IPad.
The clotting happened three times from the same lab. He is now being sent to another lab. Is there any other reason for this to happen? One of his test a few months ago his white blood cell count was up a little. Can that happen from being on remecade?

Answered by Dr. Luchuo Engelbert Bain (2 hours later)

Brief Answer:
It is possible, very unlikely in this case. Check with another lab first

Detailed Answer:
hi and thanks for the query

I think we need to start worrying if it happens again in the new lab. Remecade is very unlikely to cause such a condition.

it is more likely the equipment in the former lab had issues.

yes there are blood conditions like some clotting factor excesses and defficiences that can cause excessive blood clotting. we can only start thinking of this if it repeats in the new lab.

I feel we need not worry as of now as we await.

thanks and ki d regards

Dr Bain

Above answer was peer-reviewed by : Dr. Vinay Bhardwaj