Pulmonary Embolism Support Group
By far the most common form of pulmonary embolism is a thromboembolism, which occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes to the arterial blood supply of one of the lungs. Symptoms may include difficulty breathing, pain during breathing, and more rarely circulatory instability and death.
I think I wrote a response to your post in the discussion area. The Factor V Leiden test is often reported as a positive/negative test, but this is not actually accurate. You can be negative, heterozygous or homozygous. People who are homozygous factor V leiden have big clotting problems most of their lives.
People who are heterozygous factor v leiden may never even know it, though their risk for developing clots can be much higher than the general population. Many physicians report heterozygous as "negative," which is not accurate. Please do make sure your daughter is truly negative, and not heterozygous.
As for getting retested, I support that. If you can go to a different physician and lab, that would probably be ideal.
My father and I are both factor v leiden heterozygous. He had a PE two years ago when he was 67. He survived many injuries, broken legs, immobilizations, plane trips to china, spinal surgeries, etc in the years before that without a problem. I had a PE a couple of months ago and I am 37 and in great health with no risk factors (other than the mutation). It doesn't always make sense.
I think it does not hurt to be skeptical, but don't rule out the possibility that the test was accurate. A retest is worth it for peace of mind alone.
I had done similar things for 25 years with no apparent ill effects. However, a year and a half out I asked them to do the doppler on both legs, not just the bad one. Evidence of chronic small clots was found, so indeed there may have been several small incidents, none of them particularly noticeable, until the big one.
No one among my kin showed trombotic tendencies, but one of my aunts had several miscarriages in addition to one child carried to term.
With FVL, the lifetime odds of getting PE run about 10 per cent. A majority of those who have it do not know it, but once it escalates into a trombotic incident things are not the same again. Those with the heterozygous variety have the best chance of a return to normalcy.
Restest by all means as desired, but it is not unusual to go through a lot of normal things for the better part of a life with no ill effects.