von Willebrand disease and ET

I always imagine a character named
Count von Willebrand when I hear
about VWS. He would look something
like Fearless Leader from
Rocky and Bullwinkle.

As an ET patient, you've doubtless been told that both clotting and bleeding can be complications of our disease, and, like me, you've probably been stymied about this paradox. How can we be both clotters and bleeders?

For a small percentage of us, the problem may lie with the von Willebrand factor.

Without getting too technical, the von Willebrand factor is a bunch of molecules that helps control clotting in your blood. Some people are born with a deficiency in the von Willebrand factor, and they have what is known as von Willebrand syndrome (VWS). The chances of you having ET and being born with the even rarer VWS is close to statistical impossibility. In addition, if you had been born with VWS, you'd know it by now.

However ...

For decades, doctors have known that there is a correlation between super high platelet counts--counts over 1.5 million--and a decrease in the von Willebrand factor in the blood, though studies haven't really shed much light on why this correlation exists. The bottom line is that about 11 percent of those with an MPN might develop acquired von Willebrand syndrome (AVWS). Those with ET+AVWS run risks of both clotting and bleeding.

Von Willebrand's is NOT something ET patients should start worrying about. The good news is that even if you develop AVWS, chemo like hydroxyurea (Hydrea) will make the AVWS go into remission, though that remission may not be instantaneous. Before remission occurs, the tricky part for your doctor is making sure that aspirin therapy that prevents clotting doesn't cause a bleeding incident because of the AVWS.

If you have ET and have experienced any kind of internal bleeding, your doctor has likely already tested you for AVWS.

Knowing about AVWS does help explain a few things about your doctors' treatment, especially if you are a candidate for surgery.

Several of our fellow patients with ET have reported that surgeons insisted on bringing their platelets down to near-normal levels before doing surgery. And that's probably a good thing even though it means going on chemotherapy before they really want to (and who ever really WANTS to go on chemo?). Clotting can be a surgical risk, and surgeons want to give you the best chances at avoiding that risk by reducing your platelets. An alert surgeon who knows about the connection between ET and AVWS also wants to make sure that abnormal bleeding is less likely to be a problem if the ET is controlled.

There's lots more info on AVWS in a 2011 article about this in Blood Journal. Get your medical dictionary out before you go there!

Be well!

Related: EM and the weekly poll report 

(This post covers another oddball condition associated with ET, erythromelalgia)

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