ET and PV

[sweetiecake]

Hi all I was diagnosed with ET last month after a positive JAK2 and various symptoms (of which I thought I was aneamic) so came as a shock. I have been on Interferon for 4 weeks and went back today and got told my red blood cell count is high and PV got mentioned! Can you have both or is it one or the other???? My platelets are 850 and red blood cells 48%!!! Confused.com 🥴

[charl17]

The JAK2 mutation can manifest as ET or PV or sometimes as myelofibrosis. Have you had a bone marrow biopsy?

As to your treatment with interferon, this therapy can be employed for ET or PV. It works faster on the platelet count than with red blood cells because platelets turn over much faster. If you have PV they will want to control your hematocrit closely to prevent thromboses.

[sweetiecake in reply to charl17]

Originally when diagnosed with ET I got given clopidogrel and told I would only need further medication if my platelets went above 1000 or I reached 60 as I’m only 41. I was then sent for a bone marrow biopsy and when the results came through I was told there was no mylefibrosis but was put on interferon. 4 weeks of interferon and I return to see yet another consultant who tells me my platelets are high but so is my red blood cell count. It’s so hard as you have to go to appointments alone due to Covid and I’m trying to process 1 big of information and they’ve already moved on to something else. All I know is that my blood test done today is being sent to lab and if red blood cell count is high I will have to go and have blood drained weekly until ok then monthly.

[Minu68 in reply to sweetiecake]

A friend of mine started recording her time with her specialist on her phone, so that she could listen again as she struggled to take in the information. Might be useful for you.I have ET, JAK2 positive, and since my diagnosis las t year have become much more knowledgeable and able to understand what is going on better. It takes time to take it all in, process what is going on for you on all levels, so you have my sympathy! take care x

[cmc_ufl]

ET and PV are very similar, but they are distinct conditions. ET always presents with elevated platelets. PV always presents with elevated RBC measures, and usually (but not always) presents with elevated platelets.

The most important criteria in a PV diagnosis over ET are the hemoglobin and hematocrit values. Among other criteria, PV requires the following:

Hemoglobin >16.5 (men), >16.0 (women)

OR

Hematocrit >49% (men), >48% (women)

See the link below for the full diagnostic criteria for various MPNs:

mpnconnect.com/pdf/who-diag...

[hunter5582]

I was diagnosed with ET about 30 years ago. It progressed to PV about 8 years ago. About 60% of people with ET are JAK2+. 95%+ of people with PV are JAK2+. The JAK2 mutation can cause more than one problem. ET and PV are not the same thing, but do have similarities.

ET = thrombocytosis only

PV = erythrocytosis. PV may or may not also have thrombocytosis and/or leukocytosis.

There are several features used to distinguish ET from PV. You will find that in the WHO diagnostic criteria. mpnconnect.com/pdf/who-diag...

Evaluating erythrocytosis is gender specific. Men tend to run naturally higher than women. Evaluation of erythrocytosis is more than looking at RBCs alone. Typically Hematocrit (HCT) is used to assess your status (which is the 48% figure you cited). HCT = % of total blood volume comprised of RBCs. This number is really just a rough estimate since it also reflects plasma volume.

It is possible for ET to be confused with PV, particularly early in the diagnostic process. It is not always clear and sometimes requires a bone marrow biopsy to make the distinction.

Treatment for ET and PV is similar. PEGylated Interferon is used to treat both conditions. For many of us with PV, PEG alone may control both thrombocytosis and erythrocytosis. Some people with PV also need therapeutic phlebotomies to lower the HCT to target levels (45% for males, 43% for females). Controlling erythrocytosis is the key to PV treatment. It is actually what causes the greater risk of thrombosis. It also causes hyperviscosity of the blood, resulting in hypertension and other problems.

The target for thrombocytosis is ideally case-specific. Many MPN experts now use a target of 600 for ET. There is not particular value in making platelet levels normal per the current thinking by many MPN experts.

silvermpncenter.weill.corne...

What really matters the most is effectively controlling the symptoms of MPNs. We experience many different issues besides the risk of thrombosis. We can also experience hemorrhage, microvascular symptoms, fatigue, insomnia and many other secondary symptoms. Whether you have ET or PV, the issue is to control for symptoms and risks and maintain a high quality of life.

Hope that answers some of your question.

[Wyebird]

Oh bless you . I bet your head is already a mess without having another diagnosis thrown in. There will be plenty of people here more qualified than I to respond informatively. So all I can say is welcome to this amazing site

[Mazcd Partner MPNVoice]

Hi Sweetiecake, welcome to our forum. It is very daunting when you are diagnosed with a MPN, there is such a lot to understand and learn, we have a lot of information on our website that will help you, mpnvoice.org.uk

I would suggest that you contact your haematologist, or your haematology nurse specialist to ask them to explain why your diagnosis was ET and now they are mentioning PV, as you do need to know. Best wishes, Maz