Diagnosis process: Hi all What tests did your... - MPN Voice

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Diagnosis process


Hi all

What tests did your haemotolgist order to diagnose ET? I'm under 40 and have had high platelets counts for several years albeit went largely unnoticed until recently. Some of the higher counts were discounted due to infection / inflammation markers however more recent tests have no such indicators just the high platelet count. I ha e no other known health issues - cholesterol, iron levels are fine and no diabetes.

Bloods have been sent for JAK2 and CALR tests. Ultrasound and x-ray for spleen size but that appears normal.

If one of the JAK2 or CALR markers come back as positive is that the end of testing or will a bone marrow test be completed?

At what point will a diagnosis of ET be made / ruled out?

15 Replies

Hi Lina-uk,

I have PV. I was diagnosed from a blood test 12+ years ago, Jak2+. Ultrasound showed enlarged spleen, which doesn’t give me any problems. I only had a bone marrow biopsy 5 years ago before starting Hydroxicarbamide, just as a baseline for the future.

I would imagine diagnosis will be made by the results of your blood test.

Best wishes


Hi. If you have Jak2 / CALR then you definitely have ET or MF (?or PV? not sure ) One of the MPNs, anyway. There is also a third mutation , not usually tested for. . I also had a bone marrow biopsy which confirmed that I had MF. You can also have ET/MF/PV without having one of the known mutations.

If my bone marrow hadn’t shown fibrosis then the diagnosis would have remained ET.

Why does it matter? It affects treatment options and prognosis estimates.

There are some good booklets and links around that explain things in more detail if you’d like.

Do keep posting: lots of helpful people on the forum.

All the best


Hi rachel,interested in ur reply 2 lina as only last week i was reading a medical paper by renown scientists about results of clinical trials,they stated that people can acually ave a certain mutation ie, jak2 & not ave an mpn but cud go on to ave 1 later in life or might never develope1. Sorry i can't remember which 1 i was reading but very interesting read.i think u ave 2 fit certain criteria b4 being diagnosed. Atb,tico.

in reply to Tico

Yes I've seen that too, they tested blood from a large sample of people to see if the mutations occurred without symptoms, which they did. Normally you wouldn't be tested though unless one of your blood counts was abnormal and suggested an MPN, at which point the genetic mutation confirms that you do have one, and the type of cell that is raised (or sometimes counts are low if there is significant fibrosis and it is fairly advanced) plus a bone marrow biopsy, usually confirms which MPN it is 😁


Hi Lina_uk

I’m also under 40 and diagnosed just over a year ago. I had unnoticed high platelets for a couple of years but once noticed I was tested for Jak mutation, infection markers and fibrosis by BMB.

Came back with Jak2 mutation, no infection markers and negative for fibrosis. Was put on Aspirin as numbers were around the 700’s after a year and an increase to 1078 I was started on Interferon Pegasys 45mcg and after 12 weeks platelets are down to 458. Continuing for the next 4 weeks and then will be reassessed.

As soon as I was suspected as having an MPN I was sent in for the BMB, was very overwhelming at the time but in the end it meant I got my diagnosis quicker and a treatment plan put in place. It all happened very quickly for me, my GP noticed my platelet numbers were elevated on a routine blood test and within 1 month I had 3 blood screens, a BMB and a diagnosis of ET.

I had no ultrasound, but I think the BMB is key in determining ET or MF and at what stage.

None of it is pleasant but once it’s done you get to take back control and start to feel better about things.

Good luck with your diagnosis, and keep posting, this forum is incredibly supportive and a vault of very useful information!

Kerry :-)

Hi Lina

I was diagnosed with ET in May this year. Blood tests confirmed Jak2. I'm only on daily aspirin at the moment. I've had one check up after 6 weeks since diagnosis and go back to see my Haematologist in September. My spleen was checked with a physical examination, thankfully all okay at the moment. Seems my platelets have been high since 2003, but like many here, it wasn't noticed til a new gp arrived at the surgery. I've found this forum welcoming and helpful, sure you will too.

Best wishes, let us know how you get on.

Hi Lina,

I was diagnosed with probable ET last October JAK2+ after referral from my GP when my platelets shot up to over 700, my doctor had ignored my high platelets for about 5 years before that 😏I had discussions with my haems and read lots of articles and research, then decided to request a BMB to rule out a different MPN or Pre-fibrotic MF as the prognosis is not so good as it is if it is ET. They haven't done an ultrasound of my spleen, just felt for it. I am 56 and live in NZ. They were happy to do the BMB and I got the lab results last weekend and a copy of the letter to my GP, it definitely looks like straightforward ET based on the BMB so very happy with that as that was the best case scenario 😁 I just wanted to know as much as possible now which I wouldn't have got without the BMB. It also provides a baseline for any change in my ET.

Hope you get your mutation tests back soon and good luck if you decide to ask for a BMB if they don't do it routinely, they may not if you do have a mutation, they will probably just say what they said to me about probable ET and do watch and wait unless your platelets are really high.

Best wishes


Hi Lina. I am ET and JAK2, 66.

I feel you just need to be aware that your GP will know nothing about the condition and the fact that a high platelet count was not noted until a new GP arrived is no surprise to me. It seems GPs do not even realise the existence of this 'disease' and certainly know nothing of either it's or the drug debilitating effects. My usual GP commended the new one for noticing the elevated levels which made me wonder how long they had been raised. I know that I was suffering the symptoms of this for many years prior to the diagnosis, which was done by a brilliant hospital doctor when I (once again) was taken in with a suspected stroke which, as usual, was a TIA.

Having been originally (managed 4 weeks) prescribed hydroxy, I am now on Pegylated Interferon and although many side effects, tolerate it as well as I can and seeing a drop in platelet levels.

All the best


I’m 43, diagnosed ET Jak+ after a blood clot on my liver, no other symptoms. Now (5weeks in) on Interferon Alpha 4days a week and platelets gradually coming down. Only mild side effects of interferon so far, easily manageable with a couple of paracetamol. Platelets were around 850 when clot was discovered, went up to 1000 before treatment and now working down below 600.


I was 48 when I was diagnosed with ET (Jak2 neg). I had an ultra sound/MRI/xrays and bloods 3 times a week for 2 weeks. My Haemo did not perform a BMB because he said it was unnecessary and an ongoing debate on the Panel of Hematologists of which he was a Board Member. I was happy to have a BMB but he told me any markers or changes would be flagged up in my bloods via my DNA and a BMB was not necessary. Who am I to argue. I've asked at previous appointments how will he know if my ET has taken on another MPN and again, he said, because of my markers. It took 2 years for my platelets/liver/HGB to be in range and they have remained in normal range for over 6 months. I have my bloods done once every 3 months before my appointment with my Haemo.


I'm much older than you (72) but was diagnosed with ET in November 2016 although my platelet count was just below 1,000 in February 2014 (I've not seen earlier blood test results). A blood test identified that I am Jak2+. I've not had a BMB and neither has my spleen been physically checked. I am currently on 10 Hydroxy-carbamide per week with a daily baby aspirin. In January my platelets were down to 440. I go for another checkup this week. I have a few minor symptoms - burning feet and painful toes which I put down to ET; and ringing in my ears and thinning hair which I put down to medication.

I had high platelets for 5 years before being sent to consultant. I tested positive for Jak2 mutation and no more tests needed. I now go to consultant annually unless there r problem picked up in bloods so have other test to find bleeds when iron levels were extremely low. Only taking aspirin for now.

in reply to Lizs66

Oh also enlarged spleen

Like you I was in my 30s when diagnosed with ET following consistent high plt counts that, like yours, had been ignored. All the mutations hadn’t been discovered then as it was many moons ago so I had a BMB for diagnosis. Subsequently I have discovered that I am negative to all mutations, although I haven’t been tested for the third one just because I forget to ask.


Thanks all. Will wait and see what the JAK2 and CALR tests say. Hopefully if it is ET as the haemotolgist suspects they'll just keep a watching eye.

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