Pre-diagnosis advice - persistent mild thrombocytosis

[DS00]

Hello. I'm still waiting to see a haematologist but worried I have ET with no symptoms but a persistent mildly raised platelet count of around 460-480 over three years and no obvious reactive cause. I'm 41 years old.

My GP as well as a doctor friend say my platelets may just naturally be slightly high, but I'm concerned because none of the literature I can find online allows for the possibility of thrombocytosis that is neither reactive nor an MPN.

I also wonder if it could be connected reactively to e-cigarette use, which I have now stopped, or covid jabs and bouts of flu several weeks before each of my three tests, but these theories seem a stretch especially given my CRP and ESR readings are normal.

While I see papers and forum posts that say some people with ET started with only mildly raised platelet counts, I can't find any data on how many people with persistent raised platelets and no diagnosed reactive cause do in fact have an MPN.

I'm aware that the genetic and bone marrow tests are required for a definite diagnosis, and that this forum is weighted toward those who do rather than don't have MPNs. However it would be good to know if anyone has knowledge or experience I might find useful. Thank you.

[hunter5582]

Hello and welcome.

While it is the realm of possibility that you have a mild variant of ET, you may also just be someone who ranges on the high side of the platelet reference range. Something very minor could push you past 450 due to reactive thrombocytosis. Still, it is better to be safe than sorry. It is very reasonable to start with a MPN Myeloid panel to check for JAK2, CALR, and MPL mutations. Once those results are in, you can decide whether a BMB is needed.

Watch and Wait = Watch and Worry. it is very reasonable to seek a more clear answer sooner rather than later. This may well be a tempest in a teapot, but best to be certain.

[DS00 in reply to hunter5582]

Thank you for the kind reply, it makes me feel better to be reassured that ET isn't a sure thing, even though it can't be ruled out yet. I am assuming the haematologists at UCLH will send me for those tests once they get to me. I will post again here whatever happens, as I have learnt from browsing the posts here that it can be useful to others when people report back.

[Lola367]

Hi DS00, am sorry you have this worry at the moment, it is really hard when you don't have all the answers and I was in a similar position to you 3 years ago. I was 45 and my platelets had been around 480-500 for approx 3 years. My GP sent me off to see a haematologist who couldn't find any reactive cause therefore tested me for the known MPN mutations. It was a huge shock at first when I tested positive for JAK2, however later on I was actually relieved to know the cause. I didn't have any symptoms at the time but knowing meant I could take steps to reduce the risk of a blood clot. I continue to live a normal life (although health and wellbeing has become a top priority!) and firmly believe that knowledge is power - it's always better to know so you can do something about it! Remember that MPNs are very rare, you are doing the right thing by getting checked and I hope things work out well for you - keep us posted.

[DS00 in reply to Lola367]

Thank you for sharing. If it does turn out to be ET in my case it is nice to know there are people with a similar history to share notes with. Glad to hear you are doing well! David.

[Mustang50]

Hi just keep going back to Gp if your worried and still not right took me 5 years to get diagnosed, I knew in my own mind something wasn’t right keep plugging best wishes

[DS00]

From my experience it can be helpful when googling one's condition to find out how people's cases turned out, so I will briefly update.

I have been told I don't have an MPN as I'm negative for the genetic tests and the doctor, a consultant MPN specialist, said a BMB isn't necessary for triple-negative patients with a platelet count that's only mildly raised (below 600) and no other symptoms or relevant abnormalities. I hope that might be reassuring for anyone else awaiting diagnosis whose platelets also run slightly high for no obvious reason.

Thanks again for the replies here, which helped a lot with my worry.

(Edit to add, the doctor I saw is also an academic expert on MPNs and told me his advice corresponds to forthcoming UK national guidelines that he is helping to draw up).

[RoundTheWorld in reply to DS00]

Good news! And thanks for sharing.