How big is big? (or how small is small?)

[Kjay]

I was diagnosed with PNH and AA this past January. Since my first diagnosis, the size of my PNH clone has gone from 1%(RBC)/4%(WBC) to 3%(RBC)/13%(WBC). I don't know if these latest numbers are big, small, medium, etc. Can anyone offer some insight?

Kjay

[Gloria J]

Hi Kjay,

I also have PNH, I'm not sure right now how big the clone is, I just had testing done for that. But my LDH keeps increasing, do you have a problem with that also? Anyone else out there with a high LDH??

Thanks!

[nan]

Hi KJAY,
Those numbers are low. Have you gone to the PNH support group yet ? My husband has PNH and we found that site. I learned more about PNH in 1 week from everyone on there ,than I did in 20 years.It is a great PNH website join in and see for yourself you will learn more from that site than any doctor has ever told you and since you were just diagnosed that is great that you can learn a lot right from the start. Best of luck to you. It's PNH disease .org You will not be sorry you checked it out. Hope to see you on there just read and jump in anytime. Check it out Your doctor if a hematologist I'm sure he or she is should have some kind of papers for you that is where I got the site from my husbands doctors gave us some booklets about PNH and it had these different sites. Nancy

[nan]

Gloria,
Most PNH patients have a high LDH. Have you gone to the pnh disease.org if not you should, That is where ( my husband has PNH ) we learned more from that site in 1 week than the whole 20 years he has had it. check it out it was a life saver for us. Nancy

[Marrowforums]

Originally Posted by Kjay

I was diagnosed with PNH and AA this past January. Since my first diagnosis, the size of my PNH clone has gone from 1%(RBC)/4%(WBC) to 3%(RBC)/13%(WBC). I don't know if these latest numbers are big, small, medium, etc. Can anyone offer some insight?

Kjay

Kjay,

Stephen King, an AA&MDSIF board member, provided us with an answer to your question, indicating that you have a small clone size.

Stephen said:

The clone size is now considered the single most important factor in trying to develop a prognosis for a PNH patient after a paper co-written by most of the PNH specialists/researchers in the world in 2006. They consider a clone size of over 50% to be high, and under 50% to be low. Part of that is because in a landmark study done by Dr. Hillmen at Leeds in the UK, they found that without treatment, in a period of 2 years, patients with clone sizes over 50% developed at least 1 clot (and in most cases more than 1) that they could measure, while patients with a clone size under 50% didn't develop any clots. (I believe the study had about 80 participants total.)

The 'real' clone size is the % of the stem cells that are defective/missing the CD55 and/or CD59 proteins. Stem cells develop into all cell lines, so you could measure the clone size of RBC's, WBC's, or platelets, and in theory get the clone size/% from that. However, since RBC's with those proteins missing get lysed, if you measure the % of RBC's that are defective, you get a completely inaccurate picture because many of those defective cells are no longer in the blood by the time you measure (peripheraly). So instead, the best measure is to look at the WBC's that are PNH cells. That gives a relatively accurate number. Even then, different labs get fairly different numbers. I've heard of variations as large as 15% between labs.

The bottom line is that measuring the clone size is best/most accurately done by looking at the % of WBC cells (peripherally) that have these defects/are missing the proteins involved, and if the clone size is over 50%, the PNH is considered serious.

There are exceptions where people with clone sizes smaller than 50% have clots (but this isn't common), or have other PNH symptoms, and there certainly are people with clone sizes higher than 50% who don't clot (as far as they know) even without Coumadin or Soliris or another treatment that may prevent clotting.

[Gloria J]

Thanks, nan, for your advice. I have looked at that site, but I guess not closely enough.

Also, thanks for the explanation from Stephen King. It certainly helped too.

No treatment has been recommended for me, mostly because of my low platelets (currently in the 30s), and I have had no overt symptoms from the PNH.

I will definitely look at the PNH site again, and look forward to hearing my latest results.

[Kjay]

Thanks to nan and to Stephen King for the information. Much appreciated.