Increased PNH clone post ATG
 

I have now had 2 rounds of ATG - first round was horse ATG in November 2012 - response was great but unfortunately relapsed in Feb/March 2015. I have just completed a second round of ATG (rabbit) and my PNH clone has increased in size.

I had a very small PNH clone (less than 1%) when I was initially diagnosed with AA in 2012. My PNH clone has post each round of ATG increased in size.

I am interested to know whether anyone else has a similar experience and whether the clone has continued to increase or whether the initial increase post the ATG has remained relatively stable?

Hi TASHMAC,

Glad to hear from you again :) How was your experience with the second round of Rabbit ATG? Are you seeing any response yet?

Is your PNH clone still less than 1%? If so, I wouldn't be concerned as that is still considered sub-clinical.

My PNH clone has also increased in size. I am still sub-clinical though at .99% :)

There are two upcoming webinars through AA&MDSIF that you may find interesting and a good place to ask questions. They are on July 7th and 9th. The first is on long term issues for AA and bone marrow failure patients. The second is on the dual diagnosis of AA and PNH. You can sign up for these webinars through this website:

https://www.pathlms.com/aamdsif

So far it looks like my round of rabbit ATG has gone well. I suffered from very mild serum sickness (headaches, body pains and shaking) while in hospital and one week post discharge developed a very mild rash but this was treated easily with benadryl.

The rabbit ATG definitely knocked my counts around differently to the horse ATG. It is true to its word and completely wiped out my WBC and in particular Lymphs. WBC went down to virtually zero. I had 5 days of the rabbit ATG at a dose of 2.5mg/kg.

Approximately 4 weeks post completion of the ATG my counts are:

platelets 35
hgb 7.1 - I am suffering from hemolysis - unexplained - coombs negative.
ANC 1.6
retic count 3.8
Lymph% 14.1
Abs Lymph 0.30 (L)
WBC 2.13
Neut% 75.1

Since completion of the ATG I have required 1 unit of platelets and 2 units of RBC.

To address the hemolysis we are increasing the steroids. Post discharge from hospital I was taking 60mg per day and had decreased to 10mg. We are now increasing to 40mg. I am also currently taking 350mg of cyclosporine per day.

With respect to my PNH clone, when initially diagnosed (back in 2012) my clone was below 1%. Prior to commencing the rabbit ATG my clone was 3%. As of 3 weeks post rabbit ATG my clone is now 8% (note this is the PNH Granulocyte Clone). My PNH Erythrocyte Clone 0.13.

Hang in there TASHMAC! It is good that your platelets have started to respond.
Hopefully, the RBCs will soon follow. I know it takes a while for the lymphocytes to come back with r-ALG as compared to h-ATG. Do you have an elevated LDH?