Q: What’s 6’4″ and black and blue all over?

A: Patient Zero

That’s what they are calling me in the Apheresis unit at MD Anderson.  On Tuesday my platelet count dropped to zero (normal is 140 to 440).  My nurse said she has cared for stem cell transplant patients for 20 years and has never had one achieve a platelet count of zero. I guess I am trying to be an overachiever.  If there’s a record out there, I just instinctively try to break it. Even slight pressure on my skin causes bleeding under the skin and bruising.  I tell everyone who notices my bruises that Mary Pat can be really abusive at times.

This is a cautionary tale for stem cell transplant (SCT) patients.  Whether you had a transplant to treat leukemia, multiple myeloma, or some type of lymphoma, it is easy to be lulled into a false sense of confidence once your transplant appears to have worked.  That’s what happened to me.  I got cocky.  After nearly a year of wearing a surgical mask, avoiding crowds, and avoiding children and pets, I decided that my new immune system was working ok and I went back to as normal a life as possible.  I ditched the surgical mask, stopped constantly dousing my hands with antibacterial gel and started going to crowded places and restaurants.  I even went to the Texas Renaissance Festival several weeks ago.

What I didn’t fully appreciate is that my immune system is equivalent to that of a nineteen-month-old child. It is not yet mature.  If it is exposed to a virus like the flu, mumps, or measles, my immune system screams “stranger danger” and sends my killer cells out to kill anything that might resemble that virus.  Unfortunately, sometimes viruses carry a protein on their surface that mimics a protein on the surface of my platelets.

I have received platelet transfusions for the past four days and each night my killer cells have killed off the new platelets.  The condition is called Immune Thrombocytopenic Purpura (ITP).  There are about 200,000 cases of ITP every year in the United States.  Most of the cases involve children with immature immune systems (similar to SCT patients).  In some cases, the count falls below 10 causing intracranial hemorrhage. Half of those cases are fatal.

ITP is a mixed blessing.  SCT survivors who come down with ITP tend to have lower blood cancer relapse rates because their immune systems eventually mature to become efficient killers of abnormal cells. In my case, my new immune system, thanks to my brother Mark’s “Tiger Blood” killer T-cells, is brutally efficient at killing off viruses.  My new immune system just hasn’t matured enough yet to tell which cells are actually mine and shouldn’t be killed.

Dr. C has been hitting me with 100 mg per day of  the steroid prednisone which is designed to suppress my killer cells.  He is also giving me four days in a row of intravenous immunoglobulin (IVIg) which is designed to fight whatever virus is causing the ITP.  I am making slow progress.  In the past three days I’ve climbed from a platelet count of zero to three yesterday and fourteen today.  We’re going to try one more day of IVIg tomorrow and let things rest over the weekend to see if my count begins to recover on its own with a little help from the prednisone.

A growing number of parents are refusing to vaccinate their children which puts other children and SCT patients at great risk.  In Travis County, Texas alone, up to 20% of parents have filed for non-medical vaccine exemptions for their children.  That means a drop below the roughly 95% vaccination rate necessary to keep childhood disease from spreading through the community.

Here’s my advice for  my fellow SCT patients who are complacent or cocky like I was.  Remember that your immune system is still immature like a child’s and can be triggered into over-responding to a random virus.   If you notice abnormal bruising, blood blisters, or excessive bleeding, get to a doctor or an ER as soon as possible.

To all my loved ones and friends, don’t worry.  I’ve got this.  This cat still has nine lives. Onward and upward folks.