Samuel Fry: Day +100: Big transplant news

One thing--one very big thing--that I haven't written about much lately (as if I've written much about anything) is the status of Sam's transplant. To fully appreciate where we are you need to know how we got here.

Back in August we agreed to use a reduced-intensity pre-transplant chemo regimen for Sam because it would be easier on Sam's little body than a high-intensity regimen--less harsh, less poisonous, less likely to lead to long-term side-effects.

We did not like the idea of using more chemo than necessary, and the doctors felt that a standard regimen would be overkill. Sam didn't need his immune system completely destroyed. He needed only for it to be beaten down and suppressed long enough for the donor's T-cells to establish themselves and learn to keep his T-cells--the ones that get over-excited and start attacking him--in check.

This equilibrium is known as "mixed chimerism," and every week the hospital tests Sam's blood to see what percentage of the T-cells in his blood are from the donor.

The first chimerism test after after transplant showed great things: 100% of T-cells were from the donor. But every week that percentage dropped by about 10%; by early November it was below 50% and showing no sign of leveling off.

I started to sweat bullets. Terrified that the transplant was failing, I ran grim scenarios through my head: that the HLH would flare up if the percentage went too low to keep the disease at bay; that Sam would have to go through the entire transplant process again; that all the extra treatment Sam would require (e.g., chemo, steroids, invasive procedures) would begin to break his body down; that Alyson and I would collapse psychologically and emotionally; that Sam would never again experience life outside a hospital, and that he would eventually suffer a long, slow death not from HLH itself, but from the weight of all the treatments, meds, and side-effects (or an infection somewhere along the line).

A few weeks ago the doctors gave Sam 4ml of donor T-cells in hopes that a "surge" of additional cells would help us get the donor T-cell population back up to desirable level. Then we waited, still sweating, for the effects to show up on the chimerism test results--results that take an agonizingly long 7 to 10 days to come back from the lab.

While we waited the percentage dropped to seventeen.

And then a good thing happened: Sam got graft-versus-host disease in the form of a mild rash. Which suggested that the donor cells were replicating and fighting off Sam's own cells.

And then we got the test results back: 79%. A week later we were at 93%. And last Friday we hit 100%.

So we have stepped away from the cliff's edge. It seems unlikely that we'll stay at 100%, but the docs are very pleased--they say the speed with which donor cell percentage rose bodes well for long-term success. It will still take weeks to see where--and if--we reach the desired equilibrium, but at least we're breathing again.

Today, December 25, 2015, we are celebrating our first Christmas with Sam. Even though Christmas really came a week early.