Post ATG Update

Nathan finished four days of a medication called ATG and now we are waiting to see the effects. It generally takes several weeks, up to three months, for the marrow to rebound after this treatment but his doctors likely won't give him quite that long due to some complicating factors in Nathan's case and the fact that he has a sibling bone marrow match. ATG is a fascinating medicine. In very basic terms, they take human T cells, inject them into an animal (in this case, a horse), let the animal create antibodies against those T cells then inject those antibodies into a person as a form of immunosupression. The objective is to lower his white cell and neutrophil count essentially to zero and then let his marrow regenerate (hopefully) healthy cells and a more balanced immune system that will no longer attack his cells. The other hope was that his liver inflammation would calm down due to this T cell suppression, thus making a possible future bone marrow transplant less complicated, and it seems we have at least partially accomplished that objective but only time will tell... As always. 

While we wait for his marrow to rebuild, he is taking a medication called Neupogen which stimulates production of Neutrophils which are the white cells that fight infection. Once his neutrophil count is at a safe level, above 500, the neupogen will stop and we will see what his body does. This could take a couple days or several weeks, it all depends in how his body responds. Lastly, they are reducing his steroid dose today as it was doubled while he was on ATG. Over the coming weeks they will likely wean him off the steroids completely.  

Today's labs are the first after a full day off ATG and on Neupogen. Most numbers are not terribly indicative of anything given all the blood products and immunosupression he has been given but I wanted to include them here for our own reference. Normal ranges are in parenthesis after each number for comparison. 

WBC: 0.2  (4.0-12.0)

Neutrophil Count: 158 (1400-6600)

RBC: 2.69 (4.0-5.3)

Hemoglobin: 7.1 (11.5-14.5)

He's likely getting a red cell transfusion tomorrow

Platelets: 37 (150-450)

This is two days after his last platelet transfusion, the longest amount of time he's gone without getting platelets since this journey began. Seems like we have at least slowed down whatever process was consuming his platelets so rapidly, likely his liver/spleen. I am guessing he will get a platelet transfusion tomorrow as well, they are trying to keep him above 20 for the time being but that threshold could be reduced to 10 soon as he has gotten into single digits with minimal symptoms in the past. 

Liver enzymes

AST: 372 (23-58)

ALT: 685 (6-35)

Both of these enzymes were above 3000 at one point so today's numbers almost look normal albeit still elevated. 

Bilirubin

Total Bili: 5.9 (0-1.1)

Conjugated/Direct Bili: 2.2 (0-0.0.3) 

His bilirubin will become even more elevated with each red cell transfusion but today is near as low as he's been this whole time and he looks much less yellow the past few days too

While the above liver numbers are signs of inflammation (aka hepatitis), it seems the liver function continues to be normal despite all this prolonged inflammation. 

The last strange mystery is that his tacrolimus/ prograf level is so low despite his extremely high dosage. Our doctors have never even given a dose this high yet he's still just under therapeutic levels. For now they are leaving the dose as is and seeing what happens over the coming days/weeks. 

Tacrolimus Dose: 15ml twice a day (30ml/day)

Tacrolimus Level: hovering in the 4 range, 6-15 is therapeutic, doctor ideally wants him around 8-12. He is metabolizing this medication extremely quickly. 

So basically we are in another holding pattern and Nathan remains a medical mystery with symptoms of various diagnoses yet none that fits exactly. For now they are going with the closest fit which is severe aplastic anemia with CD8 predominant T cell activated acute hepititis. In the meantime, he has handled all of the medications with minimal side effects and a continued happy and easy going attitude.