Richard's myeloma story is amost caught up to the present, but as always, there was one more crisis. In mid April, Richard was doing really well. He had lots of energy and eating fairly well. But toward the end of the month, he began to feel tired and went back to his home on the couch. After about a week of this, he lost his appeite again and started to lose a little weight. One evening he asked me to look at his back because it was itching, and there was a bright red, flat morbiliform rash. Here's a picture of a child with measles which is the most common "morbilliform" rash. I've also seen it as the result of a drug allergy.
He called one of the BMT nurses, and the next day we were on our way back to Mayo. The diagnosis was chronic GVHD, graft verses host disease, involving the skin and the liver. It also affects the inside of the mouth, as it did for Richard. I found some images of oral involvement, but they're a little too gross to post, but if you're interested, you can find them here.
About 50% of patient who have allogenic transplants from a HLA -matched donor will develop some degree of GVHD. Most cases are mild, but some are very serious and result in sigificant disability and/or death.
GVHD is the result of donor (graft cells) T-cells attacking tissues that the donor T-cells do not recognize as "self" (host cells). The normal function of the T-cell is to attack bacteria, viruses, and other foreign invaders including cells that are foreign to the host body. On the surface of most human cells is a set of genetically determined markers called human leukocyte antigens. There are ten general types of HLA antigens, and these are what are used to match a potential donor for transplant. But there are many different subtypes within the 10 general types, so no one, except maybe an identical twin. can have exactly the same HLA antigens.
T-cells use the HLA antigens to determine what is "self" and what is not. When non self is detected, the T-cells activate the body's immune response to destroy the "non-self" cells. The greater the difference between the body's and the foreign tissue's HLA markers, the swifter and more vigorous the attack.
GVHD in the first three months after transplant is called acute. After three months, it's called chronic. You can have just one or both. A little is better than none because when the host fights back against the graft, it also may fight the myeloma.
This is Richard's back. He was treated with prednisone starting at a dose of 130 mg daily. Those of you that have myeloma, or are close to some one who has it, know all about the side effects of high dose steroids! That's a subject for another long entry. The good news is that Richard responded well to the predisone and has been able to taper it down to 20 mg daily as of last Monday. His hepatic function tests have also majorly improved, and I have posted those for people like me who like numbers.
GVHD is a very complicted topic.
My forte is family practice, not hemotology. A an easy to understand reference can be found here. A more detailed reference is:
Cutler, C. & Antin, J. (2005) An Overview of Hematopoietic Stem Cell Transplantation. Clin Chest Med, 26, 517 - 527.
You can order it at Loansome Doc or I will send you the PDF if you email me or ask in the comments section.