11: Hematology for dummies

We’re just about at the 2-month anniversary of this blog, so thought I’d take some time to talk very simply about the science behind my diagnosis and treatment.

I’ve recently been reading a bit about hematopoeisis,”the formation of blood cellular components. All cellular blood components are derived from hematopoietic stem cells. In a healthy adult human, roughly ten billion to a hundred billion new blood cells are produced per day, in order to maintain steady state levels in the peripheral circulation.”

Billions. Hundreds of billions. That’s a lot of blood cells.

My diagnosis

As those of you who’ve followed my saga from the beginning, you know that it was discovered following routine annual physical blood tests last October that my bone marrow had nearly ceased producing blood cells (my blood cells were down to 5% while normal for my age group would be around 34%). I was diagnosed with aplastic pancytopenia (aplastic anemia), “a severe hematologic condition in which the body fails to make blood cells in sufficient numbers, and is associated with cancer and various cancer syndromes. Blood cells are produced in the bone marrow by stem cells that reside there. Aplastic anemia causes a deficiency of all blood cell types: red blood cells, white blood cells, and platelets. (source)

My latest CBC test results.
Note WBC, RBC and platelet counts

A basic graphic on how blood cells are formed and differentiated.

My treatment plan

To put it very simply: in December I underwent immunosuppressive therapy (anti-thymocyte globulin [ATG] along with cyclosporine) conducted basically to eliminate the “killer” (cytotoxic) T-cells that were destroying my bone marrow. Following the 5-day ATG treatment, I began a new treatment regimen of daily eltrombopag (along with cyclosporine, both of which I'll be on for at least a year.) This combination will hopefully help my bone marrow regain normal functioning again.

Joel helped me understand the process this way:

The current theory on autoimmune diseases is that “helper” T-cells are targeting cells for destruction that shouldn’t be destroyed. To use a contemporary metaphor, “helper” T-cells carry proteins that they put on “intruders” (viruses, bacteria, etc) – like a tracking device - which then signals the “killer” T-cells to destroy them. Cyclosporine (a med used for transplant patients to prevent organ rejection) is designed to limit that protein (or tag) production. So, the process was/is: kill off as many “bad guys” as possible in the first attack (ATG), limit the damage that the remaining “bad guys” can do (cyclosporine), and build up all the good guys in the bone marrow (eltrombopag). 

Though it seems I’ve been on this path for ages, in reality it’s actually been just over a month since I started the eltrombopag. According to all the studies we’ve read, true results won’t really show up until about 3 months in. So for now, I need to be patient and look forward to positive signs, hopefully by early April. 

Some interesting graphics

As a human develops, stem cells are produced in different areas of the body. In utero, stem cells are produced in the organs. After birth, stem cells are produced in the bone marrow, but the specific locations change over time with a person’s age. (Human umbilical cord contains an incredible number of stem cells. If you, or someone you know is pregnant and interested in donating cord blood cells, please share this link.)

Hematopoiesis by age

Hematopoiesis by location in older adults

How it feels after nearly ever blood test, and in which my bone marrow is The Anomaly?

Click to play - from STTNG "All Good Things"