The Not-So-Gentle Answer: 4. Platelets

Lately, when people ask me “how are you?” I have to choose between being polite and being accurate. Most people get the polite answer “I’ve been better”. It turns out I may have been too gentle.

The bone marrow of your pelvis, ribs and sternum produce your blood, about 15ml per day, in adults.  (If you are younger than 18 months old, the long bones in your arms and legs also produce blood cells.)  The interesting thing is that the stem cells that give rise to the blood cells aren’t fixed in place, they “go on tour” from one site to another.  This is how my CLL arose from just one mutation in one cell, once, and yet now all of my bone marrow is involved in producing useless CLL cancer cells.

It is a not-uncommon development of CLL that the portion of the bone marrow producing useful blood cells gets “crowded out”, resulting in a decrease in the production of useful blood cells.  This is not evenly distributed, and different bones may produce different proportions of useless CLL cells vs useful blood cells.  This is not consistent over time, either.  This un-even-ness makes interpreting blood test results difficult, because there is so much “noise”, the trend line is more informative than today’s absolute number.

One of the kinds of blood cells that my bone marrow is producing in very low numbers are platelets, which go by the medical name of thrombocytes.  This is the same root word as in deep vein thrombosis (DVT) that aeroplane passengers worry about.  Thrombus is a Greek word meaning clot.  Platelets are very important in helping you to form blood clots and to plug leaks.  Low platelets can also make you very tired.

The term thrombocytopenia means a deficiency of platelets, but “low platelets” is easier to say, and faster.  The penia part is a Latin suffix meaning a lack or deficiency.  It comes in varying degrees: none, “slight”, “marked” and “profound”.  Looking back over the data, my platelets never returned to normal levels after my 2010 chemotherapy, and have been trending downwards for the last year or more.  The trend line crossed zero a few months ago.

I mentioned, above, that platelets help plug leaks.  Interestingly, your circulatory stream is meant to leak a little bit, that is how your cells get their nutrition.  But too few platelets causes a bit too much leakage. You have probably heard the term petechial hemorrhaging on CSI.  These are small red dots 1-2mm in diameter.  (The big spots in the Wikipedia picture are purpura.)  It turns out you can get petechiae other places than on CSI.  I first noticed it back in April and it resulted in my first surprise platelet transfusion (not two words you ever expect to hear in the same sentence).  I had hundreds of bright red dots up and down my legs.  This is mostly because of the increase in blood pressure in your legs when you stand up, and also why I try to keep my feet up, to minimise the difference in altitude between my heart and my feet.  These days, I have petechiae all over (but mostly arms and legs) in various stages of fading away.

Living in your body, day to day, you often bump into things, and never notice, except maybe for a small graze.  This is not the case for me.  If I scratch or scrape against something, I’m going to bleed, and I will get a huge bruise that lasts for weeks.  This ease of bruising means that I can’t do much karate at all: I can’t take a punch, or give one, no kicks either, can’t block, can’t fall, can’t roll.  (Well, I would if self defence required it, but not at training.)  Long term (chronic) low platelets means that you have bruises all over, in various stages of fading away.

One thing I didn’t anticipate was the intersection of my history of nose bleeds (sometimes they just happen) and thrombocytopenia.  The damn things take ages to stop, these days.  They do eventually clot, and when I blow my nose, they resemble the size, shape and texture of a small bright red garden slug.

And then there is my history with bleeding haemorrhoids doubling down with my thrombocytopenia.  We’ve had a couple of visits from the haemorrhoid fairy recently, and it highlights a problem with chronic profound thrombocytopenia: I could bleed to death.  Sitting on the loo is not the way I want to go.

However, it is equally possible to bleed from just about anywhere, not just from my skin, or under my skin: into the intestines, into the stomach, into the lungs.  But equally well the bleed could be internal, into the abdomen, or into the brain.  This is very scary.  The result is that I routinely get a platelet transfusion every Tuesday, and more than one a week, when necessary.  Without platelet transfusions I will bleed to death.

The platelet transfusions are known as “pooled platelets” meaning they they are pooled from many donors.  Because platelets don’t have a cell nucleus, they don’t produce proteins, and they don’t provoke an immune reaction in the recipient.  That said, they do try very hard to give me blood type specific platelets.  My oncologist is concerned that the transfusions are much less effective than they should be, and is considering using specifically typed platelet transfusions, from specifically selected donors (and yet still double anonymous, Red Cross Blood Service is an impressive organisation).

Sometimes, you can have an auto-immune response where your neutrophils get it wrong, and attack their own host, and this can cause numerous problems.  The oncologist suspects this may be a contributing cause of my low platelet counts.  This can be caused by a whole range of things, including some kinds of leukaemia, and it can also be a side-effect of chemotherapy.

It may be that my bone marrow has been “merely” overwhelmed by the cancer factory (in which case my platelets will recover), or it may be that all the good cells in my bone marrow are all dead (in which case my platelets will never recover).  We can’t tell which is the case until the chemotherapy starts to make some progress, in maybe 3 or 4 months.  If my bone marrow is dead, even if the chemotherapy works, I will die unless I receive a bone marrow transplant, but even if I receive a bone marrow transplant I may still die.

I am confident in my oncologist, I am confident the treatment will work, and I can cope with a few spots and bruises. I accept this gift.

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You may be interested in reading the earlier Not-So-Gentle episodes: (1) Introduction, (2) CLL, (3) Neutropenia, (4) this post, (5) Commensals, (6) Infections.