I had a similarly quick slide into Aplastic anaemia/hypo-MDS. Back in Oct 2008 I went from running 30k per week and lifting a lot of weights and being very physically fit and active to suddenly being out of breath just walking up a flight of stairs, all in the span of two weeks.
For me, it was a combination of about 4-5 "bad" runs in a row, combined with a series of bleeds in my eyes to tell me something was wrong and seek medical advice. All in all, my bone marrow failed spectacularly quickly, from utterly normal in September to very, very low in June (2 red and 2 platelets every week). They say I was only a few weeks away from total bone marrow failure when I went in for my transplant in July.
Not to say in any way that this will happen to you!! This was just my experience.
I'm really, really looking forward to my first run at the weekend. I hope to do a 10k around my 1 year post-BMT mark to raise funds and awareness for the UK's bone marrow registry charity, Anthony Nolan.
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36/F - 1984 SAA treated with ATG [complete remission until] Oct 08 - burst blood vessels in eyes and low platelets; Jan 09 - AA & hypo-MDS; July 09 - BMT (RIC MUD PSCT) July 10 - 10k for Anthony Nolan (1yr post BMT! 53:48) Sep 10 - Wedding!
I've run 5 marathons now!! (PB 3:30!)