Thrombocytopenia

[Traci]

Herbicides can cause some serious toxicities and health problems, but her liver and kidneys would probably have failed rapidly, and that would certainly show up on bloodwork.

I doubt bugs and beetles are concerning, but blood-borne or other parasites might be concerning. Didn't you say your vet already had those ruled out?

Without further diagnostics, I'm not sure what else to suggest. Unless you can try to think back on things in the home, foods, things in the yard, etc that may be somewhat suspect. I'm just concerned because she had a serious episode last year, seemed to respond to treatment then, but developed this again a year later. It really sounds like something hidden is going on, and I'd at least ask your vet to not stop investigating, even if it's just rule-outs with minimal testing.

[k9Karen]

Like Traci, I haven't heard of any cases of thrombocytopenia caused by insect ingestion. I tried to see if I could google something, but didn't find anything. I did find this article, which seems to be pretty informative (although, I have to admit, I didn't read it in depth)

http://www.idexx.com/animalhealth/educa ... 200402.jsp

The most common causes of thrombocytopenia, at least that I know of, are sequelae to another infection (usually viral, but the tick-borne diseases can also be of serious concern) or autoimmune (I suspect that's what your vet means when he says 'genetic'). A properly performed ANA (anti-nuclear antibody) test should rule-out autoimmune disease. I stress the 'properly performed', because they are not always reported in a way that will allow a definitive decision, and I don't know about vets, but most MDs don't really know how to interpret the results.