Private Medical Insurance - Pre-existing Conditions

[RaeCJ82]

Does anybody know how Insurance companies define pre-existing conditions?
Let's say I have been having trouble with my nose, breathing and some scabbing. An ENT consultant wants to run tests for vasculitis which come back negative. If I was to then purchase medical cover, go for more tests and it turns out that there is a structural problem with my nose which requires surgery, would this be seen as a pre-existing condition?

Very probably.

You have an issue, and the cause has not been fully established, so the tests for which the need is already known (to get to the bottom if the pre-existing symptom) and any treatment following those test results will almost certainly be excluded

Yes this is what I suspected. Will just have to attempt to stick it out and wait for the NHS appointments.