Hi vickchick & welcome to mumsnet - and particularly this fostering forum.
Firstly, well done on getting so far... I once heard that only 10% of applicants make it through to panel.
I guess in relation to your health issues, without wanting to pry (me, not panel) , its whether they will affect your ability to provide a stable environment for the children. Also, if your assessing SW is happy to proceed and take you to panel, then she/he must think that these health issues are workable.
Fostering can be incredibly stressful and busy and if any of these factors could adversely affect the illness, then I think everyone should have cause for concern.
Panel in my experience wasn't out to find fault, quite the opposite, and many questions that we thought they'd pick up on they didn't - as our SSW had done such a thorough job in her report we suspect - but obviously health issues can be a huge factor... the last thing anyone would want is to have to move children because of your health....
I'd be prepared to answer why you think you can manage - and lets be honest - sibling groups or multiple placements - will probably be exceptionally hard - and if your health does deteriorate, what contingency plans you have in place... I guess your support network will be crucial to this working too...
Maybe they'd be happy to start you with maybe just 1 child and see how you go...
Maybe they'll want an indepth report from your GP which hopefully has been already covered and what your GP's opinion of your health and fostering... they sometimes send these in advance to their own inhouse medical advisor to prevent any issues at panel... (they did with mine)
I can only say again, that a SSW taking it forward to panel with a recommendation to approve is normally a very good sign!!
The very best of luck and please come back to update us!!
x