beyondhom cat scratch "issue"

I wonder if anyone has input about this?

A couple of months ago I got a scratch to my foot by one of my cats.   
This particular cat gets into particularly icky things, and several  
times in the past several years I have had small scratches from him  
that became slowly worse and worse, until bandaged with castor oil.   
(None of my usual anti-infectives, external or internal, made even the  
slightest difference.)

This last time, before I got hold of castor oil it had gone beyond  
what that could clear, and the "something icky" has evidently made its  
way into a nerve in my foot, where it is very happy.

Spilanthes tincture stops it from spreading or worsening (thank you  
Dale for bringing spilanthes to my attention!), BUT seems unable to  
clear it from the nerve.  Each time I go too long without my dose (6-8  
hours), it begins to spread and worsen.  And when I get back to the  
regular dosing, I regain most of the ground that was lost, but not all.

It feels to me as tho my immune system takes NO notice of this  
whatever-it-is at all, and I'm kind of stumped about where to go from  
here.  From standpoint of homeopathic treatment, there's very little  
acute symptomatology to work with because of the spilanthes.

Anyone have thoughts, or heard of anything like this?

Thanks,
Shannon