thanks - yes, I know about Benzene. To be honest its been hard work getting my doctor to give me any tests & he (& other docs in the same practice) have basically said there isn't much else they can do as I don't have the right indicators for other tests. As I said I had to push hard to get them to refer me to a neurologist. Any tips / advice on immune factor tests ? Also, am I right to assume that if I do get to see a neurologist they'll want to explore things like that anyway ?