regarding PN i have learnt everything from the internet. all of the seven neurologists i have seen in hong kong have been totally incompetent. the first one didn't recommend a blood test. the second one did, but did not test for B12. none of them mentioned blood sugar or an OGTT. i could go on but i won't as i now know that my experience is not uncommon. the most useful resource i have found has been this site. so thanks to everyone who contributes. and remember to be tolerant. it can be quite a frightening and confusing experience at the beginning, and it's hard to know who to listen to.