is what my SF neuro specialist has said in my case as well. Before my acute bodywide onset, I had a pretty bad upper respitory infection for like a month. But... not known to me at the time I also had a long standing gut infection with H.Pylori bacteria which was diagnosed by biopsy.

I have managed to find quite a bit on the internet linking helicobacter infection to Guillian Barre like syndromes. There could even possibly be a slight nutritional component to mine as well, due to the helicobacter infection. I was iron anemic on my blood tests, and the first time I supplemented with B12, I passed out in bed and slept for like 3 hours from 10 to 1pm which was extremely unusual. I also remember on that day that I also for some reason couldn't move my arms after I took the B12.

Just to add one more thing... I have had PN, both motor & sensory in both my legs due to DDD & trapped nerve roots from herniated discs long before I had my acute bodywide onset of SF PN. I just never knew it had a name.