Hey Boel.
There is nothing excluding you from having two diagnoses, and believe me stranger things have happened.
I haven't been following your threads, so am not up on all your symptoms. However, even on a preexisting diagnosis of AS a new red hot monoarthritis (ie single joint) bears some consideration. The differential diagnosis for such a list is longer than just 'gout' as well. There's gout, pseudogout, septic/infective arthritis, reactive arthritis, etc. I've even seen someone who was admitted ?monoarthritis who had a cellulitis. Medicine doesn't play by hard and fast rules.
To put an end to this once and for all you need someone to stick a needle in there and get a joint aspirate. The fluid can be sent for microscopy, cultura and sensitivity. They'll check for signs of infection (bacteria, white cells) and also look for crystals (different crystals for gout and pseudogout), and then you can plan the appropriate attack.
Good luck,
Jeanna
