I'm having the exact same thing going on . I saw a immunologist and he said he's certain I have it 

 I get the itchy skin everything . I have my byopsys tomorrow . Over past two days I've really not felt right at all I'm struggling to get out of bed ! I've never felt so weak and my whole body is aching but not sure if that's because I'm going in to a bad flare with my RA or if it's related to this  I've tried ringing go but she's not bk until tomorrow so I'm like should I see out of hours gp or just wait ? 

What tests did you have? Is your hospital visit tomorrow the 2nd time you've been in relation to this. Not sure what to say regarding out of hours gp or waiting sorry not much help there. Hope you go on ok though