Did I read that right and yours as the same name! How strange!
Well I've searched about a bit and concluded it could be either an allergy or something to do with the immune system. Most often people have said it was an allergy so here's hoping. I've told mum dog food/treats only as she does have a tendancy to spoil her. And to check where she sleeps and the garden for anything different which could be bothering her.
Thank you for replying