Hi again Andrea,
I also had weight loss along with incredible hunger. I would eat and eat but still lose weight and feel hungry as soon as I'd finished eating!! Happily I have regained the pounds I'd lost after 2 years. I still feel hungry but not as much as before.
I also had small intestinal bacterial overgrowth which was adding to my histamine levels and causing malabsorption. I was given a hydrogen breath test which confirmed the SIBO. I'll try and find the case you mentioned on Pub med.
I understand how scared you feel with the reactions. They are definitely unpredictable and it's sometimes difficult to ascertain what caused them when you're trying to be careful with your diet.
Like you I'm allergic to mould and yeast. In the autumn my symptoms would worsen with the mould spores and in the sring/summer pollen would set them off! The pollen allergy has been better this year since taking magnesium.
Enzymes have helped me too. I read "Enzymes:Go with your Gut" by Karen DeFelice (American) which explained wonderfully how an injured gut could cause food intolerance (injured by the bacteria). She does say that dairy may provoke histamine release but I drink milk for the calories!
Amylase is an antihistamine.
Dr Ellen Cutler developed "Bioset" enzymes which are the only ones I tolerate. She is in California I believe and well worth investigating at www.bioset.com
I went to Glasgow to the only Bioset Practitioner in the UK but could only afford one trip sadly as the doctor was excellent.
Hope was the only thing that kept me going and I still remain determined that I will beat this!
Do investigate Magnesium, Magnesium is needed to reduce histamine levels. I read "Magnesium deficiency has been shown to increase degranulation of mast cells and to increase histamine blood and urinary levels" and "Mag deficiency has been implicated in allergies and allergic skin reactions"