Just wondering if anyone understands anything about what mechanism COULD be going on here.
This COULD be whats going on.
I think the overall itching is probably due to high histamine causing pruritus (skin itching) as its one of the possible symptoms of histamine overload and it doesn't normally leave a rash.
It seems there been a lot going on in your gut and high antibiotic use can cause gut dysbiosis and lead to damage to stomach lining villus and possible Coeliac disease (CD), even without symptomatic gluten symptoms.
http://www.medscape.com/viewarticle/809742_1
Coeliac can lead to a few of your other symptoms such as lung problems including asthma.
http://www.ncbi.nlm.nih.gov/pubmed/6101248?dopt=Abstract
http://www.medicalnewstoday.com/articles/248523.php
DAO is generated and stored in the gut and is dependent on an adequate supply of copper.
Fig. 5: Ribbon illustration of Diamine oxidase with copper-ions in both active centers. [
http://www.biology.leeds.ac.uk/centres/LIBA/cps/pherson.htm]
Coeliac causes copper deficiency which can cause low DAO and reduced lowering of histamine,
as well as a load of other symptoms.
http://glutenfreeworks.com/blog/201...-deficiency-in-celiac-disease/comment-page-1/
Copper is also required for absorption of iron. Copper deficiency can cause malabsorption of iron,
http://www.traceelements.com/Docs/The Nutritional Relationships of Copper.pdf
]Conditions Associated with Copper Imbalance
One of the earliest conditions found to be associated with copper deficiency is iron deficiency anemia, which could only be corrected with copper supplementation. Copper deficiency impairs iron absorption, reduces heme synthesis, and increases iron accumulation in storage tissues. These processes are dependent upon copper through the effects of the copper enzyme Ceruloplasmin.15 A chronic copper deficiency can result in hemosiderosis, a condition characterized by an increase in iron accumulation in body tissues due to an impairment in the reutilization of hemoglobin iron.
However, it is quite normal to have a low serum iron level when there are high bacterial infections.
Bacteria feeds on iron, so the body sequesters the iron in the spleen,liver and bones to defend itself which causes lower serum iron levels.
I think you might find it worthwhile to get a coeliac test and a copper/ceruloplasmin test from your doctor even if its just to rule out Coeliac. Unfortunately my experience of trying to get a copper test on the NHS was like trying to pull out lion's teeth. Research shows doctors will take on average 12 months of testing everything else,,before agreeing to a copper deficiency test and that's all doctors, not just NHS doctors.