“Why do I get hot and itchy?”

Hi I'm a 40 year old male 5'9" 170 lbs. I have asthma and have irritable bowel syndrome as well as hiatal hernia. The problem I'm asking about is. I have always been one to get breakouts all over my body of itchy red spots when I am in contact with city water or pool water but lately, it has gotten worse I now break out from not do anything. I can just get up and go outside to the mailbox and come back in and I'll start feeling hot like I'm overheating thin I'll start to get red itchy spots all over me that will if I don't try to cool down right away will within 5 minutes be so bad the red spots turn into blister-like spots all over and very itchy and deep red. I have been tested for liver diseases and come up clear other than the blood work showed I'm liver enzymes are elevated every time I get blood work taken. They have had a liver biopsy, CT, MRI, x-rays and they do send a camera in me from both ends. Not finding anything. I don't know what to do or where to go to get an answer so I'm hoping I can get some info on here.