Can Auto Immune Disorder Cause Severe Outbreak Of Hives?

Hi i having been having hives for the past few months just randomly then a few weeks ago i had quite a bad attack ended up on steriods and 2 lots of antihistamines, i have just been told that a blood sample taken for esterase has come back high 264 can you tell me what this means i was sent to a dermatolgist who basically said there is nothing than can be done other than giving me an epi pen and 3 lots of antihistmaines, he did say that it could be linked to an auto immune disorder but that would require further tests,Im worried, can you help