the drs in uk dont give it a specific name either, they just call it autoimmune disorders. if you look it up on the web there are excellent sites about it.
if you have one auto you are at much higher risk of developing new ones. i have a thyroid disorder called graves disease, a clotting disorder called anti phosolipid antibodies, low platelets, and vitiligo, where you lose skin pigment. the good news is that they can spontaneously go into remission as well as appear. it is NOT lupus and is mainly found in women. our immune systems are confusing parts of ourselves with foreign bodies(like germs) and are attempting to kill them off. mostly they can control the symptons with prednisolone(a steroid) etc
good luck
low antibody level, something attacking body 
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