welcome to healthcaremagic forum
SLE is multi system disease and can involve any organ of body .
gall stone is common in sle pt
she has symptomatic gall stone means she need surgery for that
there are two option
1-to remove stone only
2- to remove gall bladder
better option will be advise gastro surgeon
better to consult him .
surgery is safe to be done on her.so dont worry about it
i hope i have answered your question.