yes you can but since crohn's and lupus are both autoimmune sometimes Lupus comes up as a false positive. When I have had bad flares I have come up positive for Lupus but it was a false positive. Once you have one autoimmune issues the rest become much more likely which is why a lot people on this forum have skin, joint, eye, ect... problems.
my false positives have freaked me out but i have been resured by my rhyme this happens a lot. Good luck!