If your Lupus has prevented you from working a job and is serious enough and you can prove it then you'll usually be approved for the disability when having lupus within 90 days.
You'll likely have to get a disability lawyer that helps with getting SSI Disability payments to fight for your disability payments in court.
Sometimes it might take a few tries to get the disability payments approved when you have Lupus or any other ailments that prevent you from working a job.
So don't give up if you're denied the first time and keep trying because sometimes it takes even a few years to win a case for disability payments and few more tries.
Just make sure you have your doctors papers and diagnoses in place with you when you go into court to fight for disability.