Talk to Rheumatologist on Low Immunity

Aoa sir/ mam. My sister is a 23 years old student who has been a very active individual all her life mashaaallah except one time when she developed SLE at the age of 9 back in 2005-2006 she recieved proper treatment and was fully recovered by 2010. It affected her kidneys the most. Now after almost 10 years she felt pain in kidney . Her ultrasound of pelvis showed the cysts in right kidneys also soon after that she got sick two times and she felt so weak due to humdity in which she had excessive sweating . She feels fatigued low on energy all the time. I wanted to ask if these are the signs that sle is reoccurring ? Also how to boost up her immunity? And any diet and doctor suggestions. Please help me out here