There are many other things that present with a positive ANA besides Lupus, so don't use the Internet to choose a diagnosis! Make sure your daughter sees a good pediatric rheumatologist
- these are the Drs that specialize in most of the diseases that include a positive ANA.
I don't know where you saw that the prognosis is poorer with early diagnosis - I've been a Lupus patient for over 15 years and never heard that. There is no "staging process" - Lupus is NOT a progressive disease, so one cannot definitively say it goes from one stage to the next.
Think of Lupus as an overactive immune system, a raging fire. Some days it might decide that the kidneys are foreign objects and attack them. A year later the kidneys might be fine and Lupus will decide to attack the toe joints and make them feel like burning acid has been injected into them. Lupus takes as many forms as there are patients, no 2 cases are ever alike.
Besides finding a Dr that will work with you for diagnosis and treatment, the basics are the same as for almost any disease. Healthy food, good hydration, regular moderate exercise, deep restorative sleep, avoid the sun, heat & fluorescent lights.
Do NOT take any supplements that say they "support the immune system" -- at least not unless a Dr tells you to. If it is Lupus, the immune system is already overactive, it doesn't need any support. Some people find that avoiding inflammatory foods is slightly helpful - I personally haven't been able to detect any differences here. (Although I do feel better on less sugar & less carbs, with more fiber & protein -- which is characteristic of any healthy diet.)
Let us know if we can help with any specific questions you may have!
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
"Life is far too important to be taken seriously." - Oscar Wilde