Welcome to the forum

I am sorry about your concerns for your daughter's health. A positive ANA especially at a higher titre is an important clue in diagnosis of lupus. But it is not specific to lupus and many other tests can provide additional important information. There can be abnormalities in the complete blood count, low white cells or anemia for example. Then there is a wide range of more specialised blood tests for auto antibodies such as
anti ds- NA, or a protein called
complement which is often lower than normal, tests for possible clotting problems such as
lupus anticoagulant and
anti cardiolipins, in fact all the usual tests that adults should get, including urine and kidney and liver functions.
You can find information about diagnosis & testing here
http://www.uklupus.co.uk/
There is a wealth of information available here so do not hesitate to ask for help. It is important that you know about lupus as you are your child's advocate and need to dialogue with the doctors on her behalf. There is an overwhelming amount of information so take it step by step. Ask for copies of all test results and learn to understand them and what they might mean - we can help you with that. This way you can little by little familiarise yourself with the terms. You can make sure all the right tests are being done and ask the doctors questions.
We will help you all we can.
Bye for now
Clare