I Have Red Sores On My Arms And Have Had

I have red sores on my arms and have had them for five years. My cousin is an RN and she took one look and said she'd had similar ones and that after eight years she was diagnosed with cutaneous lupus. I have seen dermatologist and my primary doctor. My primary doctor is finally doing an ANA Panel. My arms itch under the skin and on top constantly. Will this show up in a blood test?