Hi Katie, welcome to the board. I am sorry to hear you are having such problems. The dx process can be very exhausting, unfortunaltey there is not one test to dx it so the doctor has to put the puzzle together one piece at a time. Plaquenil is not used with just lupus, do you have joint pain, etc? If so your doctor may suspect some sort of UCTD and that is how it's treated. What other kind of lupus symptoms do you have and for how long?
I was dx with lupus with a positive ANA, SED, SSA, low C3 & a ton of symptoms but it took a couple of years and a couple of rheumy's. I am not sure if lupus makes your potassium, etc low but I do know it can affect your WBC, RBC, etc.
I also have Hashi's and have never heard of the saliva testing. I was dx with the thyroid antibody test Rosie mentioned with a normal TSH, T3 & T4.
I sure hope you get some answers soon! Take care
Trust in the Lord with all thine heart, and lean not unto thine own understanding ~ Proverbs 3:5 ~
DX: Hashimoto's, Celiac Disease, Raynaud's, Lupus and Sjogrens
RX: Imuran, Plaquenil, Methotrexate, Flexeril, Piroxicam, Levoxyl, Folic Acid, Lortab (as needed) and magic mouthwash (for mouth sores)