I'd be a little concerned of having hepatitis too with those test results. Have they ruled out a liver problem? An ANA can go negative when your taking plaquenil, that happened to me once, and because of, I was told I could not have an autoimmune disease, and that it was just fibromyalgia. 10 1/2 yrs later of repeated tests show my ana is 1:640 now and RNP is pretty high. All my past tests, my ANA was high, except that one after I took plaquenil. It was always the same, 1:320.
I don't have trouble getting over a cold so bad, the trouble is that it just drags me down harder because I'm tired anyways. I don't get sick alot. Your immune system can weeken even if it is overactive. I'd say you have a better chance of that if your taking antibiotics regularly or immunosuppressive medications, plaquenil will not cause that. Maybe ask your doctor if a low dose of vitamin c would be safe.
If you drink a bottle of grapefruit juice down pretty fast, it can help a bronchitis infection. Moonshine will clear up a sinus infection right now, so I've heard. lol..