Hi!
I am not sure what ANA <1 means. Usually it is represented as 1:40, 1:80, 1:360 etc. Any test which detects ANA in dilution more than 1:40 is considered positive. Other antibodies are in normal range. Sjogren's, scleroderma and other mixed connective tissue disorders are ruled out. To establish a diagnosis of lupus, dsDNA antibody should be positive. Positive ANA is also an indication of lupus.
The American College of Rheumatology (ACR) has identified 11 characteristics that should be present for diagnosis of SLE or lupus and it is important that at least 4 of the characteristics should be present for a confirmed diagnosis. This includes serositis (pleurisy or pericardiatis, ask your doctor to check for pleurisy or inflammation of lining of lung), mouth ulcer, low WBC or leucopenia/anemia (hemolytic)/thrombocytopenia/lymphopenia, arthritis, kidney involvement, high ANA, finding of Smith Antibody (Anti-Smith)/ dsDNA/ antiphospholipid antibodies (anticardiolipin immunoglobulin G [IgG] or immunoglobulin M [IgM] or lupus anticoagulant), neurological features like seizures and psychosis, discoid rash and malar rash. Do discuss this with your doctor and get yourself examined. Take care!