First, Lupus is diagnosed by a rheumatologist, not by a primary care doctor. Second, Lupus is diagnosed by a collection of symptoms, not just by blood tests. A patient can easily be diagnosed by a preponderance of symptoms in the absence of blood tests.
Since you are suspecting Lupus, I would suggest an appointment with a rheumatologist to get a workup!
Typically, four or more of the following eleven criteria must be present to make a diagnosis of Systemic Lupus.
1. Malar rash: butterfly-shaped rash across cheeks and nose
2. Discoid (skin) rash: raised red patches
3. Photosensitivity: skin rash as result of unusual reaction to sunlight
4. Mouth or nose ulcers: usually painless
5. Arthritis (non-erosive) in two or more joints, along with tenderness, swelling, or effusion. With non-erosive arthritis, the bones around joints don’t get destroyed.
6. Cardio-pulmonary involvement: inflammation of the lining around the heart (pericarditis) and/or lungs (pleuritis)
7. Neurological disorder: seizures and/or psychosis
8. Renal (kidney) disorder: excessive protein in the urine, or cellular casts in the urine
9. Hematologic (blood) disorder: hemolytic anemia, low white blood cell count, or low platelet count
10. Immunologic disorder: antibodies to double stranded DNA, antibodies to Sm, or antibodies to cardiolipin
11. Antinuclear antibodies (ANA): a positive test in the absence of drugs known to induce it.
Lynnwood, Lupus & Sjogren's Moderator, Dx: 2000DIAGNOSING LUPUS & HW's LUPUS 101
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