Clinical Review & Education
JAMA Diagnostic Test Interpretation
Clinical Significance of a Positive Antinuclear Antibody Test Gita Fatemi, MD; Tanaz A. Kermani, MD, MS
A 30-year-old woman presented to the rheumatology clinic after experiencing 2 months of fatigue and polyarthralgias of the wrists, hands, knees, and feet. She reported no joint swelling or morning stiffness. She previously saw her primary care physician who prescribed celecoxib (for joint pain) and ordered antinuclear antibody (ANA) testing, which was positive at a value of 1:80 (Table). She was then referred to the rheumatology clinic. The patient reported no history of fever, weight loss, photosensitivity, malar rashes, skin thickening, oral or nasal ulcers, weakness, Raynaud phenomenon, sicca symptoms, chest pain, shortness of breath, or abdominal pain. She was not taking any medications because 2 weeks after starting celecoxib, her joint pain resolved and she discontinued use without recurrence of pain. The patient had no family history of autoimmune diseases. On examination, her vital signs, including blood pressure, were normal; and results of skin, thyroid, musculoskeletal, mucus membranes, cardiovascular,pulmonary,andneurologicexaminationswereallnormal.Additionaltestresults,which were obtained after her rheumatology visit, are presented in the Table. Table. Clinic Laboratory Values Laboratory Test
Patient’s Values
Reference Ranges
Antinuclear antibody, titer
1:80 Homogenous and speckled