Rheumatologic Tests: A Primer for Family Physicians

AAFP clinical review giving family physicians a framework for serologic testing in suspected connective tissue disease. It states ANA is the hallmark of SLE (present in >95% of SLE patients) but that most ANA-positive patients do not have SLE, and directs follow-up testing by suspected disease. Candidate notes: ANA by indirect immunofluorescence: sensitivity 93%, specificity 57% for SLE; by ELISA: sensitivity 81.9%, specificity 79.6% Once a patient has a positive ANA titer, it is rarely helpful to repeat the test; ANA levels fluctuate and do not reflect disease activity Pattern-disease associations: homogeneous or rim pattern in SLE; speckled in Sjogren syndrome; nucleolar in scleroderma; centromere pattern in limited scleroderma (CREST) Limits noted in the record: Primer-style review summarizing test characteristics from cited studies, not a formal systematic guideline with graded recommendations Reported test performance varies by assay manufacturer and patient population A positive ANA is not a diagnosis. Claims in this record are not verified.

A positive ANA is not a diagnosis. Claims in this record are not verified.

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