A 23 yr. old female came with arthritis, Malar rash, oral ulcers, serositis (pleuritis or pericarditis). The likely investigation to be positive is
Anti nuclear antibody
Anti collagen antibody
Anti epithelial antibody
Antigen antibody complexes
(A) Anti nuclear antibody # Antinuclear antibody (ANA) tests are positive in 5 to 10 percent of the general population, a rate that increases with age.> Thus, given a one in 20 frequency for ANAs and a one in 2,000 frequency for systemic lupus erythematosus, only one in 100 persons with a positive ANA test will have the disease.> Consequently, positive ANA test results must be interpreted with caution.> Given the high sensitivity of the currently used substrate for testing, a negative ANA test essentially rules out systemic lupus erythematosus.
Miscellaneous