In systemic lupus erythematosus, which autoantibody titer correlates with disease activity?

• A. dsDNA
• B. SSA
• C. Sm
• D. RF

Answer: (A)

Anti-double-stranded DNA antibodies track lupus disease activity. When SLE flares occur, the titers of anti-dsDNA often rise, and they tend to decrease during remission. This pattern is especially evident with kidney involvement, where immune complex formation with dsDNA contributes to nephritis, so the titer tends to parallel clinical activity and complement consumption (C3/C4) may drop as activity increases. Because of this direct association with ongoing inflammatory activity and organ involvement, anti-dsDNA levels are routinely used to monitor disease course and response to therapy.

Antibodies to SSA (Ro) are common in SLE and Sjögren’s syndrome but do not reliably reflect fluctuation in disease activity. Antibodies to Sm are highly specific for SLE but their presence does not correlate well with how active the disease is. RF can be seen in various diseases and is not a reliable indicator of SLE activity.