Chronic syphilitic polyarthritis mimicking systemic lupus erythematosus/rheumatoid arthritis as the initial presentation of human immunodeficiency virus infection.

Syphilitic arthritis has been well characterized but not previously described as the initial presentation of human immunodeficiency virus (HIV) infection. Our patient presented with chronic symmetric polyarthritis and autoimmune abnormalities, including positive rheumatoid factor, antinuclear antibody, dsDNA, and initially negative syphilis serologies. Subsequent investigations revealed HIV seropositivity, depletion of CD4 cells, and strongly positive syphilis serologies. Our patient's arthritis completely resolved with penicillin therapy.