Human immunodeficiency virus (HIV) infection may lead to both false-negative and false-positive results on serologic tests for syphilis, hampering the accurate diagnosis of syphilis in patients with HIV. We describe 2 HIV-infected patients in whom there was no history or signs and symptoms of syphilis. One had negative results on syphilis screening tests but positive results on confirmatory tests; the other had positive screening test results but negative results on confirmatory tests. In both patients, polymerase chain reaction (PCR) analysis for Treponema pallidum DNA using specimens of separated peripheral blood mononuclear cells and serum1 confirmed the presence of syphilis.
Kuznetsov AV, Burgdorf WHC, Prinz JC. Latent Syphilis Confirmed by Polymerase Chain Reaction in 2 HIV-Positive Patients With Inconclusive Serologic Test Results. Arch Dermatol. 2005;141(9):1169-1170. doi:10.1001/archderm.141.9.1169