Acute syphilitic interstitial orchitis mimicking testicular malignancy in an HIV-1 infected man diagnosed by Treponema pallidum polymerase chain reaction

We report a case of acute epididymo-orchitis due to early infectious syphilis, mimicking as testicular malignancy in an undiagnosed HIV-positive individual. He presented with a mass on his testicle and simultaneously had serology consistent with early syphilis. It could not be distinguished from a malignancy, which necessitated urgent orchidectomy. Histology showed endarteritis but no evidence of gummatous involvement. Although treponemes were not detected by staining, the diagnosis was confirmed by the first reported use of Treponema pallidum polymerase chain reaction in a testicular specimen in the UK.