Molecular detection of Treponema pallidum in secondary and tertiary syphilis

Abstract

Treponema pallidum can be detected by conventional techniques such as dark-field microscopy, immunofluorescence or the rabbit infectivity test, in large numbers in the skin lesions of primary and early secondary syphilis. In the skin lesions of late secondary and tertiary syphilis, conventional techniques fail to detect spirochaetes in general, perhaps due to increasing degeneration and the disappearance of treponemal spirochaetes in late syphilitic skin lesions. We used the highly sensitive technique of polymerase chain reaction (PCR) to prove the presence of Treponema pallidum-specific DNA in six lesions of late secondary syphilis and seven lesions of tertiary syphilis, including one syphilitic gumma. A Whartin-Starry stain was carried out in all 13 specimens and did not reveal any treponemal structures. Treponema pallidum-specific DNA was amplified by PCR in four of six cases of secondary syphilis and in the syphilitic gumma. These results are in favour of a direct cell-mediated immune reaction directed against treponemal antigen rather than the concept of an Id-reaction. Beside the usefulness of a PCR-based assay for understanding the aetiology of lesions of late syphilis, the assay described can be of clinical importance in various situations where traditional methods fail to detect Treponema pallidum because of lack of sensitivity.

Detection of <i>Treponema pallidum</i> in Skin Lesions of Secondary Syphilis and Characterization of the Inflammatory Infiltrate

“…The recent advent of PCR technology and the completion of the genome sequence of T. pallidum have greatly advanced our detection ability, providing an opportunity for better understanding the pathogenesis of secondary syphilis. There are, however, few studies that have analyzed the presence of T. pallidum DNA in skin lesions of secondary syphilis [7, 8]. In this report, we designed a highly sensitive nested PCR method with two pairs of primers to detect the T. pallidum genome.…”

Syphilis in pregnancy

“…However, failure to find the organism does not exclude a diagnosis of syphilis. False negative results occur because of the age and condition of the lesion, 35 treatment of the patients with antibiotics systemically or locally before the specimen collected and, most commonly, poor technique in collecting and reading the specimen. 36 Serological tests for syphilis are classified into non-treponemal tests which include the venereal disease research laboratory (VDRL) and rapid plasma reagin (RPR) tests; and the treponemal tests, which include the fluorescent treponemal antibody absorption (FTA-ABS) assay and the microhaemagglutination assay for T pallidum antibody (MHA-TP).…”

“…57 PCR was used to detect T pallidum DNA in the amniotic fluid collected early in the second trimester and was shown to be both sensitive and specific when compared with recovery of spirochaetes with rabbit infectivity test. 35 Ultrasonography was used to detect some of the manifestations of syphilis in the fetus such as hydrops fetalis characterised by scalp oedema, placental thickening, serous cavity eVusion, and polyhydramnios. 58 Other ultrasonographic findings related to fetal syphilis include hepatosplenomegaly, placentomegaly, non-continuous gastrointestinal obstruction, and dilatation of the small bowel.…”

Bekanntmachung des Arbeitskreises Blut des Bundesministeriums für Gesundheit¶Treponema pallidum

“…Nukleinsäure-Amplifikationsverfahren wie die PCR können T. pallidum ssp. pallidum aus Blut, Liquor, Urin sowie Amnionflüssigkeit nachweisen [35,36,37,38,39,40,41], jedoch besteht noch keine Klarheit über die Indikationen für ihren Einsatz in der Syphilisdiagnostik [23].…”