title: Diagnosing Treponema pallidum in secondary syphilis by PCR and immunohistochemistry.
abstract: Epidemiological aspects of syphilis in Western countries have undergone a significant change with respect to the number of cases. Detection of Treponema pallidum is difficult, and the correct diagnosis of secondary syphilis can be critical. In this study, biopsy samples from skin lesions of 12 patients with secondary syphilis were used. Diagnosis of syphilis was based on clinical presentation, dark-field microscope analysis, and serological tests. Using a polyclonal antibody directed against T. pallidum, we show the presence of T. pallidum in 90% of the samples studied with the bacteria located in the epidermis and the upper dermis. The T. pallidum 47-kDa surface protein gene could be amplified by PCR in 75% of the skin lesions. When combining both techniques, T. pallidum was detected in 92% of the samples from patients with secondary syphilis but not in the control samples. Our work suggests that both immunohistochemistry and PCR could be useful for the diagnosis of secondary syphilis and may be helpful in some rare cases when serological assays failed to detect T. pallidum antibodies.
authors.affiliation: UPRES-EA1833 Laboratoire de Recherche en Dermatologie, Centre National de Référence Syphilis, Paris, France.
authors.forename: Marc
authors.initials: M
authors.lastname: Buffet
authors.forename: Philippe A
authors.initials: PA
authors.lastname: Grange
authors.forename: Philippe
authors.initials: P
authors.lastname: Gerhardt
authors.forename: Agnès
authors.initials: A
authors.lastname: Carlotti
authors.forename: Vincent
authors.initials: V
authors.lastname: Calvez
authors.forename: Anne
authors.initials: A
authors.lastname: Bianchi
authors.forename: Nicolas
authors.initials: N
authors.lastname: Dupin
mesh_terms: D000328:Adult; D000595:Amino Acid Sequence; D000907:Antibodies, Bacterial / Q000276:immunology / Q000378:metabolism; D001483:Base Sequence; D001706:Biopsy; D002352:Carrier Proteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D004269:DNA, Bacterial / Q000235:genetics; D005260:Female; D006801:Humans; D007150:Immunohistochemistry / Q000379:methods*; D008074:Lipoproteins / Q000032:analysis / Q000235:genetics / Q000378:metabolism; D008297:Male; D008969:Molecular Sequence Data; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D012867:Skin / Q000378:metabolism / Q000382:microbiology / Q000473:pathology; D013587:Syphilis / Q000175:diagnosis* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D014210:Treponema pallidum / Q000235:genetics* / Q000276:immunology* / Q000378:metabolism
chemical_list: C090573:47-kDa immunogen, Treponema pallidum; D000907:Antibodies, Bacterial; D002352:Carrier Proteins; D004269:DNA, Bacterial; D008074:Lipoproteins