title: Detection of Treponema pallidum Sp. Pallidum DNA in Cerebrospinal Fluid (CSF) by Two PCR Techniques.
abstract: BACKGROUND
  Laboratory diagnosis of neurosyphilis is complicated especially when it is asymptomatic, no single laboratory test result being appropriate to diagnose central nervous system infectivity caused by Treponema pallidum. Our objective was to evaluate two polymerase chain reaction (PCR) techniques for the detection of T. pallidum DNA in the cerebrospinal fluid (CSF) of patients with syphilis.
  
  
  METHODS
  One hundred twenty-four CSF samples from patients with reactive blood tests for syphilis were obtained. Two PCR techniques (47-PCR, polA-PCR) were used to detect T. pallidum DNA. The laboratory criteria used for the diagnosis of neurosyphilis to which the PCR techniques were compared were those recommended by the IUSTI: 2008 European guidelines on the management of syphilis.
  
  
  RESULTS
  Treponema pallidum DNA was detected amplified in 37 of 124 (29.8%) and 30 of 124 (24.2%) samples with the 47-PCR and polA-PCR, respectively. Sensitivities were 75.8% and 69.7% and specificities 86.8% and 92.3%, respectively, for 47-PCR and polA-PCR techniques, respectively. The three CSF samples of patients with primary syphilis did not fulfill the criteria of neurosyphilis and DNA was only detected in one by the 47-PCR. In samples from secondary syphilis and neurosyphilis, three of nine and nine of nine respectively, results were coincident for the two PCR techniques and neurosyphilis criteria. Major discrepancies between the two PCR techniques and neurosyphilis diagnostic criteria were observed in latent syphilis.
  
  
  CONCLUSIONS
  Beyond some limitations of the study, which are discussed here, both PCR techniques seem to be useful for the diagnosis of neurosyphilis, although 47-PCR presents a higher sensitivity and polA-PCR a higher specificity.
authors.affiliation: Instituto de Higiene e Medicina Tropical, Unidade de Microbiologia Médica, Lisboa, Portugal. ritacastro@ihmt.unl.pt.
authors.forename: Rita
authors.initials: R
authors.lastname: Castro
authors.affiliation: Serviço de Infecciologia, Hospital Garcia de Orta, Lisboa, Portugal.
authors.forename: Maria João
authors.initials: MJ
authors.lastname: Águas
authors.affiliation: Serviço de Infecciologia e Medicina Tropical, Hospital de Egas Moniz (Centro Hospitalar de Lisboa Ocidental), Lisboa, Portugal.
authors.forename: Teresa
authors.initials: T
authors.lastname: Batista
authors.affiliation: Serviço de Infecciologia e Medicina Tropical, Hospital de Egas Moniz (Centro Hospitalar de Lisboa Ocidental), Lisboa, Portugal.
authors.forename: Carlos
authors.initials: C
authors.lastname: Araújo
authors.affiliation: Serviço de Infecciologia e Medicina Tropical, Hospital de Egas Moniz (Centro Hospitalar de Lisboa Ocidental), Lisboa, Portugal.
authors.forename: Kamal
authors.initials: K
authors.lastname: Mansinho
authors.affiliation: Instituto de Higiene e Medicina Tropical, Unidade de Clínica Tropical, Lisboa, Portugal.
authors.forename: Filomena da Luz Martins
authors.initials: Fda L
authors.lastname: Pereira
mesh_terms: D000328:Adult; D016054:DNA, Protozoan / Q000134:cerebrospinal fluid*; D006801:Humans; D016133:Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D013587:Syphilis / Q000134:cerebrospinal fluid / Q000469:parasitology; D014210:Treponema pallidum / Q000235:genetics / Q000302:isolation & purification*
chemical_list: D016054:DNA, Protozoan
keywords: CNS infection; T. pallidum; neurosyphilis