title: Alternative cerebrospinal fluid tests to diagnose neurosyphilis in HIV-infected individuals.
abstract: OBJECTIVE
  To identify alternatives to the CSF-Venereal Disease Research Laboratory (VDRL) test for the diagnosis of neurosyphilis in HIV-infected individuals.
  
  
  METHODS
  CSF fluorescent treponemal antibody (FTA) reactivity and % CSF lymphocytes that were B cells in fresh and frozen samples were determined for 47 HIV-infected cases with syphilis and 26 HIV-infected controls. As for serum, CSF fluorescent treponemal antibody reactivity > or =2+ was considered positive. Based on the results in controls and cases with normal CSF measures, cut-offs for elevated CSF B cells were proposed to be > or =9% in fresh and > or =20% in frozen samples. Neurosyphilis was defined as a reactive CSF-VDRL.
  
  
  RESULTS
  CSF-FTA-ABS (absorbed) and CSF-FTA (unabsorbed and undiluted) were 100% sensitive for the diagnosis of neurosyphilis. Elevated % CSF B cells in fresh and cryopreserved samples was specific (100%) but not sensitive (40 and 43%) in post hoc analyses. The results of CSF-FTA and assessment of % CSF B cells together allowed 16% of cases with pleocytosis but nonreactive CSF-VDRL to be diagnosed with neurosyphilis and 26% to be diagnosed as not having neurosyphilis.
  
  
  CONCLUSIONS
  When the CSF-VDRL is nonreactive, CSF-FTA and % CSF B cells may help exclude or establish the diagnosis of neurosyphilis.
authors.affiliation: Department of Neurology, University of Washington School of Medicine, Seattle, USA. cmarra@u.washington.edu
authors.forename: C M
authors.initials: CM
authors.lastname: Marra
authors.forename: L C
authors.initials: LC
authors.lastname: Tantalo
authors.forename: C L
authors.initials: CL
authors.lastname: Maxwell
authors.forename: K
authors.initials: K
authors.lastname: Dougherty
authors.forename: B
authors.initials: B
authors.lastname: Wood
mesh_terms: D000042:Absorption; D000328:Adult; D000818:Animals; D000913:Antibodies, Protozoan / Q000276:immunology*; D001402:B-Lymphocytes; D002308:Cardiolipins / Q000134:cerebrospinal fluid* / Q000276:immunology; D002555:Cerebrospinal Fluid / Q000166:cytology; D002784:Cholesterol / Q000134:cerebrospinal fluid* / Q000276:immunology; D005188:False Negative Reactions; D005260:Female; D005434:Flow Cytometry; D019084:Fluorescent Antibody Technique, Indirect; D015658:HIV Infections / Q000150:complications*; D006801:Humans; D007964:Leukocytosis / Q000134:cerebrospinal fluid / Q000209:etiology; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D009494:Neurosyphilis / Q000134:cerebrospinal fluid* / Q000150:complications / Q000175:diagnosis; D010713:Phosphatidylcholines / Q000134:cerebrospinal fluid* / Q000276:immunology; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D013588:Syphilis Serodiagnosis / Q000379:methods*; D014210:Treponema pallidum / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D002308:Cardiolipins; D010713:Phosphatidylcholines; C054448:VDRL antigen; D002784:Cholesterol