title: Accuracy of a rapid real-time polymerase chain reaction assay for diagnosis of group B Streptococcus colonization in a cohort of HIV-infected pregnant women.
abstract: OBJECTIVE
  There are limited data regarding Xpert performance to detect Group B Streptococcus (GBS) in HIV-infected pregnant women. We evaluated the accuracy of a rapid real-time polymerase chain reaction (PCR) test in a cohort of HIV-infected women.
  
  
  METHODS
  At 35-37 weeks of pregnancy, a pair of combined rectovaginal swabs were collected for two GBS assays in a cohort of sequentially included HIV-infected women in Rio de Janeiro: (1) culture; and (2) real-time PCR assay [GeneXpert GBS (Cepheid, Sunnyvale, CA)]. Using culture as the reference, sensitivity, specificity, positive and negative-likelihood ratios were estimated.
  
  
  RESULTS
  From June 2012 to February 2015, 337 pregnant women met inclusion criteria. One woman was later excluded, due to failure to obtain a result in the index test; 336 were included in the analyses. The GBS colonization rate was 19.04%. Sensitivity and specificity of the GeneXpert GBS assay were 85.94% (95% CI: 75.38-92.42) and 94.85% (95% CI: 91.55-96.91), respectively. Positive and negative predictive values were 79.71% (95% CI: 68.78-87.51) and 96.63% (95% CI: 93.72-98.22), respectively.
  
  
  CONCLUSIONS
  GeneXpert GBS is an acceptable test for the identification of GBS colonization in HIV-infected pregnant women and represents a reasonable option to detect GBS colonization in settings where culture is not feasible.
authors.affiliation: a Infectious Diseases Department, Hospital Federal dos Servidores do Estado , Rio de Janeiro , Brazil.|b Instituto Nacional de Infectologia Evandro Chagas - Fiocruz , Rio de Janeiro , Brazil.
authors.forename: Maria Isabel S
authors.initials: MIS
authors.lastname: Gouvea
authors.affiliation: a Infectious Diseases Department, Hospital Federal dos Servidores do Estado , Rio de Janeiro , Brazil.
authors.forename: Esau C
authors.initials: EC
authors.lastname: Joao
authors.affiliation: a Infectious Diseases Department, Hospital Federal dos Servidores do Estado , Rio de Janeiro , Brazil.|b Instituto Nacional de Infectologia Evandro Chagas - Fiocruz , Rio de Janeiro , Brazil.
authors.forename: Maria de Lourdes B
authors.initials: MLB
authors.lastname: Teixeira
authors.affiliation: c Department of Epidemiology and Biostatistics , University of California at San Francisco , San Francisco , CA , USA.
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Read
authors.affiliation: d Laboratório de Bacteriologia Médica do Instituto de Microbiologia Prof. Paulo de Góes , Universidade Federal do Rio de Janeiro , Rio de Janeiro , Brazil.
authors.forename: Sergio E L
authors.initials: SEL
authors.lastname: Fracalanzza
authors.affiliation: b Instituto Nacional de Infectologia Evandro Chagas - Fiocruz , Rio de Janeiro , Brazil.
authors.forename: Claudia T V
authors.initials: CTV
authors.lastname: Souza
authors.affiliation: e Department of Bacteriology , Hospital Federal dos Servidores do Estado , Rio de Janeiro , Brazil , and.
authors.forename: Maria José de
authors.initials: MJ
authors.lastname: Souza
authors.affiliation: f Laboratório Richet , Núcleo de Apoio à Pesquisa Clínica , Rio de Janeiro , Brazil.
authors.forename: Helio M
authors.initials: HM
authors.lastname: Torres Filho
authors.affiliation: f Laboratório Richet , Núcleo de Apoio à Pesquisa Clínica , Rio de Janeiro , Brazil.
authors.forename: Cassiana C F
authors.initials: CCF
authors.lastname: Leite
authors.affiliation: b Instituto Nacional de Infectologia Evandro Chagas - Fiocruz , Rio de Janeiro , Brazil.
authors.forename: Pedro E A A
authors.initials: PEAA
authors.lastname: do Brasil
mesh_terms: D000328:Adult; D005260:Female; D015658:HIV Infections / Q000150:complications; D006801:Humans; D018445:Infectious Disease Transmission, Vertical; D008403:Mass Screening / Q000191:economics / Q000379:methods; D011237:Predictive Value of Tests; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000175:diagnosis* / Q000382:microbiology; D011446:Prospective Studies; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods*; D013290:Streptococcal Infections / Q000150:complications / Q000175:diagnosis*; D013292:Streptococcus agalactiae / Q000235:genetics / Q000302:isolation & purification*; D013997:Time Factors; D014621:Vagina / Q000382:microbiology; D019562:Viral Load / Q000706:statistics & numerical data; D055815:Young Adult
keywords: Culture; HIV; group B Streptococcus; real-time polymerase chain reaction