title: [Chlamydia trachomaatis DNA in leukocytes of peripheral blood from neonates].
abstract: BACKGROUND
  Diagnosis of Chlamydia trachomatis infection in newborns is difficult; however, this diagnosis is performed by cell culture or by detection of IgM antibodies against C. trachomatis. Detection of C. trachomatis DNA in peripheral blood leukocytes using polymer chain reaction (PCR) may be a better tool for the diagnosis of infection by this pathogen.
  
  
  METHODS
  A total of 44 premature newborns, all weighing less than 2500g, were included in the study. A blood sample and nasopharyngeal lavages were obtained from each newborn. Leukocyte DNA was obtained by phenol-chloroform extraction technique. Detection of C. trachomatis was performed by amplifying the ompA gene using the PCR endpoint. Cell culture tests and the detection of IgM antibodies against C. trachomatis by microimmunofluorescence assay were also performed.
  
  
  RESULTS
  Twenty newborns were PCR-positive (45.5%), with this test being significantly associated with the presence of pneumonia (RR=2.28; 95%CI: 1.01 to 5.17; P=.035). The cell culture of nasopharyngeal lavage was positive in only 7 samples and no significant association was observed with any clinical or laboratory data. The titer of IgM antibodies against C. trachomatis associated with PCR-positive was 1:32 (RR=2.74; 95%CI: 1.21 to 6.23; P=.008), however this titer was not associated with the presence of pneumonia.
  
  
  CONCLUSIONS
  DNA detection in peripheral blood leukocytes could be useful for diagnosis of C. trachomatis infection.
authors.affiliation: Laboratorio de Virología, Instituto Nacional de Perinatología, México D.F., México; Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, México D.F., México.
authors.forename: Marcela
authors.initials: M
authors.lastname: López-Hurtado
authors.affiliation: Laboratorio de Virología, Instituto Nacional de Perinatología, México D.F., México; Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, México D.F., México.
authors.forename: Karla N
authors.initials: KN
authors.lastname: Cuevas-Recillas
authors.affiliation: Laboratorio de Virología, Instituto Nacional de Perinatología, México D.F., México; Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, México D.F., México.
authors.forename: Verónica R
authors.initials: VR
authors.lastname: Flores-Salazar
authors.affiliation: Laboratorio de Virología, Instituto Nacional de Perinatología, México D.F., México; Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas, México D.F., México. Electronic address: fguerra_96@yahoo.com.
authors.forename: Fernando M
authors.initials: FM
authors.lastname: Guerra-Infante
mesh_terms: D000907:Antibodies, Bacterial / Q000097:blood; D016470:Bacteremia / Q000097:blood* / Q000175:diagnosis / Q000382:microbiology; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics; D001724:Birth Weight; D002692:Chlamydia trachomatis / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D061387:Chlamydial Pneumonia / Q000097:blood* / Q000175:diagnosis / Q000382:microbiology; D060085:Coinfection; D004269:DNA, Bacterial / Q000097:blood*; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007231:Infant, Newborn / Q000097:blood*; D007234:Infant, Premature / Q000097:blood*; D007235:Infant, Premature, Diseases / Q000097:blood* / Q000175:diagnosis / Q000382:microbiology; D007962:Leukocytes / Q000382:microbiology*; D008297:Male; D009175:Mycoplasma Infections / Q000097:blood / Q000453:epidemiology; D009305:Nasopharynx / Q000382:microbiology; D016133:Polymerase Chain Reaction / Q000379:methods; D007507:Therapeutic Irrigation
chemical_list: D000907:Antibodies, Bacterial; D001425:Bacterial Outer Membrane Proteins; D004269:DNA, Bacterial; D007075:Immunoglobulin M; C078167:OMPA outer membrane proteins
keywords: Blood; Chlamydia trachomatis; Gen ompA; Neonates; Neonatos; Neumonía; Pneumonia; Polymer chain reaction; Reacción en cadena de la polimerasa; Sangre; ompA gene