title: Comparison of nested polymerase chain reaction (PCR), real-time PCR and viral culture for the detection of cytomegalovirus in subgingival samples.
abstract: BACKGROUND
  The purpose of this study was to compare nested polymerase chain reaction (PCR), real-time PCR, and shell vial for the detection of human cytomegalovirus (HCMV) in subgingival samples in periodontitis patients.
  
  
  METHODS
  A group of 44 patients and 24 individuals without periodontitis were included in the study. A full periodontal examination was conducted in each subject. Gingival crevicular fluid (GCF) was collected by pocket lavage and used for viral culture (shell vial). Additional subgingival samples were obtained with paper points and used for molecular analysis. Nested PCR and real-time PCR were used to detect and quantify HCMV. Student's t-test and chi-squared test were used to compare groups. The sensitivity and specificity for the tests were calculated on 2 x 2 tables considering the nested PCR as the gold standard.
  
  
  RESULTS
  The detection of HCMV was greater using nested PCR than with either real-time PCR or shell vial (P < 0.0001). However, the frequency detection of both molecular techniques was higher than in viral culture (P < 0.0001). Only one case of chronic periodontitis was positive by viral culture. Agreement between nested PCR and real-time PCR was observed 47.7% and 4.1% of the time in the periodontitis and control groups, respectively. The sensitivity of real-time PCR was 60%, compared with 2.8% for the shell vial technique.
  
  
  CONCLUSIONS
  In conclusion, this study confirmed that active HCMV infection occurs in human periodontitis; however, its frequency seems to be low. In contrast, latent periodontal HCMV infection seems to be a more frequent event.
authors.affiliation: Periodontal Medicine Group, School of Dentistry, Universidad del Valle, Cali, Colombia. drjavo@yahoo.com
authors.forename: J E
authors.initials: JE
authors.lastname: Botero
authors.forename: C
authors.initials: C
authors.lastname: Vidal
authors.forename: A
authors.initials: A
authors.lastname: Contreras
authors.forename: B
authors.initials: B
authors.lastname: Parra
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000821:virology; D002478:Cells, Cultured; D002908:Chronic Disease; D003587:Cytomegalovirus / Q000302:isolation & purification*; D004279:DNA, Viral / Q000032:analysis; D003728:Dental Calculus / Q000821:virology; D003773:Dental Plaque / Q000821:virology; D005347:Fibroblasts / Q000821:virology; D005881:Gingiva / Q000166:cytology / Q000821:virology; D005883:Gingival Crevicular Fluid / Q000821:virology*; D005884:Gingival Hemorrhage / Q000821:virology; D006801:Humans; D017622:Periodontal Attachment Loss / Q000821:virology; D010514:Periodontal Pocket / Q000821:virology; D010518:Periodontitis / Q000821:virology*; D016133:Polymerase Chain Reaction; D011237:Predictive Value of Tests; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D014776:Virus Cultivation
chemical_list: D004279:DNA, Viral