title: Prospective clinical evaluation of the accuracy of 16S rRNA real-time PCR assay for the diagnosis of melioidosis.
abstract: The accuracy of a Burkholderia pseudomallei 16s rRNA real-time PCR assay was evaluated against culture for the diagnosis of melioidosis in Thailand. A total of 846 samples were obtained from 383 patients with suspected melioidosis. One or more specimens were PCR positive for 47 of 77 patients with culture-proven melioidosis (sensitivity 61.0%, 95% CI: 49.2-72.0%). PCR was negative for all 306 patients who were culture negative for B. pseudomallei (specificity 100%, 95% CI: 98.8-100%). Diagnostic sensitivity of PCR was 22.7% for patients who were culture positive for blood only, compared with 79.4% for patients who were culture positive for samples other than blood. The median (interquartile range) B. pseudomallei colony count in blood for 44 of 77 patients with positive blood cultures was 2.4 CFU/ml (0.2-13.5 CFU/ml); this may explain the low sensitivity of PCR for this specimen. The PCR assay described here is not sufficiently sensitive to replace culture in our clinical setting.
authors.affiliation: Mahidol-Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand. narisara@tropmedres.ac
authors.forename: Narisara
authors.initials: N
authors.lastname: Chantratita
authors.forename: Vanaporn
authors.initials: V
authors.lastname: Wuthiekanun
authors.forename: Direk
authors.initials: D
authors.lastname: Limmathurotsakul
authors.forename: Aunchalee
authors.initials: A
authors.lastname: Thanwisai
authors.forename: Wasun
authors.initials: W
authors.lastname: Chantratita
authors.forename: Nicholas P J
authors.initials: NP
authors.lastname: Day
authors.forename: Sharon J
authors.initials: SJ
authors.lastname: Peacock
mesh_terms: D016957:Burkholderia pseudomallei / Q000235:genetics* / Q000302:isolation & purification*; D006801:Humans; D008554:Melioidosis / Q000175:diagnosis* / Q000382:microbiology; D016133:Polymerase Chain Reaction; D012329:RNA, Bacterial / Q000032:analysis* / Q000235:genetics; D012336:RNA, Ribosomal, 16S / Q000235:genetics*; D012680:Sensitivity and Specificity
chemical_list: D012329:RNA, Bacterial; D012336:RNA, Ribosomal, 16S