title: A prospective clinical study on the use of reverse transcription-polymerase chain reaction for the early diagnosis of Dengue fever.
abstract: Laboratory testing for dengue virus is used to confirm the diagnosis of dengue virus infection and to differentiate dengue from other febrile tropical illnesses. There are few data on the clinical use of reverse transcription-polymerase chain reaction (RT-PCR) for diagnosis of dengue virus infection. We prospectively evaluated 121 consecutive patients with possible dengue who had samples submitted for RT-PCR, IgM serology, and virus culture. Results were compared with the final discharge diagnosis. Semi-nested RT-PCR was performed using genus- and serotype-specific NS3 consensus primers. Results of 112 patients were available for the final analysis. The RT-PCR was positive in 40 of 62 patients with dengue. Patients who were RT-PCR-positive alone showed a mean of 4.4 days to RT-PCR positivity compared with 5.9 days in patients who were RT-PCR-negative and IgM serology-positive (P = 0.03, Mann-Whitney U-test). The sensitivity, specificity, negative predictive value, and positive predictive value were 70, 100, 84, and 100%, respectively, for samples analyzed within 5 days of illness onset. The RT-PCR also provided epidemiological data regarding the prevailing dengue virus serotypes: 25 with Den-2, eight with Den-3, and seven with Den-1 infection. We propose an algorithm of dengue testing that uses RT-PCR within 5 days of illness onset, whereas IgM capture enzyme-linked immunosorbent assay is preferred for those presenting later.
authors.affiliation: Rush University Medical Center, 600 S. Paulina Ave., ACC Suite 140, Chicago, IL 60612, USA. kamalsingh@lycos.com
authors.forename: Kamaljit
authors.initials: K
authors.lastname: Singh
authors.forename: Ajit
authors.initials: A
authors.lastname: Lale
authors.forename: Eng
authors.initials: E
authors.lastname: Eong Ooi
authors.forename: Lily-Lily
authors.initials: LL
authors.lastname: Chiu
authors.forename: Vincent T K
authors.initials: VT
authors.lastname: Chow
authors.forename: Paul
authors.initials: P
authors.lastname: Tambyah
authors.forename: Evelyn S C
authors.initials: ES
authors.lastname: Koay
mesh_terms: D003715:Dengue / Q000097:blood / Q000175:diagnosis*; D003716:Dengue Virus / Q000254:growth & development*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007075:Immunoglobulin M / Q000378:metabolism; D008297:Male; D011446:Prospective Studies; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D012680:Sensitivity and Specificity; D014158:Transcription, Genetic; D014776:Virus Cultivation
chemical_list: D007075:Immunoglobulin M