Amplification of ST50 gene using dry-reagent-based polymerase chain reaction for the detection of Salmonella typhi.
Conventional polymerase chain reaction (PCR) testing requires many pipetting steps and has to be transported and stored in cold chain. To overcome these limitations, we designed a ready-to-use PCR test for Salmonella typhi using PCR reagents, primers against the ST50 gene of S. typhi, a built-in internal amplification control (IAC), and gel loading dye mixed and freeze-dried in a single tube. The 2-step dry-reagent-based assay was used to amplify a 1238-bp target gene and an 810-bp IAC gene from 73 BACTEC blood culture broths (33 true positives for S. typhi and 40 true negatives for non-S. typhi). The sensitivity, specificity, positive predictive value, and negative predictive value of the PCR assay were 87.9%, 100%, 100%, and 90.9%, respectively. We suggest that this rapid 2-step PCR test could be used for the rapid diagnosis of typhoid fever.
Aziah
Ismail
I
Institute for Research in Molecular Medicine, Health Campus, Universiti Sains Malaysia, 16150 Kubang Kerian, Kelantan, Malaysia.
Ravichandran
Manickam
M
Ismail
Asma
A
D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001769:Blood / Q000382:microbiology; D003470:Culture Media; D004587:Electrophoresis, Agar Gel; D005612:Freeze Drying / Q000379:methods*; D006801:Humans; D007202:Indicators and Reagents; D016133:Polymerase Chain Reaction / Q000379:methods*; D012485:Salmonella typhi / Q000235:genetics / Q000302:isolation & purification*; D013997:Time Factors; D014435:Typhoid Fever / Q000175:diagnosis* / Q000382:microbiology
D001425:Bacterial Outer Membrane Proteins; D003470:Culture Media; D007202:Indicators and Reagents