Objective To evaluate the application effect of a rapid PCR method for detecting Corynebacterium striatum (C. striatum) in clinical isolates and clinical sputum specimens.
Methods A single PCR method for the detection of C. striatum was established using PCR primers Cst_1-F/Cst_1-R designed for the species-specific gene ftr1. The C. striatum reference strain ATCC6940, ATCC43751, 152 clinical isolates and 30 non-C. striatum strains was used to verify the effectiveness of this method. The resultof this PCR method was compared with that of 16S rRNA gene sequencing and MALDI-TOF MS.The specificity and sensitivity of this PCR method were evaluated. Finally, this PCR method was used to detect 88 clinical sputum specimens.
Results The result of the PCR method was 100% consistent with that of 16S rRNA sequencing and MALDI-TOF MS in the identification of 152 C. striatum clinical isolates. There was no cross reaction in 30 non-C. striatum strains.The limit of detection was 1 ng template DNA per reaction.When applied this PCR method to detect clinical sputum specimens, the consistency of this method compared with sputum smear microscopy was 86.4% (76/88).
Conclusion As a convenient, economic and effective method, the PCR assay in this study may replace 16S rRNA gene sequencing and MALDI-TOF MS for the clinical identification of C. striatum. Also, this assay has good application effect in the detection of C. striatum in clinical sputum specimens.