[Gene detection of Neisseria spp. isolated from male patients with genitourinary tract infections].

OBJECTIVE

To detect the genes of Neisseria spp. isolated from patients with male genitourinary tract infections, and to study the pathogenicity of non-gonococcal strains of Neisseria and the laboratory diagnosis for the infections caused by Neisseria spp.

METHODS

Using polymerase chain reaction and nucleotide sequencing, we amplified and sequenced 4 genes of Neisseria spp. isolated from patients with male genitourinary tract infections, including 16S rRNA, orfl, cppB and nspA.

RESULTS

Fourteen Neisseria strains were identified through analysis of the 16S rRNA gene, including 3 N. mucosa strains, 3 N. cinerea strains, 2 N. gonorrhoea strains, 2 N. sicca strains, 2 N. subflava strains, 1 N. lactamica strain, and 1 N. polysaccharea strain. Among them, 9 showed positive results in gonococcal fluorescence-labeled multiplex-PCR detection, 1 in cppB gene reaction, 5 in orfl gene reaction, and 3 in nspA gene reaction. The consistency rate was 85.7% between the above results from our gene detection and those from the routine bacteriological methods.

CONCLUSION

The cppB gene is absent in the non-gonococcal strains of Neisseria spp. that can cause male genitourinary tract infection. Most of the strains not only lack virulence-associated orfl and nspA genes, but also show positive results in gonococcal fluorescence-labeled multiplex-PCR detection, which is one of the important reasons for the misdiagnosis and missed diagnosis of gonorrhea infection. The combination of routine bacteriological methods and gene detection in laboratory examinations may help improve the accuracy rates of Neisseria species identification and clinical diagnosis of the infections caused by Neisseria spp.