Experimental detection of DNA of Brucella in peripheral blood lymphocytes

ObjectiveTo investigate the feasibility of the diagnosis potential of Brucella nucleic acid detection in peripheral blood lymphocytes for patients with a tube agglutination titer (SAT) less than 1∶100 and disease duration less than one year.

MethodsThe blood samples of the patients were collected for peripheral blood lymphocytes and serum isolations. Then, the nucleic acid extraction was conducted, and PCR amplification was performed by using the Brucella identification primer B4/B5 to detect the presence of Brucella DNA in the collected samples.

ResultsA total of 278 blood samples from patients with brucellosis were collected from January 2017 to February 2018, of which 82 had a SAT of 1∶100 or less, and the disease duration did not last for one year. In 82 patient samples, 50 out of 82 peripheral blood lymphocyte samples were positive for nucleic acid of Brucella, while 15 of 82 serum samples were positive for nucleic acid of Brucella, the difference was significant (P＜0.05). Among the SAT (-), 1∶25, 1∶50, 1∶100, 1∶200 of serum antibody titers, the SAT(-) group had the highest detection rate of Brucella DNA in whole blood lymphocytes, while the 1∶200 group had the lowest detection rate.

ConclusionThe detection of Brucella nucleic acid in peripheral blood lymphocyte can be used for the diagnosis of brucellosis in cases with negative serum antibody detection, providing a new method for the diagnosis of brucellosis.