The Efficacy of Multiplex PCR in Comparison with Agglutination and ELISA in Diagnosis of Human Brucellosis

Objective: Brucellosis is a zoonotic disease of which diagnosis is based on clinical symptoms and positive laboratory findings. Since serology tests are not specific and sensitive enough, polymerase chain reaction (PCR) can be an alternative method in making the final decision in suspicious cases. In this study, three diagnostic methods were compared in suspected patients with brucellosis in the endemic area of Mianeh, Iran.

Patients and Methods: In this descriptive study, results of standard agglutination test (SAT) and specific immunoglobulin (Ig) G and IgM by enzyme-linked immunosorbent assay (ELISA) were compared with Multiplex PCR in 100 patients with suspected brucellosis referred to the Imam Khomeini Hospital, Mianeh, Iran. Their sera were collected and tested by SAT, ELISA and Multiplex PCR. DNA was extracted from serum samples and examined by Multiplex PCR involving specific primers for B. melitensis and B. abortus based on IS 711 in the brucella chromosome.

Results: We found 28 cases with positive results for B. melitensis by Multiplex PCR technique which was significantly different from of SAT (P<0.05). Six samples were positive for B. abortus by PCR.

Conclusion: The results of present study showed that Multiplex PCR assay is a rapid and sensitive technique for diagnosis of brucellosis compared to SAT. However it is more accurate when coupled with conventional methods.