DETECTION AND DIFFERENTIATION OF THE 6 BRUCELLA SPECIES BY POLYMERASECHAIN-REACTION

Background: Brucelosis is a severe acute febrile disease caused by bac teria of the genus Brucella. Its current diagnosis is based on clinica l observations that may be complemented by serology and microbiologica l culture tests: however, the former is limited in sensitivity and spe cificity, the latter is time consuming. To improve brucelosis diagnosi s we developed a test which is specific and sensitive and is capable o f differentiating the sis species of Brucella. Materials and Methods: Four primers were designed from B. abortus sequences at the well-conse rved Omp2 locus that are able to amplify the DNAs of all six species o f Brucella. Results: Our test detected all six species of Brucella. Th eir differentiation resulted directly from differences in the amplific ation patterns or was achieved indirectly using a RFLP present in one of the PCR products. The sensitivity and specificity of the new test w ere then determined; it was applied successfully in confirming the dia gnosis of a patient whose clinical history and serology indicated infe ction with Brucella. Conclusions: The results make possible the use of a PCR test for Brucella detection and differentiation without relying on the measurement of the antibodies or microorganism culture. Our fi rst results showed that the PCR test can confirm the presence of Bruce lla in blood samples of infected patients.