Evaluation of molecular and serological methods for the diagnosis of brucellosis in human

Objective: Diagnosis of brucellosis from human suspect to have brucellosis by serological methods include: Rose Bengal test and ELISA and comparison with PCR technique s in diagnosis of human brucellosis. Duration and place of study: Samples were obtained from suspected brucellosis patients, referred to many hospitals in Baghdad city, which include: Al-Yarmook, Al-Karama, Al-Shaheed Al-Sadder, Al-Imam Ali (peace be upon him) and Al-Kadhmiya Hospitals, during the duration from (November 2009 to November 2010). Methodology: A total 178 peripheral blood samples were from patients suspect to have brucellosis. The diagnosis of brucellosis was established by clinical findings confirmed by Rose Bengal test, ELISA, and molecular methods by PCR technique. DNA extraction was carried out using a commercial kit and a laboratory extraction procedure and examined by PCR involving specific primers for B.melitensis and B.abortus based on IS711 in the Brucella chromosome. Results: We identified 108 samples were positive result by RBT and 10 samples were positive result by ELISA for the detection of IgM (as a result of acute stage) and 22 samples were positive result for the detection of IgG (as a result of chronic stage). When PCR technique was applied to patients blood, 13 patient blood samples were positive, which include: 3 patient blood samples were positive for B.melitensis and 10 patient blood samples were positive for B.abortus. Conclusions: The results of present study showed that PCR assay is a rapid and sensitive technique for diagnosis of brucellosis compared to serological methods. However it is more valuable when coupled with serological methods.