Polymerase chain reaction (PCR) technique compared to conventional bacteriological and serological techniques in diagnosis of human brucellosis in Egypt

Direct diagnosis of human brucellosis is performed by cultivation with the disadvantage of being time consuming and the increase risk of laboratory acquired infection to laboratory personnel handling and performing culture procedures. Serological techniques as serum agglutination test (SAT) can also be used for diagnosis with the disadvantage of false negative and positive results that may occur. This study aims to evaluate polymerase chain reaction (PCR) technique sensitivity and specificity for diagnosis of brucellosis in comparison with the conventional bacteriological and serological techniques. Blood samples were withdrawn from 40 patients suspected to have brucellosis. Blood culture, SAT, and PCR technique were performed. It was found that PCR had high sensitivity (100%) when culture is the gold standard more than if SAT is considered the gold standard (88%). Specificity of PCR is more (40%) when SAT is considered the gold standard than if culture is the gold standard (37.5%). Molecular diagnosis of human brucellosis by PCR is faster and more sensitive than culture and serology.