[Evaluation of diagnostic value of Brucellacapt test in brucellosis]

Although standard tube agglutination (STA) test is the most preferred method for the serodiagnosis of brucellosis, it may yield false negative results because of its incompetence in detecting the blocking (non-agglutinating) antibodies. Blocking antibodies can be detected by Coombs' test (anti-human globulin test), which is generally not performed in laboratories routinely since it is a time consuming and laborious method. Recently more practical Brucellacapt (immunocapture-agglutination) test is being used for the detection of total antibodies without any interference of the presence of blocking ones. The aim of this study was the evaluation of the value of Brucellacapt test in the serodiagnosis of brucellosis. Twenty-five brusellosis patients whose blood cultures yielded Brucella melitensis growth, and 31 healthy subjects as controls, were included to the study. Serum samples obtained from all of the 56 subjects have been searched by STA, Coombs' and Brucellacapt methods, and threshold titre was accepted as 1/160. As a result, 40% (10/25) of culture positive patients were found positive (> or =1/160) by STA, whereas 92% (23/25) were positive (> or =1/160) by both Coombs' and Brucellacapt tests. No positivity was detected in the control group by any one of those three tests. The agreement between Coombs and Brucellacapt methods was found as 100%, while the sensitivity and specificity of Brucellacapt test were estimated as 92% (23/25) and 100% (31/31), respectively, when the culture was accepted as reference method. Although our data have pointed out the high performance of Brucellacapt test in brusellosis serodiagnosis, confirmation with further data carried on extensive and comprehensive study groups, are needed.