[The value of the immunoglobulin G avidity test for the serologic diagnosis of XXXX ].

@entity1 @entity281 @entity3377 @entity1133
In order to investigate the value of immunoglobulin G (IgG) avidity test for the serological diagnosis of @entity281 , a total of 118 @entity1 (74 male, 44 female; mean age: 43 +/- 18.7 years) were included into the present study. The @entity1 have been diagnosed with the characteristic clinical findings, > or = 1/160 antibody titers in standard tube agglutination (STA) test and/or blood culture positivities. Brucella spp. have been grown in blood cultures of 78 @entity1 , and STA test results were found positive (> or = 1/160 titers) in 117 @entity1 . The diagnosis of a @entity1 with 1/80 STA titer was based on the blood culture positivity. By enzyme immunoassay (ELISA), 3 @entity1 (2.5%) were found positive for IgM, 14 (11.9%) were positive for IgG, and 101 (85.6%) were positive for both IgM and IgG. The @entity1 who were found IgG positive have been grouped according to their duration of complaints. Group 1 included 99 @entity1 with the history of @entity3377 < or = 6 months, and group 2 included 16 @entity1 with the history of @entity3377 > 6 months. IgG avidity test was performed by ELISA in 115 IgG positive serum samples, with the denaturation substance (8 M @entity1133 ). The cut-off value for IgG avidity index (AI) was accepted as 40%, and the avidity maturation period was defined as 6 months. As a result, the rates of @entity1 who had low IgG AI in group 1 and 2 were found as 91.9% and 43.7%, respectively, while these rates were 8.1% and 56.3% for the presence of high IgG AI, respectively. The rate of low AI in group 1 was an expected result, while the rate was more than expected in group 2, indicating that Brucella antibodies with low avidity indices would not be helpful for the diagnosis of a recent infection, while Brucella antibodies with high avidity indices would be useful for the elimination of a recent infection.
