A reverse passive latex agglutination test for the diagnosis of systemic candidosis

A new reverse passive latex agglutination test for the detection of serum antigen in systemic Candida albicans infection is reported. 1700 sera were examined from 91 patients who had either proven or suspected systemic candidosis, 183 patients who were colonized and 636 patients with no evidence of candidal infection. Thirty of the systemically infected patients had lymphoproliferative disorders and the rest a variety of surgical or medical diseases with no underlying neutropenia. The latex particles were sensitised with an antiserum raised in rabbits against a pressate of Candida albicans. The degree of antigenaemia was proportional to the likelihood of invasive disease such that a diagnostic cut-off point of 1 in 8 produced a test for systemic candidosis with a sensitivity of 90% and specificity of 80.4% in patients with lymphoproliferative disorders. In the remaining medical and surgical patients a diagnostic cut-off point of 1 in 10 produced a test with a sensitivity of 96.7% and specificity of 98.8%. The patients with lymphoproliferative disorders tended to produce lower serum antigen levels. The sera were also assayed for antibody using latex particles sensitised with pressate.