SPECIFIC SERUM AGGLUTINATION OF KAOLIN PARTICLES SENSITIZED WITH TUBERCLE PHOSPHATIDE AND ITS CLINICAL EVALUATION AS A SERODIAGNOSTIC TEST FOR TUBERCULOSIS

Abstract

Convincing evidence is given that the phosphatide kaolin-agglutination test is a reliable quantitative method in the diagnosis of pulmonary tuberculosis in humans. The test was positive in 95.4% of 1402 patients with pulmonary tuberculosis, giving an average antibody titer of 55.8; while only 12.9% of 303 tuberculin-positive healthy persons reacted positively in the low range of antibody titers, showing an average titer of 1.5. The amounts of antibody to phosphatide were shown to be significantly proportional to the clinical symptoms, the bacteriologic findings, and the activity of the disease. Tuberculin-positive, nontuberculous patients with various diseases gave positive reactions more frequently than tuberculin-positive healthy subjects, but both groups for the most part had low-range titers of 8 and 16. Higher false positive reactions were encountered, although rarely, in patients suffering from chronic, organic, or allergic diseases. In view of the gradual histopathologic changes which take place from the initial stage of infection to clinical onset of the disease, it is proposed that the low titers of 8 and 16 be considered intermediate reactions and the titers from 32 upward as strong reactions.