[Lymphoblast transformation test in osteoarticular tuberculosis].

Bacteriological proof of an osteoarticular tuberculous lesion is difficult to obtain, notably in Pott's disease. The authors, on the basis of earlier work in the field of pulmonary pathology, wished to assess the value of the lymphocyte transformation test in the diagnosis of this disease. Old tuberculin from the Pasteur Institute and LP48 tuberoulin were used at different concentrations. Out of 10 tuberculous patients (8 with Pott's disease and 2 with white tumours), 9 had positive tests, of which 7 were strongly positive ; the average transformation value was 13 percent. This positiveness was a function of the condition of the patient, of the extent of the lesions, and of the treatment. Of the 25 control patients affected by an infectious, nonmicrobial or other osteoarticular process, 17 gave negative results in the test, and 8 were positive, two of whom had high values. The average transformation value was 4 percent. From this study it seems that a negative result in the LTT is a valuable argument against the diagnosis of osteoarticular tuberculois ; a weak positive result indicates tuberculin hypersensitivity without absolutely defining evolution of tuberculois ; a strongly positive test may be encountered in hyperergic states connected with prolonged infectious conditions in bones or joints.