THE USE OF SERIAL HEMAGGLUTINATION TESTS IN FOLLOWING THE COURSE OF TUBERCULOSIS IN CHILDREN
1. In cases of known pulmonary (or meningeal) tuberculosis in which X-ray (or spinal fluid) findings have become stabilized, a rise or fall in a previously stable hemagglutinin titer is a reliable indication that X-ray (or spinal fluid) evidence of improvement of the disease will follow within a few weeks. 2. A change in hemagglutinin titer occurring simultaneously with improvement in X-ray (or spinal fluid) findings serves as reliable additional evidence of improvement of the disease. 3. The significance of a changing hemaglutinin titer must always be evaluated with reference to X-ray (or spinal fluid) findings. A changing titer can be considered evidence of impending or beginning improvement of the disease only if the X-ray (or spinal fluid) findings are either static or improving. 4. A changing hemagglutinin titer was useful in predicting or confirming improvement of tuberculous disease in 38% of the group of cases studied. In the remaining cases, a change in hemagglutinin titer either failed to occur at all, or did not occur until after definite X-ray (or spinal fluid) improvement had taken place. 5. The absolute height of the hemagglutinin titer, in itself, was of no prognostic significance in connection with the course of tuberculosis in children. 6. In following the course of tuberculosis, the hemagglutination test is of more value in older children and in children with relatively mild forms of the disease than in infants or in patients with severe forms of tuberculosis, because the former are more likely to develop positive tests. 7. Tuberculin testing did not interfere with the use of the hemagglutination test in following the course of tuberculous disease.