The general idea of sero-prognosis is personal with me.
In 18971 I showed in regard to typhoid fever that the intensity of the agglutinating power of the blood is in inverse proportion to the gravity of the infection and in direct proportion to the resistance of the patient. I established this by 112 observations on typhoid fever with studies of the agglutination curve and by numerous observations on animals. In like manner Griffon2 has shown that the maximum agglutinating power of the blood in pneumonia is found at the moment of recovery, and that this agglutinant power is wanting in mortal cases. In tuberculosis, which is not a cyclical disease, the facts are less conclusive. However, in conjunction with Arloing3 I have found, since 1898, that the agglutinant power of the blood is ordinarily greater in cases which are benign, or on the way to recovery, and
COURMONT P. SERO-PROGNOSIS OF TUBERCULOUS PLEURISIES.. JAMA. 1906;XLVI(20):1500-1502. doi:10.1001/jama.1906.62510470014001b