The Significance of Prolonged Streptococcal Antibody Development In

It has been shown that patients with rheumatic fever continue to produce antibodies to hemolytic streptococcus for months after the subsidence of an apparently transient respiratory infection. The various clinical types of rheumatic fever are accompanied by characteristic types of antibody response. In monocyclic attacks with acute onset, a period of severe illness, and relatively rapid recovery, the titer reaches maximum relatively early-within a month of the onset of rheumatic symptoms. In attacks with insidious onset, where repeated cycles of progressive severity culminate in severe carditis months later, the titer rises more gradually, reaching its maximum height late in the illness (1). This close relation between the course of antibody production and the clinical character of the rheumatic attack has stimulated us to investigate the underlying reason for the prolonged development of streptococcal antibody in this disease. The simple hypothesis that the infectious agent persists throughout the period of rising titer, does not lend itself to direct proof or disproof in the human subject. During convalescence from pharyngitis, hemolytic streptococcus commonly disappears from the mucosa of the upper respiratory tract, and only the occasional patient furnishes the opportunity to recover it later from deeper tissues, such as an accessory sinus, middle ear, or tonsils. The impossibility of thorough bacteriological studies of deep tissues in human subjects has obliged us to use an indirect approach to explain the significance of prolonged antibody development. The purpose of this paper is to summarize such indirect evidence as we have been able to obtain, and to indicate its bearing on the rheumatic fever problem. The data have been collected from naturally occurring throat infections in human subjects and from experimental infections in the guinea pig. 1 The work reported in this communication was carried out under the W. K. Kellogg Foundation Fund. I. THE PROLONGED DEVELOPMENT OF BOTH ANTI-