THE SIGNIFICANCE OF MIXED INFECTIONS IN PNEUMOCOCCIC PNEUMONIA

Abstract

It is my purpose in this communication to call attention to an important group of cases of pneumococcic pneumonia in which multiple bacterial agents are operative. The significance of these mixed infections in altering the course and outcome of the disease and in evaluating the effects of certain specific therapeutic agents will be brought out by citing a few examples. Numerous instances of cases from which more than one strain or species of bacterium were isolated in the course of the disease may be found in the literature concerning pneumococcic pneumonia. Either most of these instances are recorded as part of intensive bacteriologic investigations of small groups of cases or they are mentioned in the reports of clinical and bacteriologic studies of large numbers of pneumonia cases.¹In such reports little attention has been given to the significance of each of the various agents and its rôle in the