The Value of Bacteriological Studies in Pneumonia Occurring in Age Group 15-60

1. In the age group 15-60, 625 cases with pneumonia admitted to The Rochester General Hospital from 1948 through 1953 were reviewed. 2. Particular attention was paid to coexistent diseases and bacteriological studies in relation to the course of the disease and the treatment received. 3. With routine antibiotic therapy the course of the disease was dependent more upon the presence of coexistent disease than upon the virulence of the causative organism. 4. In 340 cases of pneumonia without significant coexistent diseases, bacteriological studies were of possible value as a guide to therapy in only five and even these were doubtful. 5. In cases of pneumonia in the age group 15-60 without significant coexistent disease, it is felt that routine bacteriological studies are unnecessary. 6. A classification of pneumonias based on the presence of coexistent disease is presented as a guide to treatment and prognosis. It is felt that this will be generally more useful to the clinician than previous classifications based on bacterial etiology.