Acute Respiratory Diseases among Troops with Especial Reference to Empyema.

Respiratory infections in 1917 and 1918 occurred among troops in waves, the greatest severity of the diseases being at the height of each wave.Not only were empyema and pneumonia more frequent and severe, but also tonsilitis, pharyngitis and bronchitis.The most serious infections were characterized by septicemia with empyema, peritonitis, phlegmon and rarely arthritis, and also by pulmonary infection (pneumonia lobular or lobar in distribution) with consecutive empyema.While patients who were passing through measles infections were more severely affected by the streptococcal invasion, the two infections should be regarded as separate, even though they were coincident.The empyema and pneumonia were not the result of the measles infection but of the prevailing severe respiratory in fections of that period.The marked freedom from complications of the group of measles treated during the fall and winter of 1917, when general streptococcal infections were absent in camp, and the severe wave of pneumonia and streptococcal empyema of April 1918, when measles was on the wane, and which involved for the most part soldiers who had not had measles, are points in support of this view.In a group of 115 consecutive cases of pneumonia and empyema, a definite history of an acute antecedent bronchitis, pharyngitis or tonsilitis was obtained in over 80 0/0 of the cases.In the majority of cases of empyema, a streptococcus has been the causative organism.When grown on blood agar it has been shown to be usually hemolytic.During the period of prevalence of empyema, streptococci were demonstrable in the majority of the throats of healthy soldiers as well as of patfents entering the jhospital with respiratory infections.The clinical manifestations of empyemaincluderapid and profound toxemia, the quick formation in many cases of large amounts of pleural exudate, and a marked tendency to pocket formation by old and new adhesions in atypical locations.