On the Relation of the Serum Ereptase (Peptidase) Titer to the Clinical Course in Pneumonia

Abstract

During the course of recent years a number of investigators have emphasized the possibility that a definite relation exists between the inception of the crisis in pneumonia and the activation of the proteolytic ferments in the area involved. Edsall and Pemberton1 in particular have advanced this idea and endeavored to make the logical clinical application of hastening autolysis as a therapeutic measure in cases of delayed resolution. Later, Jobling2 studied the serum ferments and antiferment during the course of pneumonia, noting the fact that just preceding the crisis protease was demonstrable in the serum, while the antiferment began to diminish from the high titer prevalent throughout the early part of the disease. The fundamental idea underlying the several studies in this direction has been that, apart from the intoxication arising directly from and incident to the growth of the pneumococcus, toxic split products were probably absorbed from the exudate, which could be considered a mass of foreign protein undergoing slow digestion before the crisis. Active autolysis once underway, only the lower and nontoxic products of digestion would be absorbed, and the environment for the continued proliferation of the pneumococcus would become unfavorable, as Almagia3 has suggested. In this phenomenon the primary reaction is of course local and cellular, involving the liberation of sufficient leukoprotease from leukocytes to overcome the inhibiting factors. These latter are very probably the antiferment of the serum and the exudate. Of the varieties of proteolytic ferments involved in such a digestive process, the titer of the peptidase or ereptase during the course of pneumonia has not been studied. This form of enzyme activity would