Specific Soluble Substances of the Pneumococcus in the Blood in Pneumonia.

Abstract

Avery and Dochez 1 detected the specific soluble substances of the pneumococcus in the urine of patients with pneumonia, and on the basis of their observations the determination of the type of pneumococcus causing the lesion in the lung may often be accomplished early in the course of the disease.

There is every reason to believe that the specific substances are brought to the kidney by the blood and concentrated in the urine. It is believed by some that the precipitin occurs in the urine only in cases with organisms in the blood. Our own observations have shown that at least the soluble antigen may be detected even where the blood culture is negative. It is of course possible that, as many believe, the pneumococci were present in the blood very early in the course of the disease and could not be found by blood culture when the patient came into the hospital. Since the specific soluble substances are so readily diffusible, it is not necessary to presuppose that organisms must be present in the blood when the soluble substances are detectable in the urine.

Since the soluble substances give a precipitate under appropriate conditions in high dilution, it might be possible to detect them early in the course of the disease and thus determine the type for serum treatment when specimens of sputum and urine are not obtained. But Blake, 2 using the untreated serum from patients with pneumonia, obtained precipitation by adding type specific antipneumococcus serum, only relatively late in the disease, on the sixth day. Out of 17 cases, he found the soluble substances in only 2 (one was a type II and the other Friedlander's bacillus infection).

By concentrating the ultra filtrate or the filtrate from coagulated patient's serum, the specific soluble substances in all 3 types have been found, and in one as early as the thirteenth hour after the initial chill.