Cutaneous reaction to pneumococcic filtrates.

Abstract

Pneumococcus filtrates supplied by Olsen have been injected into mice intraperitoneally. A limited number of mice which received one injection of the filtrate in this way, when killed 24 to 48 hours later, showed marked congestion of the lungs. Microscopic sections showed congestion with hemorrhage throughout the lungs.

The filtrate was injected intracutaneously in 17 normal individuals, as well as three convalescent pneumonia cases who had received pneumonia antitoxin. Nine of the 17 healthy individuals gave a positive skin test and 8 a negative reaction. The convalescent pneumonia patients were all negative. The positive skin tests were present in about 8 hours following the injection, reached the height of their reactions in about 24 hours, after which they began to fade. At the end of 48 hours the reactions had all disappeared.

These observations, considered with those presented by Olson, indicate that his filtrates contain a soluble toxin.