Scarlatinal Nephritis Experimentally Induced in the Dog. ∗

Abstract

Since the publication 1 of the results of our studies upon experimental nephritis in the rabbit with the toxic principle of Streptococcus scarlatinae, we have found that the dog is a more satisfactory animal for the purpose of causing nephritis with this particular injurious agent. This animal has proven to be not only highly susceptible to infection but developed regularly a severe and often fatal form of acute glomerulonephritis following the injection of the specific streptococcal toxin alone. None of the animals showed at any time an exanthem; however, it is significant that the induced kidney lesions completely correspond histopathologically to the glomerular and acute interstitial scarlatinal nophritis of man.

This communication is a brief report of the effects upon the kidneys of the dog produced by the viable culture and also the pure toxin of Streptococcus scarlatinae.

All dogs employed in the experiment were healthy and under three years of age. The animals were kept under close observation for a period of ten days prior to inoculation, during which time daily analysis of the urine was made and the blood chemistry determined. Only dogs that showed normal kidney function throughout this period were selected for the experiment. The preliminary study of the urine and blood was carried out by our colleague. Professor Denis, of the department of biochemistry.

Infectivity of the Dog. Six full-grown, healthy clogs were inoculated with living cultures of Scarlatinal streptococcus. Two animals received the injection intravenously, two subscutaneously and two intraperitoineally. In each instance the dosage was 10 mills of the surface growth from slanted sheep-serum agar which had been washed off and sususpended in 50 mils of sterile normal saline.