Experimental Sporotrichosis in Mice *

Abstract

Summary 1. Chronic progressive sporotrichosis of an extremity, rather like human sporotrichosis, was produced in the white mouse by a single injection, into the paw, of a suspension of Sporotrichum Schenckii, or of pus from human sporotrichosis. Such injections were made in 47 mice. Massive sporotrichosis of the foot and later of the ankle developed. The process lasted about two months and some mice recovered spontaneously. Several mice died from generalization of the disease after two and three months. 2. Intraperitoneal injections of the same inoculums resulted in peritoneal sporotrichosis which spread to the liver and sometimes elsewhere, as to the lungs, pleura, tail, and extremities. Intraperitoneal injections were made in 52 mice. Death was produced by the sporotrichosis in many mice at about 3 weeks or at about 12 weeks. 3. The experimental disease, whether of extremity or peritoneum, was characterized by the growth of enormous numbers of the tissue form of the organism, especially within macrophages. It was thus a cytomycosis, like human histoplasmosis. The abundance of organisms in the lesions of the mouse is in contrast to the paucity of organisms in human lesions. The lesions were suppurative, necrotizing and fibrosing, as well as macrophagic. 4. Six strains of Sporotrichum Schenckii from human cases of sporotrichosis in various parts of the world produced identical lesions in the mouse, while a seventh strain was only feebly pathogenic.