Sporotrichosis is an infectious granulomatous disease of fungous origin. The causative organism is Sporotrichum schenckii, which is found in nature on plants, flowers, and trees, as well as in animals, insects, and birds. Sporotrichosis is most commonly seen in farmers, florists, and laborers. It is to an extent an occupational disease.
The localized lymphatic type of sporotrichosis is the commonest. constituting 70 per cent or more of reported cases. The disease occurs in skin and subcutaneous tissue and appears in an upper extremity in the majority of cases. The primary lesion is generally an ulcer at the site of inoculation of Sporotrichum schenckii. The ulcer most frequently appears on the hand, with secondary nodular and ulcerative lesions appearing subsequently in ascending fashion along the lymphatic channels. Secondary lesions may number three to forty or more.