A woman who pricked her finger while pruning some rose bushes develops a local pustule that progressed to an ulcer. Several nodules then developed along the local lymphatic drainage. The most likely etiological agent would be

Sporotrichosis is a chronic infection involving cutaneous, subcutaneous and lymphatic tissue. It is caused by Sporothrix schenckii. Pathogenesis: 1. Lesions on the exposed pas of the skin follow minor trauma. Nodules are first formed, followed by ulceration and necrosis of nodules. 2. From the lesions in skin and subcutaneous tissue, the infection can spread by lymphatic channels to lymph node and lymphatics are hardened and cord-like. Ref: Textbook of Microbiology, Ananthanarayan and Paniker; 9th edition