By Joseph Taboada , DVM, DACVIM, Office of Student and Academic Affairs, School of Veterinary Medicine, Louisiana State University Last full review/revision Mar 2018 | Content last modified Mar 2018 Epizootic lymphangitis is a chronic granulomatous disease of the skin, lymph vessels, and lymph nodes of the limbs and neck of Equidae caused by the dimorphic fungus Histoplasma farciminosum. The disease is seen in Asian and Mediterranean areas but is unknown in the USA. The fungus forms mycelia in nature and yeast forms in tissues and has a saprophytic phase in soil. Infection probably is acquired by wound infection or transmission by bloodsucking insects.