ACTINOMYCOSIS can be successfully treated with penicillin or, when possible, with a combination of penicillin and excisional surgery. Specific diagnosis is often simple and depends mainly upon an awareness of this entity and its differentiation from a similar disease, nocardiosis, which is unaffected by penicillin but responds readily to the sulfonamides.
The actinomycetes are anaerobic to microaerophilic gram-positive organisms with branching, filamentous mycelia and are more closely related to the true bacteria than to the true fungi. They have the distinction of being the only fungi which are capable of causing systemic infection and which cannot grow aerobically on ordinary culture mediums at room temperature. Various species and types have been described. Actinomyces bovis generally causes bovine disease, A. Israeli, human disease, and A. baudetti, disease in dogs and cats. There are minor differences in the appearance of the colonies of the species, and definite separation can be made by