title: Skin pustules and nodules caused by Actinomyces viscosus in a horse.
abstract: A 12-year-old Arabian stallion was evaluated for a refractory skin problem of 2 years' duration. Skin nodules and pustules, which would rupture, had developed over the right lumbar muscles. Anaerobic culturing from the pustules yielded Actinomyces viscosus, and histologic examination of biopsy specimens revealed globular eosinophilic structures. Concomitant treatment with isoniazid (8 mg/kg of body weight, q 24 h for 8 weeks), trimethoprim-sulfadiazine (30 mg/kg, q 24 h for 8 weeks), and sodium iodide solution (66 mg/kg, every 1, 2, or 4 weeks, for 32 weeks) resolved the condition.
authors.affiliation: Department of Food Animal and Equine Medicine and Surgery, College of Veterinary Medicine, North Carolina State University, Raleigh 27606.
authors.forename: T E
authors.initials: TE
authors.lastname: Specht
authors.forename: B A
authors.initials: BA
authors.lastname: Breuhaus
authors.forename: T O
authors.initials: TO
authors.lastname: Manning
authors.forename: R T
authors.initials: RT
authors.lastname: Miller
authors.forename: R B
authors.initials: RB
authors.lastname: Cochrane
mesh_terms: D000196:Actinomycosis / Q000662:veterinary*; D000818:Animals; D006734:Horse Diseases / Q000382:microbiology*; D006736:Horses; D008297:Male; D012874:Skin Diseases, Infectious / Q000382:microbiology / Q000662:veterinary*; D012872:Skin Diseases, Vesiculobullous / Q000382:microbiology / Q000662:veterinary*