title: Atypical Dermatophilus congolensis infection in a three-year-old pony.
abstract: Dermatophilosis caused by Dermatophilus congolensis causes exudative dermatitis in a variety of species. The infection is generally limited to the cutaneous tissues, where infection is acquired from the environment and bacteria penetrate into keratinized epithelium through epithelial disruption. A 3-year-old pony filly was examined for enlarging mandibular lymph nodes during the preceding 10 months. Biopsy of the node revealed mixed and granulomatous inflammation and thick, filamentous Gram-positive bacteria. Dermatophilus congolensis, confirmed by biochemical testing and sequencing of the ribosomal RNA gene, was cultured from a sample aspirated from the infected site. Dermatophilus congolensis should be considered as a possible etiologic agent associated with lymphadenopathy and granulomatous inflammation in the horse.
authors.affiliation: Department of Pathology, Microbiology, and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA. bbyrne@ucdavis.edu
authors.forename: Barbara A
authors.initials: BA
authors.lastname: Byrne
authors.forename: Courtney L
authors.initials: CL
authors.lastname: Rand
authors.forename: Valerie R
authors.initials: VR
authors.lastname: McElliott
authors.forename: Eileen M
authors.initials: EM
authors.lastname: Samitz
authors.forename: Stephanie A
authors.initials: SA
authors.lastname: Brault
mesh_terms: D000192:Actinomycetales / Q000235:genetics / Q000302:isolation & purification*; D000193:Actinomycetales Infections / Q000382:microbiology / Q000662:veterinary*; D000818:Animals; D005260:Female; D006734:Horse Diseases / Q000382:microbiology*; D006736:Horses; D008198:Lymph Nodes / Q000382:microbiology; D012329:RNA, Bacterial / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics
chemical_list: D012329:RNA, Bacterial; D012335:RNA, Ribosomal