A Case of Trichomycosis Axillaris : Bacteriological and Electromicroscopic Observations

Abstract

Pale yellowish casts on axjllary hairs of a 17 year-old high school student were studied bacteriologically and electronmicroscopically. The casts attached to the hair shaft very hardly and could not be separated from it. It did not stain with 1 dimethylaminocinnamalaldehyde which stains keratin cast of internal root sheeth origin in red color. Culture on blood agar grew creamy pale yellow colonies. Gram-positive bacillus was isolated from this culture and corynebacterium was identified by specific examinations. A scanning, electronmicroscopic examination revealed rough surfaced large masses protruding from hair shaft on the surface of which innumerable number of bacillus were oberved inbetween discrete keratinous materials. In early lesions a group of bacilli was observed growing on the surface of hair cortex destructing hair cuticle. In transmission electronmicroscopic examination, a wide area composed of bacterial masses was present on the outer part of the lesion in lossed cuticular area. Beneath it was observed dyskeratotic cortex within which were also detected small amount of bacteria. It was concluded that corynebacteria grew under the cuticle on and in the cortex of hair shaft developing large masses. © 1985, Meeting of Osaka Dermatological Association. All rights reserved.