Histopathological Changes with Time in Experimental Microsporum gypseum Infection of Rabbits

Hwang, Kae Yong; Choi, Jong Soo; Kim, Ki Hong; Lee, Tae Sook

Abstract

To evaluate the progress of clinical and histopathological changes of dermat ophytosis caused by M. gypseum, its inoculation study was done in 16 male New Zealand white rabbits(control: 4, innoculation : l2). The results were as follows . Clinically Initial erythema, scales, and crusts developed in 1 week after inoculation. They reached maximum severity on the 14th to 18th day and disappeared on the 25th to 44th day after inoculation. I-Iist,opathologically : The earliest findings were mild focal acanthosis and for al vascular ilatations and cellular infiltrations of the papillary dermis on the 4th day after inoculation. Their severity increased to the moderate degree until the. 8th day when mild hyperkeratosis was notec1, and lasted to the 13th day, Maximum degree of the findings including parakiratosis, intraepidermal microabscesses and middermal changes was seen on the 16th to 22nd day, and disapveared gradually between the 25th day and the 46th day. Hyphae and spores were founil on the PAS stainings until the 22nd clay. M. gypseum was not cultured from the lesions after the 25th day. seven of 10 rabbits injected intradermally with trichophytons became positive in 2 to 4 weeks after inoculation. All these findings suggest that the maximum inflammatory response is the result of immunologic reaction and the increased epidermal turnover rate may play a. major role in the shedding of remained fungi of the horny layer.