[A new bioassay model of antibiotic susceptibility by corneofungimetry].
OBJECTIVE
To study the value of a new bioassay model of antibiotic susceptibility by corneofungimetry which is more similar to human internal environment.


METHODS
Twenty-one healthy adult volunteers, 12 males and 9 females, aged 32 (22 - 41), were randomly divided into two groups to receive itraconazole 200 mg Bid or 200 mg qd or bid for one week. Stratum corneum strippings were taken from the forearm skin once before administration of itraconazole and 1, 4, 7, 10, 14, 21, 28, and 35 days after administration of itraconazole. Spores of selected fungi (Trichophyton rubrum, T. mentagrophytes, Microsporum canis, Candida albicans, C. glabrata and C. tropicalis) were deposited and cultured on the strippings. PAS stain was used after one-week culture to observe the growth of the fungi by computerized-assisted image analysis to measure the area covered by the yeasts and the dermatophyte.


RESULTS
All fungi grew on all the stratum corneum strippings with different numbers of hyphae. The areas covered by hyphae and spores decreased gradually after administration of itraconazole, became the smaller on the seventh day (P = 0.01 or P < 0.01), and began to increased since the 10 th day, and became almost the same sizes as those before the administration of itraconazole on the 35 th day.


CONCLUSIONS
Similar to the human internal environment, corneofungimetry is a useful new model of bioassay for antibiotic susceptibility.
Zhao
Jun-ying
JY
Department of Dermatology, Beijing Friendship Hospital Affiliated to Capital University of Medical Sciences, Beijing 100050, China.
Xu
Wei
W
Wang
Li
L
Jiang
Da-lin
DL
Li
Yun-zhuo
YZ