Isolation and Identification of Pathogenic Fungi from Thorns and Thistles in Isfahan and Adjacent Cities

The most important subcutaneous fungal infections in man are caused by injury due to contaminated thistles and thorns. From an epidemiological point of view , it is important to recognize the fungi as well as their frequency of them in various thistles and thorns

The present research has been conducted on thorns and thistles of 16 regions including cities and villages of Isfahan province. 800 samples have been collected. Specimens were inoculated and incubated at 25◦C in S & SCC medium. In order to isolate and identify the fungi, cultures in specific media, intraperitoneal injections of mice and disc diffusion test have been applied.

Over one year of study, 1676 colonies of actinomycetes and fungi were recognized. The most common fungi were as follows: Alternaria (22/4%),Aspergillus(11/8%) , Cladosporium (10/8%),Esteril mycellium(10/6%) and Penicillium (9/7%). The prevalence was most in Shahreza city(10/2%) , while the least was in Ardestan(3%). The most prevalent yeasts were Candida tropicalis (50%) , Rodotrula rubra (12/5%) , Candida kerusei(11/4%),Trichosporon candida (7/9%) , Unknown yeasts (6/8%), Candida gillermondi (5/7%), Saccharomyces cervisia (3/4%), Geotricum candidum and Trichosporon glabrata (Candida glabrata ) each one (1/1%). The prevalence was most in Khansar city(19/2%). In this study, 4 species similar to Coccidioides immitis, Phialophora verrucosa (4 species) and Exophiala jeanselmei (3 species) were identified.

In this study done for the first time in this area, pathogenic and opportunistic fungi were isolated. Furthermore, Exophiala jeanselmei and Nocardiopsis dassonvillei were isolated for the first time from thorns in the country.