Vaezi Afsane, Walther Grit, Kurzai Oliver, Mahdi Diman, Dadashzadeh Mina, Nasri Elahe, Diba Kambiz, Badali Hamid, Fakhim Hamed
Department of Medical Laboratory Science, School of Allied Medical Sciences, Iran University of Medical Sciences, Tehran, Iran.
German National Reference Center for Invasive Fungal Infections, Leibniz Institute for Natural Product Research and Infection Biology - Hans Knöll Institute, Jena, Germany.
Mycoses. 2021 Jul;64(7):780-787. doi: 10.1111/myc.13283. Epub 2021 Apr 26.
Mucorales are opportunistic pathogens that can cause life-threatening diseases predominantly in immunocompromised patients.
This study aimed to investigate the frequency, seasonal variation and antifungal susceptibility of pathogenic Mucorales in the soil collected from seven hospitals in Urmia, Iran, between November 2017 and July 2018 in four different seasons.
Mucorales isolates obtained from soil were characterised based on conventional and molecular assays. In addition, in vitro antifungal susceptibility was performed using the CLSI M38Ed3 procedure.
Out of 196 tested soil samples, 80 (40.8%) samples were positive for mucoralean fungi. Rhizopus arrhizus var. arrhizus (n = 47) was the most frequent species followed by Mucor circinelloides (n = 21) and Cunninghamella echinulata (n = 6). A seasonal variation in the frequency of Mucorales in soil was detected with a maximum of culture-positive soil samples detected in wet autumn (43.2%) followed by winter (23.4%), summer (19.7%) and spring (13.6%). In vitro antifungal susceptibility testing for 80 environmental isolates exhibited MIC of ≤2 μg/ml for amphotericin B indicating the smallest range of MIC variation among the tested Mucorales (range: 0.125-2 μg/ml). Among the azoles, posaconazole was the most effective antifungals (GM MIC, 0.724 μg/ml).
We considered associations of species and seasonal frequencies between soil mucoralean fungi and mucormycosis. The effect of opportunistic Mucorales dominating in the soil and prevalent causative agents of mucormycosis in Iran reported in the literatures but more comprehensive studies are needed to confirm this conclusion.
毛霉目真菌是机会性致病菌，主要在免疫功能低下的患者中引起危及生命的疾病。
本研究旨在调查2017年11月至2018年7月期间在伊朗乌尔米耶的七家医院采集的土壤中致病毛霉目的频率、季节变化及抗真菌药敏情况，共涉及四个不同季节。
从土壤中分离得到的毛霉目菌株通过传统和分子检测方法进行鉴定。此外，采用CLSI M38Ed3方法进行体外抗真菌药敏试验。
在196份受试土壤样本中，80份（40.8%）样本毛霉目真菌呈阳性。少根根霉变种少根根霉（n = 47）是最常见的菌种，其次是卷枝毛霉（n = 21）和刺孢小克银汉霉（n = 6）。检测到土壤中毛霉目的频率存在季节变化，秋季潮湿时培养阳性的土壤样本最多（43.2%），其次是冬季（23.4%）、夏季（19.7%）和春季（13.6%）。对80株环境分离株进行的体外抗真菌药敏试验显示，两性霉素B的MIC≤2μg/ml，表明在所检测的毛霉目中MIC变化范围最小（范围：0.125 - 2μg/ml）。在唑类药物中，泊沙康唑是最有效的抗真菌药（GM MIC，0.724μg/ml）。
我们考虑了土壤中毛霉目真菌与毛霉病之间的菌种关联及季节频率。文献报道了伊朗土壤中占主导地位的机会性毛霉目真菌与毛霉病常见病原体之间的关系，但需要更全面的研究来证实这一结论。
