Molecular identification and azole susceptibility testing of Aspergillus section Fumigati isolated from soil samples in Lebanon


Aspergillus fumigatus is a human pathogen and a widespread fungus in the environment. This fungus produces airborne spores, which are inhaled by humans, and can cause a range of diseases including allergic syndromes, chronic pulmonary infections or acute invasive infections in immunocompromised patients. A limited number of antifungal drugs are available for treatment, such as azoles which are generally effective and considered as the first line drugs used in the prophylaxis and treatment of Aspergillus diseases. However, azole-resistance has been recorded worldwide, threatening current treatment options. Azole-resistance can develop in A. fumigatus sensu stricto either through azole exposure during therapy or in the environment, after exposure to azole fungicides, and has been reported in clinical and environmental samples in many countries with varying prevalences. In the Middle Eastern countries, A. fumigatus azole-resistant strains have been reported in Turkey, Iran, and Kuwait. In Lebanon, a recent study has examined 73 Aspergillus isolates recovered mostly from patients with ear infections. The predominant species was A. niger (54.8%), followed by A. flavus (27.4%), and A. tubingensis (5.4%), whereas A. fumigatus represented only 4.1% of the isolates. Susceptibility testing revealed an overall high frequency of antifungal resistance. Two A. fumigatus isolates presented elevated azole minimal inhibitory concentration values (MICs), but underlying mechanisms were not explored. Therefore, data regarding A. fumigatus azole-resistance in clinical samples remains limited in Lebanon, and the occurrence of resistance remains unknown in the environment. In this study, we sought to assess the prevalence and mechanisms of Aspergillus section Fumigati azole-resistance in environmental samples in North Lebanon through collection of soil samples from selected areas.

Journal/Conference Information

Journal of Medical Mycology,DOI:, Volume: 32, Issue: 2, Pages Range: 3-7,