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E-Book 2nd Congress

  • Evaluation of Antifungal Susceptibility Testing of 6 Antifungals Drugs against Resistance and Susceptible Aspergillus fumigatus by Microdilution Broth
  • Alam Ara Gholami,1 Ali Ahmadi,2,* Mahsan Azimidizaj,3 Sara Aqayi,4
    1. Assistant Professor, Department of Biological Sciences and Technologies, Islamic Azad University, Sari Branch, Sari, Iran
    2. M.Sc. Student, Department of Genetics, Faculty of Advanced Technologies and Science in Medicine, Islamic Azad University Tehran Medical Science, Tehran, Iran
    3. M.Sc. Student, Department of Genetics, Faculty of Basic Science, Islamic Azad University Tabriz Branch, Tabriz, Iran
    4. B.Sc. Student, Department of Surgical Technology, Islamic Azad University Malayer Branch, Malayer, Iran


  • Introduction: In recent years, Aspergillosis infections have increased dramatically and, unfortunately, this disease causes many deaths in hospitals. Invasive aspergillosis is a severe and fatal fungal infection that is observed in immunocompromised patients, neutropenia, chronic granulomatosis, hematologic malignancies, bone marrow transplant recipients, stem cells and other tissues and people using long-term antibiotics and Steroids. Aspergillus fumigatus is the most common cause of Aspergillosis infection and is of increasing importance in the medical field, but other species such as Aspergillus flavus, Aspergillus niger and Aspergillus terreus are also important in this regard. Most high-risk patients with susceptible background to invasive Aspergillosis infection and post-clinical infection can be identified after treatment of underlying disease during hospitalization. Although the number of drug agents with anti-aspergillus activity has increased in the past decade, mortality due to invasive Aspergillosis is unexpectedly increasing. Increasing resistance of Aspergillus species to antifungal drugs in the past 20 years has led to an increase in therapeutic failures. This study aimed, Determination of A. fumigatus species isolated from clinical and environmental samples using molecular methods (DNA sequencing) and evaluation of medicinal sensitivity of A. fumigatus species isolated from environmental and clinical samples against common drugs (Amphotericin B, Voriconazole, Itraconazole, Posaconazole , Caspofungin. and Micafungin)
  • Methods: The present study was conducted in 2021-2022 during a one-year period by examining environmental and clinical samples of A. fumigatus species that had been previously isolated and confirmed by amplification and sequencing of the B-tubulin gene region. Susceptibility patterns of antifungal drugs such as Amphotericin B, Itraconazole, Voriconazole, Posaconazole, Caspofungin and Micafungin were determined against isolates identified by CLSI method, M38-A2 protocol for stranded fungi.
  • Results: A total of 103 isolated Aspergillus fumigatos (30 clinical and 73 environmental samples) were identified. Based on morphological characteristics and confirmation of molecular method, they were identified. A. fumigatus was the most susceptible to antifungal drugs Posaconazole, Voriconazole, Micafungin and Caspofungin. However, most species of A. fumigatus in MIC50 and MIC90 were resistance to drugs, Itraconazole, and Amphotericin B. However, in the case of Amphotericin B and Itraconazole, resistances have been observed that should be considered in the treatment of these drugs. Considering that successful treatment depends on rapid identification of the species and its susceptibility pattern to antifungal drugs, therefore, accurate identification of the cause of the disease and investigation of new and old drug sensitivities profiles on isolated strains from clinical samples can be used for rapid treatment of this type of drug. Aspergillosis is a severe and fatal fungal infection that is observed in immunocompromised patients, neutropenia, chronic granulomatosis, hematologic malignancies, bone marrow transplant recipients, stem cells and other tissues and people using long-term antibiotics and steroids, Aspergillus fumigatus is the most common cause of Aspergillosis infection, often under certain conditions in susceptible individuals. The risk to the deep tissues of this species is of increasing importance in the medical field, but other species such as Aspergillus flavus, Aspergillus niger, Aspergillus terreus are also important in this regard. Successful therapeutic management of invasive Aspergillosis depends on the early onset of treatment, the selection of an effective antifungal drug and the lack of resistance of the fungus to it. In these patients, treatment should be started quickly and after suspecting the disease and continue until full recovery. There are different methods for determining fungal species, among which molecular methods have special attention due to their high speed and accuracy. Infections and avoid spending extra money and unsuccessful treatments are very useful. To confirm the diagnosis of Aspergillus fumigatus isolates isolated from plates containing Saboro dextrose agar, DNA of the samples after extraction was amplified using primers of beta-tubulin gene region and sequenced by sequencing method. The results of sequencing for these products after matching the sequences in the gene bank using BLAST software, based on Coverage Query and Max identity, clearly identified Aspergillus species.
  • Conclusion: According to the results of this study, it can be concluded that Voriconazole, Caspofungin, Micafungin and Posaconazole have a good effect on A. fumigatus species and due to low concentrations of MIC in Caspofungin and Posaconazole, these two drugs are effective in the treatment of Aspergillosis and are used.
  • Keywords: A. fumigatus, Antifungal, Susceptibility, Microdilution Drug, Iran