Isolation and molecular characterization of clinical and environmental dematiaceous fungi and relatives from Iran.

Background and Purpose: The frequency and genetic diversity of black fungi in environmental and clinical settings have not been fully studied in Iran. This study aimed to identify and evaluate intra- and inter-species DNA sequence variation and also understand the phylogenetic relationships of melanized fungi and relatives isolated from different geographical regions of Iran. Materials and Methods: In total, 111 clinical and environmental strains of dematiaceous fungi were isolated, and their internal transcribed spacer ribosomal DNA (rDNA) regions were sequenced and analyzed. Results: An inter-species nucleotide sequence diversity rate of 1 to 464 nucleotides was observed between the species. Intra-species differences were found in the strains of Alternaria alternata, Cladosporium cladosporioides, Alternaria tenuissima, Curvularia spicifera, Aureobasidium pullulans, Curvularia hawaiiensis, Neoscytalidium dimidiatum, Alternaria terricola, Alternaria chlamydospora, Didymella glomerata, and Drechslera dematioidea by 0-59, 0-22, 0-4, 0-4, 0-3, 0-2, 0-2, 0-2, 0-2, 0-1, and 0-1 nucleotide, respectively. Conclusion: The internal transcribed spacer rDNA is useful for the discrimination of several taxa of dematiaceous fungi. However, a better understanding of the taxonomy of species of Alternaria requires a larger rDNA region or a library of other gene sequences.

Pulmonary nocardiosis associated with cerebral abscess successfully treated by co-trimoxazole: a case report.

Nocardiosis is an acute or chronic infectious disease caused by the soil-borne filamentous bacteria belonging to the genus Nocardia. The organisms opportunistically infect both immunocompromised and immunocompetent individuals. The lungs are the primary site of infection and brain abscess is, by far, the most common complication following nocardial metastasis from pulmonary lesions. Although surgical intervention must always be considered in the treatment of nocardial brain abscess, it can obviously be cured by antibiotic therapy alone. This report describes a case infected by Nocardia cyriacigeorgica. Identification of the infectious agent was achieved by conventional and semi-nested PCR techniques. A 55-year-old woman with fever was referred to the infect disclinic of Imam Khomeini hospital in Tehran and was hospitalized after clinical assessment. She was a kidney transplant recipient for 4 years and was taking immunosuppressive treatment including azathioprine and methylprednisolone. Follow-up of the patient by CT scan revealed pulmonary infection and cerebral lesions. Specimens of the brain lesions contained filamentous bacteria. The patient received a combination of co-trimoxazole and ceftriaxone and brain abscesses as well as lung inflammation disappeared gradually during the course of antibiotic therapy within 3 months. The patient was discharged from the hospital after 2 months of therapy.

In-vitro Activity of 10 Antifungal Agents against 320 Dermatophyte Strains Using Microdilution Method in Tehran.

Dermatophyte fungi are the etiologic agents of skin infections commonly referred to as ringworm. These infections are not dangerous but as a chronic cutaneous infections they may be difficult to treat and can also cause physical discomfort for patients. They are considered important as a public health problem as well. No information is available regarding the efficacy of antifungal agents against dermatophytes in Tehran. Therefore, in this study we evaluated the efficacy of 10 systemic and topical antifungal medications using CLSI broth microdilution method (M38-A). The antifungal agents used included griseofulvin, terbinafine, itraconazole, ketoconazole, fluconazole, voriconazole, clotrimazole, ciclopirox olamine, amorolfine and naftifine.Fifteen different species of dermatophytes which were mostly clinical isolates were used as follows; T. mentagrophytes, T. rubrum, E. floccosum, M. canis, T. verrucosum, T. tonsurans, M. gypseum, T. violaceum, M. ferruginum, M. fulvum, T. schoenleinii, M. racemosum, T. erinacei, T. eriotrephon and Arthroderma benhamiae. The mean number of fungi particles (conidia) inoculated was 1.25 ×104 CFU/mL. Results were read after 7 days of incubation at 28 °C. According to the obtained results,itraconazole and terbinafine showed the lowest and fluconazole had the greatest MIC values for the most fungi tested. Based on the results, it is necessary to do more research and design a reliable standard method for determination of antifungal susceptibility to choose proper antibiotics with fewer side effects and decrease antifungal resistance and risk of treatment failure.