Introduction: Trichophyton mentagrophytes and T. interdigitale are important causative agents of superficial mycoses, demonstrating emergent antifungal drug resistance. We studied the antifungal susceptibility profiles in Iranian isolates of these two species. Methods: A total of 96 T. interdigitale and 45 T. mentagrophytes isolates were subjected to molecular typing by ribosomal ITS region. Antifungal susceptibility profiles for terbinafine, griseofulvin, clotrimazole, efinaconazole, luliconazole, amorolfine and ciclopirox were obtained by CLSI broth microdilution method. The squalene epoxidase (SQLE) gene was subjected to sequencing for mutations, if any, in isolates exhibiting elevated MICs for terbinafine. Results: Luliconazole and efinaconazole showed the lowest MIC values against T. mentagrophytes and T. interdigitale isolates. There were five isolates with terbinafine MICs ≥32 µg/mL in our sample. They belonged to T. mentagrophytes type VIII and harbored two alternative SQLE gene sequence variants, leading to Phe397Leu and Ala448Thr or Leu393Ser and Ala448Thr substitutions in the enzyme. All terbinafine resistant strains could be inhibited by luliconazole and efinaconazole. Conclusion: This study documented a step in the global spread of resistance mechanisms in T. mentagrophytes. However, treatment alternatives for resistant isolates were available.

Summary The fungi Trichophyton mentagrophytes and T interdigitale account for significant amount of dermatophytosis cases worldwide. These two dermatophytes form a species complex and have a number of ribosomal internal transcribed spacer (ITS) region genotypes, allowing simultaneous species identification and strain typing. Our aim was to describe the geographic distribution of T mentagrophytes/T interdigitale ITS region genotypes and find an association between the genotypes and clinical presentations of respective infections. We performed rDNA ITS region sequencing in 397 Iranian T mentagrophytes/T interdigitale isolates and analysed all available in GenBank entries with sequences of this kind. For the study, 515 clinical annotations were available. Statistical analysis was performed by chi‐squared test and Spearman rank correlation analysis. A total of 971 sequences belonged to genotypes with at least 10 geographic annotations and were classified on the basis of exclusive occurrence in a particular region or high relative contribution to a regional sample. We discerned Asian and Oceanian (“” Type V, “” Type VIII, “”), European (“” Type III, “” Type III*, “” Type VI) and cosmopolitan (“” Type I, “” Type II, “” Type II* and “” Type XXIV) genotypes. There was statistically significant difference in the ITS genotype distribution between different affected body sites. Trichophyton mentagrophytes “” Type VIII correlated with tinea cruris, T mentagrophytes “” Type V correlated with tinea corporis, T interdigitale “” Type II correlated with tinea pedis and onychomycosis. Trichophyton mentagrophytes and T interdigitale genotypes can be associated with distinct geographic locations and particular clinical presentations.

Dermatophytosis is a common mycotic infection of the skin, nail, and hair, associated with major public health concern worldwide. Various species of dermatophytes show significant differences in susceptibility to antifungals. Here, we present the antifungal susceptibility of a large collection of molecularly identified dermatophyte isolates obtained from tropical region of south of Iran. A total of 9485 patients clinically suspected to have cutaneous fungal infections were examined. Dermatophytosis was confirmed in 1502 cases by direct microscopy and culture. Three hundred and sixteen isolates recovered in culture were identified to species level using PCR sequencing of ITS region and RFLP. Tinea corporis was the most prevalent type of clinical manifestation (35.2 %), followed by tinea cruris (17 %), tinea capitis (12.8 %), tinea pedis (11.3 %), tinea manuum (11 %), tinea unguium (6.9 %), and tinea barbae (5.8 %). Trichophyton interdigitale was the most common isolate (49.36 %), followed by Trichophyton rubrum (18.98 %), Epidermophyton floccosum (13.29 %), Microsporum canis (9.17 %), Arthroderma benhamiae (T. anamorph of A. benhamiae; 5.38 %), and Trichophyton tonsurans (3.79 %). Overall, irrespective of the geographical region, terbinafine was the most potent antifungal against all isolates, with an MIC range of 0.002-0.25 μg/mL, followed by itraconazole (0.004-0.5 μg/mL), griseofulvin (0.125-8 μg/mL), and fluconazole (4-128 μg/mL). Analysis of our data revealed a significant increase in the frequency of A.benhamiae, which definitely warrants further investigation to explore source of this infection in south of Iran. Moreover, terbinafine was the most effective antifungal against all isolates, in vitro.

Azole resistance in Aspergillus is emerging in European and Asian countries. As azoles are mainstay of therapy in the management of aspergillosis, azole resistance has serious implications in patient management. We report the emergence of resistance to triazoles in environmental Aspergillus fumigatus isolates in Iran. The TR34/L98H mutation was the only resistance mechanism. Overall 3.3% of the A. fumigatus isolates from hospital surroundings in Sari and Tehran had the same TR34/L98H STRAf genotype and were related to some resistant clinical and environmental TR34/L98H isolates from the Netherlands and India. It is emphasised that routine resistance surveillance studies focusing on environmental and clinical samples are warranted to yield the true prevalence of azole resistance in A. fumigatus in Iran.

Inflammatory bowel disease (IBD) is a multi‐factorial autoimmune disorder that its causative agents are unknown. The gut microbiota comprises of bacteria, viruses, fungi and protozoa that its role in IBD has remained controversially. Bacteria constitute more than 99% of the gut microbiota composition, and the main core of the gut microbiota is composed from Bacteroidetes and Firmicutes. The gut microbiota plays an important role in training, development and haemostasis of the immune responses during the life. Fungi compose a very small portion of gut microbiota, but play determinative roles in homeostasis of the gut bacterial composition and the mucosal immune responses. An interkingdom correlation between bacteria and fungi has been suggested. For example, the presence of Salmonella enterica serovar Typhimurium reduces the viability and colonisation of C albicans. Alterations in the composition and function of the gut microbiota, which is known as dysbiosis, are a usual event in patients who suffer from IBD. Although the main reason for this alteration is not clear, the interaction between gut bacteria and gut fungi seems to be an important subject in IBD patients. This review covers new findings on the interaction between fungi and bacteria and the role of fungi in the pathophysiology of IBD.