Laser irradiation on growth of trichophyton rubrum: an in vitro study

Trichophyton rubrum is one of the most common species of dermatophytes which affects superficial keratinous tissue. It is not especially virulent but it can be responsible for considerable morbidity. Although there are different therapeutic modalities to treat fungal infections, clinicians are searching for alternative treatment because of the various side effects of the present therapeutic methods. As a new procedure, Laser therapy has brought on many advantages in clinical management of dermatophytes. Possible inhibitory potential of laser irradiation on fungal colonies was investigated invitro in this study. A total of 240 fungal plates of standard size of trichophyton rubrum colonies that had been cultured from the lesions of different patients at the mycology laboratory, were selected. Each fungal plate was assigned as control or experimental group. Experimental plates were irradiated by a laser system [low power laser or different wavelength of high power laser]. The effects of different laser wavelengths and energies on isolated colonies were assessed. After laser irradiation, final size of colonies was measured on the first, the 7[th] and the 14[th] day after laser irradiation. Although low power laser irradiation did not have any inhibitory effect on fungal growth, the Q-Switched Neodymium-Doped Yttrium Aluminium Garnet [Nd:YAG] laser 532nm at 8j/cm[2], Q-Switched Nd:YAG laser 1064nm at 4j/cm[2] to 8j/cm[2] and Pulsed dye laser 595nm at 8j/cm[2] to 14j/cm[2] significantly inhibited growth of trichophyton rubrum in vitro. Q-Switched Nd:YAG 532nm at 8j/cm[2], Q-Switched Nd:YAG laser 1064nm at 4j/cm[2] to 8j/cm[2] and pulsed dye laser [PDL] 595nm at 8j/cm[2] to 14j/cm[2] can be effective to suppress trichophyton rubrum growth

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, ciclopiroxolamine, 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.eriotriphon and Arthrodermabenhamiae. The mean number of fungi particles [conidia] inoculated was 1.25 x 10[4] 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

molecular epidemiological survey of clinically important dermatophytes in Iran based on specific RFLP profiles of betatubulin gene

Surveillance of dermatophytosis is essential to determine the likely changes in etiological trends and distribution profile of this infection. In this study beta tubulin gene [BT2], was used as the first time in a PCR-RFLP format to clarify the distribution of dermatophytosis agents in some parts of Iran. A total of 603 clinical isolates was obtained from 500 patients in Tehran, Isfahan, Mazandaran and Guilan provinces. The isolates were identified using macro/micro-morphological criteria and electrophoretic patterns of PCR amplicons of BT2 after digestion with each of the restriction enzymes. FatI, Hpy CH4V, MwoI and Alw21L. Among the patients, 59.2% were male and 40.8% female. The most prevalent clinical form was tinea pedis [42.4%], followed by tinea cruris [24.2%], tinea unguium [12.3%], tinea corporis [10.8%], tinea faciei [4%], tinea manuum [3.14%], tinea capitis [3%] and tinea barbae [0.16%], respectively. Trichophyton interdigitale ranked the first, followed by T.rubrum, Epidermophyton floccosum, Microsporum canis, T. tonsurans, T. erinacei and T. violaceum [each 0.49%] and the less frequent species were T. schoenleinii, M. gypseum and T. anamorph of Arthroderma benhamiae [each 0.16%]. A case of scalp infection by E. floccosum was an exceptional event in the study. No case of T.verrucosum was found. Trichophyton species and E. floccosum are yet the predominant agents of infection in Iran, while Microsporum species are decreasing. T.interdigitale and Tinea pedis remain as the most causal agent and clinical form of dermatophytosis, respectively. it seems that BT2 can be a useful genetic marker for epidemiological survey of common pathogenic dermatophytes

[Identification of pathogenic yeasts isolated from onychomycosis in Tehran, using polymerase chain reaction and enzymatic digestion]

Fungal nail infection [onychomycosis] is a common disease in all communities consisting about 50 percent of nail disorders. Yeasts are one of the important causative agents of onychomycosis. Identification of the yeast species is important in the epidemiological and therapeutical point of views. The aim of the present study is the precise species identification of the pathogenic yeast isolated from fungal nail infections, using the DNA-based methods. The isolates were preliminary studied according to study of morphological characteristics. For species identification, the genomic DNA of each sample was extracted by boiling method and the ITS region of ribosomal DNA was amplified by polymerase chain reaction [PCR]. The amplified DNA was digested by the restriction enzyme MspI and each isolate was identified according to the electrophoretic patterns. A new enzymatic profile was used for final differentiation of Candida albicans and C. dubliniensis. A few of yeast isolates were identified by using ITS-sequensin. C. albicans with the prevalence of 45.6% was the most common isolate, followed by C. parapsilosis with 22.5% and C. tropicalis with 21.8%. The less common species were C. glabrata, C. krusei, C. kefyr, C. lusitaniae, C. guilliermondii and C. pulcherrima that consisted 2.72%, 2%, 1.36%, 0.68% and 0.68% of the isolates, respectively. No C. dubliniensis was found among C. albicans isolates. Two isolates [1.36%] were identified as Trichosporon spp. The most common group of the patients was in the age range of 40-70 years old and the majority [83.2%] of the patients were women with finger nail infections. Although C. albicans is still the most prevalent isolates of nail candidiasis, the increasing number of non-albicans species is notable. The study showed that for identification of some rare species, the routine phenotypical approaches are not efficient and application of the ITS-PCR-RFLP can improve the level of differentiation up to 98%. The remaining isolates can be identified by more expensive methods such as sequencing