Dataset Information

Update on dermatophytosis in Mashhad, Northeastern Iran, emergence of infection with Trichophyton persicum.

ABSTRACT:

Background

Dermatophytosis is a common global superficial mycosis caused by a group of keratinophilic moulds known as dermatophytes that invade the skin and keratinized tissues such as hair and nails of humans and animals. This study takes identification of a collection of clinical dermatophyte isolates by using partial sequencing of translation elongation factor-1α (Tef-1α) gene aiming both to update the epidemiological status of dermatophytosis in Mashhad, Northeastern Iran and to corroborate the efficacy of Tef-1α for species-level identification of dermatophytes.

Method

The demographic data related to 87 culture-positive dermatophytes isolated from patients clinically suspected to have dermatophytosis were collected. The dermatophyte isolates were subjected to a partial polymerase chain reaction (PCR)-sequencing of Tef-1α gene by using specific pan-dermatophyte primers. The data were analysed by SeqMan software, the sequences were compared and aligned with the GenBank database and the isolates were identified.

Results

Identification based on Tef-1α partial sequence was successful for all isolates. The identified dermatophyte isolates in decreasing order were as Trichophyton interdigitale 19 (22%), T. tonsurans 19 (22%), T. mentagrophytes 13 (15%), T. persicum 10 (11.5%), Epidermophyton floccosum 9 (10.3%), Microsporum canis 7 (8%), T. rubrum 5 (5.7%), T. violaceum 2 (2.2%), Nannizzia fulva 2 (2.2%) and N. persicolor 1 (1.1%). The isolates have been associated with clinical forms of tinea corporis (n = 38; 43.7%), tinea faciei (n = 13; 15%), tinea cruris (n = 12; 13.9%), tinea manuum (n = 7; 8%), tinea unguium (n = 7; 8%), tinea capitis (n = 7; 8%) and tinea pedis (n = 3; 3.4%).

Conclusion

Dermatophytosis has yet remained a public health problem in Northeastern Iran, and infection with new and less frequent species, e.g., T. persicum, N. fulva and N. persicolor have emerged. The Tef-1α gene partial sequencing reconfirmed the resolution power of this locus for the determination of species boundaries in dermatophytes.

SUBMITTER: Afsharzadeh F

PROVIDER: S-EPMC9455102 | biostudies-literature | 2022 Mar-Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Update on dermatophytosis in Mashhad, Northeastern Iran, emergence of infection with <i>Trichophyton persicum</i>.

Afsharzadeh Fatemeh F Zarrinfar Hossein H Fata Abdolmajid A Najafzadeh Mohammad Javad MJ

Indian journal of dermatology 20220301 2

<h4>Background</h4>Dermatophytosis is a common global superficial mycosis caused by a group of keratinophilic moulds known as dermatophytes that invade the skin and keratinized tissues such as hair and nails of humans and animals. This study takes identification of a collection of clinical dermatophyte isolates by using partial sequencing of translation elongation factor-1α (<i>Tef-1α</i>) gene aiming both to update the epidemiological status of dermatophytosis in Mashhad, Northeastern Iran and ...[more]

PMID: 36092243

Similar Datasets

Project description:Dermatophytes are adapted to infect keratinized tissues by their ability to utilize keratin as a nutrient source. Although there have been numerous reports that dermatophytes like Trichophyton sp. secrete proteolytic enzymes, virtually nothing is known about the patterns of gene expression in the host or even when the organisms are cultured on protein substrates in the absence of a host. We characterized the expression of an aminopeptidase gene, the Trichophyton mentagrophytes homolog of the Trichophyton rubrum Tri r 4 gene. The T. rubrum gene was originally isolated based on the ability of the protein encoded by it to induce immediate and delayed-type hypersensitivity in skin tests. T. mentagrophytes Tri m 4 is closely related to Tri r 4 (almost 94% identity at the protein level). Tri m 4 resembles other protease-encoding genes thought to be virulence factors (for example, DPP V of Aspergillus fumigatus). The Tri m 4 protein was detected immunochemically both in fungal extracts and in the culture medium. Expression of the Tri m 4 gene was induced severalfold when T. mentagrophytes was grown on keratin and elastin. Ex vivo, strong induction was observed after culture on blood plasma, but the use of homogenized skin did not result in a significant increase in Tri m 4 transcript levels. In order to identify additional genes encoding putative virulence factors, differential cDNA screening was performed. By this method, a fungal thioredoxin and a cellulase homolog were identified, and both genes were found to be strongly induced by skin extracellular matrix proteins. Induction by superficial (keratin) and deep (elastin) skin elements suggests that the products of these genes may be important in both superficial and deep dermatophytosis, and models for their function are proposed. Upregulation of several newly identified T. mentagrophytes genes on protein substrates suggests that these genes encode proteins which are relevant to the dermatophyte-skin interaction.

Project description:Dermatophytes are agents of typically benign superficial infections. However, an increasing number of severe infections in immunocompromised hosts has been reported. We aimed to understand the factors underlying the existence of a cohort of patients presenting with chronic widespread dermatophytosis (CWD) due to Trichophyton rubrum, but with no signs of immunodeficiency. Their disease is usually recurrent and difficult to manage. Fourteen patients meeting the following criteria for CWD were studied: T. rubrum culture-proven skin lesions of ≥10 cm in at least one dimension; the involvement of at least three non-contiguous localizations of >1 year's duration; and no predisposing conditions. For comparison, we also studied 13 acute Tinea pedis patients. Macrophages and neutrophils were isolated and tested for T. rubrum conidia phagocytic and killing activity. H2O2, NO, and pro- and anti-inflammatory cytokine release were measured. All experiments were run with age- and sex-matched healthy donors' cells in parallel. CWD patients' macrophages and neutrophils presented with reduced T. rubrum-phagocytic and killing abilities, and reduced H2O2 and NO release when compared with those of healthy donors. CWD patients' macrophages secreted lower levels of the proinflammatory cytokines interleukin (IL)-1β, IL-6, IL-8, and tumor necrosis factor (TNF)-α, but enhanced levels of the anti-inflammatory cytokine IL-10. Neutrophil secretion closely followed this unbalanced pattern. In contrast, responses to the positive controls zymosan, lipopolysaccharide, and phorbol myristate acetate were comparable with those of healthy donors. The same experiments were performed with macrophages and neutrophils from the acute Tinea pedis patients and showed no differences when compared with the matched healthy donors. Patients with CWD have a T. rubrum-related functional deficiency of phagocytes and may represent a distinct clinical entity in the complex spectrum of the Trichophyton-host interaction.