Erick Martínez-Herrera

The habitat of Coccidioides spp. and the role of animals as reservoirs and disseminators in nature

BackgroundCoccidioidomycosis, a potentially fatal fungal infection, is considered an emergent mycotic disease because of the increased incidence of fungal infections registered over recent years. Infection occurs through the inhalation of arthroconidia from two main species of Coccidioides: Coccidioides immitis and C. posadasii, which are both endemic to arid and semi-arid regions of North America. Coccidioides species not only infect humans but can also infect other mammals (land, aquatic, wild or domestic), reptiles and birds.ObjectiveTo obtain information regarding the habitat of Coccidioides spp. and the animals infected by this fungus and to identify the role that infected animals play as reservoirs and disseminators of this fungus in nature.MaterialsA literature review was conducted to identify the habitat of Coccidioides spp. and the infected non-human animal species targeted by this fungus.Results and conclusionsThis review allows us to suggest that Coccidioides spp. may be classified as halotolerant organisms; nevertheless, to perpetuate their life cycle, these organisms depend on different animal species (reservoirs) that serve as a link with the environment, by acting as disseminators of the fungi in nature.

Tiña incógnita y granuloma de Majocchi adquirido de un erizo. Un caso mexicano

Exotic pets, such as the ground hedgehog, are capable of transmitting to the human being different zoonoses, such as salmonellosis, mycobacteria, protozoa such as Cryptosporidium parvum, and dermatophytosis. We present the case report of a male adult patient, who had recently acquired a ground hedgehog, who presented in his hand a ringworm lesion incognito and a Majocchi granuloma. The etiological agent was identified as Trichophyton erinacei by mycological culture and molecular biology. The patient was treated with terbinafine oral, with excellent response.

Onychomycosis Due to Aspergillus spp.: a Current Review

Purpose of ReviewThe incidence of onychomycosis by Aspergillus has shown an increase in recent years, representing 34–60% of onychomycosis due to non-dermatophyte molds. At least 26 species of Aspergillus causing onychomycosis have been reported, some of which may be morphologically indistinguishable but genetically distinct, even in their susceptibility profile to antifungals. So in the diagnosis of this pathology, it is necessary to use both conventional and molecular methods to get to the identification of the fungus at the species level and thus establish the appropriate treatment.Recent FindingsThe current taxonomy of the genus Aspergillus includes sections that are made up of species whose morphology is almost identical but have different patterns of susceptibility to antifungals. Advances in the taxonomy of these fungi reveal the need to combine phenotypic methods (analysis of microscopic and macroscopic characteristics) with molecular ones (amplification and sequencing of fragments of the β-tubulin and calmodulin genes) to achieve their correct identification at the level of species.SummaryFrom the demonstration of Aspergillus as the primary agent of onychomycosis, an increase in the incidence of this pathology worldwide has been reported, whose treatment is usually complicated. Various species of Aspergillus can cause nail infection but may respond differently to antifungal treatment, so it is important to know their epidemiology, clinical characteristics, etiologic agents, diagnostic methods, and treatment.

Current status of the etiology of candidiasis in Mexico

This study presents a systematic review of the literature on the etiology of superficial and invasive candidiasis in Mexico reported from 2005 to 2015. The data have shown that Candida albicans is the most prevalent species with an increasing tendency of the non-C. albicans Candida species, as reported in other countries. The use of phenotypical methods in the identification of the yeasts limits the identification at the species level, particularly in species that are part of complexes, this is important because the identification only at the genus level leads to inadequate treatment due to the different susceptibility to the antifungals among species. In addition, this finding reveals the need to implement in clinical laboratories the molecular methods for the correct identification of the species involved, and the antifungal susceptibility tests to prevent the etiological changes associated with a poor therapeutic management.

Dermatophytes and Dermatophytosis

Dermatophytosis, are the most common fungal infection worldwide. Transmission is mostly by direct contact with infected animals, humans or contact with fomites. Clinical features vary according to the etiological agent. Dermatophytes belong to the genera Microsporum, Trichophyton, Epidermophyton (anamorphic state), and Arthroderma (teleomorphic state). The main etiological agents in humans are T. rubrum, T. tonsurans, T. mentagrophytes complex, and M. canis, M. gypseum, and E. floccosum. Recent phylogenetic studies indicate the existence of a fourth genus, Chrysosporium. In this chapter we analyze epidemiology, biology, clinical forms, pathogenesis, diagnosis, detection methods and treatment. Also molecular taxonomy, molecular epidemiology, molecular techniques, molecular identification and treatment are widely analyzed.