Fungal infections in animals: a patchwork of different situations.

The importance of fungal infections in both human and animals has increased over the last decades. This article represents an overview of the different categories of fungal infections that can be encountered in animals originating from environmental sources without transmission to humans. In addition, the endemic infections with indirect transmission from the environment, the zoophilic fungal pathogens with near-direct transmission, the zoonotic fungi that can be directly transmitted from animals to humans, mycotoxicoses and antifungal resistance in animals will also be discussed. Opportunistic mycoses are responsible for a wide range of diseases from localized infections to fatal disseminated diseases, such as aspergillosis, mucormycosis, candidiasis, cryptococcosis and infections caused by melanized fungi. The amphibian fungal disease chytridiomycosis and the Bat White-nose syndrome are due to obligatory fungal pathogens. Zoonotic agents are naturally transmitted from vertebrate animals to humans and vice versa. The list of zoonotic fungal agents is limited but some species, like Microsporum canis and Sporothrix brasiliensis from cats, have a strong public health impact. Mycotoxins are defined as the chemicals of fungal origin being toxic for warm-blooded vertebrates. Intoxications by aflatoxins and ochratoxins represent a threat for both human and animal health. Resistance to antifungals can occur in different animal species that receive these drugs, although the true epidemiology of resistance in animals is unknown, and options to treat infections caused by resistant infections are limited.

Molecular identification and phylogenetical analysis of dermatophyte fungi from Latin America.

Dermatophytes constitute a complex group of fungi, comprised of by the genera Trichophyton, Epidermophyton and Microsporum. They have the ability to degrade keratin and cause human and animal infections. Molecular techniques have made their identification faster and more accurate, and allowed important advances in phylogenetic studies. We aim to identify molecularly and to determine the phylogenetic relationships in dermatophyte fungi from Brazil and other Latin American countries, using DNA sequencing of the nuclear ribosome regions ITS1-5.8S-ITS2 and D1/D2. DNA of 45 dermatophytes was extracted and amplified by PCR for identification at the species level by sequencing of those ribosomal regions. The software mega 6.0 was used to establish the phylogenetic relationships via the Maximum Likelihood method. Out of 45 strains, 43 were identified by ITS (95.5%) and 100% by D1/D2 sequencing. Two strains could not be identified by ITS. Phylogenetic analyses separated the genera Trichophyton and Microsporum, which presented an uncertain relationship with Epidermophyton floccosum, depending on the ribosomal marker. Both regions can provide efficient identification of dermatophytes, whereas phylogenetic analysis revealed complex relations among dermatophyte fungi.

Photodynamic therapy for pythiosis.

BACKGROUND: Pythiosis is a life-threatening disease caused by Pythium insidiosum. Photodynamic therapy (PDT) is an alternative treatment to surgery that uses the interaction of a photosensitizer, light and molecular oxygen to cause cell death. OBJECTIVES: To evaluate the effect of PDT on the in vitro growth of P. insidiosum and in an in vivo model of pythiosis. METHODS: For in vitro studies, two photosensitizers were evaluated: a haematoporphyrin derivative (Photogem(®)) and a chlorine (Photodithazine(®)). Amphotericin B was also evaluated, and the control group was treated with sterile saline solution. All experiments (PDT, porphyrin, chlorine and light alone, amphotericin B and saline solution) were performed as five replicates. For in vivo studies, six rabbits were inoculated with 20,000 zoospores of P. insidiosum, and an area of 1 cm(3) was treated using the same sensitizers. The PDT irradiation was performed using a laser emitting at 660 nm and a fluence of 200 J/cm(2) . Rabbits were clinically evaluated daily and histopathological analysis was performed 72 h after PDT. RESULTS: For in vitro assays, inhibition rates for PDT ranged from 60 to 100% and showed better results in comparison to amphotericin B. For the in vivo assays, after PDT, histological analysis of lesions showed a lack of infection up to 1 cm in depth. CONCLUSIONS AND CLINICAL IMPORTANCE: In vitro and in vivo studies showed that PDT was effective in the inactivation of P. insidiosum and may represent a new approach to treating pythiosis.