Soil samples from sporotrichosis transmission belt area: Searching for fungal species and their antagonistic activity against Sporothrix brasiliensis.

Since 1998, the state of Rio de Janeiro, Brazil, has become a public health problem regarding sporotrichosis, a disease caused by Sporothrix spp. involving contact with infected cats. Efforts to isolate these species from environmental sources are not always successful. In our study, soil from residences situated in cities of Rio de Janeiro where cats with sporotrichosis live was collected and cultured an attempt to isolate Sporothrix spp. but it was not successful. However, other saprophytic fungal species were isolated from soil and identified and among them Purpureocillium lilacinum was the most frequent. From there, we decided to study the in vitro interaction of this species with S. brasiliensis, the principal agent that causes sporotrichosis in this state. The results showed that ten isolates of P. lilacinum inhibited the radial mycelial growth of S. brasiliensis with different percentage of inhibition. The interaction between them revealed the pattern described as overgrowth by antagonist. In conclusion, our data suggest that fungal species with very fast growth and capable of producing metabolites could hinder the growth of Sporothrix spp., it also opens the way for the identification of secondary metabolites with biological activity that could be tested against pathogenic fungi.

Advances and challenges in the management of feline sporotrichosis / Avances y desafíos en el manejo de la esporotricosis felina

The domestic cat is the most susceptible host to Sporothrix infection, developing severe clinical forms. Few effective antifungal agents are available for treating feline sporotrichosis, and cases of treatment failure are common. Treatment success depends on cat health status, therapy-related factors, as well as social/economic issues, but it is mainly contingent upon the host–fungus interaction. The owner's adherence is critical and should be reinforced throughout the treatment to increase the chances of a successful outcome. The antifungal agents described for feline sporotrichosis are most often used in monotherapy regimens. Due to cases in which the treatment with itraconazole failed, the use of antifungal agents in combination should be considered to achieve synergy. The combination of itraconazole and potassium iodide represents an important option for the treatment of naïve cats presenting multiple cutaneous lesions, nasal mucosal lesions and/or respiratory signs, as well as for refractory cases. However, the therapeutic options for unsuccessfully treated cases are scarce. Therefore new options are needed, even more taking into account that there are many in vitro potential molecules not available for use in cats yet. More studies are necessary to correlate in vitro antifungal susceptibility tests results and the outcome of cats treated due to sporotrichosis. This review will briefly discuss both the antifungal drugs and treatment protocols used in cats with sporotrichosis, as well as the determinants of treatment failure. (AU)

El gato doméstico es el huésped más susceptible a la infección por Sporothrix, llegando a desarrollar formas clínicas graves. Hay pocos agentes antimicóticos efectivos disponibles para tratar la esporotricosis felina, y los casos de fracaso terapéutico son habituales. El éxito del tratamiento depende del estado de salud del gato, los factores relacionados con la terapia y los problemas sociales/económicos, pero se asocia principalmente con la interacción huésped-hongo. El cumplimiento del tratamiento por parte del propietario es fundamental y debe reforzarse durante todo el proceso para aumentar las posibilidades de éxito. Los agentes antimicóticos descritos para la esporotricosis felina se usan con mayor frecuencia en monoterapia. Debido a los casos de fallo terapéutico en el tratamiento con itraconazol se debe considerar el uso combinado de agentes antifúngicos en sinergia. La combinación de itraconazol y yoduro de potasio es una buena opción en el caso de gatos no tratados previamente y con múltiples lesiones cutáneas, en la mucosa nasal y/o con signos respiratorios, así como para casos refractarios. Sin embargo, las opciones terapéuticas para la mayoría de los casos que fracasan son escasas. Por tanto, son necesarias nuevas opciones terapéuticas, más aún cuando existen muchas moléculas potenciales in vitro, no disponibles de momento para su uso en gatos. Son necesarios más estudios que correlacionen los resultados de las pruebas de sensibilidad in vitro a los antifúngicos con aquellos del tratamiento de gatos con esporotricosis. Esta revisión discutirá brevemente los fármacos antimicóticos y los protocolos terapéuticos utilizados para tratar gatos con esporotricosis, así como los factores determinantes del fracaso del tratamiento. (AU)