Phenotypic and molecular characterization and antifungal susceptibility profile of clinical isolates of Sporothrix schenckii complex obtained from dogs and cats from the state of Rio de Janeiro

Autor: Abreu, Daniel Paiva Barros de
Přispěvatelé: Baroni, Francisco de Assis, Coelho, Irene da Silva, Pereira, Sandro Antonio, Cruz, Luiz Celso Hygino da
Jazyk: portugalština
Rok vydání: 2017
Předmět:
Zdroj: Biblioteca Digital de Teses e Dissertações da UFRRJ
Universidade Federal Rural do Rio de Janeiro (UFRRJ)
instacron:UFRRJ
Popis: Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2017-09-13T12:31:48Z No. of bitstreams: 1 2017 - Daniel Paiva Barros de Abreu.pdf: 1307092 bytes, checksum: b384d4db2cb316d3f640b111bc8efba4 (MD5) Made available in DSpace on 2017-09-13T12:31:48Z (GMT). No. of bitstreams: 1 2017 - Daniel Paiva Barros de Abreu.pdf: 1307092 bytes, checksum: b384d4db2cb316d3f640b111bc8efba4 (MD5) Previous issue date: 2017-02-20 CNPq - Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico Dimorphic fungi belonging to Sporothrix schenckii complex are responsible for sporotrichosis, important fungal infection with worldwide distribution. The anthropozoonotic characteristic is of high relevance in the state of Rio de Janeiro, where an increasing in the number of cases in human patients was observed in the last decades, highlighting the role of domestic cat as a transmitter agent. The description of new species compounding de Sporothrix genus, based on phenotypic and genotypic evaluations, showed the involvement of other members of this group in the epidemic status installed in Rio de Janeiro. The verification of strains resistant to itraconazole, a widely used antifungal in human and animal medicine for the treatment of this mycosis, is an important factor that possibly results in relapse and therapeutic failure of this disease. The present study aimed to identify, by phenotypic and molecular approaches, 168 isolates obtained from the routine of Veterinary Clinical Microbiology Laboratory ? UFRRJ, and the determination of minimal inhibitory concentration (MIC) for amphotericin B (AMB), ketoconazole (KTC), itraconazole (ITC), terbinafine (TRB) and voriconazole (VRC). Based on morphophysiological characteristics it was possible to identify 159 (94.64%) isolates as S. brasiliensis and 9 (5.36%) as S. luriei. However, applying PCR-RFLP of calmodulin 168 (100%) samples were identified as S. brasilensis. The susceptibility test, based on M38-A2 document (CLSI), showed that TRB was the most effective antifungal tested, followed by ITC, KTC, AMB, and VRC, respectively. No ITC resistant isolates were detected in the present study. These results demonstrate that the identification reached only by phenotypic evaluation is not recommended for the characterization of Sporothrix schenckii complex components. It also proves the predominance of S. brasiliensis in other regions of RJ state. The better efficacy of TRB added to the absence of isolates resistant to ITC support the necessity of pharmacodynamics and pharmacokinetics studies for the optimization of the therapeutic protocols. More information about isolates from dogs and cats correlated with the species from the S. schenckii complex, as well as in vitro antifungal efficacy evaluation provide knowledge about therapeutic alternatives. In this way, the present study also provides relevant information about the endemic status in Rio de Janeiro and important data for the treatment of human and animal sporotrichosis. Fungos dim?rficos pertencentes ao complexo Sporothrix schenckii s?o respons?veis pela esporotricose, importante infec??o f?ngica que apresenta distribui??o mundial. Sua conhecida caracter?stica antropozoon?tica apresenta grande relev?ncia no estado do Rio de Janeiro, onde se verifica aumento significativo no n?mero de pacientes humanos e animais acometidos pela doen?a nas ?ltimas d?cadas, destacando-se em tais casos o papel do felino como agente transmissor. A descri??o de novas esp?cies pertencentes ao g?nero Sporothrix, baseada em caracter?sticas fenot?picas e genot?picas, demonstrou o envolvimento de outros componentes deste g?nero na epidemia instalada no estado. A verifica??o de isolados resistentes a itraconazol, antif?ngico amplamente utilizado na medicina humana e veterin?ria para o tratamento da doen?a, ? fato preocupante e tem poss?vel associa??o a recidivas e falhas terap?uticas. O presente estudo objetiva a identifica??o fenot?pica e genot?pica de 168 exemplares oriundos de pacientes felinos e caninos, obtidos na rotina do Diagn?stico Microbiol?gico Veterin?rio - UFRRJ, com determina??o da Concentra??o Inibit?ria M?nima (CIM) frente ? anfotericina B (AMB), cetoconazol (KTC), itraconazol (ITC), terbinafina (TRB) e voriconazol (VRC). A partir de caracter?sticas morfofisiol?gicas foi poss?vel identificar 159 (94,64%) isolados como S. brasiliensis e 9 (5,36%) como S. luriei. Contudo, metodologias moleculares identificaram 168 (100%) S. brasiliensis, a partir de PCR-RFLP em gene respons?vel pela s?ntese de calmodulina. O teste de sensibilidade, realizado a partir do documento M38-A2 (CLSI) determinou maior efic?cia in vitro para TRB, seguido por ITC, KTC, AMB e VRC, respectivamente. Cepas resistentes a ITC n?o foram detectadas no presente estudo. Tais resultados demonstram que a identifica??o alcan?ada exclusivamente por m?todos fenot?picos n?o ? recomendada para caracteriza??o de componentes do complexo Sporothrix schenckii. Comprova-se ainda a predomin?ncia de S. brasiliensis em outras regi?es do estado do RJ. A maior efic?cia de TRB, somada a aus?ncia de exemplares resistentes a ITC, refor?a a necessidade de estudos farmacodin?micos e farmacocin?ticos para otimiza??o dos protocolos terap?uticos atualmente utilizados. Obten??o de maiores informa??es acerca dos isolados provenientes de amostras provenientes de c?es e gatos correlacionados a esp?cies dentro do complexo S. schenckii, bem como a avalia??o da efic?cia in vitro de antif?ngicos proporcionam conhecimento sobre alternativas terap?uticas. Tais informa??es auxiliam no entendimento do quadro instalado no estado do Rio de Janeiro e fornece dados de grande utilidade para o tratamento humano e veterin?rio
Databáze: OpenAIRE
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