Resumo Enterocytozoon bieneusi é um patógeno intestinal oportunista que infecta humanos e uma variedade de animais em todo o mundo. O objetivo no presente estudo foi investigar a ocorrência de E. bieneusi em uma população de gatos domésticos em Campo Grande, Mato Grosso do Sul, Brasil. Sessenta amostras fecais de gatos diarréicos foram submetidas a reação em cadeia da polimerase (PCR) e os produtos de amplificação foram sequenciados para identificação molecular. E. bieneusi foi detectado em duas amostras (3,3%), ambos identificados como genótipo D. Esse genótipo tem sido relatado em animais e humanos e é considerado um genótipo zoonótico. Nossos resultados representam a primeira descrição de E. bieneusi em gatos domésticos no Brasil, reforçando a importância desse agente como fonte de infecção para animais e humanos.

Abstract Enterocytozoon bieneusi is an opportunistic intestinal pathogen that infects humans and a wide variety of animals worldwide. Our aim in this study was to investigate the occurrence of E. bieneusi in a domestic cat population in Campo Grande, Mato Grosso do Sul, Brazil. Sixty fecal samples from diarrheic cats were subjected to polymerase chain reaction (PCR) and the amplicons were sequenced for identification. E. bieneusi was detected in two samples (3.3%), both identified as genotype D. This genotype has already been reported in animals and humans and is considered a zoonotic genotype. Our findings represent the first report of E. bieneusi in domestic cats in Brazil, reinforcing the importance of identifying this agent as a source of infection in animals and humans.

BACKGROUND Enterocytozoon bieneusi are the most common microsporidia associated with different clinical manifestations such as diarrhoea, respiratory tract inflammation and acalculous cholecystitis, especially in immunocompromised patients. Infection usually occurs by ingestion of food and water contaminated with spores, but can also result from direct contact with spores through broken skin, eye lesions, and sexual transmission, depending on the microsporidian species. Although there are reports of E. bieneusi found in humans and animals in Brazil, there are no published studies of environmental samples examined by molecular methods. OBJECTIVES The purpose of this study was to verify the presence of E. bieneusi in raw sewage and treated effluent from a combined system by molecular methods. METHODS Raw sewage and treated effluent samples collected from a combined system were analysed for the presence of E. bieneusi using the internal transcriber spacer (ITS) region of E. bieneusi by nested polymerase chain reaction. FINDINGS The analysis revealed E. bieneusi presence and a novel genotype (EbRB) in one raw sewage sample and one treated effluent. MAIN CONCLUSIONS The presence of E. bieneusi in final effluent indicates that the combined system may not remove microsporidian spores. This study is the first report of E. bieneusi in environmental samples in Brazil.

O impacto da infecção por Cystoisospora felis na eficiência nutricional de gerbis foi estudado. As variáveis ganho de peso e consumo de ração foram mensuradas durante quatro semanas em 28 gerbis de laboratório, dos quais 14 foram inoculados com 3,5 × 10(5) oocistos esporulados de C. felis e os 14 restantes serviram como controle. Os animais de ambos os grupos foram pesados, mortos, eviscerados e tiveram suas carcaças e tecidos pesados e comparados. Uma ferramenta moderna desenvolvida para mensurar o desempenho nutricional de animais de produção foi aplicada. Os resultados mostraram eficiência nutricional comprometida dos animais infectados na primeira semana após a infecção. As consequências destes resultados são discutidas aqui, incluindo o possível impacto de infecção no desempenho de animais de produção.

The impact of Cystoisospora felis infection on the nutritional efficiency of gerbils was studied. The variables weight gain and feed intake were measured during four weeks in 28 laboratory gerbils, of which 14 were inoculated with 3.5 × 10(5) sporulated oocysts of C. felis and the remaining 14 were controls. The animals from both groups were weighted, killed, eviscerated and had their carcasses and tissues weighted and compared. A modern tool designed for measuring nutritional performance of farm animals was applied. The results showed compromised nutritional efficiency of the infected animals within the first week after infection. The consequences of these results are discussed here, including the potential impact of infection on farm animals performance.