Occurrence of Blastocystis spp. in domestic animals in Triângulo Mineiro area of Brazil

Abstract INTRODUCTION: Currently, there are few studies regarding Blastocystis epidemiology. This study aimed to evaluate the occurrence of Blastocystis in animals in Uberaba, Brazil. METHODS: Fecal samples were examined by parasitological methods and screened for Blastocystis by polymerase chain reaction. RESULTS: Blastocystis spp. were observed in pigs, sheep, cattle, and dogs. Blastocystis polymerase chain reaction was positive in 14/22 samples positive by parasitological methods. CONCLUSIONS: The occurrence of Blastocystis in animals is high, with a predominance of subtype 1 in the region. This is the first study conducted in Brazil showing the genetic profile of Blastocystis isolated from animals.

OCCURRENCE OF Blastocystis spp. IN UBERABA, MINAS GERAIS, BRAZIL / Ocorrência de Blastocystis spp. em Uberaba, Minas Gerais, Brasil

Intestinal parasites are a problem for public health all over the world. The infection with Blastocystis, a protozoan of controversial pathogenicity, is one of the most common among them all. In this study, the occurrence of intestinal parasites, with emphasis on Blastocystis, in patients at the Universidade Federal do Triângulo Mineiro was investigated in Uberaba (MG) through microscopy of direct smears and fecal concentrates using Ritchie’s method. Feces of 1,323 patients were examined from April 2011 to May 2012. In 28.7% of them at least one intestinal parasite was identified, and the most frequent organisms were Blastocystis spp. (17.8%) and Giardia intestinalis (7.4%). The occurrence of parasitism was higher in children aged 6 -10 years old, and the infection with Blastocystis spp. was higher above the age of six (p < 0.001). The exclusive presence of G. intestinalis and of Blastocystis spp. was observed in 5.4% and 12.2% of the patients, respectively. Regarding patients with diarrheic feces, 8% revealed unique parasitism of Blastocystis spp. Other intestinal parasites observed in children were Ascaris lumbricoides (0.3%) and Entamoeba histolytica/dispar/moshkovskii (1.4%). The Ritchie’s method was more sensitive (92.8%) when compared to direct microscopy (89.8%), with high agreement between them (97.7%, kappa = 0.92). In conclusion, the occurrence of Blastocystis spp. in Uberaba is high and the presence of diarrheic feces with exclusive presence of the parasite of Blastocystis spp. was observed.

Parasitos intestinais são um problema de saúde pública no mundo e a infecção por Blastocystis, protozoário de patogenicidade controversa, é uma das mais frequentes. Nesse estudo foi investigada a ocorrência de parasitos intestinais em pacientes atendidos na Universidade Federal do Triângulo Mineiro, em Uberaba (MG), com ênfase em Blastocystis, pelos métodos parasitológicos direto e de Ritchie. Foram examinadas fezes de 1.323 pacientes de abril/2011 a maio/2012. Em 28,7% deles foi identificado um parasito intestinal, sendo Blastocystis spp. (17,8%) e Giardia intestinalis (7,4%) os mais frequentes. A ocorrência de parasitismo foi maior em crianças de 6-10 anos e a infecção por Blastocystis spp. foi maior acima de seis anos (p < 0,001). Presença exclusiva de G. intestinalis e de Blastocystis spp. foi observada em 5,4% e 12,2% dos pacientes, respectivamente, sendo que dos pacientes com fezes diarreicas, 8% apresentavam parasitismo exclusivo por Blastocystis spp. Outros parasitos intestinais observados em crianças foram Ascaris lumbricoides (0,3%) e Entamoeba histolytica/dispar/moshkovskii (1,4%). O método de Ritchie foi mais sensível (92,8%) que o direto (89,8%), com alta concordância entre eles (97,7%, kappa = 0,92). Em conclusão, a ocorrência de Blastocystis spp. em Uberaba é elevada e foi observada a presença de fezes diarreicas com parasitismo exclusivo por Blastocystis spp.