Identification of Blastocystis subtypes in clinical stool samples from Sao Paulo City, Brazil

Abstract

S U M M A R YBlastocystis sp. is a protozoan commonly found in human and animal stool samples. Several pathogenic and zoonotic aspects of this organism are still unknown. The aim of the present study was to investigate Blastocystis subtypes (STs) in samples from patients of the Hospital das Clínicas of the Faculdade de Medicina at the Universidade de São Paulo (HC-FMUSP), Brazil. Blastocystis sp.-positive stool samples diagnosed at the Section of Parasitology of the Central Laboratory (HC-FMUSP) were used for DNA isolation. Polymerase chain reaction (PCR) was performed using specific primers targeting the small-subunit rRNA gene. Direct DNA sequencing of the PCR products was performed and the DNA sequences were then aligned and compared with other sequences obtained from the GenBank database. Phylogenetic analysis was used to identify STs and determine the phylogenetic relationships between the sequences. Four STs were identified: ST1 (22·5%), ST2 (12·5%), ST3 (60%) and ST6 (5%). In conclusion, ST3 was the most prevalent ST among the human isolates followed by ST1. The present study is one of the few providing STs data from the human population in South America. Determining ST prevalence in human samples may contribute to the monitoring of Blastocystis sp. infection transmission in endemic regions.

Blastocystis genetic diversity among children of low-income daycare center in Southeastern Brazil

“…Among daycare children, Blastocystis was detected in 40.7% of the subjects and infection was also observed in 28.6% and 50% of staff and household members, respectively. These results are consistent with recent surveys in South America, including in Brazil, focused on several cohorts of population such as children (Dib et al, 2015;Rebolla et al, 2016;Ramirez et al, 2017;Sánchez et al, 2017), population in slums (Faria et al, 2017;Gil et al, 2013), indigenous communities (Malheiros et al, 2011;Sánchez et al, 2017), rural communities (Incani et al, 2017;Macchioni et al, 2016;Machicado et al, 2012), fishing village dwellers (David et al, 2015) and individuals visiting hospitals (Casero et al, 2015;Melo et al, 2017). In all these groups, Blastocystis has been often diagnosed with infection rates of < 15% to as high as 50%.…”

“…Notwithstanding the progress made over the last two decades, current interest has focused on the distribution and relevance of Blastocystis subtypes in populations living in low-income areas. Those include Asia (Belleza et al, 2015;Nithyamathi et al, 2016;Pandey et al, 2015;Sanpool et al, 2017), Africa (El Safadi et al, 2014;Poulsen et al, 2016), the Middle East (AbuOdeh et al, 2016;Dogan et al, 2017) and also in Latin America (David et al, 2015;Macchioni et al, 2016;Malheiros et al, 2011;Melo et al, 2017;Ramirez et al, 2014Ramirez et al, , 2016Ramirez et al, , 2017Sánchez et al, 2017;Villegas-Gómez et al, 2016). Recently, the limited data from South America was highlighted (Ramirez et al, 2016(Ramirez et al, , 2017.…”

“…Particularly in Brazil, there have been only three publications of diversity in Blastocystis. One focused on members of an Amazon indigenous community (Malheiros et al, 2011), while the two others conducted among fishing village dwellers (David et al, 2015) and patients attending a university hospital (Melo et al, 2017).…”

Prevalence of Blastocystis sp. infection in several hosts in Brazil: a systematic review and meta-analysis

“…Oliveira-Arbex et al [45] Melo et al [49] David et al [9] Branco et al [58] Miné et al [66] Alarcón et al [68] Kobayashi et al [76] Seguí et al [50] Takizawa et al [64] Borges et al [63] Kulik et al [65] Subtotal (I^2 = 95.61%, p = 0.00) Subtotal (I^2 = 99.28%, p = 0.00)…”

Blastocystosis. La Infeccion Protozoaria Intestinal De Mayor Frecuencia en Humanos en El Mundo

“…que circulan entre una determinada población en un lugar geográfico (STENSVOLD et al, 2012). En Sao Paulo, Brasil se detectaron los subtipos ST1, ST2, ST3 y ST6, los tres primeros subtipos mencionados son los mas frecuentemente reportados en humanos en diversos estudios de blastocystosis en el mundo (MELO et al, 2017).…”