Low prevalence of Blastocystis sp. in active ulcerative colitis patients

Abstract

Ulcerative colitis (UC) is thought to originate from a disbalance in the interplay between the gut microbiota and the innate and adaptive immune system. Apart from the bacterial microbiota, there might be other organisms, such as parasites or viruses, that could play a role in the aetiology of UC. The primary objective of this study was to compare the prevalence of Blastocystis sp. in a cohort of patients with active UC and compare that to the prevalence in healthy controls. We studied patients with active UC confirmed by endoscopy included in a randomised prospective trial on the faecal transplantation for UC. A cohort of healthy subjects who served as donors in randomised trials on faecal transplantation were controls. Healthy subjects did not have gastrointestinal symptoms and were extensively screened for infectious diseases by a screenings questionnaire, extensive serologic assessment for viruses and stool analysis. Potential parasitic infections such as Blastocystis were diagnosed with the triple faeces test (TFT). The prevalence of Blastocystis sp. were compared between groups by Chi-square testing. A total of 168 subjects were included, of whom 45 had active UC [median age 39.0 years, interquartile range (IQR) 32.5–49.0, 49 % male] and 123 were healthy subjects (median age 27 years, IQR 22.0–37.0, 54 % male). Blastocystis sp. was present in the faeces of 40/123 (32.5 %) healthy subjects and 6/45 (13.3 %) UC patients (p = 0.014). Infection with Blastocystis is significantly less frequent in UC patients as compared to healthy controls.

Recruitment of feces donors among blood donors: Results from an observational cohort study

“…Notably, controversy exists to whether certain protozoa such as Blastocystis species may be more prevalent in healthy individuals and linked to certain beneficial health indices. 22 , 23 For now, however, our data are consistent with the findings of diverse pathogens reported by others 14 , 15 and support the current broad-spectrum screening approach for pathogens.…”

A Study on the Prevalence and Subtype Diversity of the Intestinal Protist Blastocystis sp. in a Gut-Healthy Human Population in the Czech Republic

“…has been considered as a potential pathogen associated with irritable bowel syndrome [IBS] (Poirier et al, 2012 ; Nourrisson et al, 2014 ) and inflammatory bowel diseases [IBD] (Petersen et al, 2013 ). However, it appears to be more common in the gut of healthy individuals compared to those with gut disease, and it is now by many considered a commensal (Petersen et al, 2013 ; Scanlan and Stensvold, 2013 ; Parfrey et al, 2014 ; Krogsgaard et al, 2015 ; Rossen et al, 2015 ; Stensvold and van der Giezen, 2018 ; Mardani Kataki et al, 2019 ; Tito et al, 2019 ). Moreover, Blastocystis sp.…”

Blastocystis Colonization Is Associated with Increased Diversity and Altered Gut Bacterial Communities in Healthy Malian Children

“…Interestingly, Blastocystis is commonly detected in the gut of asymptomatic humans, and it has been shown that colonization is stable over 6-10 years [16,17]. It was shown that Blastocystis was more frequent in healthy subjects compared to subjects with IBD, pointing out a possible protective effect of its colonization [18][19][20]. It is known that the gut microbial communities include protozoa, fungi, bacteria, and viruses, which share the same environment and live in close relationship.…”