Impact of probiotic supplementation on pediatric celiac disease

In children with celiac disease autoimmunity, single-cell protists have a low prevalence, and their colonization remains stable despite probiotic intervention.

A randomized, double-blind placebo-controlled clinical trial [Celiac Disease Prevention with Probiotics (CiPP)] was undertaken to examine the influence of Lactiplantibacillus plantarum HEAL9 and Lacticaseibacillus paracasei 8700:2 on the single-cell parasitome, with a particular emphasis on Blastocystis.

Stool samples were procured from 78 children diagnosed with celiac disease autoimmunity, who participated in a double-blind, randomized, placebo-controlled clinical trial. These children were assigned to either receive a combination of L. plantarum HEAL9 and L. paracasei 8700:2 supplementation (n = 38) or a placebo (n = 40). A total of 227 stool samples gathered at baseline, 3 months, and 6 months during the intervention were retrospectively examined.

The analysis involved quantitative real-time polymerase chain reaction (PCR) for Blastocystis, with subtyping performed using massively parallel amplicon sequencing. Additionally, untargeted 18S rDNA amplicon sequencing and real-time PCR were employed to identify other single-cell parasites. The interaction between parasites and the bacteriome community was delineated by profiling the V3-V4 region of 16S rDNA.

Three distinct single-cell protists were detected, with Dientamoeba fragilis having the highest occurrence (23.1%, 18 out of 78 children), followed by Blastocystis (15.4%, 12 out of 78) and Entamoeba spp. (2.6%, 2 out of 78). The abundance of these protists was unaffected by probiotic intervention and remained consistent over time. The presence of these protists was linked to an elevated diversity of the bacteriome, as estimated by multiple indices.

The bacterial composition was impacted by the presence of the protists; specifically, Blastocystis positivity was inversely correlated with Akkermansia (at both the genus and higher taxonomic levels), Romboutsia, and Faecalibacterium. Similarly, D. fragilis positivity was inversely linked with the Coriobacteriaceae and Enterobacteriaceae families, as well as the genera Granulicatella, Ruminococcus, Lachnoclostridium, Faecalibacterium, and Flavonifractor.

The occurrence of single-cell protists is minimal in celiac disease autoimmunity children. The colonization remained constant despite probiotic intervention and was linked to heightened diversity in the fecal bacteriome, though with an inverse correlation with certain beneficial bacteria.