# Diagnostic, prognostic, and therapeutic potentials of gut microbiome profiling in human schistosomiasis: A comprehensive systematic review

## TL;DR

This review explores how changes in gut bacteria could help diagnose, predict outcomes, and treat schistosomiasis, a parasitic disease.

## Contribution

It systematically identifies gut microbiome patterns associated with schistosomiasis for potential diagnostic and therapeutic use.

## Key findings

- Gut microbiome alterations are linked to schistosomiasis infection and liver pathology.
- Specific bacterial genera like Bacteroides and Prevotella are associated with different Schistosoma species.
- Praziquantel treatment outcomes correlate with gut microbiome composition in S. mansoni-infected children.

## Abstract

Several studies have highlighted alteration in the gut microbiome associated with the onset and progression of diseases. Recognizing the potential of gut microbiota as biomarkers, this systematic review seeks to synthesize current data on the intricate relationship between the host gut microbiome profiles and their usefulness for the development of diagnostic, prognostic and therapeutic approaches to control human schistosomiasis.

A systematic literature review was carried out by searching for relevant studies published until date, that is May 2024, using Medline, Embase, Global Health, Web of Science, and Global Index Medicus databases. The keywords used to select articles were "Gut microbiome", "Gut Microbiota", "Schistosomiasis", "Bilharziasis ", and "Human". Extracted data were analysed qualitatively from the selected articles.

Of the 885 articles retrieved and screened, only 13 (1.47%) met the inclusion criteria and were included in this review. Of the included studies, 6 (46.2%) explored alterations of gut microbiome in schistosome-infected patients, 4 (30.7%) in patients with liver pathologies, and 3 (23.1%) in patients treated with praziquantel. Bacteria from the genera Bacteroides, Faecalibacterium, Blautia and Megasphaera were associated with S. japonicum and S. haematobium infection in school-aged children, whereas infection with S. mansoni rather associated with Klebsiella and Enterobacter. The gut microbiota signature in patient with schistosomiasis-induced liver pathology was reported only for S. japonicum, and the genus Prevotella appeared as a non-invasive biomarker of S. japonicum-associated liver fibrosis. For S. mansoni-infected school-aged children, it further appeared that the treatment outcome following praziquantel administration associated with the abundance in the gut microbiome of bacteria from the classes Fusobacteriales, Rickettsiales and Neisseriales.

The host gut microbiome appears to be a valuable, non-invasive, but still poorly utilized, source of host biomarkers potentially informative for better diagnosing, prognosing and treating schistosomiasis. Further studies are therefore needed to comprehensively define such gut microbial biomarkers of human schistosomiasis and catalyse the informed development of gut microbiome-based tools of schistosomiasis control.

Schistosomiasis orchestrates profound regulation by/of the host immune responses. Given the core role of the gut microbiome in regulating the human immune responses at the systemic level, and the increasingly recognized potential of this host component in biomarking for the identification, monitoring, prevention and treatment of several diseases, we questioned whether the human gut microbiome shows patterns of alterations during schistosomiasis that could robustly inform novel diagnostic, prognostic and therapeutic approaches.

After systematically scrutinizing all available reports in the literature on the gut microbiome dynamics during schistosomiasis in humans so far, available evidences pointed at pathognomonic changes in human gut microbiomes following schistosomiasis infection, progression as pathology develops and treatment. Despite the fact that evidences from most of these studies are not yet definitive i.e. hardly controlled for poly-infections, for diet-driven alterations or for robustness of the observed signatures in large longitudinal studies, some of the gut microbial changes observed so far presented significantly and repeatedly in several individuals and at times in independent studies. This indicates here an exploitable potential for the gut microbiome that warrants more comprehensive and controlled studies to unequivocally identify diagnostic, prognostic and therapeutic gut microbial biomarkers during human schistosomiasis.