Fecal microbiota transplantation (FMT) is showing promise as an adjunctive therapy for IgA nephropathy (IgAN), according to a recent study published in Nature. The research investigated the safety and efficacy of FMT in conjunction with ACEI/ARB therapy, revealing a potential proteinuria-lowering effect and immunomodulatory action in IgAN patients. The study, involving fifteen participants, explored changes in clinical indicators, gut microbiota composition, and intestinal metabolites before and after FMT.
Impact on Urinary Protein and Immune Cells
The study found that FMT, when used alongside ACEI/ARB therapy, led to a decrease in 24-hour urinary protein quantification in IgAN patients. Specifically, after excluding two participants who experienced acute upper respiratory tract infections, the remaining thirteen showed a significant reduction in urinary protein levels at 1 and 3 months post-FMT. Furthermore, a notable decrease in B cell counts was observed after FMT (p < 0.05), suggesting a potential mechanism through which FMT may modulate the immune response in IgAN.
Gut Microbiota and Metabolite Changes
Metagenomic sequencing revealed alterations in the gut microbiota composition following FMT. The diversity of the intestinal flora increased one month after FMT. Several bacterial species, including Bacteroides uniformis and Bacteroides ovatus, showed significant positive correlations with changes in B cell counts, while Prevotella copri exhibited a negative correlation. Untargeted metabolomic analysis identified significantly different levels of metabolites, such as acylcarnitine18:0 (ACar.18:0), cotinine, N-arachidonoyl-L-serine, phosphatidylcholine (PC.(18:3e/22:6)), serotonin, and fumagillin, before and after FMT (p < 0.05).
Safety Profile
The safety assessment indicated that FMT was well-tolerated, with no severe adverse events reported. Five mild adverse events occurred in two patients, including mild abdominal discomfort in one participant, which resolved after discontinuing medication. Two participants experienced acute upper respiratory tract infections accompanied by elevated urinary protein. While statistically significant differences were observed in serum sodium and serum calcium levels, these changes were not considered clinically significant.
Implications for IgAN Treatment
These findings suggest that FMT could be a valuable adjunctive treatment strategy for IgAN, potentially offering a novel approach to managing proteinuria and modulating the immune system. The observed changes in gut microbiota and metabolites provide insights into the possible mechanisms underlying FMT's therapeutic effects. Further research with larger sample sizes and longer follow-up periods is warranted to confirm these findings and fully elucidate the role of FMT in IgAN management.
