Alleviation of refractory IgA nephropathy by intensive fecal microbiota transplantation: the first case reports

BACKGROUND: Gut dysbiosis may be implicated in the pathogenesis of IgA nephropathy (IgAN) through immune and/or metabolite pathways. Fecal microbiota transplantation (FMT) could reestablish the micro-ecological balance in IgAN, although this has never been attempted before. We explored whether FMT could be efficacious in treating IgAN in two patients with refractory IgAN. CASE PRESENTATION: Two Chinese female patients with IgAN failed to achieve clinical remission after receiving several rounds of immunosuppressive therapy and suffered from unbearable adverse effects due to immunosuppressants. Both patients received intensive fresh FMT conducted through transendoscopic enteral tubing (TET) regularly for 6–7 months, and were followed up for a further 6 months. Partial clinical remission was achieved in both patients, evidenced by a decrease in the 24-h urinary protein (24-hUP) to less than half of baseline during FMT treatment or follow-up, along with increased serum albumin (sAlb) and stable kidney function. The gut microbiota of both patients was distorted with lower biodiversity and altered composition, which was reversed following FMT. Phylum Proteobacteria decreased while genus Prevotella increased during and after FMT. The intensive fresh FMT was well-tolerated, and no severe adverse events occurred. CONCLUSIONS: Preliminary evidence of the safety and efficacy of FMT for treating refractory IgAN may provide a new direction by which to decipher the pathogenesis of IgAN.