Revolutionary Gut Bacteria Therapy Shows Potential for Kidney Stone Prevention

Recent advances in microbiome research reveal that genetically engineered gut bacteria could become a novel treatment for kidney stones. Scientists at Stanford University have developed modified bacteria aimed at reducing oxalate levels, a primary contributor to kidney stone formation. Their study, published in Science, demonstrates promising results from both animal and human trials.

The research focused on Phocaeicola vulgatus, a bacterium naturally present in the human gut. The scientists genetically altered this microbe to enhance its ability to degrade oxalate, a chemical compound linked to kidney stones. To regulate the bacteria's activity, they also incorporated the consumption of porphyran, a seaweed-derived nutrient that serves as a control mechanism for the bacteria's population.

In animal experiments, rats fed diets high in oxalate showed significant reductions—up to 47%—in urinary oxalate levels after receiving the engineered bacteria. Additionally, rats that underwent a gastric bypass procedure mimicking human enteric hyperoxaluria exhibited a 51% increase in urine oxalate, which was completely counteracted when colonized with the modified bacteria. Importantly, the bacteria could be eliminated by removing porphyran, indicating a controllable and reversible process.

The study also included a phase 1/2a clinical trial involving 39 healthy individuals and patients with enteric hyperoxaluria (EH). Results showed that colonization of the engineered bacteria was dose-dependent and generally reversible upon stopping porphyran intake. Some bacteria mutations were observed, likely due to genetic exchange within the microbiome, but these did not cause adverse effects.

Participants with EH experienced some benefits, including a 27% average reduction in urinary oxalate, though the results were not statistically significant, possibly due to small sample size. The study highlights ongoing challenges like bacterial stability and mutation, but also indicates the potential of microbiome-based therapies for kidney stone prevention.

Overall, researchers are optimistic that with further refinement, engineered gut bacteria could offer a safe, effective, and non-invasive approach to managing conditions related to oxalate accumulation and kidney stones.

Source: [https://medicalxpress.com/news/2025-07-genetically-gut-bacteria-combating-kidney.html]