Therapeutic effects of probiotics and herbal medications on oxalate nephrolithiasis: a mini systematic review

Background and Objectives: The majority of all kidney stone cases are oxalate urolithiasis with a high risk of recurrence. Beside its widespread occurrence, kidney stones are characterized by severe complications and high treatment costs. Pro- biotics and herbal medications could be forthcoming therapeutic interventions in the management of oxalate kidney stones. Materials and Methods: The PubMed/MEDLINE database was searched for keywords "Oxalobacter formigenes" AND "Oxalate" OR "oxalate degradation" AND "Lactobacillus" OR "Bifidobacterium" OR "recombinant Lactobacillus" OR "Bacillus subtilis", and "urolithiasis" AND "herbal extract". The search returned 253 results, 38 of which were included in the review. Results: Most of the oxalate-degrading probiotics belong to the Oxalobacter formigenes, Lactobacillus, Bifidobacterium, and Bacillus genus with a minimum dosage of 107 CFU in the form of capsules, sachets, and lyophilized powder. Oxalate concentration in media was 5-50mM with an incubation time ranging from 24h to 14 days. The majority of the studies suggested that probiotic supplementation might be useful for reducing urinary excretion of oxalate and urea and alleviation of stone formation. Different herbal extracts were used on murine models of nephrolithiasis (induced by 0.5-3% ethylene glycol) with reduction of renal inflammation and urinary parameters, and calcium oxalate crystals. Conclusion: Several strains of probiotics and herbal extracts confer protective effects against kidney stone/nephrolithiasis, indicating their promising nature for being considered as elements of preventive / adjuvant therapeutic strategies.