Table 2.
Overview of human intervention studies investigating the effects of the administration of oxalate-degrading bacteria on lithogenic risk.
| AUTHOR, YEAR [REF] | PROBIOTIC | DESIGN, PARTICIPANTS AND FOLLOW-UP DURATION | KEY FINDINGS |
|---|---|---|---|
| Campieri C, et al. 2001 [36] | Lactobacilli (L. acidophilus, L. plantarum, L. brevis) + Bifidobacterium infantis | Prospective single-arm intervention, 6 calcium stone formers, 4-week of follow-up | All participants experienced redution of urinary oxalate excretion (average 40%) |
| Duncan SH, et al. 2002 [37] | Oxalobacter formigenes strain HC1 isolated from human feces | Prospective single-arm intervention, 2 healthy volunteers, 6-h follow-up | Decrease of urinary oxalate excretion after a dietary oxalate load following the probiotic administration. |
| Lieske JC, et al. 2005 [38] | Oxadrop® (L. acidophilus, L. brevis, S. thermophilus, B. infantis) | Prospective single-arm intervention, 10 stone formers with intestinal malabsorption, 1-month follow-up | Decrease of urinary oxalate excretion shown in 7 participants over 10 (average effect size: −19%). |
| Goldfarb DS, et al. 2007 [39] | Oxadrop® (L. acidophilus, L. brevis, S. thermophilus, B. infantis) | RCT, 20 calcium oxalate stone formers with hyperoxaluria, 4-week follow-up | No significant variation of urinary oxalate excretion after treatment in both intervention and control arm. |
| Okombo J, et al. 2010 [40] | VSL#3 (L. acidophilus, L. gasseri, B. lactis) | Prospective single-arm intervention, 11 stone-free volunteers, 4-week follow-up | Reduction of fractional oxalate absorption after a dietary oxalate load (from 31% to 12%). |
| Hoppe B, et al. 2011 [41] | Oxabact® (Oxalobacter formigenes) | RCT, 42 adolescents with primary hyperoxaluria, 24-week follow-up | Reduction of urinary oxalate excretion in both intervention and control arm (average effect size 20% in both groups) |
| Al-Wahsh I, et al. 2012 [42] | VSL#3 (L. acidophilus, L. gasseri, B. lactis) | Prospective single-arm intervention, 11 healthy stone-free volunteers, 24-h follow-up | Reduction of urinary oxalate excretion after a standardized dietary oxalate load |
| Siener R, et al. 2013 [43] | Oxadrop® (L. acidophilus, L. brevis, S. thermophilus, B. infantis) | Randomized cross-over trial, 20 stone-free healthy volunteers under high-oxalate diet, 5 week follow-up | No significant variation of oxaluria detected. |
RCT = Randomized Controlled Trial.