Division of Nephrology and Hypertension, Department of Internal Medicine, Mayo Clinic, Rochester, Minnesota 55905, USA.
Kidney Int. 2010 Dec;78(11):1178-85. doi: 10.1038/ki.2010.310. Epub 2010 Aug 25.
We examined the effect of a controlled diet and two probiotic preparations on urinary oxalate excretion, a risk factor for calcium oxalate kidney stone formation, in patients with mild hyperoxaluria. Patients were randomized to a placebo, a probiotic, or a synbiotic preparation. This tested whether these probiotic preparations can increase oxalate metabolism in the intestine and/or decrease oxalate absorption from the gut. Patients were maintained on a controlled diet to remove the confounding variable of differing oxalate intake from food. Urinary oxalate excretion and calcium oxalate supersaturation on the controlled diet were significantly lower compared with baseline on a free-choice diet. Neither study preparation reduced urinary oxalate excretion nor calcium oxalate supersaturation. Fecal lactobacilli colony counts increased on both preparations, whereas enterococcal and yeast colony counts were increased on the synbiotic. Total urine volume and the excretion of oxalate and calcium were all strong independent determinants of urinary calcium oxalate supersaturation. Hence, dietary oxalate restriction reduced urinary oxalate excretion, but the tested probiotics did not influence urinary oxalate levels in patients on a restricted oxalate diet. However, this study suggests that dietary oxalate restriction is useful for kidney stone prevention.
我们研究了控制饮食和两种益生菌制剂对轻度高草酸尿症患者尿草酸盐排泄（草酸钙肾结石形成的危险因素）的影响。患者被随机分配到安慰剂、益生菌或合生元制剂组。这是为了检验这些益生菌制剂是否能增加肠道中的草酸盐代谢，或减少肠道对草酸盐的吸收。患者被维持在控制饮食中，以消除饮食中不同草酸盐摄入的混杂变量。与自由选择饮食时的基线相比，控制饮食时尿草酸盐排泄和钙草酸饱和度明显降低。两种研究制剂均未降低尿草酸盐排泄或钙草酸饱和度。两种制剂均可增加粪便乳杆菌菌落计数，而合生元则可增加肠球菌和酵母菌菌落计数。总尿量以及草酸盐和钙的排泄均是尿钙草酸饱和度的强独立决定因素。因此，饮食中限制草酸盐可减少尿草酸盐排泄，但在限制草酸盐饮食的患者中，所测试的益生菌并未影响尿草酸盐水平。然而，本研究表明，饮食中限制草酸盐对于预防肾结石是有用的。
