Urinary oxalate excretion in female calcium oxalate stone formers with andwithout a history of recurrent urinary tract infections

Therapy with antibiotics in recurrent urinary tract infections may destroy colonies of Oxalobacter formigenes in the intestinal tract. A lack of oxala te degradation caused by the absence of this bacterium is suggested to cont ribute to the hyperabsorption of dietary oxalate and to the increase in uri nary oxalate excretion. The present study was performed to evaluate the eff ect of recurrent urinary tract infections and subsequent changes induced in the urinary excretion profile in female calcium oxalate stone formers. Ser um biochemical profiles, 24-h urinary parameters, and the personal characte ristics of 57 female calcium oxalate stone patients with recurrent urinary tract infections (RUTI) were compared with 78 female calcium oxalate stone patients without a history of urinary tract infection. All subjects were re cruited during the same period. In female patients with RUTI, urinary oxala te excretion was significantly higher (0.374 mmol/day) than in females with out urinary tract infection (0.308 mmol/day) (P<0.05). Moreover, the mean 2 4-h pH value and urinary sodium excretion were significantly higher in wome n with RUTI than in women without a history of urinary tract infection. The significantly higher urinary oxalate excretion in female calcium oxalate s tone formers with recurrent urinary tract infections may be associated with the application of antibiotics an a subsequent temporary or permanent deco lonization of Oxalobacter formigenes.