Management of infection stones: the Stanford experience.

In summary, 46 renal lithotomies were performed in 40 patients for struvite infection stones. All patients had documented urinary tract infections at the time of surgery; all stones were cultured, demonstrated to contain bacteria and proved crystallographically to be composed primarily of struvite with smaller amounts of apatite. The recurrence rate in a mean followup period of 7 years was 2.5% (one patient). The negligible recurrence rate emphasizes that struvite stones are caused by urea-splitting bacteria, rather than metabolic disorders, and that a comprehensive approach that emphasizes biochemical, bacteriologic, and roentgenographic techniques is more important than the type of surgical procedure used to remove the stones. We believe that our routine of leaving a small polyethylene nephrostomy tube in every patient, combined with postoperative plain-film tomograms regardless of the results of intraoperative radiography, and the liberal use of hemiacidrin irrigation to dissolve any residual struvite particles with their entrapped bacteria, accounts for the virtual absence of stone recurrences in our series.