In reply: Kidney stones

In Reply: I thank Dr. Keller for his kind letter.

With respect to expulsive therapy, Dellabella et al¹ randomly assigned 210 patients to receive nifedipine, tamsulosin, or phloroglucinol. All the patients also received a corticosteroid. The most effective therapy was tamsulosin, though this was not a placebo-controlled study. In a separate study, Borghi et al² compared methylprednisolone plus nifedipine and methylprednisolone plus placebo. The nifedipine-methylpednisolone combination seemed to result in more prompt stone passage.

With respect to calcium supplements in calcium kidney stone disease, Curhan et al³ prospectively examined stone risk associated with dietary calcium as well as calcium supplements. This seemed to show that with calcium supplements there was no increased risk, and there may have even been some benefit. In another study by Borghi et al,⁴ normal dietary calcium intake was shown to be associated with lower stone risk than a low calcium intake. Further, the study by Curhan et al³ seemed to indicate the same.