Studies of crystalluria in recurrent calcium lithiasis.

The authors have studied the distribution and total volumes of large and small crystals in the urine of healthy individuals and of those who form stones. Studies carried out on randomly obtained specimens were as reliable in identifying differences as were fasting specimens. Stone forming individuals had a greater number of large crystals and a greater total volume of crystals in the urine than had healthy persons. The urine of stone forming patients who had received treatment showed no difference in crystal volume from that of a similar group who had not been treated, and the same was true of a group of stone forming patients studied before and 6 months after the start of treatment.