Our purpose in this paper is to report some observations which have been made at the Stone Clinic of the Massachusetts General Hospital and in the Research Laboratory since a previous brief report1 in 1937. This paper is not meant to be a well balanced discussion of all the nonsurgical aspects of the kidney stone problem.
The approach to the entire subject has remained fundamentally the same. It is based on the following major premise and its corollary:
A patient with urine of such composition that some crystalloid precipitates out of it is predisposed to the formation of a stone composed largely of the precipitated crystalloid (compare cystine stone in cystinuria, uric acid stone in gout and calcium phosphate or calcium oxalate stone in hyperparathyroidism).
In a case in which there is a tendency for stones composed predominantly of a certain crystalloid to form, treatment should be