Bladder stones are rare in women and children, but are common in men due to the greater incidence of lower urinary tract obstruction, e.g., prostate enlargement. Ten percent of males will experience kidney stones during their lifetime, which is almost three times the incidence in females. Caucasians are affected more commonly than other racial groups. Urinary calculi have been around for centuries. Stones were found in an Egyptian skeleton estimated to be over 7,000 years old.
Kidney stones are more common in developed nations and do have regional variation in occurrence.
Although kidney stones have not been eradicated, we have learned a great deal about them. Heredity, environment, age, sex, urinary infection, diet, and metabolic diseases are probably involved in stone formation. Stone disease tends to run in families through a mechanism of partial penetrance due to a genetic defect. The typical stone patient is a Caucasian male between 20 and 60. In contrast, calculi are relatively common in children in Asia.