“…In stone formers from the Middle East, UA stones represent the second most encountered stone type after CaOx stones [44,45], whereas in large series of stone formers from developed countries, UA stones represent the third most encountered stone type, following in frequency CaOx and calcium phosphate stones [46][47][48]. However, several single-center longitudinal series have reported a progressive increase in the proportion of UA stones over the past 3-4 decades [49,50], and a recent large U.S. multistate series of nearly 100 000 stones analyzed between 2016-2019 reported UA stones to be the second most encountered stone type after CaOx stones [51 ,53,54], and are significantly more common among male (vs. female), older (vs. younger), obese (vs. nonobese), and diabetic (vs. nondiabetic) stone formers [51…”