To understand what causes urolithiasis, first now understand how the body’s urine output is controlled. There is a hormone that controls the amount of urine produced by the human body called arginine pressin, also known as antidiuretic hormone. Due to this antidiuretic hormone, it encourages the kidneys to concentrate the urine produced by the human body, so the human body does not produce too much urine every day. However, when the antidiuretic hormone decreases due to certain reasons, the concentration of urine becomes impaired, which can cause the urine to become dilute and the amount of urine to increase greatly, forming uremia. Another reason is that the kidneys are less sensitive to antidiuretic hormone, that is, the antidiuretic hormone does not work on growth, which can also result in thinning of urine and unrestricted increase in urine volume, leading to uremic syndrome.