Some ultrasound doctors will explain “kidney crystals” as follows: “kidney crystals” is a diagnosis that can be used when it is difficult to clearly determine whether a kidney stone is present. Why? Because “kidney crystals”, like salt and sugar, can be hidden (dissolved) and present (precipitated) at different concentrations, and the ultrasonographer has a comfortable explanation when reviewing whether “kidney crystals” exist or not. In fact, kidney crystals can be understood as the preformation of kidney stones. An important reason for the formation of kidney stones is the low daily intake of water, resulting in the precipitation of crystals in the urine, which will form stones in the long run. If you can increase the amount of water you drink in time, the increased amount of urine will dilute or dissolve the crystals in the urine, which will be discharged from the body, similar to the principle of salt and sugar crystal precipitation. Of course, for gout patients, abnormal purine biosynthesis and metabolism in the body can lead to excessive production or poor excretion of uric acid, which can raise uric acid in the blood. If uric acid crystals are deposited in joints, cartilage and other parts of the body will cause recurrent inflammation and pain in the corresponding parts of the joints (i.e. gout); if deposited in the kidney, it will lead to kidney stones. Whether it is due to the formation of crystals in the urine concentration in the kidney or the deposition of urate crystals in gout patients, they are manifested under ultrasound as isolated or multiple intense spots in the kidney (as shown below), with a size of several 1-2mm, which are mostly blurred or difficult to detect on x-ray films. Of course, for some small calcified foci in the kidney, the size is too small to be diagnosed differently from crystals or small stones, and some ultrasonographers will consider “kidney crystals” as the final diagnosis again and again to mitigate the possible risks. In one case, a patient was diagnosed with calcified foci on one side of the kidney on ultrasound, and the next day the patient was seen in the emergency room for ureteral calculi (caused by stones falling into the ureter from within the kidney). Therefore, once you have been diagnosed with “kidney crystals” by ultrasound, you need to take it seriously, otherwise you may be troubled by kidney stones at any time and regret it. When you have kidney crystals, do not be discouraged, should pay attention to the usual more water, to develop a habit of drinking water; eat less spinach and other foods containing high oxalic acid; gout patients, try to eat less animal offal and other foods containing high uric acid, and timely treatment.