Crystalluria is the presence of various crystalline inclusions in the urine. It can occur both in healthy people and be a sign of a serious illness. Diagnostic value is the type of crystals, their number, as well as repeated detection during repeated studies. Some crystals can change the color of urine. Prolonged crystalluria is considered one of the main risk factors for the development of urolithiasis. Crystalluria is detected by microscopic examination of the urinary sediment in a general urinalysis. Correction is carried out as part of the treatment of the underlying disease.