Whether a little blockage of urinary stones is serious or not depends on the complications caused by the blockage of the stones, and the common ones are hydronephrosis, difficulty in urination, pain and so on. 1. hydronephrosis: when urinary stones lead to abnormalities in the urinary system, it may cause the urine can not be normally discharged from the body, and it is easy to have hydronephrosis in the kidneys, which can damage the kidneys and lead to the decline of renal function. 2. Difficulty in urination: mainly due to the blockage of ureter and urethra by urinary stones, it may cause difficulty in urination and other situations. 3. Pain: As urinary stones may cause obstruction of ureter, which leads to pain in patients. Patients in daily life should follow the doctor’s instructions to use drugs, light diet, drink more water, to avoid infection, and when there are symptoms of discomfort, consult a doctor in time.