Inclusion Criteria:  renal ou ureteral stone confirmed by an abdominal and pelvic computed tomography treatment with rigid or flexible ureteroscopy laser lithotripsy during the procedure bacteriological examination of urine (sterile, bacterial colonization or treated by antibiotics)  Exclusion Criteria:  non-use of laser for stone lithotripsy pregnant women under 18 years old refusal to give informed consent urinary malformation