Clinically, bilateral hydronephrosis is serious, as it can lead to expansion of the renal pelvis. Long-term bilateral hydronephrosis can compress the renal parenchyma, leading to the development of chronic obstructive nephropathy, and thus cause chronic renal failure. Additionally, because urine cannot be expelled from the body in a timely manner in bilateral hydronephrosis, it is easy to combine with bacterial infections, which can lead to acute pyelonephritis. Patients may experience chills, fever, and severe back pain, as well as hematuria and general fatigue. Therefore, it is essential to identify the cause of bilateral hydronephrosis and treat it based on the nature of the hydronephrosis. Usually, the causes of bilateral hydronephrosis are related to stones, but tumorous diseases, bladder stones, or urethral strictures are also common causes.