What is the main cause of oliguria due to ureteral stones?

The main causes of oliguria due to ureteral stones include obstruction by the stone, kidney function impairment, and ureteral spasm, which collectively prevent normal urine production and excretion. 1. Stone obstruction: Ureteral stones may block the flow of urine within the ureter, preventing urine produced by the kidneys from reaching the bladder normally, thereby reducing urine output and leading to oliguria. 2. Kidney function impairment: Obstruction and inflammatory responses caused by the stone may damage renal parenchyma, impairing glomerular filtration function and reducing urine production. 3. Ureteral spasm: The stone can irritate the ureteral mucosa, causing ureteral spasm that significantly narrows the ureter, thus hindering normal urine passage. If related symptoms occur, prompt medical attention and professional treatment are recommended.