Urinary urgency with swelling and pain in the lower back may be caused by pyelonephritis, ureteral stone, pelvic inflammatory disease and other factors. 1. Pyelonephritis: usually caused by bacterial infection, it may cause soreness and pain in the lower back, accompanied by frequent urination, urinary urgency and other symptoms, and in severe cases, it may cause perinephric abscess, necrosis of renal tissue and other serious complications. 2. Ureteral stones: usually secondary to kidney stones, the end of the ureter is narrow, may be stuck in the end of the ureter, can cause lumbar distension and urinary urgency, acute attack will cause severe lumbar abdominal pain, hematuria and other symptoms. 3. Pelvic inflammatory disease: it may be related to poor hygiene or unclean sex, which can cause symptoms such as pain and swelling in the lower back and abdomen, and also accompanied by vaginal bleeding, increased secretion, and in severe cases, it can cause infertility. To summarize, the urgent urination in the lower back, indicating the existence of abnormal conditions, it is recommended to seek medical examination and treatment as soon as possible, do not delay the condition.