Hold a little urine waist distension, possible causes: 1, acute pyelonephritis or renal abscess, can appear when holding urine waist distension and pain, and accompanied by chills, high fever, urinary frequency, urinary urgency and other symptoms, is a typical manifestation of upper urinary tract infection, need to carry out routine urine laboratory tests, such as urine can be seen in the leukocyte tubular pattern can be diagnosed. At the same time need to carry out urine culture examination, clear pathogenic bacteria, positive early anti-infection treatment. 2, ureter, bladder, kidney reflux disease, urine in the bladder through the ureter retrograde into the kidneys, the emergence of high pressure in the renal pelvis, there will be a lumbar distension and pain, often in ureteral tuberculosis or ureteral stenting after the operation of the patient. Because holding in urine increases intravesical pressure, urine can enter the kidneys through the rigid ureteral orifice or through the ureteral stent tubes, resulting in low back pain, which requires an indwelling catheter to relieve intravesical pressure or anti-infective treatment to reduce symptoms. Removal of the ureteral stent tube should be considered in patients who have had stent tube placement and experience frequent back pain from urine holding.