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[|Human|] hi, my ultrasound result says: mild fullness of the left pelvocalyceal structures, consider obstruction from distal ureteral lithiasis vs atony from infection or recent passage of stone non-obstructing nephrolithiasis, right sediments/crystals, left kidney
[|AI|]  Hi, Thanks for writing in. The ultrasound report means that the collecting system of the kidney on left side is swelled up mildly. This can happen due to two main causes.1. There is a stone in the lower end of left ureter (tube connecting kidney to bladder). When this happens there is obstruction to flow of urine and the kidney swells up. There is severe pain in lower abdomen.2. Another possibility is due to infection in the ureter or a recently stone which was initially stuck in the proximal ureter and has subsequently been washed out. The stone in this case can scratch the ureter and cause inflammation leading to swelling of the kidney.