Brief Answer:
There is a likely stone in the mid left ureter causing obstacle to passage of urine.

Detailed Answer:
Hi,
Thanks for writing in to us.

The ureter is a tube which connects the kidney to the urinary bladder. The urine generated in the kidney is transported to the urinary bladder along the ureter.

When there is any obstacle to the passage of urine through the ureter then there is dilatation.

In your case I guess there is a stone in the left mid ureter (this is the commonest cause) which is causing an obstacle to the passage of urine. The widening of the ureter proximal to the obstacle is called dilatation.

Your primary might refer you to the urologist for treatment of your condition.

Hope your query is answered.
Please do write back if you have any doubts.

Regards,

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