My mom had puj obstruction by born in right kidney and now it is enlarged insize 13.8cm,pelvis is narroeing at the ureteric junction,suggest me plz.

There is a cause?: Narrowing of the PUJ can be caused by scar or some other pathology. This can produce what is called Hydronephrosis which would be proportionate to the degree of obstruction. Your mother should consult a Urologist to check if she needs further tests to find the cause and correct the problem before the obstruction causes any damage to her kidney.