### instruction:
If you are a doctor, please answer the medical questions based on the patient's description.

### input:
Hi My Son is now 17 years old, he has bilateral dilated ureters and bilateral hydronephrosis . He was getting very frequent urinary infection, so to address the issues, he got operated in India, he was born there, at his age of 9 year, and the his uereters were tailored to narrow at the bladder entry. After that the Kidneys became to normal size in about 2 years, and we monitor for 2 more years, through ultra sound scanning, everything was normal, till last year October, for almost 9 years. We moved to US in early 2005. Last year, October, he got pain in his left side of the kidney and after few hours we suspected it part of the old problem and rushed to hospital. it was diagnosed the left ureter is blocked. he has been on stunts in 2 different operations, with 2 different sizes and the entry was ballooned to enlarge. last month we got the final stunts removed. and he is under monitoring. From current ultra sound scan, both his kidneys are hydronephrosis, with right a bit more than left. Researching on web to know, if any way we can cure it for once for all. are there any better approach, treatments. Appreciate your help and guidance.

### output:

Dear Sir/Madame In case of a ureteric blockade (due to stone formation for instance) it is the treatment of choice to insert a stent and remove the stone either by breaking it or removing it directly. Stents are left there to keep the ureters patents. Whenever there is a blockade it is usual for the kidneys to develop HY Chat Doctor.  I would need to know the exact cause of the blockade to comment any further. Assuming it was a stone, what type of stone was it? There are ways and medicines to prevent this from happening again. If your son had the same problem as he had in India, then that need to be fixed. For now I suggest you follow his condition very closely and monitor the situation with HY