Brief Answer:
No specific dietary restriction is needed

Detailed Answer:
Hello
Thanks for the query

I can understand your concern. No specific dietary restriction is needed for lactating mother who feeds baby suffering from unilateral hydronephrosis.
The most common cause of one sided hydronephrosis is pelviureteral junction obstruction.
The management depends on the severity of hydronephrosis and functional status of the affected kidney.
The functional status can be assessed with the help of DTPA scan.
Pain or crying is uncommon in unilateral hydronephrosis unless there is urinary infection.It is more common in both sided hydronephrosis where posterior urethral valve can cause retention of urine and thus discomfort to the baby. Crying in evening in this age can be due to evening colic.I suggest you to give him some anti colic medication like colicaid or neopeptine drops.
Avoid using spices,salty food containing high sodium.

I would like to know if there is dribbling of urine and if it is there consult your doctor for early evaluation.

I hope this helps.
Please let me know if you have any more queries.
Regards

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Brief Answer:
A repeat USG and DTPA along with MRI will be needed

Detailed Answer:
Hello

Thanks for follow up

Unilateral hydronephrosis with renal pelvis diameter of 17 mm and percentage of function of 37% suggests that it is of moderate to severe grading.
Follow up with DTPA and USG would better guide the management.The most common pathological cause of unilateral hydronephrosis is PUJ obstruction(Functional cause is less common in such grade).The exact cause of PUJ obstruction in neonate is not well known and it is assumed as a intrauterine developmental abnormality.
If there is PUJ obstruction surgery is needed in most of the cases.So imaging (MRI or CT scan)should be done to find out the cause of hydronephrosis.
So I would suggest you to keep him in regular follow up for better management.

Thanks and regards

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