Brief Answer:
Please check her kidney functions if it is really reduced.

Detailed Answer:

Hi,

Decreased urinary output may not have any relation to the ultrasound done , However with her significant previous medical history this should not be ignored. This may be a sign of impaired function of the kidneys.

I would advise she should go to her doctor to check her kidney function test. The ultrasound report may also be helpful .
Also it is important that she keep a good record of her urine .She should pass urine in a jar to see that how much urine she passes in fixed time. This would be very helpful as this is a good indirect measure of kidney functions and would also confirm if she really has decreased urine.

Though this may not be feasible and may not be very necessary if she can see her doctor earlier to check her kidney function.
The doctor would see for other reason of her decreased urine. (of really decreased as measured).

This would be great if you could share the ultrasound report (if available) with us that would give us a good idea.

Hope I have answered your question. I will be glad to answer any further question about this. Please don't hesitate to ask anything you need to know.

Regards
Dr Rahman

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