Brief Answer:
Thoughts on this

Detailed Answer:
Hello and welcome,

This is difficult to sort out without being able to see your dad and know his medical history. But I'll share my thoughts on this:

A urinary tract infection in an elderly person can cause lethargy.

However, if his abdomen is quite distended, it should be evaluated. Also if the somnolence or change in mental state is new, that should be evaluated too, to make sure the urinary tract infection hasn't progressed, and to check serum chemistry.

Without having seen him, I am hesitant to suggest that you wait to see if the antibiotic that was started yesterday will resolve the somnolence.

I hope, when you took him in to be seen, that they sent a urine sample from him to the lab to have a culture and sensitivity test done. A sensitivity test takes the bacteria that grew in the culture and tests various antibiotics against it, to see if the bacteria is sensitive to them. The lab will provide the doctor with ratings of sensitive, resistant, or intermediate. This is especially important in this age of antibiotic resistance, so that you know that the antibiotic that was given to him will be effective.

So - because of your description of his stomach being very distended, and the new onset of mental status changes, I recommend he be seen again.

You may want to consider having him take a probiotic too, while he is on the antibiotics and for a couple of weeks after, as antibiotics can throw off the gut flora and increase the chances of diarrhea or constipation.

I don't know how long he has been constipated for. If it has been several days, and he is distended, they may want to do a manual disimpaction when he is seen.

I hope this information helps. Please let me know if I can provide further information.

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