Feline Cat

Question
Hi,
I took my cat in for a Senior Exam, and the Vet detected a mass in his abdomen when she examined him.  She did an ultrasound with a small piece of equipment, not the state of art one.  She showed me the slide where she she inserted a needle trying to get specimen of mass.  She said she had to give my cat antibiotics and sent me home with antibiotics.  Is it possible her needle caused an infection in my cat, as how he won't eat.  He does have kidney disease according to labs, and he is havimg an ultrasound next week to look at the mass near bowels.

Answer
The needle aspirate will rarely cause an infection, but since she found something she might have decided to see if the antibiotics might help. They also help with the kidneys sometimes.
Having a needle into your stomach might cause you to lose your appetite for a few days and you didn't tell me how long ago this was.
If he isn't eating a thing by Sunday night you need to call the vet. You might want to try some wet food for him for a few days to see if that stimulates his appetite.

I am sorry to hear about the mass too. That is never good news.
I hope he starts eating again.