I currently have a Siamese Male Cat at an Animal Hospital.  

He went into the ER Sunday in VA and they ran blood work during the afternoon.
His BUN was 129 and CREAT was 5.9.  He had IV Fluids and Antibiotics given to
him.  His temp was 91.1 and weight was 6.1

Monday I took him to a regular vet and they redid the blood work at 6pm. His
BUN was 101, CREAT 5.6 and SG was 1.008.  He had IV Fluids and Antibiotics
given to him.  His temp was 96.1.

Monday night we retook him to the ER.  The regular vet does not keep animals
overnight.  They did a Sodium and Potassium test, he was normal.  

We decided to take him to the old vet in PA to have her look over and retest.
They were was his primary vet for over 4 years.  She has had him since Tue
about noon.  She redid the test Wed about 2pm.  His BUN was 115 and CREAT was
5.8; His temp was 102.1.  He was given IV Fluids and Antibiotics.  When I
transported him, it was a fie hour drive.

Shadow is eating, drinking and urinating.  He is active and aware now that he
is rehydrated.  He does have an infection/abscessed tooth in his left side of
the mouth.  She did an X-Ray to reduce the thought of cancer.  The infection
came up over night.  It was not there Saturday, Sunday morning it was there.

She also did a Ultrasound of the kidneys and stated that they do not look
very good.  They are small and the left side is smaller then the other.

Shadow was retested on Friday about 11am.  His BUN was 63 and CREAT was 5.6,
temp 102.6.  He also now weights 7.15.

Shadow had a UTI approximately 6 years ago, there was no crystals and he was
given medication and became fine.  Because of the UTI, we give Shadow the
prescribed C/D diet food (low magnesium) and we have not had an issue since.

Shadow was born 4/1999.
Shadow was tested for FIV and Leuk; he is negative.
He is a purebred and fixed.
We also have another cat from that same litter and Lynk is doing fine.

Shadow did have an issue with biting his tail.  He was given a 1/4 tablet of
Torbutal (5mg) a day and he was fine.  It acted up when it rained or was very
cold out.  He has not had this medicine since Saturday and has not attacked
his tail.  Believed to be a possible arthritis...

We are concerned and wanted to know what the best course of action is.  We
have read about kidney transplants, dialysis, and just Sub-Q fluids with a
special diet.  What are levels that a cat can maintain a happy life?