Pre-renal cat

Question
Hi...I'd like to find out some more information on pre-renal cats...I have a 6 year old Birman who is considered pre-renal...last two blood tests have shown his BUN and creatinine to be slightly elevated (just above the high normal).  Should I be supplementing him with sub-q fluids?  Would it be advisable to start him on a prophylactic pre-renal diet?  If so, what does that consist of?

Thank you for your help,
Allison

Answer
Hello Allison,

Was a urine specimen checked as well?  If not, it should be to check urine specific gravity, which is a function of how well the kidneys are concentrating urine, and checking the urine will rule out any underlying infection.  Pre-renal can also be from dehydration alone.  Was his albumin eleveated?  If so, he is dehydrated.  The urine specific gravity for cats in full-blown kidney failure is 1.018-1.012.  A urine specific gravity of >1.030 is a good sign that the kidneys are working as well as a visible golden yellow colored urine.  Kidney failure cats will have very pale urine because the kidneys can not conserve and concentrate any longer.

At this point I would recommend starting him on Hills Prescription k/d diet and then recheck kidney values in a few months to see if the diet alone is working.  If the values are remaining the same or elevating, then you could start him on some SQ Fluids.  In addition, the more canned food he will eat the better to keep him well hydrated.  I would also recommend that you add a few extra water dishes around the house that are NOT next to food dishes to encourage him to drink more water.

Good luck,
Dr. Fry