Question about urinalysis numbers

Hi,

Monday night while I was cleaning the litterbox, Thufir jumped in to pee. He seemed to be straining and his urine was only dribbling out, so I took him in to the vet yesterday to have him checked out. He blocked up completely with struvite crystals ~3 years ago, so I was afraid it was a recurrence of the crystals. The vet pulled his urine with a needle and tested it. In a weird way, I was somewhat happy when she told me that it was a bacterial infection because that means his crystals are under control. She said no crystals were visible in his urine at all. She prescribed an antibiotic and I'll take him back for a recheck in 2 weeks.

Thufir is on a prescription c/d diet, but he only eats it (canned) in the morning and in the evening he eats a standard high-quality canned food (Wellness/Chicken Soup) with my other cats. The numbers from his urinalysis were:

pH: 6.0
Specific Gravity: 1.016

The pH is quite low, so clearly the c/d is doing its job of keeping the urine acidic, but I'm wondering if, on the basis of that number, it would be reasonable to suggest we try to wean him off the c/d completely.

The specific gravity also seems pretty low. I asked my vet about it and she said it was a bit lower than normal. She indicated that the wet food (I add water to it as well) could be causing it, or, on the other hand, it could be a sign of kidney failure. If the SG is still low when I take him in for a re-check in 2 weeks, I'll ask them to run a blood panel to check his kidneys. In the meantime, can anyone tell me what are considered 'normal' values (low, high,median) for the pH and specific gravity? I'm just curious where Thufir's values fall in those ranges.

Here are some approximate normal ranges for Urine Specific Gravity (USG), and the links to the information:

The normal range for specific gravity is between 1.015 and 1.060 but only concentrations higher than about 1.030 can be considered solid evidence of normal kidney function.
http://felinecrf.com/tests0.htm

The normal range is 1.008 to 1.060 but a cat with a USG below 1.040 is generally considered to have a problem of some kind; in CRF cats it will probably be between 1.008 and 1.012.
http://www.felinecrf.org/diagnosis.htm#urinalysis

Each lab will have a normal range that is specific to that diagnostic machine. Most labs will list the reading, and also list the normal range in parenthesis.


I've never had Cleo's USG tested, because she gets subQ fluids two to three times a week. The fluids would affect the USG reading, so I rely on her bloodwork, specifically, BUN, Creatinine and serum Phosphorus.

Lola had a cystocentesis last week to diagnose her UTI. She did have crystals in her urine, but Dr. Sue said that they were most likely due to the infection.

Thanks,

That's the type of info I was looking for. I have a really large book on cat health, but since it's geared towards cat owners rather than vets, it doesn't give info for various tests except to tell what they are.

The specific gravity information seems to about what my vet told me: 1.016 isn't necessarily low, but it's low enough that the function of the kidneys can't be guaranteed. He's nearly 10, so I'll probably ask them to do a blood panel just to be sure.

The second link also shows that the range of normal pH values is 6.0-6.5 so if that's true, then Thufir's value of 6.0 lies on the low end of the normal range. If it's still running at ~6.0 when I take him back in for a recheck, I'll definitely discuss the possibility of reducing or eliminating the c/d with my vet. I think it's pretty poor quality food and having to feed him separately is a hassle.

Glad I could help! I hope Thufir responds well to the antibiotics, and gets well quickly! Lola had her first UTI about a year and a half ago. We had to try three different antibiotics before we found one that cleared it up. Good luck to you both!