Bloodwork- what does it mean?

I thought I would post the results of the blood tests that just came back for my 18 yr old female cat Pappo. She started limping about 5 months ago and it has gotten worse from there. You can read more about that here

Anyway, I was hoping that someone could shed some light on the subject. Typing the entire sheet would take forever, so I'll just mention the ones that came in high or low, or ones that might be important:


Sodium: 166 (HIGH) **Reference Range 145-158**
Na/K Ratio: 31 (LOW) **Reference Range 32-41**
Osmolality, Calculated: 350 (HIGH) **Reference Range 299-330**
BUN:36 (high normal) **Reference Range 14-36**
Potassium: 5.4 (high normal) **Reference Range 3.4-5.6**
Magnessium: 2.3 (high normal) **Ref. Range 1.5-2.5**

Phosphorus: 5.6 **Ref. Range: 2.4-8.2**
Creatinine: 1.3 **Ref. Ratio 0.6-2.4**
BUN/Creatine Ratio: 28 **Ref. Ratio 4-33**

I cant say for a cat since I would read it like human ... NA/K is sodium to potassium ratio.. if that is low , stuff isnt coming in and out of cell like it should..Omolality I think is how fast things are moving thru something . Your vet should have throughly reviewed each item... if they didnt call back and get it explained..

I could tell you what the values mean for humans and I assume many are similar for cats but I am not certain - how certain electrolytes come back can show whether the body is getting everything it needs, whether everything is normal.

Sodium - essential in transport of substances across cell membranes . In humans, high sodium can lead to high BP.

Na/K - Na = sodium and K = potassium (rememnber your periodic table of the elements?) - To behave normally, Cells need to have normal diffusion and osmosis of Na and K. An abnormal level means they are not getting what they need for their to be good intracellular health.

Osmolality - tests that determines the total number of particles present in blood, urine, or other fluids. Osmolality increases with dehydration and decreases with overhydration. There are three types of osmolality tests: urine, plasma, and stool. Urine osmolality is an important test for renal concentrating ability of the kidney (does your kitty have renal - kidney probs?)

BUN = blood, urea, nitrogen - tests the amt of nitrogeneous material in the blood as urea. It's a key measurement/ indicator of kidney function.

Potassium - (K) - element essential to nervous system, plays an important role in proteinm synthesis. A high level could indicate renal probs but it has to be dangerously high to indicate severe probs. This one is just high normal. Low K is actually worse since it can lead to cardiac arrest. (This actually happened to me once when I was ill and could not keep food down, my K level became so low (my own dr. said it "was not compatible with life") and I went into heart failure - fortunately at a hospital!

Creatinine - levels also indicate kidney filtration rate, how well they are working.

Your vet can tell you what they all mean together - I could look at each one and tell yuo what they mean but it would be pointless without knowing the overall situation. It does sound as tho there are renal problems of some kind though!

Good luck with your kitty's health!!

For an 18 year old cat those kidney parameters look great to me!!!
The low sodium/potassium ratio could be indicative of addisons disease although this is very rare in cats and usually occurs in young dogs. There is a first time for everything though!
I would ask your vet about those values in particular as low potassium can cause general weakness and lethargy which I think you said your cat was having?
If she was in early renal failure (which wouldn't surprise me at 18 years old ) then that might explain the low potassium as CRF cats often need potassium supplementation.
Did your vet run a T4? That blood test will check her thyroid gland and look for hyperthyroidism. Another very common (and treatable) disease in older cats.
I also did not see a blood glucose on the test results. Diabetes would also be on MY list if I were a vet!

Sorry I just looked over the results again and realised that the potassium is not low, the sodium is just very high. Was your cat dehydrated when the blood was taken?

Originally Posted by Dr. Doolittle

Sorry I just looked over the results again and realised that the potassium is not low, the sodium is just very high. Was your cat dehydrated when the blood was taken?

Click to expand...

I don't think she was dehydrated.

http://www.felinecrf.org/diagnosis.htm#BCP
Thought this site might help you get to grips with blood tests and their results.