(Marshall Dermer) wrote in message ...
Max is our beloved 6 year-old Havanese, who weighs about 17.4 lbs
and has a history of calcium oxalate crystals in his urine and who,
about one year ago, had three calcium oxalate uroliths removed
from his bladder.

He has been on a diet formulated by a veterinary nutritionist
for about two months and previously was on the Strombeck pea/rice diet to
prevent calcium oxalate uroliths, and earlier still he was on Hill's
Canine U/D.

Today, I brought Max to our veterinarian, Terry Jacobs, for examination.
Max's overall health status looked fine but Terry was concerned about an
abundant level of struvite crystals in Max's urine. Regarding the urine, no
calcium oxalate crystals were evident, the PH was 8, and there were no red
blood cells evident. Terry is culturing a sample of Max's urine to
see if Max has a urinary tract infection.

This is really too high. Bearing in mind that each pH is not exactly a
simple scale. Something that is the pH of 8 is greatly more alkaline
than a pH of 7.5. It would not be surprising to find struvite crystals
in urine with this pH. Target pH for u/d for example is 7.4, with a
range of 7.1-7.7. While 7.7 seems only a few tenths of a point from
8.0, it is actually quite a big difference. One of the difficulties
with pH test strips is the inability to measure the "tenths" of a
point. The difference between 8.0 and 7.7 is not always easily
detectable. (Marshall, I'm not sure about the strips you are using as
I have never looked at them, so I'm referring to commonly availble pH
strips.)


Terry palpated Max's abdomen but could not find evidence of stones.
He mentioned an X-ray but I declined given that Max does not seem
to have problems urinating.

About the only thought Terry had was to reduce the alkalinitiy of Max's
urine by reducing or eliminating potassium citrate supplements.

I would agree.


Managing Max's urine PH has been a interesting exercise. Terry had Max on
500 mgs of potassium citrate BID, but this was way too much. After weeks of
experimenting I came to give Max 35 mgs in the morning and 70 mgs at night.
I divided the dose this way because Max's morning urine tends to be more
acidic than his evening urine. The result of this supplementation was that
Max's morning urine is about PH 7 and his evening urine is PH 8 or PH 8.5.

As I recall, when the stones were detected in Max's urine last year
the urine PH was about 5.6.

I am planning to experiment with altering the PH and bringing in fresh urine
samples to see if we could find some optimal PH that minimized both struvite
and calcium oxalate crystals. (I am assuming that Max does not have
a urinary tract infection. We'll be waiting for the results of
culturing his urine.)

After collecting the "fresh urine", be sure the clinic is ready to
receive it and tests it very quickly. Even a few hours can greatly
alter the results.

Keep us appraised, I find this case really interesting.