Hypophosphataemia in a 17 year old cat

Re: Hypophosphataemia in a 17 year old cat

Neil Wheadon — Sun, 29 Jan 2012 12:34:16 GMT

As an update I spoke to the owner this morning

He attended the day practices clinic on Saturday morning and he is still ataxic but no worse (if he shakes his head he falls over) however he can jump onto beds and chairs. The vet seeing him has requested a urine sample and will be repeating the blood samples and I'll try to find out what these showed.

In answer to the stressed glucose, he sat easily for a jugular sample, but he had had a car journey and had been seen quickly, so its possibly a stressed glucose but diabetes would certainly be possible. Weither he was ketotic is debatable but the thought is a good one.

This cat was seen at an OOH clinic and everyones input has been very helpful. Thankyou

Re: Hypophosphataemia in a 17 year old cat

Kate Richardson — Sat, 28 Jan 2012 19:45:46 GMT

[quote user="Michael Woodhouse"]

*coughs*

[quote user="Neil Wheadon"]Glucose 16.58

Differentials include, recent blood transfusion, fluid therapy, diabetes and hepatic lipidosis.[/quote]

[/quote]

They can have hypophosphataemia with diabetes, but it is when they are in ketoacidosis, so given the history of being a bit thin, polydipsic and intermittent vomiting the past 2 weeks, but eating ok, I think it's a good shout Micheal, and definitely worth rechecking BG and more importantly a urine sample.

I really think in cats a urine sample should be obtained as early as possible as part of your minimum database, it can tell you so much

Re: Hypophosphataemia in a 17 year old cat

Mark Hedberg — Sat, 28 Jan 2012 17:11:40 GMT

[quote user="Michael Woodhouse"]

[quote user="Mark Hedberg"]Stress hyperglycemia?[/quote]

Could be, but in these borderline cases I do fructosamine. Or atleast squeeze the bladder and get a urine glucose, IIRC ~12mmol/l is renal threshold. I have had diabetic cats in the high teens/low twenties. In my experience the 'stress' pushes them up but not that high. Only the vet taking the blood knows if it took 5 goes and 3 nurses to pin the cat down or If it sat there with minimal restraint.

I think it's rather high to just ignore.

[/quote]

Of course you're right in this case - I'm not saying "ignore the glucose" - just adding to differentials. He was saying none of them "fit" - I assume there's a reason for that.

Re: Hypophosphataemia in a 17 year old cat

Michael Woodhouse — Sat, 28 Jan 2012 15:07:33 GMT

[quote user="Mark Hedberg"]Stress hyperglycemia?[/quote]

I think it's rather high to just ignore.

Re: Hypophosphataemia in a 17 year old cat

Mark Hedberg — Sat, 28 Jan 2012 14:58:32 GMT

[quote user="Michael Woodhouse"]

*coughs*

[quote user="Neil Wheadon"]Glucose 16.58

Differentials include, recent blood transfusion, fluid therapy, diabetes and hepatic lipidosis.[/quote]

[/quote]

Stress hyperglycemia?

Re: Hypophosphataemia in a 17 year old cat

Michael Woodhouse — Sat, 28 Jan 2012 14:41:48 GMT

*coughs*

[quote user="Neil Wheadon"]Glucose 16.58

Differentials include, recent blood transfusion, fluid therapy, diabetes and hepatic lipidosis.[/quote]

Re: Hypophosphataemia in a 17 year old cat

Mark Lowrie — Sat, 28 Jan 2012 10:56:32 GMT

I agree with phipps. The hypophosphateamia is likely secondary to something else and even if this was causing weakness it wouldn't cause ataxia. Therefore I'd be looking for something that would cause central nervous system signs.

I second the plan to check BP as may be a hypertensive encephalopathy. In addition I'd also check urea/creatinine plus urine specific gravity. T4 also a good suggestion. These are good in-house tests that can be done easily. If this is all normal the next step would ideally be to consider advanced imaging although I appreciate this may not be easily accessible.

Re: Hypophosphataemia in a 17 year old cat

Rachael Winder — Sat, 28 Jan 2012 10:18:00 GMT

I would be certainly checking T4- have had a few cats with hyperT4 with low phosphate- never got to the bottom of why, even various medical specialists I spoke to only got as far as saying probably something to do with ion shifts caused by skewed metabolism.

Re: Hypophosphataemia in a 17 year old cat

Glen McIntosh — Sat, 28 Jan 2012 03:59:27 GMT

I would be surprised if the degree of hypophosphataemia seen in this cat was the cause of this cats symptoms. The textbooks say to start to get worried about hypophosphataemia if < 0.8, in terms of the appearance of clinical symptoms from hypophosphataemia, so in this case it is very borderline as to whether you should worry about treating the hypophosphataemia at all. I tend to only treat if <0.5 or so, or if I think the phosphate is likely to drop further, and I have only seen this during treatment of diabetic ketoacidosis and refeeding syndrome.

I would be looking at other causes of this cats presenting symptoms - ie the drunken gait. Was the owner with the cat the whole time leading up to the onset of the symptoms? If not, I would consider a seizure episode as a possibility, and the drunken gait could be a post ictal symptom (in which case it will probably resolve itself). In addition, hypophosphataemia can be causes by a shift of phosphate from the extracellular to the intracellular space due to consumption of ATP and then replenishment of ATP (which utilises phosphate). So any process that consumes a lot of ATP could lead to a mild to moderate temporary (and clinically unimportant) hypophosphataemia. A seizure is one such process. In fact, I often see hypophosphataemias of around this level in animals that have recently had documented seizures. A seizure might also explain mildly elevated lactate levels in an otherwise well perfused animal.

Moving away from the hypophosphataemia, I might also consider cerebral thromoembolism or a cerebrovascular accident as a cause of the cat's presenting symptoms. For the later, checking BP might be useful to identify hypertension as the underlying cause. Echocardiography might be helpful in identifying the former. Thyroid levels might also be worth looking at.

Is the PCV ok?

No nystagmus I gather?

Of course masterful inactivity and observation could well be indicated in this case to see if it gets better by itself with time, and perhaps repeating the phosphate level in a few hours before considering supplementation - I reckon it might have corrected itself. Certainly I reckon it is worth checking the BP tonight, but the T4 and echo could wait for the cats usual vet in the am, if still indicated.