Polycythaemia vera

Re: Polycythaemia vera

John Flynn — Tue, 10 Feb 2015 19:30:19 GMT

Just for completeness, Dr Google reports the following 95% reference intervals for healthy Grehounds sampled based on 151 patients run on Lasercyte:

HCT 42.7-61.5

Hgb 15.1-20.4

rbc 6.0-9.4

mcv 66-79

Re: Polycythaemia vera

Hannah Wynne Richards — Tue, 10 Feb 2015 18:58:52 GMT

PCV was 69.6, but after some of the other postings, I've decided to concentrate on it's heart. Thanks all the same

Wynne

Re: Polycythaemia vera

Martin Atkinson — Tue, 10 Feb 2015 16:38:25 GMT

Another one who doesn't think a PCV of 65% is excessively high for a greyhound. I'd be looking at investigating cardiac disease or other causes of weakness here before treating a spuriously high PCV with drugs. Any chance of finding a previous reading?

Re: Polycythaemia vera

Rob Davis — Tue, 10 Feb 2015 12:04:39 GMT

[quote user="shanley barber"]

Hi,

This certainly won't qualify as the 'latest thinking' but I had a Golden Retriever with polycythaemia vera about ten years ago, and we treated with hydroxyurea. I left the practice shortly after starting the dog on it, but i seemed to remember my colleague who took over the case saying that it responded well.

Hope that helps.

Shanley

[/quote]

The dog did indeed do well and stayed on hydroxyurea for several years before being euthanased for an unrelated condition.

I would question the diagnosis at this stage from the information given - HCT of 69% in a greyhound may not even be abnormal. From memory I think the case Shanley mentioned (a golden retriever) was around 78% at the time of diagnosis.

PS I think it was diagnosed nearer 15 years ago - you're older than you think!

Re: Polycythaemia vera

Hannah Wynne Richards — Tue, 10 Feb 2015 11:23:45 GMT

In other words, high normal, and concentrate on the heart.

Thanks everyone.

Wynne

Re: Polycythaemia vera

Kirsten Simpson — Tue, 10 Feb 2015 11:07:27 GMT

I'm prob being dumb here, but I was always taught that Greyhounds have a higher PCV than "normal" dogs so that wouldn't overtly worry me just now - I've seen healthy Greyhounds with a pcv of 65% no worries. The last Polycythemia dog we had also had Tetralogy of Fallot so needed bled every month (he would show clinical signs when it got above 65% though, he was a border terrier).

Re: Polycythaemia vera

Dagmar Steele — Tue, 10 Feb 2015 10:24:24 GMT

I had a case of PV a couple of years ago and when reading this up I came across the information that for greyhounds ridiculously high values were deemed to be normal. I didn't chime in earlier as you guys see a lot more greyhounds than I do in Germany (nil), but it has been lingering at the back of my brain ever since. Treatment back then was hydroxyurea for true PV.

Re: Polycythaemia vera

Hannah Wynne Richards — Tue, 10 Feb 2015 10:14:08 GMT

Her chest has been radiographed and is fine. Notched QRS complexes and episodes of atrial fibrillation before lanoxin was started.

Wynne

Re: Polycythaemia vera

Hannah Wynne Richards — Tue, 10 Feb 2015 09:23:44 GMT

Thanks everyone. The machine is an Idexx LaserCyte.

Wynne

Re: Polycythaemia vera

Christopher Saul — Mon, 09 Feb 2015 22:48:58 GMT

Hi Wynne,

Any condition that results in prolonged tissue hypoxia can result in a secondary / compensatory polycythaemia, so as Andy says, cardiac or respiratory disease can cause polycythemia. With cardiac disease it's usually the right to left shunting abnormalities that do this( so in a dog this age I guess it's unlikely), though the arrhythmia that you documented together with the cyanotic episode would make me worry that maybe there could be cardiac disease going on.

I'd be inclined to get a cardiac investigation done on this dog to be honest.

Also you mention the lungs are fine; I'm assuming you did thoracic radiography?

Renal tumours can produce erythropoietin; the absence of azotaemia on biochemistry would not eliminate this so renal ultrasound would also be a good idea

hope this helps

Chris

Re: Polycythaemia vera

John Flynn — Mon, 09 Feb 2015 21:54:24 GMT

[quote user="Hannah Wynne Richards"]RBC 9.3 HCT 69.6 HGB 20.3 MCHC 29.2 RDW 14.6 WBC 4.98.[/quote]

What anaylser did you use?

These are some reference intervals courtesy of Dr Google based on 48 Greyhounds run on a "Procyte", your results are likely representative of an average greyhound I suspect?

HCT 51.5-71%

Hgb 17.4-24.1

RBC 7.4-10.2

I can't find a reference interval for any analyser that does not include 20.3 Hgb.

Re: Polycythaemia vera

John Flynn — Mon, 09 Feb 2015 21:30:03 GMT

[quote user="Hannah Wynne Richards"]HCT 69.6[/quote]

Unless your eyesight is better than mine, that looks like an automated haematology machine output - have you confirmed with a couple of manual PCV's? If so, what were those figures?

Re: Polycythaemia vera

Hannah Wynne Richards — Mon, 09 Feb 2015 15:02:39 GMT

If I go for hydroxurea, what is the dose?

Wynne

Re: Polycythaemia vera

Hannah Wynne Richards — Mon, 09 Feb 2015 15:01:29 GMT

She did have a weird chaotic heart rhythm, but this has settled down on lanoxin, however the polycythaemia has contnued. She's had one episode of collapse with cyanosis, which I put down to a pulmonary embolism,but otherwise lungs fine. Biochem fine. The microcytic polycythaemia makes me think this is a failure of red cell breakdown, rather than overproduction. The owner has looked up her racing form. She did very well, then had a sudden drop in performance, so went for rehoming- possible cardiac episode?

Wynne

Re: Polycythaemia vera

Kate Richardson — Mon, 09 Feb 2015 14:41:48 GMT

What symptoms is it showing?

Re: Polycythaemia vera

Andrew Kent — Mon, 09 Feb 2015 12:17:55 GMT

Hi Wynne,

Are you sure this is a primary polycythemia rather than secondary (i.e. have you excluded heart disease, respiratory disease, renal disease, endocrine disease, dehydration etc?). In this breed it can be a harder call to make with normal HCT's up to 65.

Otherwise if it is a primary polycythemia most people will perform phlebotomy first and then assess the need for other medications based on how long the benefit lasts for. Hydroxyurea is the most widely used drug.

Hope that helps,

Andy

Re: Polycythaemia vera

shanley barber — Mon, 09 Feb 2015 12:14:41 GMT

Hi,

Hope that helps.

Shanley