PSSM Help!

[Mahoganybay]

so good if you are finding the right management regime for her. It would be interesting to know your test results idc.

I know, I am literally on email watch day and night waiting for the results.

 

[indie1282]

I consulted a independent equine nutritionist, sending a full history including photos of my mare. She suspects PSSM2, as does my physio ?

I started her as advised on a diet and exercise regime for a PSSM2 horse and have sent off a hair sample to CAG in Germany. Just awaiting results.

Not sure what results I want really, she is doing really well on the diet/exercise but she has had some mechanical lameness issues that have been resolved too so it may be a coincidence ?‍

Whatever the results, she looks and feels super at the moment however I am dreading winter as that is when she stiffens and shows symptoms.

I have the physio back out on the 16.7.20 and I should have my CAG results by then and we can make a plan ?

My horse is suspected PSSM 2, would you be able to let me know how you are feeding her please? PM if you would prefer. He is a 15 year old WB gelding.

 

[Mahoganybay]

so good if you are finding the right management regime for her. It would be interesting to know your test results idc.

Received test results last night from CAG:

Polysaccharide Storage Myopathy 2 (PSSM2) Myofibrillar Myopathy (MFM) Recurrent Exertional Rhabdomyolysis (RER)
P2 - n/n
P3 - n/n
P4 - n/n
Px - n/n

With that result it seems my horses issues have most likely been due to the mechanical lameness it took 18 months to get to the bottom of and treat accordingly.

I will be keeping a very close eye on her going into winter and will still be coming up with a plan of action with my physio.

But, phew ?

 

[SEL]

Received test results last night from CAG:

Polysaccharide Storage Myopathy 2 (PSSM2) Myofibrillar Myopathy (MFM) Recurrent Exertional Rhabdomyolysis (RER)
P2 - n/n
P3 - n/n
P4 - n/n
Px - n/n

With that result it seems my horses issues have most likely been due to the mechanical lameness it took 18 months to get to the bottom of and treat accordingly.

I will be keeping a very close eye on her going into winter and will still be coming up with a plan of action with my physio.

But, phew ?

Good going! Haven't seen many that are clear across the board. Hopefully you can get the other issues sorted.

 

[shortstuff99]

Received test results last night from CAG:

Polysaccharide Storage Myopathy 2 (PSSM2) Myofibrillar Myopathy (MFM) Recurrent Exertional Rhabdomyolysis (RER)
P2 - n/n
P3 - n/n
P4 - n/n
Px - n/n

With that result it seems my horses issues have most likely been due to the mechanical lameness it took 18 months to get to the bottom of and treat accordingly.

I will be keeping a very close eye on her going into winter and will still be coming up with a plan of action with my physio.

But, phew ?

I would make sure to do your research on this test, a negative genetic test does not exclude PSSM 2. Only around 50% of confirmed cases have one of these genetic indicators. If you still suspect PSSM 2 I would have a muscle biopsy as that will tell you for sure.

 

[ycbm]

PSSM management is basically:-
warmth/rugs
constant movement (not stabled)
frequent exercise
vit E and people usually add salt/magox and possibly a supplement
and then diet depending on which type you are dealing with. Low sugar'starch, For PSSM 2 more protein/tri aminos for PSSM 1 fats or alcar.

but they are all different and it is trial and error to see what works.

I had a (untested) PSSM 2 horse who responded brilliantly to alcar. His tight muscles deflated like a popped balloon. It's a tricky disease, isn't it?

I'm disappointed to read those late onset ages, though. My appy, who is obviously higher risk due to his breeding, is only 5 and I thought I was safe because the other had symptoms at 4

.

 

[Mahoganybay]

I would make sure to do your research on this test, a negative genetic test does not exclude PSSM 2. Only around 50% of confirmed cases have one of these genetic indicators. If you still suspect PSSM 2 I would have a muscle biopsy as that will tell you for sure.

Yes, I’m aware. Without the full history of my mares lameness and treatments I would have strongly suspected PSSM2.

We have had her soft & supple through her body when the lameness has been masked with steroids, only for them to wear off and shes sore all over again.

Hopefully now we have got to the right treatment (in Feb) she’s at rehab livery and working correctly, with better turnout, physio/remedial farrier and professional dressage rider assisting she has turned a corner.

I have armed myself now with so much information about PSSM2 that i feel I can take parts of the management of it and apply it to my mare anyway I.e. diet, exercise and adequate rugging.

 

[shortstuff99]

Yes, I’m aware. Without the full history of my mares lameness and treatments I would have strongly suspected PSSM2.

We have had her soft & supple through her body when the lameness has been masked with steroids, only for them to wear off and shes sore all over again.

Hopefully now we have got to the right treatment (in Feb) she’s at rehab livery and working correctly, with better turnout, physio/remedial farrier and professional dressage rider assisting she has turned a corner.

I have armed myself now with so much information about PSSM2 that i feel I can take parts of the management of it and apply it to my mare anyway I.e. diet, exercise and adequate rugging.

My fingers are crossed for you that it all works out!

I probably sound like I have a bee in my bonnet about the PSSM 2 test but as a geneticist the science behind it really annoys me and there is a reason why the test has not been licensed.

 

[Mahoganybay]

My fingers are crossed for you that it all works out!

I probably sound like I have a bee in my bonnet about the PSSM 2 test but as a geneticist the science behind it really annoys me and there is a reason why the test has not been licensed.

I’m keeping everything crossed too ??

I will certainly look at the biopsy should we need to.

 

[paddy555]

If you still suspect PSSM 2 I would have a muscle biopsy as that will tell you for sure.

yet as with everything there seems the possibility for doubt.

A diagnosis of PSSM2 is made from a muscle biopsy. PAS stains for glycogen reveal aggregates of amylase-sensitive PAS positive material, likely glycogen, clumped in the cytoplasm of the muscle fiber and under the cell membrane. This is a subjective evaluation of the amount and location of the aggregates because glycogen is a normal part of the muscle cell. A false positive diagnosis can occur if the muscle biopsy is crushed with forceps resulting in abnormal glycogen and a false negative diagnosis can occur if samples are not kept chilled and shipped quickly to the laboratory because glycogen is degraded while the muscle biopsy is in transport. There is also overlap in the appearance of muscle biopsies of horses with PSSM2 and RER. The amount of abnormal glycogen is graded as mild, moderate and severe PSSM2. This does not always correlate with prognosis or severity of clinical signs. A diagnosis of mild PSSM2 lies in a gray area in which that amount of glycogen could be normal for an equine athlete and it is essential that horses with a diagnosis of mild PSSM2 have a full lameness and medical examination to ensure there is not another basis for their exercise intolerance.

 

[shortstuff99]

yet as with everything there seems the possibility for doubt.

A diagnosis of PSSM2 is made from a muscle biopsy. PAS stains for glycogen reveal aggregates of amylase-sensitive PAS positive material, likely glycogen, clumped in the cytoplasm of the muscle fiber and under the cell membrane. This is a subjective evaluation of the amount and location of the aggregates because glycogen is a normal part of the muscle cell. A false positive diagnosis can occur if the muscle biopsy is crushed with forceps resulting in abnormal glycogen and a false negative diagnosis can occur if samples are not kept chilled and shipped quickly to the laboratory because glycogen is degraded while the muscle biopsy is in transport. There is also overlap in the appearance of muscle biopsies of horses with PSSM2 and RER. The amount of abnormal glycogen is graded as mild, moderate and severe PSSM2. This does not always correlate with prognosis or severity of clinical signs. A diagnosis of mild PSSM2 lies in a gray area in which that amount of glycogen could be normal for an equine athlete and it is essential that horses with a diagnosis of mild PSSM2 have a full lameness and medical examination to ensure there is not another basis for their exercise intolerance.

Yes as with everything, but that coupled with the presentation of the horse is a better indicator then a genetic test that has not been proved to even be the correctly (or only) linked genes (hence why it hasn't been approved for use).

 

[paddy555]

Yes as with everything, but that coupled with the presentation of the horse is a better indicator then a genetic test that has not been proved to even be the correctly (or only) linked genes (hence why it hasn't been approved for use).

I was just pointing out that nothing was certain in trying to establish PSSM2 neither biopsy nor genetic testing.

 

[paddy555]

I had a (untested) PSSM 2 horse who responded brilliantly to alcar. His tight muscles deflated like a popped balloon. It's a tricky disease, isn't it?

I'm disappointed to read those late onset ages, though. My appy, who is obviously higher risk due to his breeding, is only 5 and I thought I was safe because the other had symptoms at 4

.

yes, sitting time bomb

you could PSSM1 test to rule that out.