EMG conduction block and acetylcholine antibodies

Status
Not open for further replies.

mikej2323

Member
Joined
Mar 5, 2007
Messages
17
Reason
PALS
Country
US
State
IA
City
Indianola
Wondering if anyone had a conduction block on their EMG and if they tested positive for antibodies against acetylchline? {MG has been ruled out}.

Thanks.

Mike
[email protected]
 
mikej2323 said:
Wondering if anyone had a conduction block on their EMG and if they tested positive for antibodies against acetylchline? {MG has been ruled out}.

Thanks.

Mike
[email protected]

I had conduction block in one of 20 pairs (apparently not considered significant) and my AChR antibodies were negative. I have read, though, that AChR antibodies will, uncommonly, give a false positive reading in ALS.
 
So Meg, have you been diagnosed with ALS?
 
mikej2323 said:
So Meg, have you been diagnosed with ALS?

Yes, in 2003. Which I know seems odd since this forum seems to have recently turned into the I'm-scared-I've-got-it-but-my-doc-sez-I-don't board.
 
Well, it seems odd- I've read the majority of PALS do not have a conduction block and do not test positive for acetylcholine antibodies. Also, don't PALS have primarily "brisk" reflexes?

Mike
[email protected]
 
mikej2323 said:
Well, it seems odd- I've read the majority of PALS do not have a conduction block and do not test positive for acetylcholine antibodies. Also, don't PALS have primarily "brisk" reflexes?

Mike
[email protected]

I don't understand where you're going with your comments. It's probably true that the majority of PALS don't have conduction block and it's certainly true that the majority don't test positive for AChR antibodies, but conduction block on one pair is not at all unusual, falling well within the range of normal. And, yes, until they are largely disabled, PALS's reflexes are brisk.

Something tells me there's another question on your mind that you haven't asked.
 
Hi Mike -

Do you have ALS or do you just need to edit your user profile?

Liz
 
Nope, I have not been diagnosed with ALS. My 11-year old niece (identical twin) two years ago, began having shoulder and arm weakness. This progressed to decreased arm function and eventually a foot drop. This then went to the other side. She is now on a ventilator. I'm just searching for answers. Some of the things I have come across, but not proven, is a conduction block and loss of reflexes are not present in PALS as well as antobodies to acetycholine.
Her reflexes degenerated along with the non-use of her extremities. I've read that reflexes are brisk in PALS and therefore, no conduction block is present.

Just trying to find answers.

Mike
 
mikej2323 said:
Nope, I have not been diagnosed with ALS. My 11-year old niece (identical twin) two years ago, began having shoulder and arm weakness. This progressed to decreased arm function and eventually a foot drop. This then went to the other side. She is now on a ventilator. I'm just searching for answers. Some of the things I have come across, but not proven, is a conduction block and loss of reflexes are not present in PALS as well as antobodies to acetycholine.
Her reflexes degenerated along with the non-use of her extremities. I've read that reflexes are brisk in PALS and therefore, no conduction block is present.

Just trying to find answers.

Mike

Actually, while PALS's reflexes are brisk early in the disease (during the diagnostic process), as limbs weaken and atrophy, reflexes eventually largely disappear. Quite frankly, FWIW, I've never heard that conduction block is associated exclusively with diminished reflexes. Also, it's pretty well known that ALS can cause a false-positive in the AChR test:

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=3479935&dopt=Abstract
 
Well, I wasn't trying to correlate conduction block and diminished reflexes- sorry if it sounded that way. Interesting study you posted, however, it is just one study and it was 20 years ago...do you know of any more?
It seems strange that an 11-year old identical twin goes from playing sports to not walking anymore in 8 months! I cannot figure this out...?
 
mikej2323 said:
Well, I wasn't trying to correlate conduction block and diminished reflexes- sorry if it sounded that way. Interesting study you posted, however, it is just one study and it was 20 years ago...do you know of any more?

Do you think the study was done incorrectly? The results are no secret--it's pretty much accepted that a small percentage of PALS will test positive for MG when they don't have it. You can google as well as I can if you want to know more. Or just ask your niece's doctor (assuming he's a neuromuscular expert). But what's the problem with a 20 year old study of an observed phenomenon? I can see the complaint if we were evaluating a medication for effectiveness because the variables could certainly change in 20 years but I can't imagine why 20 year old data wouldn't be good for something like this. You know, once something is pretty well settled by science, there's little point in continuing to test the hypothesis. At the very least--who'd want to fund a settled question?
 
Status
Not open for further replies.
Back
Top