The main test is a muscle biopsy I believe.

And mito can also cause gastroparesis.

http://my.clevelandclinic.org/disord...l_Disease.aspx

It used to be thought that one had to present with this as a child. But recent thinking is showing that it can appear in adults, either as a recessive gene that becomes more active,
or as acquired from damage from the environment (drugs, toxins and infections).

I made this post in response the the new article that appeared in Science News recently....
http://neurotalk.psychcentral.com/sh...t=mitochondria

When extreme, this disorder can have dramatic symptoms. But when milder, it can be overlooked.

Because the autism community is working on this aspect of it as a potential cause of autism, attention in the press is becoming more obvious.

If you read the article from the Cleveland Clinic, you can see the nutrients used to treat this.

Your swift response to acetyl carnitine suggests that your mitochondria may be not functioning well for some reason.