13 year old son with possible mitochondrial disorder

I have a 13 year old son.  He was perfectly normal untill about the age of 4 when he started having terrible leg pain. (not growing pains).  After many tests we finally had a neurologist tell us that he had mild CP, but not enough to totally account for how bad the leg pain was.  He would scream and cry all night nothing seemed to help.  Then he started seeming like he was in a fog all the time, he would frget things and his eyes just seemed to be glazed.  Finally they tested and determined that he was having complex partial seizures (most of them in his sleep) this is why we did not see the actual seizure.  We started treating him and after about a year got him on the right medicine and dose and the seizures and leg pain decreased somewhat.  However we were struggling with his weight and recurrent infections of different kinds.  Which affected the seizure actifity.  
He would have episodes of memory loss and forget things that had taken him months to learn.  And then never seem to be able to relearn the forgotten information although he could learn new things.  W
We continued to struggle with his weight and had him on Pediasure over the years although it was difficult to get him to drink it.  When he was 10 he weighed only 40lbs.  He was in and out of the hospital often for dehydration, and vomiting, but they could never find anything.  Finally about 3 years ago he started throwing up everyday sometimes all day long.  This went on for 3 months in and out of the hospital and testing going on the whole time.  Finally they found a small obstruction on his stomach (SMA Syndrome or Superior Mesenteric Artery Syndrome).  However they could only see it when he was laying down.  
He was put on an NG tube for feedings.  At that time I was told in 2-3 months his weight would be back up to  normal and we would remove the tube.  However it has been over 3 years.  We have graduated from the NG tube to a G button.  His weight is now closer to normal and we havent been in the hospital for dehydration, but he is unable to maintain a healthy body weight without the tube feedings.  Even though he new eats normally.  
A few other things that might be significant.  In the last 2 years he has developed a wandering eye.  He has characteristics of a child with Aspergers (although there hasn't been an official d/x) and he has had 2 kidney stones age 8 and 10 that were analyzed to be made of ammonia (which baffled the urologist).  
Untill now all of these have been treated as seperate entities.  However I took him last week to be evaluated for his learning disability, regression in school (ie can not read and has forgotten most things he learned), and possible Aspergers.  The Dr there kept asking questions about his health issues as if they were all part of one big issure rather than seperate.  She suggested that he might have a mitochondrial disorder and that we have some genetic testing done, without any further explenation.  I came home and read up and some of the information is terrifying.  However I don't want to jump the guy untill we know for sure.  I am just wondering if there would be a source where I could get some more reliable information, or if all of this sounded like it could infact be related in some way.  I know this is long but felt that it all may be important.  Thanks

[mmom9495]

i should also mention that he has weak muscle tone due to his CP,  is heat and cold intollerent, and gets tired very easily.