I just joined and I know your question was posted awhile back, but I would encourage anyone who has a child with an autism diagnosis to check out the UMDF website to see if your child has any of the symptoms. It also has great advice as to the testing that is needed. I do know that a metabolic panel was run for our daughter but, this was done through Kennedy Krieger Institute in Maryland and not all doctors run these tests as the norm. It is worth finding out. There is no cure for mitochondrial disease, you basically are treating the symptoms as they come up. Hypothyroidism, autistic like symptoms, diabetes, stomach issues, lack of energy are just some of the possible symptoms. My daughter was originally diagnosed as having severe autism, or classic autism and has stomach issues constantly and energy problems. The one thing that sometimes helps is called a mitochondrial cocktail which can increase the way cells use energy. It is worth going to a genetics doctor if anything unusual comes up in the metabolic panel. I would just recommend going to doctors that insurance covers. I am all for natural health, but with kids with mitochondrial disease you really need to have blood tests done to see what they are deficient in and not just guess. Some of the supplements in too high a dose can cause more harm than good.

My DD is on the waiting list for the pediatric neurometabolic clinic in our area. She responded very well to acetyl-l-carnitine and Coenzyme Q10, which are part of the "mito cocktail".

My son is getting treated with Dr. Goh. She is an amazing neurologist who works with kids with mitochondrial dysfunction. She has created a cocktail for the dysfunction called Mitospectra. I found it to be the most complete supplement available for treatment.
This doctor is in San Diego. She is extremely knowledgable and helpful.
Have you checked your daughter's creatinine levels? If it's shown consistently low the. It could be a mitochondrial dysfunction and that could be causing the fatigue.
Best of luck to you. Keep us updated

Our daughters neurologist has suspected "mito" since she was 2yrs old as she has ataxia, hypotonia, global delays and high levels of lactic acid in her blood which means her cells are not getting enouph energy from her mitochondria. They did a muscle biopsy and didn't show anything unusual. She was also diagnosed with ASD last April at 4yrs old and decided to test her again last month for "mito" with a DNA test. Still waiting on results. She is very hyper for a day or two then is very tired the next day or two. She is on tenex to help her sleep but she still goes through this stages of high and low energy.

Arkansas Children's Hospital has a Genetics and Metabolics Clinic. They may or may not have a mito specialist on staff, but they should be able to do the basic lab testing to see if she has any "red flags" for mito. http://www.archildrens.org/Services/Genetic-and...