From Health Lover, Ilena Rosenthal:
www.ilenarose.blogspot.com

 Dev Med Child Neurol. 2005 Mar;47(3):148.  
http://www.ncbi.nlm.nih.gov/pubmed/15739723?ordinalpos=1&itool=EntrezSystem2.PEn
trez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA

Mitochondrial dysfunction in autism spectrum disorders: a
population-based study.
Oliveira G, Diogo L, Grazina M, Garcia P, Ataíde A, Marques C, Miguel
T, Borges L, Vicente AM, Oliveira CR.

Outpatient Clinic of Autism, Centro de Desenvolvimento da Criança,
Hospital Pediátrico de Coimbra, 3000-076 Coimbra, Portugal.

A minority of cases of autism has been associated with several
different organic conditions, including bioenergetic metabolism
deficiency.

In a population-based study, we screened associated medical
conditions in a group of 120 children with autism (current age range
11y 5mo to 14y 4mo, mean age 12y 11mo [SD 9.6mo], male:female ratio
2.9:1). Children were diagnosed using Diagnostic and Statistical
Manual of Mental Disorders criteria, the Autism Diagnostic
Interview--Revised, and the Childhood Autism Rating Scale; 76% were
diagnosed with typical autism and 24% with atypical autism. Cognitive
functional level was assessed with the Griffiths scale and the
Wechsler Intelligence Scale for Children and was in the normal range
in 17%. Epilepsy was present in 19 patients. Plasma lactate levels
were measured in 69 patients, and in 14 we found hyperlactacidemia.

Five of 11 patients studied were classified with definite
mitochondrial respiratory chain disorder, suggesting that this might
be one of the most common disorders associated with autism (5 of 69;
7.2%) and warranting further investigation.