Autism spectrum disorders associated to a deficiency of the enzymes of the mitochondrial respiratory chain.

Autism spectrum disorder (ASD) is a group of neurodevelopmental disorders characterized by a combination of reciprocal social deficits, communication impairment, and rigid ritualistic interest and stereotypies. The etiology is generally multifactorial, including genetic, immunological and/or environmental factors. A group of ASD has been linked to mitochondrial dysfunction with subsequent deficiency in energy production. Patients with ASD and mitochondrial disease often show signs and symptoms uncommon to idiopathic ASD such as cardiac, pancreatic or liver dysfunction, cardiac, growth retardation, fatigability, but in some cases semiology is different. We show two clinical cases of ASD associated to a deficiency of the mitochondrial respiratory chain (complex I+III and IV) with different clinical presentations. In one case, signs and symptoms of mitochondrial disorder were mild and the second diagnosis was attained many years after that of ASD. These findings support the recent growing body of evidence that ASD can be associated with mitochondrial disorder. Children with ASD and abnormal neurologic or systemic findings should be evaluated for mitochondrial disorder.

Relationship between adipic acid concentration and the core symptoms of autism spectrum disorders.

Dicarboxylic acids are an important source of information about metabolism and potential physiopathological alterations in children with autism spectrum disorders (ASDs). We measured the concentration between dicarboxylic adipic and suberic acids in children with an ASD and typically-developing (TD) children and analyzed any relationships between the severity of the core symptoms of ASDs and other clinical features (drugs, supplements, drugs, or diet). The core symptoms of autism were evaluated using the DSM-IV criteria, and adipic acid and suberic acid were measured in urine samples. Overall, no increase in the concentration of adipic acid in children with ASDs compared to TD children, however when considering vitamin B supplementation in ASD there were significantly increased level of urinary adipic acid in children with an ASD not taking vitamin B supplementation compared to supplemented children or to TD children. No significant difference were observed in suberic acid. Interestingly, the increase in adipic acid concentration was significantly and indirectly correlated with the severity of the deficit in socialization and communication skills in children with an ASD. Therefore, therapeutic treatments aimed at decreasing adipic acid concentration might not be beneficial for treating the core symptoms of ASDs.

Lead excretion in spanish children with autism spectrum disorder.

Among epigenetic factors leading to increased prevalence of juvenile neuropsychiatric disorders, including autism spectrum disorder, exposure to metals, such as lead (Pb) have led to conflicting results. The aim of the present study was to determine the levels of Pb in the urine of children with autism spectrum disorder (ASD) compared with typically developing children (TD) age- and sex-matched, and to analyze any association between core symptoms of ASD, special diets, supplements intake or prescription drugs and the concentration of Pb. The study was performed in a group of children with ASD (n = 35, average age 7.4 ± 0.5 years) and TD (n = 34, average age 7.7 ± 0.9 years). Measurement of lead in urine was performed by atomic absorption spectrometry; symptoms of ASD were analyzed by diagnostic and statistical manual of mental disorders (DMS-IV) using the questionnary ADI-R. Careful clinical evaluation was also undertaken and statistical analysis was done taking into account any possible confounding factor.

Increased homocysteine levels correlate with the communication deficit in children with autism spectrum disorder.

The clinical significance of high levels of homocysteine in autism spectrum disorder (ASD) is unknown. An experimental study was conducted in order to evaluate the concentration of homocysteine in children with ASD and typically developing children and to analyse any relationships with the severity of core symptoms of ASD and other clinical features (drugs, co-morbidities, gender, age, diet). Core symptoms of autism were evaluated by DSM-IV criteria. Homocysteine, glutathione, methionine, 3-nitrotyrosine were measured in urine. The increase in homocysteine concentration was significantly and directly correlated with the severity of the deficit in communication skills, but was unrelated to deficit in socialisation or repetitive/restricted behaviour. Urinary homocysteine concentration may be a possible biomarker for communication deficits in ASD and a potential diagnostic tool useful to evaluate new treatment options since no treatment for core symptoms of ASD are available.