Metabolic approaches to the treatment of autism spectrum disorders

Inborn Errors of Purine Salvage and Catabolism

Cellular purine nucleotides derive mainly from de novo synthesis or nucleic acid turnover and, only marginally, from dietary intake. They are subjected to catabolism, eventually forming uric acid in humans, while bases and nucleosides may be converted back to nucleotides through the salvage pathways. Inborn errors of the purine salvage pathway and catabolism have been described by several researchers and are usually referred to as rare diseases. Since purine compounds play a fundamental role, it is not surprising that their dysmetabolism is accompanied by devastating symptoms. Nevertheless, some of these manifestations are unexpected and, so far, have no explanation or therapy. Herein, we describe several known inborn errors of purine metabolism, highlighting their unexplained pathological aspects. Our intent is to offer new points of view on this topic and suggest diagnostic tools that may possibly indicate to clinicians that the inborn errors of purine metabolism may not be very rare diseases after all.

Urinary metabolomics using gas chromatography-mass spectrometry: potential biomarkers for autism spectrum disorder

BACKGROUND

Diagnosis of autism spectrum disorder (ASD) is generally made phenotypically and the hunt for ASD-biomarkers continues. The purpose of this study was to compare urine organic acids profiles of ASD versus typically developing (TD) children to identify potential biomarkers for diagnosis and exploration of ASD etiology.

METHODS

This case control study was performed in the Department of Pathology and Laboratory Medicine in collaboration with the Department of Pediatrics and Child Health, Aga Khan University, Pakistan. Midstream urine was collected in the first half of the day time before noon from the children with ASD diagnosed by a pediatric neurologist based on DSM-5 criteria and TD healthy controls from August 2019 to June 2021. The urine organic acids were analyzed by Gas Chromatography-Mass Spectrometry. To identify potential biomarkers for ASD canonical linear discriminant analysis was carried out for the organic acids, quantified in comparison to an internal standard.

RESULTS

A total of 85 subjects were enrolled in the current study. The mean age of the ASD (n = 65) and TD groups (n = 20) was 4.5 ± 2.3 and 6.4 ± 2.2 years respectively with 72.3% males in the ASD group and 50% males in the TD group. Parental consanguinity was 47.7 and 30% in ASD and TD groups, respectively. The common clinical signs noted in children with ASD were developmental delay (70.8%), delayed language skills (66.2%), and inability to articulate sentences (56.9%). Discriminant analysis showed that 3-hydroxyisovalericc, homovanillic acid, adipic acid, suberic acid, and indole acetic were significantly different between ASD and TD groups. The biochemical classification results reveal that 88.2% of cases were classified correctly into ASD& TD groups based on the urine organic acid profiles.

CONCLUSION

3-hydroxy isovaleric acid, homovanillic acid, adipic acid, suberic acid, and indole acetic were good discriminators between the two groups. The discovered potential biomarkers could be valuable for future research in children with ASD.

Altered Gut Microbiota in a Fragile X Syndrome Mouse Model

The human gut microbiome is the ecosystem of microorganisms that live in the human digestive system. Several studies have related gut microbiome variants to metabolic, immune and nervous system disorders. Fragile X syndrome (FXS) is a neurodevelopmental disorder considered the most common cause of inherited intellectual disability and the leading monogenetic cause of autism. The role of the gut microbiome in FXS remains largely unexplored. Here, we report the results of a gut microbiome analysis using a FXS mouse model and 16S ribosomal RNA gene sequencing. We identified alterations in the fmr1 KO2 gut microbiome associated with different bacterial species, including those in the genera Akkermansia, Sutterella, Allobaculum, Bifidobacterium, Odoribacter, Turicibacter, Flexispira, Bacteroides, and Oscillospira. Several gut bacterial metabolic pathways were significantly altered in fmr1 KO2 mice, including menaquinone degradation, catechol degradation, vitamin B6 biosynthesis, fatty acid biosynthesis, and nucleotide metabolism. Several of these metabolic pathways, including catechol degradation, nucleotide metabolism and fatty acid biosynthesis, were previously reported to be altered in children and adults with autism. The present study reports a potential association of the gut microbiome with FXS, thereby opening new possibilities for exploring reliable treatments and non-invasive biomarkers.

Sulfur amino acid metabolism and related metabotypes of autism spectrum disorder: A review of biochemical evidence for a hypothesis

There are multiple lines of evidence for an impaired sulfur amino acid (SAA) metabolism in autism spectrum disorder (ASD). For instance, the concentrations of methionine, cysteine and S-adenosylmethionine (SAM) in body fluids of individuals with ASD is significantly lower while the concentration of S-adenosylhomocysteine (SAH) is significantly higher as compared to healthy individuals. Reduced methionine and SAM may reflect impaired remethylation pathway whereas increased SAH may reflect reduced S-adenosylhomocysteine hydrolase activity in the catabolic direction. Reduced SAM/SAH ratio reflects an impaired methylation capacity. We hypothesize multiple mechanisms to explain how the interplay of oxidative stress, neuroinflammation, mercury exposure, maternal use of valproate, altered gut microbiome and certain genetic variants may lead to these SAA metabotypes. Furthermore, we also propose a number of mechanisms to explain the metabolic consequences of abnormal SAA metabotypes. For instance in the brain, reduced SAM/SAH ratio will result in melatonin deficiency and hypomethylation of a number of biomolecules such as DNA, RNA and histones. In addition to previously proposed mechanisms, we propose that impaired activity of "radical SAM" enzymes will result in reduced endogenous lipoic acid synthesis, reduced molybdenum cofactor synthesis and impaired porphyrin metabolism leading to mitochondrial dysfunction, porphyrinuria and impaired sulfation capacity. Furthermore depletion of SAM may also lead to the disturbed mTOR signaling pathway in a subgroup of ASD. The proposed "SAM-depletion hypothesis" is an inclusive model to explain the relationship between heterogeneous risk factors and metabotypes observed in a subset of children with ASD.

Identification of gender-related metabolic disturbances in autism spectrum disorders using urinary metabolomics

Autism spectrum disorders (ASD) are a highly heterogeneous group of neurodevelopmental disorders that are more commonly diagnosed in boys than in girls. The reasons for gender differences in ASD are unknown and no definitive current evidence can explain male predominance. Therefore, in search for laboratory biomarkers responsible for ASD, a comprehensive metabolomics study was performed by metabolic profiling of urine samples in 51 ASD subjects and 51 age- and sex-matched children with typical development. Orthogonal partial least-squares discriminant analysis (OPLS-DA) models with poor quality failed to perform the analysis based on gender in the ASD and control groups. OPLS-DA models based on single-sex samples, especially in female subjects, had better clustering between the ASD and control groups with an increase in the R² and Q² values compared with those in the whole group. Significantly increased levels of adenine, 2-Methylguanosine, creatinine, and 7alpha-hydroxytestololactone and a decrease in creatine were observed in the female ASD subjects. In particular, 7alpha-hydroxytestololactone, which has a structure similar to that of testolactone, was positively correlated with adenine (Pearson correlation coefficient, r = 0.738, p < 0.01), creatinine (r = 0.826, p < 0.01), and 2-Methylguanosine (r = 0.757, p < 0.01) and negatively correlated with creatine (r=-0.413, p < 0.05). A receiver operating characteristic curve analysis using the creatinine:creatine ratio yielded an area under the curve of 0.913 (95% CI: 0.806-1). These metabolites may be sex-related or sex-sensitive to an extent and can be valuable for identification of the molecular pathways involved in the gender bias in manifestation of ASD. The creatinine:creatine ratio has a potential to be a good predictor of ASD in the female subjects.

A modified ketogenic gluten-free diet with MCT improves behavior in children with autism spectrum disorder

Purpose

The ketogenic diet is a low-carbohydrate, moderate protein, high-fat diet that has emerged as a potential treatment for autism spectrum disorder. Autism spectrum disorder is a neurodevelopmental disorder of social communication, and restricted, repetitive behaviors and interests in need of novel therapies. An open-label clinical trial was done in Honolulu, Hawaii to test a modified ketogenic diet for improvement of core clinical impairments in children with ASD.

Intervention

A modified ketogenic gluten-free diet regimen with supplemental MCT was completed in 15 children ages 2 to 17 years for 3 months. Clinical (ADOS-2, CARS-2) and biochemical measures were performed at baseline and 3-months on the ketogenic diet.

Main outcome

Children administered a modified ketogenic gluten-free diet with supplemental MCT significantly improved core autism features assessed from the ADOS-2 after 3 months on diet (P = 0.006). No significant difference was observed in restricted and repetitive behavior score (P = 0.125) after 3 months on the diet protocol. Substantial improvement (> 30% decrease ADOS-2 total score) was observed in six participants, moderate improvement (> 3 units) in two participants, and minor/no improvement in seven participants. Ten participants assessed at a six-month time point sustained improvement in total ADOS-2 and social affect subdomain scores comparing baseline and 6 months (P = 0.019; P = 0.023), but no significant improvement in restricted and repetitive behavior scores were noted (P = 0.197). Significant improvements in CARS-2 items after 3 months of the modified ketogenic protocol were observed in imitation, body use, and fear or nervousness (P = 0.031, P = 0.008, P = 0.039). The percent change on ADOS-2 score from baseline to 3 months was associated with baseline high-density lipoprotein levels (ρ = −0.67, P = 0.007) and albumin levels (ρ = −0.60, P = 0.019). Moreover, the percent change from baseline to 3 months in ADOS-2 scores was significantly associated with percent change in high-density lipoprotein levels (ρ = 0.54, P = 0.049) and albumin levels (ρ = 0.67, P = 0.010).

Conclusions

A modified gluten-free ketogenic diet with supplemental MCT is a potentially beneficial treatment option to improve the core features of autism spectrum disorder and warrants further investigation.

Trial registration

Trial Registry: Clinicaltrials.gov Registration Number: NCT02477904 URL: https://www.clinicaltrials.gov/ct2/show/NCT02477904?term=ketogenic+diet&cond=Autism&rank=1

Clinical Genetic Aspects of ASD Spectrum Disorders

Early presumptions opined that autism spectrum disorder (ASD) was related to the rearing of these children by emotionally-distant mothers. Advances in the 1960s and 1970s clearly demonstrated the biologic basis of autism with a high heritability. Recent advances have demonstrated that specific etiologic factors in autism spectrum disorders can be identified in 30%–40% of cases. Based on early reports newer, emerging genomic technologies are likely to increase this diagnostic yield to over 50%. To date these investigations have focused on etiologic factors that are largely mono-factorial. The currently undiagnosed causes of ASDs will likely be found to have causes that are more complex. Epigenetic, multiple interacting loci, and four dimensional causes (with timing as a variable) are likely to be associated with the currently unidentifiable cases. Today, the “Why” is more important than ever. Understanding the causes of ASDs help inform families of important issues such as recurrence risk, prognosis, natural history, and predicting associated co-morbid medical conditions. In the current era of emerging efforts in “personalized medicine”, identifying an etiology will be critical in identifying endo-phenotypic groups and individual variations that will allow for tailored treatment for persons with ASD.

AMPD1 functional variants associated with autism in Han Chinese population

Autism is a childhood neurodevelopmental disorder with high heterogeneity. Following our genome-wide associated loci with autism, we performed sequencing analysis of the coding regions, UTR and flanking splice junctions of AMPD1 in 830 Chinese autism individuals as well as 514 unrelated normal controls. Fourteen novel variants in the coding sequence were identified, including 11 missense variants and 3 synonymous mutations. Among these missense variants, 10 variants were absent in 514 control subjects, and conservative and functional prediction was carried out. Mitochondria activity and lactate dehydrogenase assay were performed in 5 patients' lymphoblast cell lines; p.P572S and p.S626C showed decreased mitochondrial complex I activity, and p.S626C increased lactate dehydrogenase release in medium. Conclusively, our data suggested that mutational variants in AMPD1 contribute to autism risk in Han Chinese population, uncovering the contribution of mutant protein to disease development that operates via mitochondria dysfunction and cell necrosis.

Metabolic and mitochondrial disorders associated with epilepsy in children with autism spectrum disorder

Autism spectrum disorder (ASD) affects a significant number of individuals in the United States, with the prevalence continuing to grow. A significant proportion of individuals with ASD have comorbid medical conditions such as epilepsy. In fact, treatment-resistant epilepsy appears to have a higher prevalence in children with ASD than in children without ASD, suggesting that current antiepileptic treatments may be suboptimal in controlling seizures in many individuals with ASD. Many individuals with ASD also appear to have underlying metabolic conditions. Metabolic conditions such as mitochondrial disease and dysfunction and abnormalities in cerebral folate metabolism may affect a substantial number of children with ASD, while other metabolic conditions that have been associated with ASD such as disorders of creatine, cholesterol, pyridoxine, biotin, carnitine, γ-aminobutyric acid, purine, pyrimidine, and amino acid metabolism and urea cycle disorders have also been associated with ASD without the prevalence clearly known. Interestingly, all of these metabolic conditions have been associated with epilepsy in children with ASD. The identification and treatment of these disorders could improve the underlying metabolic derangements and potentially improve behavior and seizure frequency and/or severity in these individuals. This paper provides an overview of these metabolic disorders in the context of ASD and discusses their characteristics, diagnostic testing, and treatment with concentration on mitochondrial disorders. To this end, this paper aims to help optimize the diagnosis and treatment of children with ASD and epilepsy. This article is part of a Special Issue entitled "Autism and Epilepsy".

Mechanism of nitrogen metabolism-related parameters and enzyme activities in the pathophysiology of autism

BACKGROUND

There is evidence that impaired metabolism play an important role in the etiology of many neuropsychiatric disorders. Although this has not been investigated to date, several recent studies proposed that nitrogen metabolism-related parameters may have a pathophysiological role in autism.

METHODS

The study enrolled 20 Saudi boys with autism aged 4 to 12 years and 20 healthy controls matched for age and gender. Levels of creatine, urea, ammonia, gamma-aminobutyric acid (GABA), glutamate:glutamine (Glu:Gln) ratio, and enzymatic activities of glutamate dehydrogenase, 5'-nucleotidase, and adenosine deaminase (ADA) were determined in plasma samples from both groups.

RESULTS

We found a significant elevation of creatine, 5'-nucleotidase, GABA, and glutamic acid and a significant decrease in the enzymatic activity of ADA and glutamine level in patients with autism compared with healthy controls. The most significant variation between the two groups was found in the Glu:Gln ratio.

CONCLUSION

A raised Glu:Gln ratio together with positive correlations in creatine, GABA, and 5'-nucleotidase levels could contribute to the pathophysiology of autism, and might be useful diagnostic markers. The mechanism through which these parameters might be related to autism is discussed in detail.

Noninvasive urinary organic acids test to assess biochemical and nutritional individuality in autistic children

OBJECTIVES

Quantitative organic acid testing can give information about potential problems, especially with energy production, neurotransmitter metabolism, intestinal dysbiosis and nutritional individuality which is very important in autistic children. The aim of this study was to find out potential differences between the levels of organic acids in the urine of autistic and non-autistic children.

DESIGN AND METHODS

The organic acids in the urine were determined by capillary gas chromatography/mass spectrometry (GC/MS). All overnight urine samples were collected from 35 autistic children and 36 neurologically normal children as healthy controls (4-10 years).

RESULTS

Significant differences were found between the autistic children and the control group in organic acids: 2-oxoglutaric, isocitric, citric, 4-hydroxybenzoic, 4-hydroxyphenylacetic, hippuric, adipic, suberic (all with p<0.05).

CONCLUSION

Organic acids test can be used to assess an individual need for nutrient and biochemical abnormalities, especially important for autistic children.

Pediatric neurological syndromes and inborn errors of purine metabolism

This review is devised to gather the presently known inborn errors of purine metabolism that manifest neurological pediatric syndromes. The aim is to draw a comprehensive picture of these rare diseases, characterized by unexpected and often devastating neurological symptoms. Although investigated for many years, most purine metabolism disorders associated to psychomotor dysfunctions still hide the molecular link between the metabolic derangement and the neurological manifestations. This basically indicates that many of the actual functions of nucleosides and nucleotides in the development and function of several organs, in particular central nervous system, are still unknown. Both superactivity and deficiency of phosphoribosylpyrophosphate synthetase cause hereditary disorders characterized, in most cases, by neurological impairments. The deficiency of adenylosuccinate lyase and 5-amino-4-imidazolecarboxamide ribotide transformylase/IMP cyclohydrolase, both belonging to the de novo purine synthesis pathway, is also associated to severe neurological manifestations. Among catabolic enzymes, hyperactivity of ectosolic 5'-nucleotidase, as well as deficiency of purine nucleoside phosphorylase and adenosine deaminase also lead to syndromes affecting the central nervous system. The most severe pathologies are associated to the deficiency of the salvage pathway enzymes hypoxanthine-guanine phosphoribosyltransferase and deoxyguanosine kinase: the former due to an unexplained adverse effect exerted on the development and/or differentiation of dopaminergic neurons, the latter due to a clear impairment of mitochondrial functions. The assessment of hypo- or hyperuricemic conditions is suggestive of purine enzyme dysfunctions, but most disorders of purine metabolism may escape the clinical investigation because they are not associated to these metabolic derangements. This review may represent a starting point stimulating both scientists and physicians involved in the study of neurological dysfunctions caused by inborn errors of purine metabolism with the aim to find novel therapeutical approaches.

Genotype and natural history in unrelated individuals with phenylketonuria and autistic behavior

We describe three unrelated individuals, two males (ages 35 and 9) and a female (age 8) presenting with late diagnosed phenylketonuria (PKU) and autistic behavior, all showing poor adhesion to the dietary treatment resulting in high plasmatic phenylalanine levels, particularly in the oldest subject. Clinical findings included hair hypopigmentation, microcephaly, severe mental retardation with absent development of verbal language and autistic symptoms in all three patients, whereas variable neurological signs such as seizures, spasticity, ataxia, aggressivity, and hyperactivity were individually found. Homozygosity for the IVS10nt11g/a (IVS10nt546) was found in all. This is the first report of molecular findings in subjects with PKU also presenting with autistic features. The authors discuss if this mutation is particularly involved in the association of autistic symptoms in untreated PKU individuals.

[Substitutive and dietetic approaches in childhood autistic disorder: interests and limits]

INTRODUCTION

Autism is a developmental disorder that requires specialized therapeutic approaches. Influenced by various theoretical hypotheses, therapeutic programs are typically structured on a psychodynamic, biological or educative basis. Presently, educational strategies are recommended in the treatment of autism, without excluding other approaches when they are necessary. Some authors recommend dietetic or complementary approaches to the treatment of autism, which often stimulates great interest in the parents but also provokes controversy for professionals. Nevertheless, professionals must be informed about this approach because parents are actively in demand of it.

LITERATURE FINDINGS

First of all, enzymatic disorders and metabolic errors are those most frequently evoked in the literature. The well-known phenylalanine hydroxylase deficit responsible for phenylketonuria has been described as being associated with autism. In this case, adapted diet prevents mental retardation and autistic symptoms. Some enzymatic errors are also corrected by supplementation with uridine or ribose for example, but these supplementations are the responsibility of specialized medical teams in the domain of neurology and cannot be applied by parents alone. Secondly, increased opoid activity due to an excess of peptides is also supposed to be at the origin of some autistic symptoms. Gluten-free or casein-free diets have thus been tested in controlled studies, with contradictory results. With such diets, some studies show symptom regression but others report negative side effects, essentially protein malnutrition. Methodological bias, small sample sizes, the use of various diagnostic criteria or heterogeneity of evaluation interfere with data analysis and interpretation, which prompted professionals to be cautious with such diets. The third hypothesis emphasized in the literature is the amino acid domain. Some autistic children lack some amino acids such as glutamic or aspartic acids for example and this deficiency would create autistic symptoms. However, for some authors, these deficits are attributed to nutritional deficits caused by the food selectivity of children. A fourth hypothesis concerning metabolic implication in autism is the suspicion that a food allergy phenomenon could interfere with development, and it has been observed that Ig levels are higher in autistic children than in control children. Autistic children with a positive reaction to food Ig would have a more favourable outcome with diet excluding some kinds of food; but most of those diets are drastic and ethically debatable. Fifth, glucidic catabolism could be deleterious with an excess of ketonic products that will initiate comitial seizures. Few studies with ketogenic diet have been conducted but, as it has been described with epileptic subjects, those diets would diminish autistic symptoms. Not enough studies have been conducted that would allow one to draw any firm conclusions. The sixth hypothesis is linked with vitamin deficiencies that are a notably important area of research in the treatment of autism. Vitamin B12 or B6 deficiencies have been studied in several articles, and many of them were controlled studies. French teams also emphasize an interest in supplementation with B12 or B6. The two last hypotheses concern auto-immune patterns and the toxic effects of heavy metals like mercury. There is a paucity of methodologically satisfying studies that support these two hypotheses and diet recommendations. Following these assumptions, some dietetic approaches have been recommended, even though the methodological aspects of supporting studies are poor. The most famous diet is the gluten-free and/or casein-free diet. Only two controlled studies attracted our attention. Even if for some autistic children such a diet was positive, for others, gluten-free or casein-free diets were poorly tolerated and, for some authors, not without considerable side effects, the more prejudicial of which was the Kwashiorkor risk. Ketogenic diets have been studied in one non controlled study, but even if positive results have been noted by the authors, the ketogenic diet is very restricting and the long term effects have not been evaluated. Vitamin supplementation is the one and only diet domain where there have been many repeated and placebo-controlled studies. Side effects are rare and mild even if high doses of vitamin B6 are advocated in these studies. In total, as evoked by Rimland, 11 controlled placebo-blind studies have been conducted and 50% of autistic children with this supplementation had improved autistic signs. However, these results still remain debated. Finally, more rarely, enzymatic abnormalities need specific diets which have some positive consequences, but such diets could not be applied by parents alone and are the responsibility of specialized teams. For discussion purposes we can emphasize that, in spite of the amount of studies concerning the effects of specialized diets, few are methodologically satisfying. We can not ignore that some side effects are possible with such approaches and parents need to be informed of them. Some are even potentially serious, such as diets with metal chelators. In spite of those results, vitamin supplementation seems to be the only one that some specialized teams in autism could apply, always with parent agreement. In conclusion, within this scientific field, studies on eating habits of autistic children should be conducted because of their food selectivity or avoidance.

Autism and metabolic diseases

Autism is an etiologic heterogeneous entity caused by many different diseases occurring in the central nervous system at an early stage in life. Several metabolic defects have been associated with autistic symptoms with a rate higher than that found in the general population. Inborn errors of metabolism can probably account for less than 5% of individuals. Selective metabolic testing should be done in the presence of suggestive clinical findings, including lethargy, cyclic vomiting, early seizures, dysmorphic features, and mental retardation. In some patients, early diagnosis of the metabolic disorders and proper therapeutic interventions may significantly improve the long-term cognitive and behavioral outcome.

Childhood autism and associated comorbidities

Autism is a heterogeneous neurodevelopmental disorder with a variety of different etiologies, but with a heritability estimate of more than 90%. Although the strong correlation between autism and genetic factors has been long established, the exact genetic background of autism is still unclear. This review refers to all the genetic syndromes that have been described in children with pervasive developmental disorders (tuberous sclerosis, fragile X, Down, neurofibromatosis, Angelman, Prader-Willi, Gilles de la Tourette, Williams, etc.). Issues covered include prevalence and main characteristics of each syndrome, as well as the possible base of its association with autism in terms of contribution to the current knowledge on the etiology and genetic base of pervasive developmental disorders.

Coping strategies used by parents of children with autism

PURPOSE

The purpose of this research was to determine (a) the level of family adaptation, as measured by the Family Crisis Oriented Personal Evaluation Scales (F-COPESs) instrument, among persons with a child diagnosed with autism spectrum disorder (ASD) aged 12 years and under, (b) if there was a difference in F-COPES scores based on family demographics, and (c) the time lag between parent's suspicion of ASD and the actual professional diagnosis of ASD.

DATA SOURCES

A descriptive survey was used with a convenience sample derived from ASD treatment agencies and a parental support group in the California Bay Area that supports the children and parents of children with special needs.

CONCLUSIONS

Overall, the level of adaptation was within the normal limits with coping scores similar to the norm scores of the F-COPES with males scoring slightly higher than females in the coping scale. Subscale scores of the F-COPES indicated that the parents sought encouragement and support from friends, informal support from other families who faced similar problems, and formal support from agencies and programs. Reframing revealed similar results as the norm with less use of spiritual support, and more passive appraisals were noted from the parents of children with ASD. Within internal comparisons, there were no statistical differences among gender and amount of time a member spent in coordination of services. Comparisons in ethnicity for Caucasians and Asian Americans revealed a higher coping score for reframing in Asian Americans and a higher passive appraisal score among Caucasians. Non-English speakers scored higher on spiritual support, while English speakers scored higher in passive appraisals. Because of insufficient statistical power, comparisons in education, income, marital status, and relocation of residence were deferred. The time from parents' suspicions of developmental delays or disability to a professional diagnosis of ASD was at least 6 months or greater.

IMPLICATIONS FOR PRACTICE

It is imperative for nurse practitioners (NPs) to provide appropriate professional support and other social support systems to families with children with ASD. Educating parents to sound therapy approaches to provide them with the skills needed to directly address stressful events in order to increase the parent's confidence level as to avoid passive appraisals is also a crucial role of the NP. NPs may want to use the F-COPES as part of the assessment to ascertain the areas of needs of families. This study reveals the resiliency and highly adaptive nature of these parents who are under severe strain and stress of caring for a child with ASD. The effective ways they coped as a family were in the areas of informal and formal social support networks. Participants also used passive appraisal to cope. The study also supports the need for early recognition and diagnoses of ASD and referral for early intervention for better outcomes for the children and families affected by ASD.

Complementary and alternative medicine in developmental disabilities

Developmental disabilities (DD) are defined as a diverse group of severe chronic conditions due to mental and/or physical impairments. Individuals with developmental disabilities have difficulty with major life activities including language, mobility, and learning. Developmental disabilities can begin anytime during development--from prenatal up to 22 years of age, and the disability usually lasts throughout a person's lifetime. Autism spectrum disorders, cerebral palsy, mental retardation, and attention deficit hyperactivity disorder are common conditions falling within the definition of developmental disabilities. Complementary and alternative medicine (CAM) is becoming increasingly utilized in the general population for treatment of everything from the common cold to complex and chronic medical conditions. This article reviews the prevalence of different types of CAM used for various developmental disabilities.

Autismus und Stoffwechselerkrankungen - was ist gesichert?

Zusammenfassung: Die Ursachen für Autismus sind heterogen und ganz überwiegend genetischer Natur. Eine exakte benennbare Ätiologie wird in weniger als 10% der Fälle gefunden. Die Enttäuschung über den geringen Erfolg bei der Ursachenfindung und zahlreiche Berichte über die Assoziation von Autismus mit Stoffwechselerkrankungen sowie über «Wunderheilungen» bei unterschiedlichsten medikamentösen oder diätetischen Therapien haben bei vielen Ärzten und Eltern zu einer zunehmenden Unsicherheit über die sinnvolle Diagnostik und Behandlung geführt. Diese Arbeit gibt einen Überblick über seltene angeborene Stoffwechselerkrankungen («inborn errors of metabolism»), die nachweislich (z.B. Phenylketonurie, Smith-Lemli-Opitz Syndrom) oder wahrscheinlich (z.B. Succinat-Semialdehyd-Dehydrogenase-Mangel) mit Autismus-spezifischen Symptomen vergesellschaftet sind. In aller Regel weisen betroffene Patienten zusätzliche neurologische Symptome auf. Es werden die zur Diagnostik dieser angeborenen Stoffwechselerkrankungen notwendigen Untersuchungen und mögliche therapeutische Maßnahmen dargestellt. Neben diesen gut definierten Stoffwechselerkrankungen mit der Möglichkeit einer rationalen Therapie wird auch auf Hypothesen über die Entstehung von Autismus durch «Stoffwechselveränderungen» eingegangen, die entweder nicht bewiesen oder nachweislich falsch sind.

Metabolic biomarkers of increased oxidative stress and impaired methylation capacity in children with autism

BACKGROUND

Autism is a complex neurodevelopmental disorder that usually presents in early childhood and that is thought to be influenced by genetic and environmental factors. Although abnormal metabolism of methionine and homocysteine has been associated with other neurologic diseases, these pathways have not been evaluated in persons with autism.

OBJECTIVE

The purpose of this study was to evaluate plasma concentrations of metabolites in the methionine transmethylation and transsulfuration pathways in children diagnosed with autism.

DESIGN

Plasma concentrations of methionine, S-adenosylmethionine (SAM), S-adenosylhomocysteine (SAH), adenosine, homocysteine, cystathionine, cysteine, and oxidized and reduced glutathione were measured in 20 children with autism and in 33 control children. On the basis of the abnormal metabolic profile, a targeted nutritional intervention trial with folinic acid, betaine, and methylcobalamin was initiated in a subset of the autistic children.

RESULTS

Relative to the control children, the children with autism had significantly lower baseline plasma concentrations of methionine, SAM, homocysteine, cystathionine, cysteine, and total glutathione and significantly higher concentrations of SAH, adenosine, and oxidized glutathione. This metabolic profile is consistent with impaired capacity for methylation (significantly lower ratio of SAM to SAH) and increased oxidative stress (significantly lower redox ratio of reduced glutathione to oxidized glutathione) in children with autism. The intervention trial was effective in normalizing the metabolic imbalance in the autistic children.

CONCLUSIONS

An increased vulnerability to oxidative stress and a decreased capacity for methylation may contribute to the development and clinical manifestation of autism.

Autism spectrum disorder: screening, diagnosis, and medical evaluation

Autism spectrum disorder (ASD) are a group of behaviorally defined neurodevelopmental disabilities with core deficits in socialization, communication, and behavior, although the presentation can be extremely variable. This article describes the core deficits in ASD, as well as the differential diagnosis and the more commonly associated comorbid disorders. The importance of early diagnosis is emphasized, and screening and assessment tools are reviewed. Finally, the role of the pediatric neurologist is discussed with regard to specific components of the evaluation, including history, physical examination, and ancillary testing.

Childhood autism: a circuit syndrome?

BACKGROUND

Autism is a disorder that can lead to life-long disability. Currently, the etiology of autism is unknown, and although there are treatments for some of the behavioral abnormalities, there is no cure.

REVIEW SUMMARY

While this article will review the clinical, anatomic, and pathologic features seen in autism, the primary focus will be to present a new and provocative unifying theory regarding the underlying mechanisms causing this disorder. Current research advances, some controversial, will be discussed, and a novel definition of autism as a "circuit syndrome" will be presented. The work elaborated here will tie many of the disparate findings together, based on the idea that autism arises from abnormalities of the cerebellolimbic circuitry. Some of the more alternative theories of autism, such as mercury toxicity, linkage to the measles, mumps, and rubella vaccine, and the use of secretin will be discussed. Finally, pharmacologic treatment options will be reviewed.

CONCLUSIONS

Autism is not single disorder but represents dysfunction of the cerebellolimbic circuitry that can arise from many different etiologies.

Metabolic treatment of hyperuricosuric autism

A single male subject with hyperuricosuric autism was treated for a period of 2 years with an oral dose of uridine, which increased from 50 to 500 mg/kg/day. This patient experienced dramatic social, cognitive, language, and motor improvements. These improvement decreased within 72 h of the discontinuation of uridine, but reappeared when uridine supplementation was resumed. Thus, it appears that patients with hyperuricosuric autism benefit from metabolic therapy with oral uridine therapy in a manner similar to that seen in other disorders of purine metabolism in which there is autistic symptomatology.