Multi-frequency localization of aberrant brain activity in autism spectrum disorder.

OBJECTIVE: The abnormality of intrinsic brain activity in autism spectrum disorders (ASDs) is still inconclusive. Contradictory results have been found pointing towards hyper-activity or hypo-activity in various brain regions. The present research aims to investigate the spatial and spectral signatures of aberrant brain activity in an unprecedented frequency range of 1-2884 Hz at source levels in ASD using newly developed methods. MATERIALS AND METHODS: Seven ASD subjects and age- and gender-matched controls were studied using a high-sampling rate magnetoencephalography (MEG) system. Brain activity in delta (1-4 Hz), theta (4-8 Hz), alpha (8-12 Hz), beta (12-30 Hz), low gamma (30-55 Hz), high gamma (65-90 Hz), ripples (90-200 Hz), high-frequency oscillations (HFOs, 200-1000 Hz), and very high-frequency oscillations (VHFOs, 1000-2884 Hz) was volumetrically localized and measured using wavelet and beamforming. RESULTS: In comparison to controls, ASD subjects had significantly higher odds of alpha activity (8-12 Hz) in the sensorimotor cortex (mu rhythm), and generally high-frequency activity (90-2884 Hz) in the frontal cortex. The source power of HFOs (200-1000 Hz) in the frontal cortex in ASD was significantly elevated as compared with controls. CONCLUSION: The results suggest that ASD has significantly altered intrinsic brain activity in both low- and high-frequency ranges. Increased intrinsic high-frequency activity in the frontal cortex may play a key role in ASD.

Classification of children with autism spectrum disorder by sensory subtype: a case for sensory-based phenotypes.

This study examines whether sensory differences can be used to classify meaningful subgroups of children with autism spectrum disorder (ASD). Caregivers of children with ASD aged 2-10 years (n = 228) completed the Short Sensory Profile. Model-based cluster analysis was used to extract sensory subtypes. The relationship of these subtypes to age, gender, autism symptom severity, and nonverbal intelligence quotient (IQ) was further explored. Four distinct sensory subtypes were identified: (a) sensory adaptive; (b) taste smell sensitive; (c) postural inattentive; and (d) generalized sensory difference. The sensory subtypes differ from each other on two dimensions: (a) the severity of reported sensory differences; and (b) the focus of differences across auditory, taste, smell, vestibular and proprioceptive domains. Examination of the clinical features of each subtype reveals two possible mechanisms of sensory disturbance in autism: (a) sensory hyperreactivity; and (b) difficulties with multisensory processing. Further, the sensory subtypes are not well explained by other variables such as age, gender, IQ, and autism symptom severity. We conclude that classification of children using sensory differences offers a promising method by which to identify phenotypes in ASD. Sensory-based phenotypes may be useful in identifying behavioral features responsive to specific interventions thereby improving intervention effectiveness. Further validation of the sensory-based phenotypes by establishing neural and physiological correlates is recommended.

Iron status in children with autism spectrum disorder.

BACKGROUND AND OBJECTIVES: Children with autism spectrum disorders (ASDs) often have food selectivity and restricted diets, putting them at risk for nutritional deficiencies. Previous studies have demonstrated a high prevalence of iron deficiency (ID) in children with ASDs living in Wales, Canada, and Turkey. The objectives of this study were to determine the prevalence of ID and the adequacy of iron intake in children with ASD in the United States. METHODS: Participants (age 2-11 years recruited from the Autism Treatment Network Diet and Nutrition Study) completed a 3-day diet record (n = 368) and had laboratory measures of serum ferritin (SF), complete blood count, iron, total iron binding capacity, and transferrin saturation (TS) (n = 222). RESULTS: Of the 222 participants with laboratory data, 18 (8%) had SF <12 µg/L and 2 (1%) had ID defined by both low SF and TS (3 children with low SF had missing TS data). One subject had iron deficiency anemia. Fewer than 2% of subjects had iron intake below the estimated average requirement. CONCLUSIONS: Although the determination of iron status is complex, these data do not support previous reports that children with ASD are at greater risk for ID than the general population; however, 8% percent of the sample did demonstrate low SF despite <2% of the sample demonstrating iron intake below the estimated average requirement. The prevalence of low SF may be an underestimate, because SF is an acute phase reactant and the study included no measure of inflammation.

Nutrient intake from food in children with autism.

OBJECTIVE: The impact of abnormal feeding behaviors reported for children with autism spectrum disorders (ASDs) on their nutritional status is unknown. We compared nutrient intake from food consumed by children with and without ASD and examined nutrient deficiency and excess. METHODS: Prospective 3-day food records and BMI for children (2-11 years) with ASD participating in the Autism Treatment Network (Arkansas, Cincinnati, Colorado, Pittsburgh, and Rochester) were compared with both the National Health and Nutrition Examination Survey data and a matched subset based on age, gender, family income, and race/ethnicity (N = 252 analyzed food records). RESULTS: Children with ASD and matched controls consumed similar amounts of nutrients from food. Only children with ASD aged 4 to 8 years consumed significantly less energy, vitamins A and C, and the mineral Zn; and those 9 to 11 years consumed less phosphorous. A greater percentage of children with ASD met recommendations for vitamins K and E. Few children in either group met the recommended intakes for fiber, choline, calcium, vitamin D, vitamin K, and potassium. Specific age groups consumed excessive amounts of sodium, folate, manganese, zinc, vitamin A (retinol), selenium, and copper. No differences were observed in nutritional sufficiency of children given restricted diets. Children aged 2 to 5 years with ASD had more overweight and obesity, and children 5 to 11 years had more underweight. CONCLUSIONS: Children with ASD, like other children in America, consume less than the recommended amounts of certain nutrients from food. Primary care for all children should include nutritional surveillance and attention to BMI.

Use of the Autism Diagnostic Observation Schedule (ADOS) in a clinical setting.

The aim of this study was to examine the Autism Diagnostic Observation Schedule (ADOS) as it is commonly used in clinical practice. ADOS classifications were compared to final diagnoses given by a multidisciplinary team to 584 children referred for evaluation for possible autism spectrum disorder (ASD) at the Cincinnati Children's Hospital Medical Center. A total of 177 children were evaluated with a Module 1 (87 No Words), 198 with a Module 2 (90 < 5 years) and 209 with a Module 3. Of these, 142 (26%) were diagnosed with autism, 185 (32%) with non-autism ASD, and 257 (44%) with non-spectrum disorders. Sensitivities were moderate to high on both original and revised algorithms, while specificities were substantially lower than those previously reported. This difference is likely attributable to the composition of the sample that included many children with a broad array of developmental and behavioral disorders. The clinical impression of the team member who administered the ADOS was critical to the accuracy of the overall diagnosis. Using numeric scores alone resulted in misclassification from false positive results. The study highlights the importance of the qualitative interactions of the ADOS activities as well as the score in diagnostic decision making.

Finger bone immaturity and 2D:4D ratio measurement error in the assessment of the hyperandrogenic hypothesis for the etiology of autism spectrum disorders.

Emerging hypotheses suggest a causal role for prenatal androgen exposure in some cases of autism spectrum disorders (ASD). The ratios of the lengths of the bones of the 2nd to the 4th digit (2D:4D) are purported to be markers for prenatal androgen exposure and to be established early in gestation. Elongation of the 4th digit in response to testosterone is said to reduce 2D:4D in males versus females. We examined the ratios of bones from the left hand radiographs of 75 boys and 6 girls 4-8 years of age, diagnosed with ASD, to evaluate digit ratio as a marker for gestational androgen exposure. Contrary to our expectations, girls had reduced 2D:4D compared to boys but the difference was not significant (Cohen's D 0.51-0.66, P>0.05). The limited sample size for this study and the absence of a referent group precluded providing robust estimates for girls and identifying possible statistical differences between the sexes. Tanner-Whitehouse 3 (TW3) rating of finger bone growth suggested relative immaturity of the 4th relative to the 2nd digits. Positive correlations were detected for 2D:4D ratios, body mass index (r=0.23, P=0.039), chronologic age (r=0.35, P=0.001), and skeletal age (r=0.42, P<0.0001). The TW3 ratings and associations between 2D:4D ratios and indicators of growth suggest that digits develop at different rates. This asynchronous development may produce differences in 2D:4D over time which could lead to erroneous interpretation of androgen exposure in utero among young ASD children.

Acute haematogenous infection of a closed vertebral fracture.

Acute haematogenous infection of a closed fractures is rare. A 68-year-old diabetic male sustained a burst fracture of a lumbar vertebra (L2) after a fall onto his back. After 5 days of conservative management, he developed a chest infection and amoxicillin was commenced empirically. However, after 6 days his previously moderate focal L2 back pain had become more severe. Pyrexia and systemic inflammatory markers continued to rise despite administration of antibiotics. Blood cultures and a CT-guided biopsy of L2 both revealed Staphylococcus aureus which was sensitive to flucloxacillin. The patient's symptoms and signs gradually normalised following administration of flucloxacillin for 6 weeks, and the use of a cast brace. We conclude that haematogenous infection can be successfully managed non-operatively.

Parent and teacher report of social skills in children with autism spectrum disorders.

PURPOSE: The purpose of this study was to examine the agreement between parent and teacher perceptions of specific social behaviors in children with autism spectrum disorders (ASD). METHOD: Informant ratings were generated concerning 45 children with ASD between the ages of 5 and 14 years who were enrolled in social skills groups at 2 Midwestern outpatient autism treatment centers. RESULTS: Moderate agreement was observed between parents and teachers for the overall social skills rating scores (r = 0.34; p < 0.05), but there was little agreement on specific social items. Distinct patterns of skill profiles emerged. Parents consistently provided relatively higher ratings on items that pertained to initiating interactions. Teachers, on the other hand, consistently provided higher ratings on items related to responding to and maintaining interactions. Parents and teachers agreed most often on items of affective understanding and perspective taking. CONCLUSION: These findings suggest that specific social behaviors may be context dependent, indicating the need for a multi-informant approach to provide a more complete profile of a child's social abilities, which is necessary for generating a more effective treatment plan.

Difference in age at regression in children with autism with and without Down syndrome.

OBJECTIVE: Autism occurs more frequently in individuals with Down syndrome than it does in the general population. Among children with autism and Down syndrome, regression is reported to occur in up to 50%. The aim of this study was to characterize and compare regression in children with autism with and without Down syndrome. METHODS: In this case-control study, children with Down syndrome and autism characterized by a history of developmental regression (n = 12) were compared to children with autism with regression who did not have Down syndrome, matched for chronologic age and gender. Comparisons were made on age at acquisition of language and age at loss of language and other skills as measured by the Autism Diagnostic Interview-Revised (ADI-R). RESULTS: The mean age at acquisition of meaningful use of single words was 40.6 months (SD = 38.0) in children with Down syndrome and autism compared to 14.9 months (SD = 8.5) in children with autism without Down syndrome (p = .005). The mean age at language loss in children with autism with Down syndrome was 61.8 months (SD = 22.9) compared to 19.7 months (SD = 5.8) for those with autism without Down syndrome (p = .01). The mean age at other skill loss was 46.2 months (SD = 19.1) and 19.5 months (SD = 5.6), respectively (p = .006). CONCLUSIONS: When regression occurs in children with autism and Down syndrome it is, on average, much later than is typically seen in children with autism without Down syndrome.

Reduced bone cortical thickness in boys with autism or autism spectrum disorder.

Bone development, casein-free diet use, supplements, and medications were assessed for 75 boys with autism or autism spectrum disorder, ages 4-8 years. Second metacarpal bone cortical thickness (BCT), measured on hand-wrist radiographs, and % deviations in BCT from reference medians were derived. BCT increased with age, but % deviations evidenced a progressive fall-off (p = .02): +3.1 +/- 4.7%, -6.5 +/- 4.0%, -16.6 +/- 3.4%, -19.4 +/- 3.7%,-24.1 +/- 4.4%, at ages 4-8, respectively, adjusting for height. The 12% of the boys on casein-free diets had an overall % deviation of -18.9 +/- 3.7%, nearly twice that of boys on minimally restricted or unrestricted diets (-10.5 +/- 1.3%, p < .04), although even for boys on minimally restricted or unrestricted diets the % deviation was highly significant (p < .001). Our data suggest that the bone development of autistic boys should be monitored as part of routine care, especially if they are on casein-free diets.

Elevated levels of growth-related hormones in autism and autism spectrum disorder.

OBJECTIVE: Children with autism are known to have larger head circumferences; whether they are above average in height and weight is less clear. Moreover, little is known about growth-related hormone levels in children with autism. We investigated whether children with autism were taller and heavier, and whether they had higher levels of growth-related hormones than control children did. DESIGN: A case-control study design was employed. PATIENTS: Boys with autism spectrum disorder (ASD) or autism (n = 71) and age-matched control boys (n = 59) were evaluated at Cincinnati Children's Hospital. MEASUREMENTS: Height, weight and head circumference were measured. Blood samples were assayed for IGF-1 and 2, IGFBP-3, growth hormone binding protein (GHBP) and for dehydroepiandrosterone (DHEA) and DHEA sulphate (DHEAS). RESULTS: Subjects with autism/ASD had significantly (P = 0.03) greater head circumferences (mean z-score 1.24, SD 1.35) than controls (mean z-score 0.78, SD 0.93). Subjects with autism also had significantly (P = 0.01) greater weights (mean z-score 0.91, SD 1.13) than controls (mean z-score 0.41, SD 1.11). Height did not differ significantly between groups (P = 0.65); subjects with autism/ASD had significantly (P = 0.003) higher body mass indices (BMI) (mean z-score 0.85, SD 1.19) than controls (mean z-score 0.24, SD 1.17). Levels of IGF-1, IGF-2, IGFBP-3 and GHBP in the group with autism/ASD were all significantly higher (all P < or = 0.0001) than in controls. CONCLUSIONS: Children with autism/ASD had significantly higher levels of many growth-related hormones: IGF-1, IGF-2, IGFBP-3 and GHBP. These findings could help explain the significantly larger head circumferences and higher weights and BMIs seen in these subjects. Future studies should examine the potential role of growth-related hormones in the pathophysiology of autism.

Familial autoimmune thyroid disease as a risk factor for regression in children with Autism Spectrum Disorder: a CPEA Study.

A multicenter study of 308 children with Autism Spectrum Disorder (ASD) was conducted through the Collaborative Programs of Excellence in Autism (CPEA), sponsored by the National Institute of Child Health and Human Development, to compare the family history of autoimmune disorders in children with ASD with and without a history of regression. A history of regression was determined from the results of the Autism Diagnostic Interview-Revised (ADI-R). Family history of autoimmune disorders was obtained by telephone interview. Regression was significantly associated with a family history of autoimmune disorders (adjusted OR=1.89; 95% CI: 1.17, 3.10). The only specific autoimmune disorder found to be associated with regression was autoimmune thyroid disease (adjusted OR=2.09; 95% CI: 1.28, 3.41).

Elevated cytokine levels in children with autism spectrum disorder.

UNLABELLED: This study compared production of IL-2, IFN-gamma, IL-4, IL-13, IL-5 and IL-10 in peripheral blood mononuclear cells from 20 children with autism spectrum disorder to those from matched controls. Levels of all Th2 cytokines were significantly higher in cases after incubation in media alone, but the IFN-gamma/IL-13 ratio was not significantly different between cases and controls. Cases had significantly higher IL-13/IL-10 and IFN-gamma/IL-10 than controls. CONCLUSION: Children with ASD had increased activation of both Th2 and Th1 arms of the adaptive immune response, with a Th2 predominance, and without the compensatory increase in the regulatory cytokine IL-10.

Electroencephalogram abnormalities in children with autism spectrum disorders.

Children with an autism spectrum disorder (ASD) often are evaluated with electroencephalogram (EEG) studies to assess their risk for seizures or other underlying abnormalities. Their risk is estimated at 7% - 42%. EEG studies were conducted on a subgroup of children while following established practice parameters for evaluating children for ASD. Abnormal EEG results were obtained in 85 (27%) of the 316 children evaluatedfor ASD. Within the subset of abnormal results, 64 children had autism, 10 had an ASD or milder presentation, 6 had another developmental disorder, 3 had Rett syndrome, had Down syndrome, and 1 had Wolf-Hirshhorn syndrome. The abnormal EEG findings included epileptiform abnormalities in 55 patients (65%), and slowing in only 13 patients (15%). The focality of the epileptiformfindings included 26 (30%) in the temporal areas, 24 (28%) in the central area, 20 (23%) in the frontal area, and 7 (8%) in the occipital area. These findings confirm the importance of ongoing medicalfollow-up for children with ASDs, especially for those with abnormal EEG results.

Prevalence of chronic gastrointestinal symptoms in children with autism and autistic spectrum disorders.

The purpose of this study was to estimate the prevalence of chronic gastrointestinal symptoms in a general population of children with autism or autistic spectrum disorder (ASD). The study site was a clinic specializing in ASD in a large pediatric medical center serving a 10 county area in the midwestern USA. In a sample of 137 children, age 24-96 months, classified as having autism or ASD by the Autism Diagnostic Observation Schedule-Generic, 24 percent had a history of at least one chronic gastrointestinal symptom. The most common symptom was diarrhea, which occurred in 17 percent. There was no association between chronic gastrointestinal symptoms and a history of developmental regression. The potential phenotypic association between autism and gastrointestinal symptoms is discussed.

Postural stability in children with autism spectrum disorder.

Maintaining upright posture is a complex process involving multiple afferent systems. The aim of this study was to measure the postural stability of children with Autism Spectrum Disorder (ASD) compared with children with typical neurodevelopment and to measure the relative contributions of the visual, somatosensory, and vestibular afferent systems in each group. Eight boys with ASD and eight age-, race-, and gender-matched controls participated in this study using force platform technology with customized software to measure postural sway under conditions designed to eliminate or modify visual and somatosensory input. Children with ASD had significantly larger sway areas under all test conditions in which afferent input was modified. These results are consistent with a deficit in the integration of visual, vestibular, and somatosensory input to maintain postural orientation.

Lack of benefit of intravenous synthetic human secretin in the treatment of autism.

The objective of this study was to determine if an intravenous infusion of synthetic human secretin improves language and behavioral symptoms in children with autism. Forty-two children with the diagnosis of autism were randomized to one of two groups in this double-blind cross-over trial. One group received 2 IU/kg of intravenous synthetic human secretin at the first visit, followed by an equal volume of intravenous saline placebo at week 6. The other group received treatments in the reverse order. All children were evaluated at weeks 1, 3, 6, 9, and 12 with standardized assessments of language, behavior, and autism symptomatology. There were no significant differences in the mean scores on any measure of language, behavior, or autism symptom severity after treatment with secretin compared to treatment with placebo. The results of this study do not support secretin as a treatment for autism.