Development of a Brief Parent-Report Screen for Common Gastrointestinal Disorders in Autism Spectrum Disorder

Gastrointestinal dysfunction in children with autism spectrum disorder (ASD) is common and associated with problem behaviors. This study describes the development of a brief, parent-report screen that relies minimally upon the child's ability to report or localize pain for identifying children with ASD at risk for one of three common gastrointestinal disorders (functional constipation, functional diarrhea, and gastroesophageal reflux disease). In a clinical sample of children with ASD, this 17-item screen identified children having one or more of these disorders with a sensitivity of 84%, specificity of 43%, and a positive predictive value of 67%. If found to be valid in an independent sample of children with ASD, the screen will be useful in both clinical practice and research.

Mitochondrial dysfunction in the gastrointestinal mucosa of children with autism: A blinded case-control study

Gastrointestinal (GI) symptoms are prevalent in autism spectrum disorder (ASD) but the pathophysiology is poorly understood. Imbalances in the enteric microbiome have been associated with ASD and can cause GI dysfunction potentially through disruption of mitochondrial function as microbiome metabolites modulate mitochondrial function and mitochondrial dysfunction is highly associated with GI symptoms. In this study, we compared mitochondrial function in rectal and cecum biopsies under the assumption that certain microbiome metabolites, such as butyrate and propionic acid, are more abundant in the cecum as compared to the rectum. Rectal and cecum mucosal biopsies were collected during elective diagnostic colonoscopy. Using a single-blind case-control design, complex I and IV and citrate synthase activities and complex I-V protein quantity from 10 children with ASD, 10 children with Crohn’s disease and 10 neurotypical children with nonspecific GI complaints were measured. The protein for all complexes, except complex II, in the cecum as compared to the rectum was significantly higher in ASD samples as compared to other groups. For both rectal and cecum biopsies, ASD samples demonstrated higher complex I activity, but not complex IV or citrate synthase activity, compared to other groups. Mitochondrial function in the gut mucosa from children with ASD was found to be significantly different than other groups who manifested similar GI symptomatology suggesting a unique pathophysiology for GI symptoms in children with ASD. Abnormalities localized to the cecum suggest a role for imbalances in the microbiome, potentially in the production of butyrate, in children with ASD.

Durability of sustained response shown in paediatric patients with chronic hepatitis C who were treated with interferon alfa-2b plus ribavirin

Long-term studies in adults indicate that sustained virologic response (SVR) after combination treatment for chronic hepatitis C (CHC) predicts long-term clearance. Although peginterferon plus ribavirin is now standard care for children with CHC, long-term follow-up studies are not yet available. This study evaluated durability of virologic response over 5 years in children previously treated with interferon alfa-2b plus ribavirin (IFN/R). Ninety-seven of 147 children with CHC, who were treated with IFN/R and completed the 6-month follow-up in two previous clinical trials, participated in this long-term follow-up study. All were assessed annually for up to 5 years; patients with SVR were assessed for durability of virologic response. Children with SVR (n = 56) and those with detectable hepatitis C virus (HCV) RNA 24-week post-treatment (n = 41) were followed for a median of 284 weeks. Overall, 70% (68/97) of patients completed the 5-year follow-up. One patient with genotype 1a CHC had SVR and relapsed at year 1 of follow-up with the same genotype. Kaplan-Meier estimate for sustained response at 5 years was 98% (95% CI: 95%, 100%). Six patients with low-positive HCV RNA levels (n = 4) or missing HCV RNA at the 24-week follow-up visit (n = 2) in the initial treatment studies had virologic response during this long-term follow-up study. Linear growth rate was impaired during treatment with rapid increases in the immediate 6 months post-treatment. Mean height percentile at the end of the 5-year follow-up was slightly less than the mean pretreatment height percentile. Five patients experienced serious adverse events; none related to study drug exposure. SVR after IFN/R predicts long-term clearance of HCV in paediatric patients; growth normalized in the majority of children during the long-term follow-up. Similar long-term results could be expected after peginterferon alfa-2b plus ribavirin treatment.

Evaluation, diagnosis, and treatment of gastrointestinal disorders in individuals with ASDs: a consensus report

Autism spectrum disorders (ASDs) are common and clinically heterogeneous neurodevelopmental disorders. Gastrointestinal disorders and associated symptoms are commonly reported in individuals with ASDs, but key issues such as the prevalence and best treatment of these conditions are incompletely understood. A central difficulty in recognizing and characterizing gastrointestinal dysfunction with ASDs is the communication difficulties experienced by many affected individuals. A multidisciplinary panel reviewed the medical literature with the aim of generating evidence-based recommendations for diagnostic evaluation and management of gastrointestinal problems in this patient population. The panel concluded that evidence-based recommendations are not yet available. The consensus expert opinion of the panel was that individuals with ASDs deserve the same thoroughness and standard of care in the diagnostic workup and treatment of gastrointestinal concerns as should occur for patients without ASDs. Care providers should be aware that problem behavior in patients with ASDs may be the primary or sole symptom of the underlying medical condition, including some gastrointestinal disorders. For these patients, integration of behavioral and medical care may be most beneficial. Priorities for future research are identified to advance our understanding and management of gastrointestinal disorders in persons with ASDs.

Mitochondrial disease in autism spectrum disorder patients: a cohort analysis

Background

Previous reports indicate an association between autism spectrum disorders (ASD) and disorders of mitochondrial oxidative phosphorylation. One study suggested that children with both diagnoses are clinically indistinguishable from children with idiopathic autism. There are, however, no detailed analyses of the clinical and laboratory findings in a large cohort of these children. Therefore, we undertook a comprehensive review of patients with ASD and a mitochondrial disorder.

Methodology/Principal Findings

We reviewed medical records of 25 patients with a primary diagnosis of ASD by DSM-IV-TR criteria, later determined to have enzyme- or mutation-defined mitochondrial electron transport chain (ETC) dysfunction. Twenty-four of 25 patients had one or more major clinical abnormalities uncommon in idiopathic autism. Twenty-one patients had histories of significant non-neurological medical problems. Nineteen patients exhibited constitutional symptoms, especially excessive fatigability. Fifteen patients had abnormal neurological findings. Unusual developmental phenotypes included marked delay in early gross motor milestones (32%) and unusual patterns of regression (40%). Levels of blood lactate, plasma alanine, and serum ALT and/or AST were increased at least once in 76%, 36%, and 52% of patients, respectively. The most common ETC disorders were deficiencies of complex I (64%) and complex III (20%). Two patients had rare mtDNA mutations of likely pathogenicity.

Conclusions/Significance

Although all patients' initial diagnosis was idiopathic autism, careful clinical and biochemical assessment identified clinical findings that differentiated them from children with idiopathic autism. These and prior data suggest a disturbance of mitochondrial energy production as an underlying pathophysiological mechanism in a subset of individuals with autism.

Escherichia coli O157:H7-induced hemolytic-uremic syndrome: histopathologic changes in the colon over time

The 1993 E. coli O157:H7 epidemic in the Western United States has provided a unique opportunity to evaluate the histopathologic temporal progression of disease in the colon in children who developed hemolytic uremic syndrome (HUS). In this report we briefly summarize the clinical courses of eight patients and then discuss the colonic pathology observed in specimens obtained at surgery or at the time of autopsy. The patients were divided into two groups: group 1 consisted of six subjects whose colonic samples were obtained during the acute phase of disease, and group 2 consisted of two subjects whose samples were obtained late in their disease. Both the gross and microscopic findings showed that the most severely affected as well as the earliest affected regions of the colon were the left and transverse portions. Only later in the disease progression was there right-sided colon involvement. These findings are in contrast to the distribution described in E. coli O157:H7 hemorrhagic colitis without HUS, thus suggesting a different mechanism of injury.

Dietary protein intolerance in infants with transient methemoglobinemia and diarrhea

Of 17 infants requiring hospitalization for primary soy or cow milk protein intolerance, six infants (35%) had transient methemoglobinemia. Reexposure to the offending protein caused diarrhea, metabolic acidosis, and transient methemoglobinemia in all patients. These six patients represented 65% of the total hospitalizations resulting from methemoglobinemia of any cause.