July 16, 2018Quiz
Autism is a developmental disorder characterized by troubles with social interaction and communication and by restricted and repetitive behavior. Parents usually notice signs in the first two or three years of their child's life. These signs often develop gradually, though some children with autism reach their developmental milestones at a normal pace and then worsen. In the United States, a revision from autism to autism spectrum disorder (ASD) was presented in the Diagnostic and Statistical Manual of Mental Disorders version 5 (DSM-5), released May 2013. The new diagnosis encompasses previous diagnoses of 1) ___ disorder, Asperger syndrome, childhood disintegrative disorder, and PDD-NOS. Compared with the DSM-IV diagnosis of autistic disorder, the DSM-5 diagnosis of ASD no longer includes communication as a separate criterion and has merged social interaction and communication into one category. Slightly different diagnostic definitions are used in other countries. For example, the ICD-10 is the most commonly-used diagnostic manual in the UK and European Union. Rather than categorizing these diagnoses, the DSM-5 has adopted a dimensional approach to diagnosing disorders that fall underneath the autism spectrum umbrella. Some have proposed that individuals on the autism spectrum may be better represented as a single diagnostic category. Within this category, the DSM-5 has proposed a framework of differentiating each individual by dimensions of severity, as well as associated features (i.e., known genetic disorders, and intellectual disability). Another change to the DSM includes collapsing social and communication deficits into one domain. Thus, an individual with an ASD diagnosis will be described in terms of severity of social communication symptoms, severity of fixated or restricted behaviors or interests, and associated features. The restricting of onset age has also been loosened from 3 years of age to "early developmental period", with a note that symptoms may manifest later when social demands exceed capabilities.
Autism spectrum, also known as autism spectrum 2) ___ (ASD), is a range of conditions classified as neurodevelopmental disorders. Individuals diagnosed with autism spectrum disorder present with two types of symptoms: problems in social communication and social interaction, and restricted, repetitive patterns of behavior, interests or activities. Symptoms are typically recognized between 3) ___ and two years of age. Long term issues may include difficulties in creating and keeping relationships, maintaining a job, and performing daily tasks. The cause of autism spectrum is uncertain. Risk factors include having an 4) ___ parent, a family history of the condition, and certain genetic conditions. Diagnosis is based on symptoms. The DSM-5 redefined the autism spectrum disorders to encompass the previous diagnoses of autism, Asperger syndrome, pervasive developmental disorder not otherwise specified (PDD-NOS), and childhood disintegrative disorder. Treatment efforts are generally individualized to the person's condition. Medications may be used to try to help improve certain associated problems. Evidence to support the use of medications, however, is not very strong. Autism spectrum is estimated to affect about 1% of people (62.2 million globally as of 2015). Males are diagnosed more often than females.
Autism risk factors include certain infections during pregnancy, such as rubella, as well as valproic acid, alcohol or cocaine use during pregnancy. Controversies surround other proposed environmental causes, for example the vaccine hypotheses, which have been disproven. Autism affects information processing in the brain by altering how nerve cells and their 5) ___ connect and organize; how this occurs is not well understood. Early speech or behavioral interventions can help children with autism gain self-care, social skills and communication skills. Although there is no known 6) ___, there have been cases of children who have recovered from the condition. Not many children with autism live independently after reaching adulthood, though some are successful.
Globally, autism is estimated to affect 24.8 million people as of 2015. In the developed countries, about 1.5% of children are diagnosed with ASD as of 2017, a more than doubling from 0.7% in 2000 in the United States. It occurs four-to-five times more often in boys than girls. The number of people diagnosed has increased dramatically since the 1960s, partly due to changes in diagnostic practice; the question of whether actual rates have increased is unresolved. Overt symptoms gradually begin after the age of six months, become established by age two or three years and tend to continue through adulthood, although often in more muted form. Other aspects, such as atypical eating, are also common but are not essential for diagnosis. Individual symptoms of autism occur in the general population and appear not to associate highly, without a sharp line separating pathologically severe from common traits.
Social deficits distinguish autism and the related autism spectrum disorders from other developmental disorders. People with autism have social impairments and often lack the intuition about others that many people take for granted. Noted autistic Temple Grandin described her inability to understand the social communication of neurotypicals, or people with normal neural development, as leaving her feeling "like an anthropologist on Mars." One year after researchers published their work on a physiological test for autism, a follow-up study confirmed its exceptional success in assessing whether a child is on the autism spectrum. A physiological test that supports a clinician's diagnostic process has the potential to lower the age at which children are diagnosed, leading to earlier treatment. Results of the study, which uses an algorithm to predict if a child has ASD based on metabolites in a 7) ___ sample, published in the June 2018 edition of Bioengineering & Translational Medicine. The study was able to predict with 88% accuracy whether children have autism. The initial success in 2017 analyzed data from a group of 149 people, about half of whom had been previously diagnosed with ASD. For each member of the group, data was obtained on 24 metabolites related to the two cellular pathways -- the methionine cycle and the transsulfuration pathway. To validate the results, existing datasets were searched that included the metabolites that were analyzed in the original study. Datasets were identified that included a total of 154 children with autism. The team used their approach to recreate the predictive 8) ___, this time using data of the 22 metabolites from the original group of 149 children. The algorithm was then applied to the new group of 154 children for testing purposes. When the predictive algorithm was applied to each individual, it correctly predicted autism with 88% accuracy. This is an approach should support moving forward into 9) ___ trials and ultimately into a commercially available test. Sources: Multivariate techniques enable a biochemical classification of children with autism spectrum disorder versus typically-developing peers: A comparison and validation study. Bioengineering & Translational Medicine, 2018; DOI: 10.1002/btm2.10095; Rensselaer Polytechnic Institute. "Success of blood test for autism affirmed: First physiological test for autism proves high accuracy in second trial." ScienceDaily.com, 19 June 2018; Wikipedia
Cerebrospinal fluid (CSF) may be an early marker for autism.
CSF is a colorless fluid that surrounds the brain and spinal cord. CSF acts as a physical buffer to protect the 10) ___from jolts. Until relatively recently, this was thought to be CSF's only role. However, recent studies have shown that CSF also acts as a filtration system for byproducts of brain metabolism. As brain cells fire, they produce toxic products such as inflammatory proteins. The CSF filters out these compounds regularly, replenishing itself around four times per day. A study published in Biological Psychiatry show that levels of this fluid could potentially predict autism. The study looked at CSF and its relationship with autism. The findings showed that babies who went on to develop autism had significantly more CSF than babies who did not go on to develop the condition. Sources: Biological Psychiatry, August 2017.
ANSWERS: 1) autistic; 2) disorder; 3) one; 4) older; 5) synapses; 6) cure; 7) blood; 8) algorithm; 9) clinical; 10) brain