Asperger Syndrome Health Article

Diagnosis

As of 2005, there are no blood tests or brain scans that can be used to diagnose AS. Until DSM-IV (1994), there was no official list of symptoms for the disorder, which made its diagnosis both difficult and inexact. Although most children with AS are diagnosed between five and nine years of age, many are not diagnosed until adulthood. Misdiagnoses are common; AS has been confused with such other neurological disorders as Tourette syndrome, or with attention-deficit disorder (ADD), oppositional defiant disorder (ODD), or obsessive-compulsive disorder (OCD). Some researchers think that AS overlaps with some types of learning disability, such as the nonverbal learning disability (NLD) syndrome identified in 1989. As of 2005, there is no clear answer to the question of whether AS is a distinct syndrome or a subtype of autism.

The inclusion of A syndrome as a separate diagnostic category in DSM-IV was justified on the basis of a large international field trial of more than 1,000 children and adolescents. Nevertheless, the diagnosis of AS is also complicated by confusion with such other diagnostic categories, such as high-functioning (IQ >70) autism (HFA) and schizoid personality disorder of childhood. With regard to schizoid personality disorder, Asperger syndrome does not have an unchanging set of personality traits, but has a developmental dimension. AS is distinguished from HFA by the following characteristics:

• later onset of symptoms (usually around three years of age)
• early development of grammatical speech (the AS child's verbal IQ is usually higher than performance IQ—the reverse being the case in autistic children)
• less severe deficiencies in social and communication skills
• presence of intense interest in one or two topics
• physical clumsiness and lack of coordination
• family is more likely to have a history of the disorder
• lower frequency of neurological disorders
• more positive outcome in later life

DSM-IV criteria for Asperger syndrome

DSM-IV specifies six diagnostic criteria for AS:

• The child's social interactions are impaired in at least two of the following ways: markedly limited use of nonverbal communication; lack of age-appropriate peer relationships; failure to share enjoyment, interests, or accomplishment with others; lack of reciprocity in social interactions.
• The child's behavior, interests, and activities are characterized by repetitive or rigid patterns, such as an abnormal preoccupation with one or two topics, or with parts of objects; repetitive physical movements; or rigid insistence on certain routines and rituals.
• The affected individual's social, occupational, or educational functioning is significantly impaired.
• The child has normal age-appropriate language skills.
• The child has normal age-appropriate cognitive skills, self-help abilities, and curiosity about the environment.
• The child does not meet criteria for another specific PDD or schizophrenia.

Other diagnostic scales and checklists

Other instruments that have been used to identify children with AS include Gillberg's criteria, a six-item list compiled by a Swedish researcher that specifies problems in social interaction, a preoccupying narrow interest, forcing routines and interests on the self or others, speech and language problems, nonverbal communication problems, and physical clumsiness; and the Australian Scale for Asperger Syndrome (ASAS), a detailed multi-item questionnaire developed in 1996.

Brain imaging findings

As of 2005, only a few structural abnormalities of the brain have been linked to AS. Findings include abnormally large folds in the brain tissue in the left frontal region, abnormally small folds in the operculum (a lid-like structure composed of portions of three adjoining brain lobes), and damage to the left temporal lobe. The first brain imaging study (using single-photon emission tomography [SPECT]) of patients with AS found a lower-than-normal blood supply in the left parietal area of the brain. Brain imaging studies on a larger sample of patients is the next stage of research.

Treatment and management

As of 2005, there is no cure for AS and no prescribed regimen for affected patients. Specific treatments are based on the individual's symptom pattern.

Medications

The drugs that are recommended most often for children with AS include psychostimulants (methylphenidate, pemoline), clonidine, or one of the tricyclic antidepressants (TCAs) for hyperactivity or inattention; beta blockers, neuroleptics, or lithium for anger or aggression; selective serotonin reuptake inhibitors (SSRIs) or TCAs for rituals and preoccupations; and SSRIs or TCAs for anxiety symptoms. One alternative herbal remedy that has been tried with AS patients is St. John's Wort.

Psychotherapy

Individuals with Asperger syndrome often benefit from psychotherapy, particularly during adolescence, in order to cope with depression and other painful feelings related to their social difficulties.