Misdiagnosis of Asperger's Syndrome as anancastic personality disorder, Letters to the Editor

Michael Fitzgerald Professor Child and Adolescent Psychiatry, Trinity College Dublin Autism 4 Page 435.

Clinical experience suggests that there are quite a number of patients in adult psychiatric hospitals who have been misdiagnosed as having anancastic personality disorder rather than Asperger's Syndrome. While the misdiagnosis of Asperger's Syndrome as simple schizophrenia and other conditions is very familiar, anankastic personality has not been given sufficient consideration in the differential diagnosis. The diagnosis of anankastic personality in ICD-10 is as follows:

1. The individual's characteristics and enduring patterns of inner experience and behaviour as a whole deviate markedly from the culturally expected and accepted range.
2. The deviation manifests itself in a pervasive way with inflexible mal adaptive behaviour.
3. There is personal distress, or adverse impact on the social environment, or both, clearly attributable to the behaviour.

There must be evidence that the deviation is stable and of long duration, having it's onset in late childhood or adolescence. This is one factor that differentiates it from autism which must have an onset in early childhood. The person must meet at least four of the following criteria:

1. preoccupation with details, rules, lists, order, organization or schedule
2. perfectionism that interferes with task completion
3. excessive conscientiousness and scrupulousness
4. excessive pedantry
5. rigidity and stubbornness
6. unreasonable insistence that others submit to exactly his or her way of doing things or unreasonable reluctance to allow others to do things

It is quite clear that autism could easily be mistaken for anankastic personality disorder which has significant implications for clinical interventions.