asperger s syndrome ( as ) , a pervasive neurodevelopmental disorder falling into the autism spectrum disorders , is relatively rare , but many sufferers may not receive appropriate care because as core features could pass undetected or be misdiagnosed . the core features of as are impaired non - verbal communication , restricted interests , and repetitive behavior ( apa 2000 ) . psychiatric co - morbidity , lack of treatment , and complicating social and behavioral factors can all contribute to critical clinical events requiring acute psychiatric admissions . we report a middle - aged male patient admitted to our acute psychiatric unit on account of his psychotic symptoms and impulsive behavior , whose original diagnosis of schizophrenia was reviewed and changed for a diagnosis of as . his behavioral and mental symptoms , including impairing features of as , responded to treatment using aripiprazole , a novel atypical antipsychotic that acts as a partial agonist at the dopamine d2 and serotonin 5ht1a receptors and as an antagonist at the serotonin 5ht2a receptors ( bowels et al 2003 ) . the patient , a 41-year - old male , was compulsorily admitted to our unit after having major anger outbursts at his hostel and threatening staff with a knife . he had previously received a diagnosis of schizophrenia on the basis of his history of unusual behaviors and symptoms such as social withdrawal , concrete thinking and paranoid ideation . more recently he had been accusing the staff of  talking about him and calling him a paedophile , probably an indication of auditory hallucinations , and been reported to repeatedly misinterpret routine conversations as abusive , triggering aggressive responses his parents divorced when he was 3 years old and his mother cared for him . at school he had excelled academically in languages but was clumsy at sport and formed no peer relationships , spending most of his time in the library reading about esoteric subjects . he felt marginalized , said to have been bullied , and was expelled from school at the age of 18 after assaulting a pupil . there was no formal family history of mental illness but his father , a high achieving professional , was described as having a bad temper and being emotionally cold . throughout his adult life he had always found it difficult to establish relationships and sustain employment . in recent years he had developed an intense interest in computer hardware and adopted a repetitive daily routine around this , reacting angrily if this was disrupted . he was referred to mental health services for the first time aged 28 after he was dismissed from his job because of aggressive behavior . he was thought to be depressed and initially received psychotherapy , followed by a trial of fluoxetine , which was discontinued due to side - effects . he was then referred to community mental health services and had been under their care ever since , refusing psychotropic medication whenever this was offered . on admission he presented as a disheveled man who showed high levels of arousal and irritability and who was unwilling to co - operate with the interview , in the course of which he paced around the clinical room . he described his mood as angry but denied any sleep disturbance or changes in his energy levels . he claimed that residents and staff at this hostel had been calling him a  paedophile  and making comments on child abuse with the specific aim of offending him . he spontaneously described being abused at school by a schoolteacher , but this had never been substantiated . on the ward he was noted to be socially withdrawn but his sleep and appetite were normal . his irritability abated after a few days , during which he received no medication but discontinued his cannabis smoking and responded to nursing care . although no further incidents or aggressive outbursts were reported , he remained socially isolated , displaying flat affect yet often evincing irritability and suspiciousness . he was subsequently observed to have awkward , fleeting eye contact , a pedantic and almost theatrical use of language , and a remarkably unchanging facial mimicry . in the absence of any obvious continuing psychotic symptoms , and in view of both his encouraging response to the ward environment and clinical features that seemed to be traits rather than symptoms , we decided to review his diagnosis in the light of dsm - iv criteria for as ( apa 2000 ) , all of which he seemed to meet . we further corroborated the diagnosis of as by applying the autism - spectrum quotient ( aq ) ( baron - cohen et al 2001 ) , a self - rating scale , in which he scored 32 , well above the suggested screening threshold of 26 for an autism - spectrum disorder . we then offered him psycho - education sessions where the diagnosis of as was discussed , as well as reading material on this topic . he read the literature with interest and stated that the diagnosis was a useful way to understand his life - long social and behavioral difficulties . we also suggested that he could benefit from drug treatment using an antipsychotic , as this could reduce his suspiciousness and persistently heightened levels of anxiety , in addition to enhancing his motivation , whereby he could acquire more control over his temper and social interactions . with his consent , he was prescribed aripiprazole orally at an initial dose of 10 mg daily , which he tolerated well and was increased to 15 mg daily after 3 weeks . two weeks after his initial dose the clinical team noted a favorable change in his overall behavior and psychological state as he began to interact with the other patients and actively engage in social activities , such as playing pool and chess and joining occupational therapy groups . the patient himself reported that he felt less anxious and less suspicious and more able to control his temper , enabling him to have more social confidence and interact more with the clinical team . after 4 weeks a meeting was scheduled with his community mental health team and hostel staff to discuss his diagnosis and its implications , and to establish an aftercare plan that took these into account . his participation was remarkably insightful , particularly as he was able to accept that he had been misinterpreting other people s behaviors and responding inappropriately to these . he was willing to return to the hostel and was discharged back to the care of his community team on aripiprazole 15 mg daily . several months later he has remained well and adhering to his treatment , with no adverse effects or further incidents reported . the estimated 4.7/10,000 prevalence of as in the general population probably underestimates the true rate ( lauritsen et al 2004 ) . as may present with symptoms similar to those seen in schizophrenia , depressive disorders and some personality disorders . it may also co - exist with tourette s syndrome and many other clinical conditions ( gillberg and billstadt 2000 ) . this may partly explain why many sufferers receive a diagnosis of as for the first time only after reaching adulthood . as may be associated with psychotic episodes ( who 1992 ) and its clinical features may overlap with symptoms of schizophrenia , especially negative symptoms ( rausch et al 2005 ) . this , and the fact that the former is more rare than the latter , may account for many sufferers who are misdiagnosed as having schizophrenia . among 2500 adults admitted to a psychiatric intensive care unit , 5 ( 0.2% ) received a diagnosis of as for the first time in their lives , which is 4 times the rate in the general population ( raja and azzoni 2001 ) . for this reason , raja and azzoni ( 2001 ) warn against overvaluing psychotic symptoms when specific features of as are present . additional features to substantiate a diagnosis of as may include male gender , clumsiness , and obsessive - compulsive symptoms , as well as violent behavior and unusual restricted interests the patient we described  an adult male of normal intelligence with a history of repetitive behavior , clumsiness , impaired social functioning , aggressive outbursts , and restricted interests in a technically demanding pursuit  met virtually all dsm iv criteria for as ( apa 2000 ) . the ideas of reference and auditory hallucinations he had experienced before admission probably obfuscated his as features , thus culminating in his previous diagnosis of schizophrenia . however , cannabis abuse was probably a major contributing factor to his positive psychotic symptoms , which abated after he discontinued his cannabis consumption . moreover , his features of as , some of which could have been misconstrued as negative symptoms , had only become evident after his cannabis - induced psychotic symptoms had ameliorated . pharmacotherapy is not seen as the ultimate treatment of the core features of as itself but has a definite place in the management of specific troubling symptoms ( bostic and king 2005 ) . yet , in addition to clinical similarities , the neurobiological overlap between as and schizophrenia may provide a tentative rationale for the therapeutic use of antipsychotics in as . like schizophrenia , as has been associated with soft neurological signs ( tani et al 2006 ) , brain maturation abnormalities ( brambilla et al 2004 ) and abnormal central connectivity ( welchew et al 2005 ) . frith ( 2004 ) claimed that core features of as are related to reduced activation and poor connectivity of the medial prefrontal and temporal cortex network , which is the neural substrate of intuitive mentalizing . abnormal fronto - striatal pathways , resulting in defective sensorimotor gating , may lead to difficulties inhibiting repetitive thoughts , speech and actions ( mcalonan et al 2002 ) . also like in schizophrenia , as has been associated with dopamine dysfunction . compared with normal subjects , as patients were found to have increased presynaptic dopamine function in the striatum ( nieminen - von wendt at al 2004 ) . accordingly , dopamine - antagonist antipsychotics such as haloperidol and risperidone have been shown to significantly improve repetitive behavior , aggression , and mood symptoms associated with pervasive developmental disorders ( mcdougle et al 1998 ) . risperidone has been shown to also ameliorate the negative symptoms spectrum associated with as ( rausch et al 2005 ) . however , the use of haloperidol is constrained by the risk of tardive dyskinesia , particularly in the long term , and the use of risperidone by the risk of weight gain and hyperprolactinaemia ( british national formulary 2005 ) . some clinical features of our patient , such as his vulnerably to psychotic symptoms and lifelong suspiciousness , suggested that he could benefit from antipsychotic treatment . aripiprazole is an atypical antipsychotic that has a low potential for inducing extrapyramidal side - effects , hyperprolactinaemia and weight gain ( bowles 2003 ) but , to our knowledge , no systematic study of using aripiprazole to treat as has ever been conducted . yet two findings of a previous study in our unit , which had shown that aripiprazole can be effectively used to treat actively psychotic patients with schizophrenia , indicated that it could also be useful in as . first , therapeutic responses to aripiprazole included the amelioration of negative symptoms ( dratcu et al 2006 ) . second , we found that aripiprazole could prove helpful in the treatment of disorders other than schizophrenia alone where dopamine dysfunction is also thought to play a role , like tardive dyskinesia . after receiving therapeutic doses of aripiprazole for two weeks , the patient experienced a range of positive clinical changes , such as reduced levels of anxiety , arousal and suspiciousness , coupled with improved social interaction and self - control and better insight into his social and psychological difficulties . these were all recognized by the patient himself and sustained as he continued to comply with treatment , in the course of which no adverse reactions were noted . similar findings have been previously reported in a case involving an adult male with a history of intractable as , who responded to aripiprazole after failing to respond to multiple psychological and pharmacological interventions ( staller 2003 ) . like in our patient , responses to aripiprazole included improved sociability and self - awareness , reduced rigidity / anxiety / irritability , and reduced preoccupation with esoteric interests . thus , our findings seem to add to the clinical evidence that , as well as treating psychotic symptoms co - existing with as , some antipsychotics like aripiprazole may potentially ameliorate core features of as itself , a prospect that finds support in the neurobiological overlap of as with schizophrenia . unlike dopamine antagonists , aripiprazole may restore more functional levels of dopaminergic activity because its antagonistic action is dependent on the availability of dopamine itself . if this could explain the therapeutic effects of aripiprazole on the positive and negative symptoms of schizophrenia and in other dopamine - related syndromes , perhaps it may also explain the therapeutic effects of aripiprazole in as , where dopamine dysfunction may likewise be implicated . increasing awareness among clinicians about the diagnosis of as , so that sufferers can be offered appropriate help at earlier stages , is by far the best option to prevent that they are further impaired by the psychiatric and other complications that may ensue . psycho - education can prove invaluable to sufferers , but there are probably many who are likely to also benefit from pharmacological approaches that can attenuate the pervasive and impairing features that they endure . in view of its mode of action and safety profile , and also of the paucity of evidence on alternatives that can be effectively and safely used for this purpose , particularly in the long term , the use of aripiprazole in the treatment of as warrants further scrutiny . such studies are also likely to provide further insights into the pathogenesis and clinical management of as .
asperger s syndrome ( as ) is under - recognized and may be misdiagnosed as schizophrenia in adults because of symptom overlap . pharmacological treatment usually targets associated behavioral and mental symptoms rather than the actual core features of as . 
 we report a middle - aged male patient who , after many years of previous contact with mental health services , and on account of his psychotic symptoms and diagnosis of schizophrenia , was admitted to an inner - city acute psychiatric unit , where a primary diagnosis of as was established for the first time in his life . his impairing clinical features of as improved markedly following treatment using aripiprazole , a novel atypical antipsychotic that acts as a partial agonist at dopamine d2 receptors . as well as sharing clinical features 
 , there is an overlap in underlying neurobiology of as and schizophrenia , including dopamine dysfunction , that provides a rationale for using antipsychotics of this class in the clinical management not only of associated psychotic symptoms but also of the core features of as itself .