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Autism and the pervasive developmental disorders
Current Paediatrics (1997) 7, 158 162 © 1997 Pearson Professional Ltd
Mini-symposium: Neurology
Autism and the pervasive developmental disorders
J. G. S. Prosser, A. S. Le Couteur
while in others, striking abnormalities and challenging behaviours mask the pathomnemonic features (Case 2). The level of intellectual impairment (over 70% will have a learning disability) has a significant impact on the observed behavioural characteristics. Deficits in communication are more pronounced, there are fewer adaptive behaviours, and there is a greater degree of repetitive stereotyped behaviours. Autism is held to be diagnosable in 4 to 5 per 10 000 of the population, although the true figure may be as high as 10 per 10 0001 and males are three times more likely to be affected than females. Despite a perception among professionals that the incidence is increasing, there has to date been no persuasive evidence in support of this. 2 Asperger's syndrome (Case 3) differs from autism in that there is no delay in language development and no intellectual impairment. Social and behavioural abnormalities are, generally, less extreme and this often results in recognition in later childhood, when an increasing divergence in social ability and higher order language skills is noticed between the child and his peers. There is often a history of circumscribed interests, unusually intense preoccupations and a rigid adherence to daily routines. The male preponderance in Asperger's syndrome is even more pronounced than in autism and many individuals are reported as significantly clumsy.
INTRODUCTION Autism and the other pervasive developmental disorders constitute an important part of the work referred to developmental paediatricians and pre-school child psychiatrists. The lifelong course of the difficulties, the implications for educational provision and the potential for family disruption necessitate accurate diagnosis and comprehensive planning as early as possible. In this paper we will define the term 'pervasive developmental disorder' (PDD), illustrating the key qualitative abnormalities and the considerable heterogeneity in clinical presentation; and the challenge this poses for the subclassification of these disorders. Current understanding of the aetiology of PDD will be briefly reviewed. Guidelines for the assessment of these cases will be outlined before finally introducing some contemporary themes in management.
PHENOMENOLOGY The pervasive developmental disorders are a group of neurodevelopmental disorders with key cognitive and behavioural deficits in common. They are typified by autism, a characteristic pattern of delays or deviances in aspects of social development, abnormalities in verbal and non-verbal communication and abnormally repetitive and stereotyped play and behaviour. There can be a wide variation in the clinical presentation of children with the disorder. Some individuals display the classic picture of core autism (Case 1),
CLASSIFICATION Autism is probably the best validated child psychiatric disorder. 3Research has led to an increasing consensus about the features of core autism4 and there are operational criteria for the diagnosiss (Table). However, it is clear that a large number of children and young people present with syndromes that have many features in common with autism, but which do not fulfil
IDr J. Prosser, Clinical Lecturer, Professor A. Le Couteur, Academic Department of Child and Adolescent Mental Health, Fleming Nuffleld Unit, Burdon Terrace, Jesmond, Newcastle, NE2 3AE, UK.
Correspondence and requests for offprints to JGSR
158
Autism and pervasive developmental disorders Table
159
DSM-IV Diagnostic criteria for autistic disorder
A ~ A total of six or more items from 1, 2 and 3 with at least two from 1 and one each from 2 or 3 (1) Qualitative impairment in social interaction, as manifested by two or more of the following: • • • •
marked impairment in the use of multiple non-verbal behaviours such as eye-to-eye gaze, facial expression, body postures and gestures to regulate social interaction failure to develop peer relationships appropriate to developmental level a lack of spontaneous seeking to enjoyment, interests or achievements with other people lack of social or emotional reciprocity
(2) Qualitative impairment in communication, as manifested by at least one of the following: • • • •
delay in, or total lack of, the development of spoken language (not accompanied by an attempt to compensate through alternative modes of communication such as gesture or mime) individuals with adequate speech, marked impairment in the ability to initiate or sustain conversation with others stereotypes and repetitive use of language or idiosyncratic language lack of varied, spontaneous make-believe play or social imitative play appropriate to the developmental level
(3) Restricted repetitive and stereotypes patterns of behaviour, interests, and activities, as manifested by at least one of the following: •
encompassing preoccupation with one or more stereotypes and restricted patterns of interest that is abnormal either in intensity or fOCUS • apparently inflexible adherence to specific, non-functional routines or rituals • stereotyped and repetitive motor mannerisms (e.g. hand or finger flapping or twisting, or complex whole body movements) • persistent pre-occupation with parts of objects B--Delays or abnormal functioning in at least one of the following areas with onset prior to age 3 years: (1) social interaction, (2) language as used in social communication or (3) symbolic or imaginative play C ~ h e disturbance is not better accounted for by Rett's disorder or childhood disintegrative disorder
currently accepted diagnostic criteria. There is no longer any dispute that these states represent disorders related to autism; the uncertainty arises with respect to the nosological validity of the sub-groupings currently employed, and whether different presentations are functions of severity on a continuum of disorder or discrete clinical entities. Does Asperger's syndrome, for example, represent a separate disorder, or is it simply a mild form of autism? Rett's syndrome and Childhood Disintegrative Disorder are classified as pervasive developmental disorders. These organic conditions have some qualitative similarities in the nature of symptoms, but they run a deteriorating course and will not be covered in this review. In family studies of autism, some relatives of autistic probands have been found to display a range of qualitatively similar behaviours, but of a lesser severity than that seen in core autism. These features may represent a 'broader phenotype' of PDD 6 though this has not been studied in the general population. The boundary between these states and normality is not clear.
AETIOLOGY Studies have shown autism to be associated with known medical conditions in about 10% of cases, though others believe the proportion to be higher. The strength of association between autism and these conditions strengthens with decreasing intellect.7 The large majority of cases of autism are idiopathic. Research on this idiopathic group have strongly implicated genetic factors in the aetiology? In the sibship of a child with autism there is a 3-5% risk that another child will also have autism and a 10 20%
chance of a sibling having difficulties within the broader phenotype. Twin and family studies to date suggest a 3 10 gene oligogenic mode of inheritance. It is not yet clear whether there are linear pathways between this genetic pre-disposition and behavioural expression. Pockets of evidence exist at many levels of enquiry between genes and behaviour and Bailey and colleagues9 have reviewed some of this evidence in an attempt to integrate existing knowledge. Neurobiological studies have yielded few replicable results; the frequent finding of increased head circumference may be a reflection of increased brain volume or a familial trait; neuro-imaging studies have reported a number of different findings including cerebellar and medial temporal lobe abnormalities; cerebral metabolism may be diffusely increased or show abnormal relative differences and asymmetries. Advances in neuro-imaging and functional imaging technologies are likely to yield more robust findings over the next few years. In studies of cognitive psychology in autism, there have been findings of abnormal executive functioning and impaired central coherence for sensory stimuli, other groups have developed theories of deficits in much more specific areas of cognitive function, such as socio-affective understanding, theory of mind, and face processing abnormalities. Behavioural psychologists have attempted to elucidate the complex interaction between the child and its environment, proposing behavioural explanations for the persistence of unusual behaviours. 1° These hypotheses are hard to test and are not among the best accepted aetiological theories. Overall the research remains patchy but the multiplicity of research approaches looks destined to provide an integration in the future.
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Current Paediatrics
ASSESSMENT A child presenting with any complex developmental disorder needs a comprehensive multi-disciplinary assessment. Where a PDD is suspected, there should be a psychiatric assessment, a paediatric neurodevelopmental assessment, a psychometric assessment, and a speech and language therapy assessment. This may be undertaken by a single team, or arranged piecemeal where local services allow. The assessment should include direct observations of the child across a number of different settings, with a detailed developmental history from parents or carers. In order to minimize the effect of informant beliefs about the meaning of their child's behaviours, it is wise to use a semi-structured assessment schedule such as the Autism Diagnostic Interview (ADI), H,~2 where the emphasis is placed on identifying whether examples of observable behaviour are or were present at key stages in development. The paediatric neurodevelopmental assessment will include details of birth history, developmental milestones, a neurodevelopmental examination, hearing and sight tests, and blood tests. The degree to which one should pursue medical investigations has been a source of debate. Since 50% of individuals with autism have an abnormal EEG ~3and 25% have epilepsy, some advocate an EEG routinely, especially in the light of a possible association between abnormal EEG, epilepsy and developmental regression? 4 Others will only perform an EEG where there is a history of episodic variation in symptomatology. Similarly, tests for chromosomal abnormalities, including fragile-X syndrome, are often performed routinely, but some centres require a higher index of suspicion than merely the presence of PDD symptoms.
FORMULATION AND MANAGEMENT The assessment should result in a formulation of the child's individual pattern of skills and difficulties that is understood and accepted by parents and professionals. The formulation should make reference to the impact of the condition on the family and any variations in the child's behaviour from one setting to another. The first task of management, which can begin successfully during the initial assessment, is to form a therapeutic alliance with the family of the affected child. This occurs when families feel listened to, their experiences validated, and their concerns taken seriously. It is wise to adopt the priorities of the family, usually for suitable educational provision and advice on management in the home as the primary focus for intervention.
Provision of information Parents commonly request information about the PDDs during or after an assessment. The clinician is
in a good position to provide general information and answers to many of the initial questions. There are a variety of lay texts readily available? 5,~ In addition, The National Autistic Society~7has become an invaluable resource for parents and professionals alike, providing information on mainstream health and educational resources as well as news of innovative and complimentary treatments. It maintains an active internet web site TM with links to experimental treatments of autism and other pervasive developmental disorders.
Pre-school (early) intervention There is an increasing awareness of PDD among parents and professionals which is resulting in earlier presentation to services and, therefore, the opportunity for early intervention. Indeed, some suggest screening for autism in infancy to encourage this?9 Though as yet systematically unproven, a focus on the development of communication and social behaviour in the pre-school child with PDD may have very significant benefits for later functioning, and there are reports that gains made in such programmes seem to persist for years after intervention.2° Early intervention packages commonly include detailed work with individual parents on management in the home, parental support groups and individual work with the child in a specialist day placement. Early intervention packages are sought after by parents and much appreciated where present.
Schooling Children with pervasive developmental disorders usually have special educational needs. They may require specific styles of teaching often with a high staff to pupil ratio, incorporating highly structured timetabling, tasks meaningful to the child, and clear, unambiguous instructions. The initial need for predictability in teaching patterns may gradually be relaxed as the skill of flexibility emerges. Unstructured time, such as breaks, physical education, assemblies and 'free time' can be especially difficult. Strategic planning for these times, perhaps articulated in a statement of special educational needs, helps to keep the focus on the development of specific social skills which may be taken for granted in most children in mainstream and special educational settings.
Home The current emphasis for therapeutic intervention focuses on working with parents and families on the management of the autistic child at home. This complements the work done in schools in encouraging the development of adaptive behaviours. Because many autistic children have difficulty in generalizing these adaptive behaviours from one setting to another, there
Autism and pervasive developmental disorders is a clear need for close collaboration between school and home in order to provide consistent management across settings towards agreed goals. To maximize potential scholastic and social abilities of the affected child, it is necessary to pay close attention to the degree of sensory stimulation of the environment, the degree of structure and predictability of activities, and to developing effective styles of communication with the child.
Social training Social training in later childhood and adolescence, often in a group setting, has proved a useful intervention where an inability to read subtle social situations has a detrimental social impact in an otherwise intellectually able young person. Such young people may not understand the purpose of the complex social rules which govern social functioning but there is evidence that affected individuals can learn the social rules. It has proven much harder to instill a flexibility in the application of these social rules to everyday life.21
161
CASE 1 CORE AUTISM James has been referred because his nursery teachers think he might have autism. He is now 41 years old and his development has been a source of concern since he was 18 months old by which time he had not babbled or used words. His hearing was found to be normal. In the clinic he is constantly occupied with a calculator which he carries around with him. He is reported to spend his time at home either repeatedly watching the same section of a 'Thomas the Tank Engine' video or playing with his calculator. Whilst he frequently recites fragments of the script of the video, he is only able to express his basic needs using simple two-word combinations. He is more likely to attempt to meet his own needs himself, for example by climbing to reach high cupboards to obtain biscuits, which along with other dry foods, 'are among the only things he will eat. He rarely acknowledges the presence of adults or peers unless they interfere with his activity whereupon he will usually move away. He occasionally makes prolonged staring eye contact. This is not responsive to social regulation by adults, and his mother reports the sensation of his 'looking through' her.
Family work Family functioning is unavoidably affected when a child suffers from a pervasive developmental disorder. Frequently, families reorganize their lives around the needs of the affected child, to the detriment of parental employment, marital relations, family social activity and sibling relationships. The clinician needs to be aware of the impact of the developmental problems on the family, and may consider with the family the usefulness of respite services, parental support groups, community workers and family therapy.
Physical and other innovative treatments While the principles of psychosocial and educational management outlined previously are now widely accepted, new approaches are being developed all the time. Some, such as the TEACCH method and Higashi schooling, have become well established. Physical treatments may be of benefit in some clinical cases and developments in these treatments are followed with great interest by parents and special interest groups. Such initiatives have included the use of medication (including anti-epileptics), restrictive diets, interventions aimed at sensory integration (Sound and Light Therapy, Irlen Spectacles), and interventions designed to foster alternative means of communication such as 'facilitated communication'. Anecdotal evidence of the value of these 'therapies' is, in some cases, beginning to be supported in clinical trials but as yet there is no systematic evidence of their efficacy.
CASE 2 AUTISM WITH INTELLECTUAL DISABILITY Grace is 12 and attends a school for severe learning difficulties. She has been referred for assessment of her self-injurious behaviour. She bites the back of both hands and strikes her forehead repeatedly. Grace has up to six grand mal seizures a day although previous medical assessment has excluded tuberose sclerosis and other medical conditions. She uses no meaningful language, although she can understand and use about 30 MAKATON signs which she uses to communicate her basic needs. She spends much of her day engrossed in play with a strand of hair in her peripheral vision, hand-flapping every few seconds. She rocks vigorously and wanders around the room on her toes. She screams if a deviation is made in her route to school, or if ornaments are moved in her home, and major tantrums have occurred when the phone at home is aligned slightly differently to usual. Her distress is manifested irrespective of whether anyone is present or not. Her mother believes that Grace recognizes her, having noticed an increase in hand flapping upon her return from shopping trips but most people who know her report that she does not seem to notice the presence of people at all. She laughs out loud at unexpected times, but not usually when those around her are laughing.
CASE 3 ASPERGER'S SYNDROME Ronnie is 9 years old and was referred by his educational psychologist who believes his problems are
162
Current Paediatrics
more widespread than the specific difficulty with literacy skills previously diagnosed. His teachers regard him as bright, exceptionally so in number tasks, but find him hard to teach, complaining he does not listen and is often 'in a world of his own'. It has been noticed that his written work is not only messy, but not in keeping with his general intellectual ability. His behaviour is odd and socially gauche. He has not developed any friendships and seems happier in the company of supervising staff. He is reported as a clumsy boy and is unable to kick or catch a ball. Furthermore, he is seemingly unable to follow the rules of simple games with his peers, and is often rejected by them for attempting to control their play. He has a special interest in the Vikings, engaging anyone who will listen in a presentation of his impressive knowledge on the subject. However, it is difficult to engage him in a conversation, even on his favourite topics, since he allows no space for questions or interruptions from the listener.
CONCLUSION
Our state of knowledge about the pervasive developmental disorders is in a state of rapid growth. Advances in treatment have been matched with a greater understanding of psychopathological processes. It is likely that there will be further significant developments in the assessment and treatment of these fascinating disorders by the bringing together of clinical experience, academic endeavour, family perspectives and public support. REFERENCES
1. Bryson S E. Epidemiology of autism. J Autism Dev Disord 1996; 6(2): 165 167. 2. Wing L. Autistic spectrum disorders: no evidence for or against an increase in prevalence. Br Med J 1996; 312: 327-328.
3. Lord C, Rutter M. Autism and pervasive developmental disorders. In: Rutter M, Taylor E, Hersov L, eds. Child and Adolescent Psychiatry: Modern Approaches, 3rd edn. Oxford: Blackwell, 1994:569 593. 4. Volkmar F R, Cicchetti D V, Bregman J, Cohen D J. Three diagnostic systems for autism: DSM-III, DSM-III-R, and ICD-10. J Autism Dev Disord 1992; 22(4): 483-492. 5. American Psychiatric Association. Diagnosis and statistical manual of mental disorders: DSM-IV. Washington; American Psychiatric Association, 1994. 6. Le Couteur A, Bailey A, Goode Set al. A broader phenotype of autism: the clinical spectrum in twins. J Child Psychol Psychiatry 1996; 37(7): 785-801. 7. Rutter M, Bailey A, BoRon P, Le Couteur A. Autism and known medical conditions: myth and substance. J Child Psychol Psychiatry 1994; 35(2): 311-322. 8. Bailey A, Le Couteur A, Gottesman I e t al. Autism as a strongly genetic disorder: evidence from a British twin study. Psychol Med 1995; 25: 63-77. 9. Bailey A, Phillips W, Rutter M. Autism: towards an integration of clinical, genetic, neuropsychological, and neurobiological perspectives. J Child Psychol Psychiatry 1996; 37(1): 89-126. 10. Lovaas O I, Smith T. A comprehensive behavioral theory of autistic children: paradigm for research and treatment. J Behav Ther Exp Psychiatry 1989; 20(1): 17-29. 11. Le Couteur A, Rutter M, Lord C et al. Autism Diagnostic Interview: a standardized investigator-based instrument. J Antism Dev Disord 1989; 19(3): 363-387. 12. Lord C, Rutter M, Le Couteur A. Autism Diagnostic Interview - Revised: a revised version of a diagnostic interview for caregivers of individuals with possible pervasive developmental disorders. J Autism Dev Disord i994; 24(5): 659-685. 13. Minshew N. Indices of neural function in autism: clinical and biological implications. Pediatrics 1991; 31: 774-780. 14. Tuchman R I, Rapin I. Regression in pervasive developmental disorders: seizures and epileptiform electroencephalogram correlates. Pediatrics 1997; 99(4): 560 566. 15. Wing L. The autistic spectrum: a guide for parents and professionals. London; Constable, 1996. 16. Baron-Cohen S, BoRon R Autism: the facts. Oxford; Oxford University Press, 1993. 17. The National Autistic Society; 276 Willesden Lane, London, NW2 5RB. 18. http://www.oneworld.org/antism_uld 19. Baron-Cohen S, Cox A, Baird G. Psychological markers in the detection of autism in infancy in a large population. Br J Psychiatry 1996; 168: 158-163. 20. Rogers S J. Early intervention in autism. J Autism Dev Disord 1996; 26(2): 243-246. 21. Howlin P, Rutter M. Treatment of autistic children. Chichester; Wiley, 1989.
Mini-symposium: Neurology
Autism and the pervasive developmental disorders
J. G. S. Prosser, A. S. Le Couteur
while in others, striking abnormalities and challenging behaviours mask the pathomnemonic features (Case 2). The level of intellectual impairment (over 70% will have a learning disability) has a significant impact on the observed behavioural characteristics. Deficits in communication are more pronounced, there are fewer adaptive behaviours, and there is a greater degree of repetitive stereotyped behaviours. Autism is held to be diagnosable in 4 to 5 per 10 000 of the population, although the true figure may be as high as 10 per 10 0001 and males are three times more likely to be affected than females. Despite a perception among professionals that the incidence is increasing, there has to date been no persuasive evidence in support of this. 2 Asperger's syndrome (Case 3) differs from autism in that there is no delay in language development and no intellectual impairment. Social and behavioural abnormalities are, generally, less extreme and this often results in recognition in later childhood, when an increasing divergence in social ability and higher order language skills is noticed between the child and his peers. There is often a history of circumscribed interests, unusually intense preoccupations and a rigid adherence to daily routines. The male preponderance in Asperger's syndrome is even more pronounced than in autism and many individuals are reported as significantly clumsy.
INTRODUCTION Autism and the other pervasive developmental disorders constitute an important part of the work referred to developmental paediatricians and pre-school child psychiatrists. The lifelong course of the difficulties, the implications for educational provision and the potential for family disruption necessitate accurate diagnosis and comprehensive planning as early as possible. In this paper we will define the term 'pervasive developmental disorder' (PDD), illustrating the key qualitative abnormalities and the considerable heterogeneity in clinical presentation; and the challenge this poses for the subclassification of these disorders. Current understanding of the aetiology of PDD will be briefly reviewed. Guidelines for the assessment of these cases will be outlined before finally introducing some contemporary themes in management.
PHENOMENOLOGY The pervasive developmental disorders are a group of neurodevelopmental disorders with key cognitive and behavioural deficits in common. They are typified by autism, a characteristic pattern of delays or deviances in aspects of social development, abnormalities in verbal and non-verbal communication and abnormally repetitive and stereotyped play and behaviour. There can be a wide variation in the clinical presentation of children with the disorder. Some individuals display the classic picture of core autism (Case 1),
CLASSIFICATION Autism is probably the best validated child psychiatric disorder. 3Research has led to an increasing consensus about the features of core autism4 and there are operational criteria for the diagnosiss (Table). However, it is clear that a large number of children and young people present with syndromes that have many features in common with autism, but which do not fulfil
IDr J. Prosser, Clinical Lecturer, Professor A. Le Couteur, Academic Department of Child and Adolescent Mental Health, Fleming Nuffleld Unit, Burdon Terrace, Jesmond, Newcastle, NE2 3AE, UK.
Correspondence and requests for offprints to JGSR
158
Autism and pervasive developmental disorders Table
159
DSM-IV Diagnostic criteria for autistic disorder
A ~ A total of six or more items from 1, 2 and 3 with at least two from 1 and one each from 2 or 3 (1) Qualitative impairment in social interaction, as manifested by two or more of the following: • • • •
marked impairment in the use of multiple non-verbal behaviours such as eye-to-eye gaze, facial expression, body postures and gestures to regulate social interaction failure to develop peer relationships appropriate to developmental level a lack of spontaneous seeking to enjoyment, interests or achievements with other people lack of social or emotional reciprocity
(2) Qualitative impairment in communication, as manifested by at least one of the following: • • • •
delay in, or total lack of, the development of spoken language (not accompanied by an attempt to compensate through alternative modes of communication such as gesture or mime) individuals with adequate speech, marked impairment in the ability to initiate or sustain conversation with others stereotypes and repetitive use of language or idiosyncratic language lack of varied, spontaneous make-believe play or social imitative play appropriate to the developmental level
(3) Restricted repetitive and stereotypes patterns of behaviour, interests, and activities, as manifested by at least one of the following: •
encompassing preoccupation with one or more stereotypes and restricted patterns of interest that is abnormal either in intensity or fOCUS • apparently inflexible adherence to specific, non-functional routines or rituals • stereotyped and repetitive motor mannerisms (e.g. hand or finger flapping or twisting, or complex whole body movements) • persistent pre-occupation with parts of objects B--Delays or abnormal functioning in at least one of the following areas with onset prior to age 3 years: (1) social interaction, (2) language as used in social communication or (3) symbolic or imaginative play C ~ h e disturbance is not better accounted for by Rett's disorder or childhood disintegrative disorder
currently accepted diagnostic criteria. There is no longer any dispute that these states represent disorders related to autism; the uncertainty arises with respect to the nosological validity of the sub-groupings currently employed, and whether different presentations are functions of severity on a continuum of disorder or discrete clinical entities. Does Asperger's syndrome, for example, represent a separate disorder, or is it simply a mild form of autism? Rett's syndrome and Childhood Disintegrative Disorder are classified as pervasive developmental disorders. These organic conditions have some qualitative similarities in the nature of symptoms, but they run a deteriorating course and will not be covered in this review. In family studies of autism, some relatives of autistic probands have been found to display a range of qualitatively similar behaviours, but of a lesser severity than that seen in core autism. These features may represent a 'broader phenotype' of PDD 6 though this has not been studied in the general population. The boundary between these states and normality is not clear.
AETIOLOGY Studies have shown autism to be associated with known medical conditions in about 10% of cases, though others believe the proportion to be higher. The strength of association between autism and these conditions strengthens with decreasing intellect.7 The large majority of cases of autism are idiopathic. Research on this idiopathic group have strongly implicated genetic factors in the aetiology? In the sibship of a child with autism there is a 3-5% risk that another child will also have autism and a 10 20%
chance of a sibling having difficulties within the broader phenotype. Twin and family studies to date suggest a 3 10 gene oligogenic mode of inheritance. It is not yet clear whether there are linear pathways between this genetic pre-disposition and behavioural expression. Pockets of evidence exist at many levels of enquiry between genes and behaviour and Bailey and colleagues9 have reviewed some of this evidence in an attempt to integrate existing knowledge. Neurobiological studies have yielded few replicable results; the frequent finding of increased head circumference may be a reflection of increased brain volume or a familial trait; neuro-imaging studies have reported a number of different findings including cerebellar and medial temporal lobe abnormalities; cerebral metabolism may be diffusely increased or show abnormal relative differences and asymmetries. Advances in neuro-imaging and functional imaging technologies are likely to yield more robust findings over the next few years. In studies of cognitive psychology in autism, there have been findings of abnormal executive functioning and impaired central coherence for sensory stimuli, other groups have developed theories of deficits in much more specific areas of cognitive function, such as socio-affective understanding, theory of mind, and face processing abnormalities. Behavioural psychologists have attempted to elucidate the complex interaction between the child and its environment, proposing behavioural explanations for the persistence of unusual behaviours. 1° These hypotheses are hard to test and are not among the best accepted aetiological theories. Overall the research remains patchy but the multiplicity of research approaches looks destined to provide an integration in the future.
160
Current Paediatrics
ASSESSMENT A child presenting with any complex developmental disorder needs a comprehensive multi-disciplinary assessment. Where a PDD is suspected, there should be a psychiatric assessment, a paediatric neurodevelopmental assessment, a psychometric assessment, and a speech and language therapy assessment. This may be undertaken by a single team, or arranged piecemeal where local services allow. The assessment should include direct observations of the child across a number of different settings, with a detailed developmental history from parents or carers. In order to minimize the effect of informant beliefs about the meaning of their child's behaviours, it is wise to use a semi-structured assessment schedule such as the Autism Diagnostic Interview (ADI), H,~2 where the emphasis is placed on identifying whether examples of observable behaviour are or were present at key stages in development. The paediatric neurodevelopmental assessment will include details of birth history, developmental milestones, a neurodevelopmental examination, hearing and sight tests, and blood tests. The degree to which one should pursue medical investigations has been a source of debate. Since 50% of individuals with autism have an abnormal EEG ~3and 25% have epilepsy, some advocate an EEG routinely, especially in the light of a possible association between abnormal EEG, epilepsy and developmental regression? 4 Others will only perform an EEG where there is a history of episodic variation in symptomatology. Similarly, tests for chromosomal abnormalities, including fragile-X syndrome, are often performed routinely, but some centres require a higher index of suspicion than merely the presence of PDD symptoms.
FORMULATION AND MANAGEMENT The assessment should result in a formulation of the child's individual pattern of skills and difficulties that is understood and accepted by parents and professionals. The formulation should make reference to the impact of the condition on the family and any variations in the child's behaviour from one setting to another. The first task of management, which can begin successfully during the initial assessment, is to form a therapeutic alliance with the family of the affected child. This occurs when families feel listened to, their experiences validated, and their concerns taken seriously. It is wise to adopt the priorities of the family, usually for suitable educational provision and advice on management in the home as the primary focus for intervention.
Provision of information Parents commonly request information about the PDDs during or after an assessment. The clinician is
in a good position to provide general information and answers to many of the initial questions. There are a variety of lay texts readily available? 5,~ In addition, The National Autistic Society~7has become an invaluable resource for parents and professionals alike, providing information on mainstream health and educational resources as well as news of innovative and complimentary treatments. It maintains an active internet web site TM with links to experimental treatments of autism and other pervasive developmental disorders.
Pre-school (early) intervention There is an increasing awareness of PDD among parents and professionals which is resulting in earlier presentation to services and, therefore, the opportunity for early intervention. Indeed, some suggest screening for autism in infancy to encourage this?9 Though as yet systematically unproven, a focus on the development of communication and social behaviour in the pre-school child with PDD may have very significant benefits for later functioning, and there are reports that gains made in such programmes seem to persist for years after intervention.2° Early intervention packages commonly include detailed work with individual parents on management in the home, parental support groups and individual work with the child in a specialist day placement. Early intervention packages are sought after by parents and much appreciated where present.
Schooling Children with pervasive developmental disorders usually have special educational needs. They may require specific styles of teaching often with a high staff to pupil ratio, incorporating highly structured timetabling, tasks meaningful to the child, and clear, unambiguous instructions. The initial need for predictability in teaching patterns may gradually be relaxed as the skill of flexibility emerges. Unstructured time, such as breaks, physical education, assemblies and 'free time' can be especially difficult. Strategic planning for these times, perhaps articulated in a statement of special educational needs, helps to keep the focus on the development of specific social skills which may be taken for granted in most children in mainstream and special educational settings.
Home The current emphasis for therapeutic intervention focuses on working with parents and families on the management of the autistic child at home. This complements the work done in schools in encouraging the development of adaptive behaviours. Because many autistic children have difficulty in generalizing these adaptive behaviours from one setting to another, there
Autism and pervasive developmental disorders is a clear need for close collaboration between school and home in order to provide consistent management across settings towards agreed goals. To maximize potential scholastic and social abilities of the affected child, it is necessary to pay close attention to the degree of sensory stimulation of the environment, the degree of structure and predictability of activities, and to developing effective styles of communication with the child.
Social training Social training in later childhood and adolescence, often in a group setting, has proved a useful intervention where an inability to read subtle social situations has a detrimental social impact in an otherwise intellectually able young person. Such young people may not understand the purpose of the complex social rules which govern social functioning but there is evidence that affected individuals can learn the social rules. It has proven much harder to instill a flexibility in the application of these social rules to everyday life.21
161
CASE 1 CORE AUTISM James has been referred because his nursery teachers think he might have autism. He is now 41 years old and his development has been a source of concern since he was 18 months old by which time he had not babbled or used words. His hearing was found to be normal. In the clinic he is constantly occupied with a calculator which he carries around with him. He is reported to spend his time at home either repeatedly watching the same section of a 'Thomas the Tank Engine' video or playing with his calculator. Whilst he frequently recites fragments of the script of the video, he is only able to express his basic needs using simple two-word combinations. He is more likely to attempt to meet his own needs himself, for example by climbing to reach high cupboards to obtain biscuits, which along with other dry foods, 'are among the only things he will eat. He rarely acknowledges the presence of adults or peers unless they interfere with his activity whereupon he will usually move away. He occasionally makes prolonged staring eye contact. This is not responsive to social regulation by adults, and his mother reports the sensation of his 'looking through' her.
Family work Family functioning is unavoidably affected when a child suffers from a pervasive developmental disorder. Frequently, families reorganize their lives around the needs of the affected child, to the detriment of parental employment, marital relations, family social activity and sibling relationships. The clinician needs to be aware of the impact of the developmental problems on the family, and may consider with the family the usefulness of respite services, parental support groups, community workers and family therapy.
Physical and other innovative treatments While the principles of psychosocial and educational management outlined previously are now widely accepted, new approaches are being developed all the time. Some, such as the TEACCH method and Higashi schooling, have become well established. Physical treatments may be of benefit in some clinical cases and developments in these treatments are followed with great interest by parents and special interest groups. Such initiatives have included the use of medication (including anti-epileptics), restrictive diets, interventions aimed at sensory integration (Sound and Light Therapy, Irlen Spectacles), and interventions designed to foster alternative means of communication such as 'facilitated communication'. Anecdotal evidence of the value of these 'therapies' is, in some cases, beginning to be supported in clinical trials but as yet there is no systematic evidence of their efficacy.
CASE 2 AUTISM WITH INTELLECTUAL DISABILITY Grace is 12 and attends a school for severe learning difficulties. She has been referred for assessment of her self-injurious behaviour. She bites the back of both hands and strikes her forehead repeatedly. Grace has up to six grand mal seizures a day although previous medical assessment has excluded tuberose sclerosis and other medical conditions. She uses no meaningful language, although she can understand and use about 30 MAKATON signs which she uses to communicate her basic needs. She spends much of her day engrossed in play with a strand of hair in her peripheral vision, hand-flapping every few seconds. She rocks vigorously and wanders around the room on her toes. She screams if a deviation is made in her route to school, or if ornaments are moved in her home, and major tantrums have occurred when the phone at home is aligned slightly differently to usual. Her distress is manifested irrespective of whether anyone is present or not. Her mother believes that Grace recognizes her, having noticed an increase in hand flapping upon her return from shopping trips but most people who know her report that she does not seem to notice the presence of people at all. She laughs out loud at unexpected times, but not usually when those around her are laughing.
CASE 3 ASPERGER'S SYNDROME Ronnie is 9 years old and was referred by his educational psychologist who believes his problems are
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more widespread than the specific difficulty with literacy skills previously diagnosed. His teachers regard him as bright, exceptionally so in number tasks, but find him hard to teach, complaining he does not listen and is often 'in a world of his own'. It has been noticed that his written work is not only messy, but not in keeping with his general intellectual ability. His behaviour is odd and socially gauche. He has not developed any friendships and seems happier in the company of supervising staff. He is reported as a clumsy boy and is unable to kick or catch a ball. Furthermore, he is seemingly unable to follow the rules of simple games with his peers, and is often rejected by them for attempting to control their play. He has a special interest in the Vikings, engaging anyone who will listen in a presentation of his impressive knowledge on the subject. However, it is difficult to engage him in a conversation, even on his favourite topics, since he allows no space for questions or interruptions from the listener.
CONCLUSION
Our state of knowledge about the pervasive developmental disorders is in a state of rapid growth. Advances in treatment have been matched with a greater understanding of psychopathological processes. It is likely that there will be further significant developments in the assessment and treatment of these fascinating disorders by the bringing together of clinical experience, academic endeavour, family perspectives and public support. REFERENCES
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