Behavior therapy for a child with Lesch-Nyhan syndrome

Phenotype-environment interactions in genetic syndromes associated with severe or profound intellectual disability

The research literature notes both biological and operant theories of behavior disorder in individuals with intellectual disabilities. These two theories of genetic predisposition and operant reinforcement remain quite distinct; neither theory on its own is sufficient to explain challenging behavior in genetic syndromes and an integrated approach is required. This literature review integrates the two approaches by exploring how environmental factors can influence problem behavior in genetic syndromes associated with intellectual disability. Particular attention is paid to studies that describe evidence that problem behaviors in syndromes that are considered to be phenotypic are associated with other aspects of an established behavioral phenotype. The review highlights how the study of phenotype-environment interactions within syndromes can promote understanding of the aetiology of problem behaviors both within genetic syndromes and, ultimately, the wider population of individuals with severe intellectual disabilities. The review also evaluates the current status of research and the methods typically employed. Implications for intervention, future research and extending existing causal models of challenging behavior are discussed.

Working with People with Learning Difficulties Who Self-Injure: A Review of the Literature

Self-injurious behaviour in people with learning difficulties has been found to be a common and health-threatening problem. As a consequence, there is an expanding literature addressing a variety of methods of intervention that are either designed to facilitate or to enforce the reduction or extinction of such behaviour. It is not clear, however, the extent to which such interventions are successful in achieving their avowed goal. This paper critically reviews the treatment of self-injurious behaviour, including work which takes psychodynamic, psychopharmacological, developmental, self-stimulation or learned behaviour perspectives, in order to establish the current status of interventions in this area. It is concluded that no single treatment approach has been shown to be effective in facilitating a reduction in the self-injurious behaviour of all clients. Rather, individualized programmes of intervention need to be constructed, using careful causal and functional analyses of behaviour. Moreover, such programmes, which may be multi-modal in nature, need to aim for interventions that are minimally or non-aversive.

Functional analysis of self-injurious behavior in an adult with Lesch-Nyhan syndrome

A three-phase functional analysis was conducted to discover controlling variables of self-injury in a 28-year-old individual with Lesch-Nyhan syndrome. Experimental verification followed information-gathering and interpretive phases. Self-injurious responses were blocked to prevent harm to the participant; therefore, responses measured were precursors to self-injury. A multielement experimental design included four assessment conditions: social attention contingent on precursory behavior, attention contingent on behavior incompatible with precursory behavior, continuous attention and minimal attention. Highest rates of precursory behavior occurred during continuous attention and when incompatible behavior was reinforced. Social attention appeared to act as a discriminative stimulus for self-injurious behavior in this participant.

Lesch-Nyhan disease and the basal ganglia

The purpose of this review is to summarize emerging evidence that the neurobehavioral features of Lesch-Nyhan disease (LND), a developmental disorder caused by congenital deficiency of the purine salvage enzyme hypoxanthine-guanine phosphoribosyltransferase (HPRT), may be attributable to dysfunction of the basal ganglia. Affected individuals have severe motor disability described by prominent extrapyramidal features that are characteristic of dysfunction of the motor circuits of the basal ganglia. They also display disturbances of ocular motility, cognition, and behavioral control that may reflect disruption of other circuits of the basal ganglia. Though neuropathologic studies of autopsy specimens have revealed no obvious neuroanatomical abnormalities in LND, neurochemical studies have demonstrated 60-90% reductions in the dopamine content of the basal ganglia. In addition, recent PET studies have documented significant reductions in dopamine transporters and [18F]fluorodopa uptake in the basal ganglia. These findings support the proposal that many of the neurobehavioral features of LND might be related to dysfunction of the basal ganglia.

A review of behavioral treatments used for Lesch-Nyhan syndrome

Lesch-Nyhan syndrome is a genetic disorder resulting in hyperuricemia, choreoathetosis, mental retardation, and self-mutilation. The most salient feature of this disorder is the self-injurious behavior (SIB). Although the utility of behavioral interventions with SIB has been well documented, behavioral interventions with Lesch-Nyhan syndrome have been limited in number and long-term success. This article reviews the behavioral treatments that have been used in treating individuals with Lesch-Nyhan syndrome and discusses the strengths and weaknesses of these methods. Suggestions for future directions in the use of behavioral interventions for controlling SIB in Lesch-Nyhan syndrome are provided.

The treatment of severe self-injurious behavior by the systematic fading of restraints: effects on self-injury, self-restraint, adaptive behavior, and behavioral correlates of affect

Severe self-injurious behavior (SIB) in people with mental retardation is difficult to treat when dangerously frequent or intense responding rules out functional analysis and interventions that permit free responding. This situation is common when restrictive devices, such as straight arm splints, are used. In this study, the effects of introducing flexion into a straight-arm splint, on SIB, self-restraint, adaptive behavior, and behavioral correlates of affect were examined for three individuals with severe mental retardation. Using single-case design methodology, for two individuals self-injury was reduced to zero, while the overall level of restriction was also significantly reduced. From the observed behavioral correlates of affect, there was no evidence of an increase in negative affect with the introduction of the new splint and the fading procedure, but there was evidence of an increase in positive vocalizations. Engagement in activities and social contact were not affected by the introduction of the new splint. The reasons for a decrease in SIB with a corresponding decrease in restriction in the absence of any manipulation of contingencies for SIB are discussed, with particular reference to stimulus control.

Cognitive functioning in Lesch-Nyhan syndrome

The present study represents the first effort to assess systematically the cognitive functioning of a population of individuals with Lesch-Nyhan syndrome using standardized psychometric instruments. Seven residents from a special hospital setting participated. They ranged in age from 10 years 1 month to 22 years 3 months (mean 13 years 7 months). Using the Stanford-Binet Intelligence Scale: IV, scores in each of the four domains assessed by this battery (Verbal Reasoning, Abstract/Visual Reasoning, Quantitative and Short-Term Memory), as well as the general composite score, ranged from moderately mentally retarded to low average. Areas of weakness included attention, the manipulation of complex visual images, the comprehension of complex or lengthy speech, mathematical ability, and multi-step reasoning.

Self-injury in Lesch-Nyhan disease

Parents of 40 patients with Lesch-Nyhan disease completed a questionnaire detailing developmental history, life course, management, medication, factors influencing variability and topography of self-injury. Several conclusions were reached. Characteristics: Biting was the predominant form, perhaps only because of the difficulty of preventing it. There was considerable variability in self-injury which was strongly related to stress rather than to operant influences. Even though patients could not inhibit self-injury they could predict it and request restraints. Aggression against others was as prevalent as self-injury.

MANAGEMENT

Stress reduction, teeth extraction, and physical restraint were the most commonly used management techniques. Behavior modification was of limited efficacy. Benzodiazepines were the most commonly used medications for controlling self-injury.

OUTCOME

The severity of self-injury did not change over years. Age of onset was a predictor of outcome. The earlier the age of onset the worse the self-injury eventually became. The discussion describes research strategies, suggests dimensions along which self-injury can be classified, and highlights behavior not commonly described in patients with Lesch-Nyhan disease.

Cognitive abilities of patients with Lesch-Nyhan disease

Parents of 42 patients with Lesch-Nyhan disease completed a questionnaire systematizing caregiver observations of the subject's behavior during a wide variety of daily events. Responses were grouped in nine categories reflecting different aspects of cognitive skills. Only 1 boy appears to have any significant generalized cognitive impairment. The patients' memory for both recent and past events is excellent, their emotional life has a normal range of reactions and is appropriate; they have good concentration, are capable of abstract reasoning, have good self-awareness, and are highly social. However, they are behind in academic ability, with only 15% at grade level for math and reading. Implications for designing educational activities, parenting or caregiver strategies, and research methodology are discussed.

Effective behavioral treatment of self-biting by a child with Lesch-Nyhan syndrome

Behavior modification consisting of differential reinforcement of incompatible behavior and "punishment' was used for short periods at an early intervention center and was effective in eliminating self-biting of the arms, forearms and backs of the hands by a two-year-old with Lesch-Nyhan syndrome. No side-effects of the "punishment' component were observed. The effectiveness of the treatment was generalized to 3 1/2-hour sessions with his teacher at the early intervention center, and to the child's home. At six-month follow-up the teacher and parents indicated the continued absence of biting of the arms, forearms and back of the hands. The same treatment was applied to biting the fingers and the palms of the hands, without success.

Treatment of severe self-injurious and aggressive biting

The treatment of a 16-year-old severely mentally retarded and blind female client exhibiting severe biting of self and others consisted of the contingent application of an aversive gustatory stimulus (Tabasco Sauce), brief timeout, DRO, and contingent restraint against biting while in time-out. This is the first use of Tabasco as the aversive stimulus against biting. Deceleration of biting was rapid and maintained for 20 months after initiation of treatment.

The biochemical basis of the behavioral disorder in the Lesch-Nyhan syndrome

An inherited complete deficiency of hypoxanthine-guanine phosphoribosyltransferase in male children is associated with a severe neurological disorder characterized by chloroform and athetoid movements, hypertonicity, mental retardation, and self-injurious behavior. In the review that follows several possible mechanisms by which the enzyme defect may cause the CNS disorder are discussed. Current evidence suggests that the primary neural deficit in the Lesch-Nyhan syndrome is a deficiency of dopamine in the basal ganglia. It is argued that this neurochemical lesion results from a deficiency of purine nucleotides which impairs arborization of nigrostriatal neurons during perinatal development. Differences in the ontogenetic timing of the neurochemical lesion may be partly responsible for the different neurological symptoms displayed by persons afflicted with the Lesch-Nyhan and Parkinson's syndromes.

Treatment package to reduce SIB in a Lesch-Nyhan patient

Self-destructive behaviour in LNS children results in a tremendous burden to parents, teachers, staff members, and other responsible for their care. As constant vigilance is not always feasible, developing alternate methods of managing SIB becomes imperative. This report presents our efforts to improve the care of an LNS child and to ease the burden on staff members and parents by obtaining special devices (e.g. the custom-made mouthguard and the gloves) to prevent him from injuring himself. Others (e.g. Letts & Hobson, 1975) have likewise reported success in fabricating custom-designed chairs and devices in an effort to manage SIB in LNS children. Their devices were, however, more elaborate and much more expensive than the ones used in this report. The cost of obtaining a mouthguard similar to the one used with K. is estimated at between $20-$30 (US), while the gloves cost only $14.00. The major advantages of using such devices are that they safely allow employment of the extinction procedure along with allowing the child to participate more fully in activities of daily living. It is recognized that K. was in some ways an atypical Lesch-Nyhan child in that he possessed low normal receptive intelligence and scored fairly high (relative to most LNS children) on a test of verbal intelligence. His cognitive and verbal abilities made him a unique case in that he responded favourably to therapeutic instructions regarding relaxation and self-control tactics. The therapists were able to rely on K.'s verbalizations and feelings about his biting in structuring the treatment approach.(ABSTRACT TRUNCATED AT 250 WORDS)

Lesch-Nyhan disease: clinical experience with nineteen patients

The clinical phenotype in Lesch-Nyhan disease has been analyzed in 19 patients studied in hospital. In each case the diagnosis was made on the basis of inactivity of the enzyme hypoxanthine guanine phosphoribosyltransferase in erythrocyte lysates. All had hyperuricemia, and the presence of 'orange sand' in the diaper was a prominent early complaint. All had self-mutilative behavior, of which the most characteristic form was biting the fingers or lips. All had the neurological syndrome of spasticity and choreoathetoid involuntary movements. All but one had less-than-normal intelligence.

Problems in the behavioural treatment of self-injury in the Lesch-Nyhan syndrome

The results are described of a behavioural programme designed to modify self-injurious behaviour of a child with Lesch-Nyhan syndrome. The treatment combined extinction of the injurious behaviour and reinforcement of alternative behaviour, and was successful in the controlled hospital environment. However, an attempt to teach the parents to continue the treatment at home failed. The results are discussed in terms of the possible relationship between organic and environmental factors in maintaining the injurious behaviour, and the importance of analysing both the behaviour itself and the factors (including familial) maintaining it. It is suggested that parents should be advised about management of behavioural problems at an early age.