Intellectual impairment Flashcards

Question

A. Adrenoleukodystrophy B. Rett syndrome C. Acquired immune deficiency syndrome (AIDS) D. Rubella E. Cytomegalic inclusion disease/cytomegalic virus (CMV) F. Toxoplasmosis An X-linked mental retardation syndrome that is degenerative and affects only females View Answer37.23

Answer 1

A Adrenoleukodystrophy is an X-linked recessive disorder characterized by diffuse demyelination of the cerebral cortex, leading to visual and intellectual impairment, seizures, and spasticity accompanied by adrenocortical insufficiency. The onset of the disease typically occurs between the ages of 3 and 10 years, and the course is usually rapidly progressive and fatal.

Answer 2

C Lesch-Nyhan syndrome, a rare X-linked recessive disorder that involves an inability to metabolize uric acid, causes ataxia, chorea, renal failure, and gout, as well as striking self-mutilatory (particularly self-biting) behavior and mild to moderate mental retardation

Answer 3

E Neurofibromatosis (type 1) is an autosomal dominant disorder caused by a defect in chromosome 17, with a variety of clinical manifestations, including cutaneous neurofibromas, cafe-au-lait spots, short stature, macrocephaly, Lisch nodules, and bony dysplasias. Ten percent of affected individuals have moderate to profound mental retardation, and half manifest speech and language difficulties. Distractibility, impulsivity, anxiety, and depression are also prominent features.

Answer 4

E. One of the most common causes of death in Down’s syndrome is congenital heart disease. Common phenotypic features seen in children with Down’s syndrome include brachycephaly, broad hands, single palmar crease, epicanthal folds, clinodactyly of fi fth fi nger, fl at nasal bridge, and wide gap between fi rst and second toes, hypotonia with lax ligaments, short stature, and mental retardation. In addition, children may have congenital heart defects such as ventricular septal defect, duodenal atresia at birth, and increased incidence of leukaemia in childhood. Atlantoaxial subluxation may occur in children with Down’s syndrome, leading to spinal cord compression. The signs and symptoms of hypothyroidism can develop slowly over time and can be diffi cult to discriminate from those of Down’s syndrome itself. No differences have been found in terms of age of onset of the physical features of puberty in adolescent girls and boys with Down’s syndrome compared with general population trends. In men, reproductive capacity appears to be diminished, but women with Down’s syndrome are able to bear children

Answer 5

A. Children with Down’s syndrome are known to be gentle, mild mannered, and easygoing. It is reported that emotional and behavioural problems are less frequent than other forms of learning disabilities. Medical causes must be ruled out before considering a de novo psychiatric explanation for behavioural and emotional problems. The dual diagnoses of Down’s syndrome and autism has been recognized for some time, with recent reports quoting 7% of Down’s syndrome children having autism. Puri et al. (2001) showed in a study of 68 adults with Down’s syndrome that individuals aged over 45 with a history of seizures were signifi cantly more likely to develop Alzheimer’s dementia; nearly 84% of demented individuals with Down’s syndrome developed seizures. This is far higher than the rate of seizures found in Alzheimer’s dementia without Down’s syndrome (10%) and Down’s syndrome without dementia (8%). Early-onset seizures in Down’s syndrome seem to be unrelated to Alzheimer’s type of pathology

Answer 6

A. EO Lewis suggested the distinction between subcultural learning disability and biological learning disability in 1933. ‘Subcultural mental handicap’ refers to the lower extreme variant of IQ distribution seen in the population. The biological or pathological type is seen to be evenly distributed across all social classes, whereas the subcultural type is often seen in social class V and associated with mild rather than profound disability. Kraeplin is associated with dementia praecox, and French psychiatrist Benoit Morel is associated with the theory of degeneration in schizophrenia. Kanner is associated with infantile autism.

Answer 7

E. The diagnostic criteria for foetal alcohol syndrome includes confirmed maternal alcohol exposure in addition to evidence of characteristic facial anomalies such as short palpebral fissures and abnormalities in the premaxillary zone, including flat upper lip, cleft palate, flattened philtrum, and flat midface. Evidence of growth retardation includes low birthweight for gestational age or decelerating weight gain over time not due to undernutrition. Features suggestive of neurodevelopmental abnormalities such as decreased cranial size at birth, structural brain abnormalities (e.g. microcephaly, partial or complete agenesis of the corpus callosum, cerebellar hypoplasia), and neurological signs (impaired fi ne motor skills, neurosensory hearing loss, poor tandem gait, poor eye–hand coordination) are also included in the diagnostic criteria. Congenital cataract is not suggestive of foetal alcohol syndrome; in infants with cataract, other explanations for developmental problems such as toxoplasmosis, congenital rubella, or metabolic syndromes must be sought.

Answer 8

C. Subcultural learning disability refers to the lower extreme variant of IQ distribution seen in the population and it often seen in social class V and associated with mild rather than profound disability. Many family members of individuals with subcultural learning disability may also have borderline IQ, probably due to the effects of shared environment and social infl uences. In contrast, the biological or pathological type is seen to be evenly distributed across all social classes. Dysmophic features are more likely to be seen in those with a biological cause of learning disability with syndromic presentation being noted. Subcultural learning disability suggests the concept of a psychosocial causation (e.g. physical and emotional neglect). This is controversial.

Answer 9

C. Smith–Magenis syndrome has a prevalence of 1: 500 000. It is caused by a microdeletion on the short arm of chromosome 17p11·2. The degree of intellectual impairment is usually variable. The phenotype includes bradydactyly, a broad, fl at face, hoarse voice, and a characteristic fl eshy upper lip, although these features may be very subtle. Prominent autistic features, hyperactivity (in 75%), inattention, and self-injury (in 70%) such as head banging, nail pulling, and hand biting, are seen. Nocturnal and diurnal enuresis may also be present. Sleep is characterized by reduced or absent REM phase. Trisomy 21 refers to Down’s syndrome. 7q11 deletion in the elastin gene can result in Williams syndrome, which is characterized by hyperactivity, ‘cocktail party speech’, and supravalvular aortic stenosis. Hypoxanthine guanine phosphoribosyltransferase defi ciency can result in Lesch Nyhan syndrome with severe self-mutilation, aggression, and hyperuricaemia. Trisomy 13 syndrome is also known as Patau’s syndrome and can be of three types: full trisomy, mosaic pattern type, and translocation type. All survivors have profound mental retardation.

Answer 10

D. Autism is a disorder with lifelong disability. About 70% of autistic individuals have an IQ in the learning disability range. In autism, IQ has been shown to be the most powerful predictor of outcome. A distinctive cognitive profi le characterized by strong visuospatial skills and poor abstract ability has been noted. A small proportion of autistic children may have islets of special abilities and are dubbed as ‘autistic savants’. The presence of communicative speech by the age of 5 years is another important predictor of positive outcome.

Answer 11

D. In a sample of more than 2500 boys born in 1981, details of bullying and victimization were gathered when the boys were 8 years old. Between the ages of 18 and 23, information about psychiatric disorders was collected from a registry. The boys could be classifi ed into those who bully others, those who are frequently victimized, and those who bully others and are victimized frequently. Frequent bullying-only status predicted antisocial personality and substance abuse; frequent victimization-only status predicted anxiety disorder, whereas frequent bully– victim status predicted antisocial personality and anxiety disorder. Frequent bully–victims were at particular risk of adverse long-term outcomes compared with either pure bullies or pure victims.

Answer 12

B. Fragile X syndrome is the most common known inherited cause of learning disability. It affects 1:3600 boys and 1:6000 girls. Thirty per cent of individuals affected by fragile X have autistic features. Nearly 20% have epilepsy too. 1 in 300 women and 1 in 800 men are carriers of fragile X mutation. Although Down’s syndrome is a more common cause of learning disability, it is mostly sporadic and not inherited in the strict sense.

Answer 13

C. The point prevalence of schizophrenia is estimated to be between 3% and 4% in the learning-disabled population compared with 1% in the general population. Schizophrenia cannot be reliably diagnosed below an IQ of approximately 45. Often in clinical practice, if there is evidence of delusions or hallucinations in those with profound learning disability, a diagnosis of psychosis not otherwise specifi ed is used. Despite this the rate of schizophrenia is signifi cantly higher among the population with learning disability. This increase is seen despite the overall rate of psychiatric illness among adults with mild to moderate learning disability being similar to that in the general adult population without learning disability. The reason for this increased comorbidity is unclear, and common underlying brain damage that could cause both learning disability and schizophrenia cannot be ruled out.

Answer 14

B. Homocystinuria is a metabolic disorder characterized by an increased blood and urine concentration of amino acid homocysteine. Clinical features resemble Marfan syndrome; patients have ectopia lentis, chest and spinal deformities similar to Marfan syndrome. But changes in hair colour, osteoporosis, arterial and venous thrombosis, and learning disabilities are generally absent in patients with Marfan syndrome

Answer 15

C. In the past, learning disability has been a cause for social rejection, with prejudiced labels such as ‘degeneracy’ associated with it. The so-called degenerates were isolated from the community, leading to the establishment of large mental institutions. The principle of normalization is seen by many as a reaction to the dehumanizing policies of the past. Normalization promotes independence and autonomy while making it possible for people with learning disabilities to have an ordinary life with the same choices and opportunities as everyone else. This shifts the focus from ‘disability’ to ‘differences in ability’.

Answer 16

D. Nearly 85% of those with learning disability have an IQ in the range 50–70 (mild learning disability). Of the rest, nearly 10% have moderate learning disability with an IQ in the range 35–50 and around 5% have an IQ in the severe/profound learning disability range (less than 35).

Answer 17

D. Major epidemiological work in child psychiatry started with the Isle of Wight surveys between 1964 and 1974. The Isle of Wight surveys had a two-phase design, with a systematic questionnaire screening a large sample, followed by in-depth assessments of a sub-sample selected according to the results of screening. Multiple informants were used in both phases. All 9- to 11-year-old children attending state schools on the island were included in the primary survey. A 4-year follow-up was carried out for children identifi ed with psychiatric problems when they were approximately 14 years old.

Answer 18

C. Numerous cross-sectional epidemiological surveys have confi rmed that psychopathology in young people is common, with most studies estimating the prevalence to be between 10% and 20%. In a study that included more than 10 000 children, overall rates of psychiatric disorders in 5- to 15-year-old children in UK was estimated to be around 9.5%. A review of 49 surveys worldwide indicated an average point prevalence of 12.9% for psychiatric disorders in children. Emotional disturbances and behavioural disorders are equally common. Only a small proportion – between 10% and 30% – of children with a psychiatric disorder make contact with specialist mental health services.

Answer 19

D. Pervasive developmental disorders such as autism and Asperger’s syndrome are more common in boys. Attention defi cit hyperactivity disorder, tic disorders, oppositional defi ance, and conduct disorders are also seen more often in boys than in girls. The rate of depression seems equal between both sexes before puberty. School refusal and selective mutism are also equally common in both boys and girls. Depression after puberty, specifi c phobia, eating disorders, and enuresis in daytime are more common in girls. Nocturnal enuresis in older children is more prevalent in boys.

Answer 20

A. Conduct disorders are four times more common in boys than in girls according to the Isle of Wight study. Girls are more prone to use verbal and relational violence, such as exclusion from groups and character defamation, than the physical attacks seen in boys. Consequently, girls are violent in a way that can be diffi cult to document and to describe as conduct disorder symptoms; this may be a reason for under-diagnosis of conduct issues in girls.

Answer 21

E. The core features of reactive attachment disorder (RAD) are preserved across both diagnostic nosologies, ICD and DSM. But the focus on subtypes and emphasis on the pathogenic nature of care giving are different. The DSM-IV includes inhibited and disinhibited types of RAD. In ICD-10, the term reactive attachment disorder stands for inhibited type, while disinhibited attachment disorder is separately defi ned. Both ICD and DSM endorse problems of social relatedness in RAD. Age of onset criteria (before 5 years) and exclusion of pervasive developmental disorders are common for both nosologies. In addition, DSM-IV also requires the presence of a known history of grossly pathogenic care, suggesting a causal link. Children with the disinhibited subtype may appear indiscriminately social.

Answer 22

A. The term ‘frozen watchfulness’ describes an alertness or even hypervigilance that is maintained despite an overall inhibition of motor activity that may include mutism. Reactive attachment disorder (RAD) is associated with markedly disturbed and developmentally inappropriate social relatedness beginning before age 5 years. It commonly presents as persistent failure to initiate or respond to most social interactions. The responses can be excessively inhibited, hypervigilant, or highly ambivalent and contradictory. This is associated with avoidance of resistance to comforting or exhibiting a frozen watchfulness. This type of RAD is called the inhibited type. In disinhibited type, diffuse attachments manifested by indiscriminate sociability with marked inability to exhibit appropriately selective attachments are seen. This frozen watchfulness is different from aloofness seen in autism or dissociative features seen in PTSD. Frozen watchfulness is also seen in young victims of physical abuse.

Answer 23

C. According to current classifi catory systems, a learning disorder such as specifi c reading disorder can be diagnosed when the child achieves substantially lower than expected scores on individually administered, standardized tests of components of learning (reading, mathematics, or written expression) for a given age, schooling, and level of intelligence. Thus an explicit reference to psychometric assessments is made when diagnosing learning disorders. But a specifi c guideline as to the statistical meaning of being substantially below the expected norm is not clearly delineated in DSM IV. Nevertheless, ICD-10 states a score that is at least 2 standard errors of prediction below the expected value as diagnostic criteria for specifi c developmental disorders of scholastic skills.