DIAGNOSIS CHECKLIST
for Mental retardation

Why: mental retardation is reduced mental ability or intelligence. It is otherwise known as intellectual disability. It is defined as significantly sub-average general intellectual functioning existing concurrently with difficulties with functioning in everyday life. The disability must be manifested during the developmental period and thus excludes disabilities that result from brain damage occurring in adult life. Examples include fragile X syndrome, tuberous sclerosis, Down syndrome, trisomy 18, agenesis of the corpus callosum, cerebral palsy, Chiari malformation, fetal alcohol syndrome, hydrocephalus, Rett's syndrome, Soto's syndrome, microcephaly, autism, Duchenne muscular dystrophy and many other childhood syndromes.

Why: Children with mental retardation may present in 4 different ways. They may be diagnosed in the newborn period due to recognizable malformations which are usually associated with mental retardation such as Down syndrome. They may be diagnosed due to developmental delay. They may be diagnosed as a result of surveillance of infants at increased risk of developmental problems such as very low birth weight. They may be diagnosed with feeding or behavioral problems which on investigation are found to be associated with mental retardation.

Why: may detect prenatal infections, prenatal drugs and toxins, birth trauma, neonatal infection as a possible cause of mental retardation.

Why: must make allowance for prematurity i.e. if birth was at 32 weeks gestation, 8 weeks should be subtracted from the chronological age when assessing development, so that milestones would be expected to be reached 2 months later than a baby born at full term.

Why: e.g. any abnormality either structural or functional, identified at any age, but that began before birth such as anencephaly, phenylketonuria, muscular dystrophy, fetal alcohol syndrome, Down syndrome, hypothyroidism.

Why: e.g. smiling, able to remain in sitting position unsupported, crawled, walked.

Why: assesses expressive language.

Why: assesses receptive language. Receptive language is usually well in advance of expressive language.

Why: the parent is usually the first to suspect a hearing problem.

Why: may also affect development. Determine if home environment is appropriately stimulating to enable good language development and presents opportunities for a wide variety of play experience.

Why: e.g. developmental delay, genetic disorders.

Why: to assess chance of fetal alcohol syndrome.

Why: e.g. lead poisoning may cause mental retardation.

Why: e.g. poor eye contact, aloneness, difficulties relating to peers. Most children with autism also have an intellectual disability.

Why: e.g. if not walking by 18 months consider Duchenne muscular dystrophy. Of boys with Duchenne muscular dystrophy 10-15% have an intellectual disability.

Why: would suggest phenylketonuria.

Why: e.g. mental retardation, wide bulbous nose, low nasal bridge, moderate excess hairiness, finger and nail abnormalities (especially the 5th finger) and large ears. The full syndrome occurs only in males.

Why: e.g. mental retardation, flat facial profile, excess neck skin, small low set ears, reduced tone of the muscles of the limbs, round head, protruding tongue, short broad hands, incurving 5th digits. Down syndrome is the most common abnormality associated with intellectual disability. The spectrum of intellectual disability varies from mild to profound.

Why: e.g. mental retardation, shy personality, long face, high forehead, large jaw, long ears, over flexible joints, large testicles. It is the second most common cause of intellectual disability (after Down syndrome).

Why: e.g. brown skin streaks, mental retardation, disturbed dentition, eye defects, ear deformities.

Why: e.g. principle impairment is with social communication. Features include language delay with minimal use of speech and echolalia (involuntary repetition of a word or sentence just spoken by another person), poor eye contact, aloneness, difficulties in relating to peers, unusual preoccupation or stereotypical behaviors such as postural mannerisms. Most children with autism have an intellectual disability.

Why: e.g. occurs only in males, 10-15% of boys will have an intellectual disability, delayed motor development with 50% not walking before 18 months of age, abnormal gait including toe walking, the inability to run normally, difficulty in climbing and rising from sitting or lying position, frequent falls.