Mental Retardation
Mental Retardation: Excerpt from The 5-Minute Pediatric Consult
Rita Panoscha, MD
Mental Retardation - BASICS
Mental Retardation - description
- Mental retardation essentially means slow rate of learning or slow cognitive processing abilities. By definition, there are significant cognitive and adaptive delays 1st evident in childhood. Significant cognitive delays are defined as 2 standard deviations below the population mean on a standard cognitive or IQ test.
- Usually indicates an IQ score of <70–75
- Adaptive skills are the functional skills of everyday life, including communication, social skills, daily living/self-care skills, and the ability to safely move about the home and community.
- Mental retardation is typically subdivided into mild, moderate, severe, and profound categories, depending on the severity of the delays. A more recent definition by the American Association on Mental Retardation (AAMR) puts more emphasis on the level of functioning and the amount of support required by an individual.
- Children with behavioral problems may also be masking cognitive delays.
- Hearing impairment may present as a delay in development.
- Children with mild mental retardation may not be diagnosed as having a problem until they are having difficulties keeping up in elementary school.
Mental Retardation - general prevention
- There is no specific prevention, but prevention of some underlying causes may be possible.
- Immunization programs, early detection of metabolic disorders, and education programs for head injury/asphyxia prevention may be useful in some cases.
- Avoidance of alcohol and some drugs during pregnancy may also decrease some brain insults.
Mental Retardation - epidemiology
Found in both sexes and all racial and socioeconomic groups
Mental Retardation - prevalence
- Prevalence of mental retardation is generally listed as 2–3% of the population.
- Of the different subcategories of mental retardation, the mild form is the most prevalent, at 85% of those with mental retardation.
- Profound mental retardation is least prevalent, at ~1% of this group.
Mental Retardation - etiology
- The cause of the mental retardation is usually an insult to the brain or abnormal development of the CNS but is not evident in many cases. The following represent potential causes.
- Genetic/Familial/Metabolic:
- Fragile X syndrome
- Trisomy 21 (Down syndrome) and other chromosomal abnormalities
- Tuberous sclerosis
- Neurofibromatosis
- PKU (phenylketonuria)
- Other inborn errors of metabolism
- Nervous system anomalies:
- Hydrocephalus
- Lissencephaly
- Seizures
- Endocrinologic:
- Congenital hypothyroidism
- Infectious:
- Prenatal cytomegalovirus, rubella, toxoplasmosis, HIV
- Postnatal bacterial meningitis, neonatal herpes simplex
- Environmental toxins:
- Heavy-metal poisoning such as lead
- In utero drug or alcohol exposure, including fetal alcohol syndrome
- Traumatic:
- Closed-head trauma
- Asphyxia
Mental Retardation - associated conditions
- Associated findings are more common in the more severe forms of mental retardation.
- Mental retardation has many associated findings, including seizures, autism, cerebral palsy, communication disorders, failure to thrive, sensory impairments, and psychiatric disorders.
- Behavioral disorders can be seen, including attention deficit hyperactivity disorder, self-injurious and self-stimulating behaviors.
- Families often face additional stressors when caring for a child with mental retardation.
Mental Retardation - DIAGNOSIS
Mental Retardation - signs & symptoms
Dependent on etiology:
- Developmental delays
- Slow learning behavior
Mental Retardation - history
Complete information regarding the following:
- Pregnancy history:
- Maternal age and parity
- Maternal complications (including infections and exposures)
- Medications/Drugs used
- Tobacco or alcohol used, along with quantities
- Fetal activity
- Birth history:
- Gestational age
- Birth weight
- Route of delivery
- Maternal or fetal complications/distress
- Apgar scores
- General health:
- Significant illnesses, hospitalizations, or surgeries
- Accidents or injuries
- Hearing and vision status
- Medications used
- Known exposures to toxins
- Any new or unusual symptoms
- Developmental history:
- Current developmental achievement in each stream of development
- Age when developmental milestones were achieved
- Any loss of skills
- Where parents think their child is functioning developmentally
- Educational history:
- Type of schooling and services received, if any
- Any previous educational/developmental testing
- Behavioral history:
- Any perseverative or stereotypical behaviors
- Interaction skills
- Attention and activity levels
- Family history:
- Family members with developmental delays, neurologic disorders, syndromes, inherited disorders, or consanguinity
Mental Retardation - physical exam
A complete physical examination including growth parameters is needed looking for etiology. Key features to include are the following:
- Observation of interactions and behavior:
- Atypical behaviors and general impressions
- Head circumference:
- Skin examination:
- Major or minor dysmorphic features:
- Indication of a syndrome or anatomic malformation
- Neurologic examination:
- Assess for cranial nerve deficits, neuromuscular status, reflexes, balance and coordination, and any soft signs.
Mental Retardation - tests
- When developmental delays are present and mental retardation is suspected, more formal developmental screening or testing should be done.
- Possible tests for the pediatrician are the Denver-II Developmental Screening Test or the Cognitive Adaptive Test/Clinical Linguistic & Auditory Milestone (CAT/CLAMS).
- Diagnosis needs to be made based on standardized tests, usually done by a clinical psychologist. Such standardized testing might involve the Stanford Binet Intelligence Scale, the Wechsler Scales, and the Vineland Adaptive Behavior Scales.
Mental Retardation - lab
- There is no specific laboratory test battery for mental retardation. The testing needs to be tailored to the individual situation based on the history and physical examination. A high index of suspicion should be maintained for any associated findings and delays in the other streams of development. Listed below are some of the more common studies:
- Genetic testing:
- For any dysmorphic features, or a family history of delays or genetic disorder
- A karyotype and fragile X DNA should be considered, particularly for significant cognitive delays.
- Metabolic tests:
- Quantitative plasma amino acid, quantitative urine organic acid, lactate, pyruvate, or ammonia levels should be considered if there is any loss of skills or indication of a metabolic disorder.
- Additional metabolic tests may be indicated depending on symptoms.
- Thyroid function tests:
- Most infants will have had screening for hypothyroidism shortly after birth. This should be rechecked if symptoms indicate.
Mental Retardation - imaging
Head MRI:
- Consider for head abnormalities, significant neurologic findings, loss of skills, or for workup of a specific disorder such as trauma or leukodystrophy.
Mental Retardation - diag proced-surgery
- Audiologic testing:
- For any child with speech and language and/or cognitive delays
- EEG:
- An EEG should be considered if there is any concern about seizures.
Mental Retardation - differencial diagnosis
The differential can include several other developmental diagnoses, including the following:
- Borderline cognitive abilities
- Developmental language disorder
- Autism
- Learning disability
- Cerebral palsy
- Significant visual or hearing impairment
- Degenerative disorders
Mental Retardation - TREATMENT
Mental Retardation - general measures
- There is no specific cure for mental retardation. The ultimate goal of all therapies is to help the child reach his or her full potential.
- Therapy should consist of appropriate treatment for any underlying or associated medical condition.
- Early intervention and special education programs are available for an individualized education program based on the child’s needs and abilities.
- Behavior management programs or selected use of medications is available for patients with severe behavioral problems. The ultimate goal of all therapies is to help the child reach his or her full potential.
Mental Retardation - FOLLOW UP
Mental Retardation - disposition
Mental Retardation - issues for referral
- A referral to a clinical psychologist for the formal diagnosis
- Subspecialists:
- Referral to other medical specialists may also be indicated.
- These specialists may include developmental pediatrics, neurology, genetics, or ophthalmology.
Mental Retardation - prognosis
The prognosis for longevity varies with the associated findings and overall health, but individuals with mental retardation can live to adulthood and old age. An individual’s level of functioning is variable depending on the level of retardation, special individual skills, and family or community supports. In general, the following applies:
- Mild mental retardation (IQ 55–70): Formerly called educable. May be in school with extra help and may achieve roughly a 4th–6th grade level in reading and math. May be employed in an unskilled to semiskilled job. May live in a group home or independently. Some marry.
- Moderate mental retardation (IQ 40–54): May learn to recognize basic words and learn basic skills. May work in a sheltered workshop or with supported employment in an unskilled job. May live with family or in a group home doing much of their own care
- Severe mental retardation (IQ 25–39): May live with family, or in a group home or institution. Some may be in a sheltered workshop. May be able to do some daily self-care or chores with supervision
- Profound mental retardation (IQ <25): Live with family, in group home, or in institution. Usually require full-time care
Mental Retardation - patient monitoring
- Children with mental retardation will need regular pediatric preventative care in addition to management of any underlying medical conditions.
- Ongoing monitoring of the educational programs, to ensure that it is still meeting the child’s needs, is important.
- The family will also need ongoing counseling and support in dealing with a child having special needs.
Mental Retardation - bibliography
American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders. 4th ed., Text Revision, Washington, DC: American Psychiatric Association; 2000.- Batshaw ML. Mental retardation. Pediat Clin North Amer. 1993;40:507–521.
- Battaglia A. Neuroimaging studies in the evaluation of developmental delay/mental retardation. Am J Med Genet. 2003;117C:25–30.
- Battaglia A, Carey JC. Diagnostic evaluation of developmental delay/mental retardation: An overview. Am J Med Genet. 2003;117C:3–14.
- Gilbride KE. Developmental testing. Pediatr Rev. 1995;16:338–345.
- Johnson CP, Walker WO. Mental retardation: Management and prognosis. Pediatr Rev. 2006;27(7):249–255.
- Moeschler JB, Shevell M, Committee on Genetics. Clinical genetic evaluation of the child with mental retardation or developmental delays. Pediatrics. 2006;117:2304–2316.
- Palmer FB, Capute AJ. Mental retardation. Pediatr Rev. 1994;15:473–479.
- Walker WO, Johnson CP. Mental retardation: Overview and diagnosis. Pediatr Rev. 2006;27(6):204–211.
Mental Retardation - CODES
Mental Retardation - icd9
- 317 Mild mental retardation
- 318.0 Moderate mental retardation
- 318.1 Severe mental retardation
- 318.2 Profound mental retardation
- 319 Unspecified mental retardation
Mental Retardation - FAQ
- Q: Will my child be “normal” by adulthood?
- A: Generally, mental retardation is considered a life-long condition. Some individuals, usually with the milder form of mental retardation, can function well in the community, especially when given added supports.
- Q: Can my child learn?
- A: Except for the most severe forms of mental retardation, children do learn. This learning may not be as rapid or as extensive as that of a typically developing child.
- Q: But my child looks fine and has had appropriate motor development. How can he/she be mentally retarded?
- A: Mental retardation is a slowed rate of cognitive development. Many children with mental retardation do not have obvious dysmorphic features. Other streams of development, such as gross motor skills, may be reached on time or nearly so, yet the cognitive developmental streams can be significantly delayed.
>>
Book Source Details
- Book Title: The 5-Minute Pediatric Consult
- Author(s): M. William Schwartz MD; et al.
- Year of Publication: 2008
- Copyright Details: The 5-Minute Pediatric Consult, Copyright © 2008 Lippincott Williams & Wilkins.
More About Coffin-Lowry syndrome
More Medical Textbooks Online about Coffin-Lowry syndrome
Review other book chapters online related to Coffin-Lowry syndrome:
Copyright notice for book excerpts: Copyright © 2008 Lippincott Williams & Wilkins. All rights reserved.
|
|
More About This Book:
Title: The 5-Minute Pediatric Consult
Authors: M. William Schwartz MD; et al.
Publisher: Lippincott Williams & Wilkins
Copyright: 2008
ISBN: 0-7817-7577-9
|
|
» Next page:
Surveys relating to Coffin-Lowry syndrome
Rate This Website
What do you think about the features of this website?
Take our user survey and have your say:
Website User Survey
Medical Tools & Articles:
Next articles:
Tools & Services:
Medical Articles:
Forums & Message Boards
- Ask or answer a question at the Boards:
