pervasive developmental disorder

More about Pervasive Developmental Disorders: Causes and symptoms Diagnosis Treatment Prognosis Prevention Resources

Definition

Pervasive developmental disorders include five different conditions: Asperger's syndrome, autistic disorder, childhood disintegrative disorder (CDD), pervasive developmental disorder not otherwise specified (PDDNOS), and Rett's syndrome. They are grouped together because of the similarities between them. The three most common shared problems involve communication skills, motor skills, and social skills. Since there are no clear diagnostic boundaries separating these conditions it is sometimes difficult to distinguish one from the other for diagnostic purposes.

Asperger's syndrome, autistic disorder, and childhood disintegrative disorder are four to five times more common in boys, and Rett's syndrome has been diagnosed primarily in girls. All of these disorders are rare.

Description

Asperger's syndrome

Children afflicted with Asperger's syndrome exhibit difficulties in social relationships and communication. They are reluctant to make eye contact, do not respond to social or emotional contacts, do not initiate play activities with peers, and do not give or receive attention or affection. To receive this diagnosis the individual must demonstrate normal development of language, thinking and coping skills. Due to an impaired coordination of muscle movements, they appear to be clumsy. They usually become deeply involved in a very few interests which tend to occupy most of their time and attention.

Autistic disorder

Autistic disorder is frequently evident within the first year of life, and must be diagnosed before age three. It is associated with moderate mental retardation in three out of four cases. These children do not want to be held, rocked, cuddled or played with. They are unresponsive to affection, show no interest in peers or adults and have few interests. Other traits include avoidance of eye contact, an expressionless face and the use of gestures to express needs. Their actions are repetitive, routine and restricted. Rocking, hand and arm flapping, unusual hand and finger movements, and attachment to objects rather than pets and people are common. Speech, play, and other behaviors are repetitive and without imagination. They tend to be overactive, aggressive, and self-injurious. They are often highly sensitive to touch, noise, and smells and do not like changes in routine.

Childhood disintegrative disorder

Childhood disintegrative disorder is also called Heller's disease and most often develops between two and ten years of age. Children with CDD develop normally until two to three years of age and then begin to disintegrate rapidly. Signs and symptoms include deterioration of the ability to use and understand language to the point where they are unable to carry on a conversation. This is accompanied by the loss of control of the bladder and bowels. Any interest or ability to play and engage in social activities is lost. The behaviors are nearly identical with those that are characteristic of autistic disorder. However, childhood disintegrative disorder becomes evident later in life and results in developmental regression, or loss of previously attained skills, whereas autistic disorder can be detected as early as the first month of life and results in a failure to progress.

Pervasive developmental disorder not otherwise specified

The term pervasive developmental disorder not otherwise specified (PDDNOS) is also referred to as atypical personality development, atypical PDD, or atypical autism. Individuals with this disorder share some of the same signs and symptoms of autism or other conditions under the category of pervasive developmental disorders, but do not meet all of the criteria for diagnosis for any of the four syndromes included in this group of diseases. Because the children diagnosed with PDDNOS do not all exhibit the same combination of characteristics, it is difficult to do research on this disorder, but the limited evidence available suggests that patients are seen by medical professionals later in life than is the case for autistic children, and they are less likely to have intellectual deficits.

Rett's syndrome

Rett's syndrome was first described in 1966 and is found almost exclusively in girls. It is a disease in which cells in the brain experience difficulty in communicating with each other. At the same time the growth of the head falls behind the growth of the body so that these children are usually mentally retarded. These conditions are accompanied by deficits in movement (motor) skills and a loss of interest in social activities.

The course of the illness has been divided into four stages. In stage one the child develops normally for six to 18 months. In stage two, development slows down and stops. Stage three is characterized by a loss of the speech and motor skills already acquired. Typically this happens between nine months and three years of age. Stage four begins with a return to learning which will continue across the lifespan, but at a very slow rate. Problems with coordination and walking are likely to continue and even worsen. Other conditions that can occur with Rett's syndrome are convulsions, constipation, breathing problems, impaired circulation in the feet and legs, and difficulty chewing or swallowing.

— Donald G. Barstow, RN

---

n. (Abbr. PDD)
Any of several disorders, such as autism and Asperger's syndrome, characterized by severe deficits in many areas of development, including social interaction and communication, or by the presence of repetitive, stereotyped behaviors. Such disorders are usually evident in the first years of life and are often associated with some degree of mental retardation.

(Professional Disk for Data) A 5.25" rewritable optical disc technology from Sony Electronics Inc. www.sonyburners.com) that also supports write-once (WORM) media. Using blue laser optics and phase change recording, 23GB drives and cartridges were introduced in 2004. See UDO.

Download Computer Desktop Encyclopedia to your iPhone/iTouch

n

A disorder of behavioral and sensory impairment which generally appears during infancy or early childhood and continues to affect the individual’s ability to communicate and interact with others throughout his or her life. See also autism.

Definition

Pervasive developmental disorders are a group of neurological disorders that include autistic disorder (autism), Asperger's syndrome, childhood disintegrative disorder, Rett's syndrome, and pervasive developmental disorder not otherwise specified (PDDNOS). These disorders are characterized by delayed development in functional, socialization, and communication skills.

Description

The term pervasive developmental disorders was first used in the 1980s to describe a class of neurological disorders that involved impaired social and communication skills and repetitive behaviors.

Due to difficulties in accurately describing these disorders using the term pervasive developmental disorders, some neurological and psychiatric specialists have proposed new terminology to describe this class of disorders, including autistic spectrum disorders and multi-system neurological disorders.

Asperger's Syndrome

Asperger's syndrome is characterized by difficulties with social relationships and skills and with poor coordination and restricted range of interests. Children with Asperger's syndrome generally have a normal to above average intelligence level and adequate knowledge of vocabulary and grammar but poor concentration and ability to understand language subtleties, such as humor. Asperger's syndrome is often incorrectly referred to as "high-functioning autism."

Autistic Disorder

Autistic disorder, also referred to as autism, is characterized by moderate to severe communication, socialization, and behavioral problems, and in some children, mental retardation.

Childhood Disintegrative Disorder

Childhood disintegrative disorder is extremely rare, relative to the other pervasive developmental disorders. Children with this disorder develop normally until at least two years of age, after which an obvious regression in multiple functional skills occurs, including bladder and bowel control, ability to move, and language skills.

Pervasive Developmental Disorder Not Otherwise Specified (Pddnos)

Children are diagnosed with PDDNOS if their symptoms do not fit any of the other four types and/or they do not have the degree of impairment of the other four types. PDDNOS involves developmental impairments, such as communication and social skills, and repetitive behaviors that cannot be attributed to a specific developmental disorder or personality disorder. Usually, children with PDDNOS do not exhibit symptoms until age three or four.

Rett's Syndrome

Rett's syndrome occurs primarily in female children and is characterized by normal development for the first six to 18 months, followed by a noticeable change in behavior and loss of some abilities, especially motor skills. As the child ages, significant loss of speech, hand movement, and reasoning develops. Children with Rett's syndrome usually repeat certain movements and gestures, in particular, hand wringing or hand washing. Rett's syndrome is the rarest of the pervasive developmental disorders.

Demographics

About one in 1,000 children born in the United States is diagnosed with autistic disorder, and it is four to five times more common in boys. Rett's syndrome has been diagnosed primarily in girls. Although autism is the most well-known of these disorders, PDDNOS is at least twice as common in children.

Causes and Symptoms

As of 2004, the causes of these disorders were unknown. While genetics is believed to play a primary role, some children in families with a history of pervasive developmental disorders do not have a disorder. Medical researchers believe that genetic susceptibility plus additional factors contribute to the development of one of these disorders. Factors under investigation as a cause of these disorders include immune system problems, allergies, drugs, environmental pollution, and infections. Autopsy studies of individuals with pervasive developmental disorders have shown that brain cell structure is different, particularly in the brain stem area. In addition, because many individuals with pervasive developmental disorders are also affected by seizures, "electrical miswiring" of the brain may also contribute to these disorders. Researchers have used magnetic resonance imaging (MRI) and positron emission tomography (PET) to find subtle differences in the brain structure and function of children with these disorders.

Symptoms of pervasive developmental disorders may be visible as early as infancy; however, the typical age of onset is age three. Although each of the five types has some distinctive symptoms, in general, early symptoms of a pervasive developmental disorder include the following:

.

• impaired language skills
• difficulties relating to people, objects, or activities
• unusual play
• repetitive body movements or behavior patterns
• difficulties handling changes in routine or surroundings
• unusual responses to sensory stimuli, like loud noises and lights

When to Call the Doctor

Parents should see a physician as soon as they notice developmental problems or delays in their infant or child.

Diagnosis

Pervasive developmental disorders are diagnosed using the Diagnostic and Statistical Manual of Mental Disorders (DSM), which provides criteria for physicians to diagnose the specific type. Diagnosis of a pervasive developmental disorder is difficult because there is no specific medical test, like a blood test or imaging test that can confirm the diagnosis. Some physicians may hesitate to diagnose very young children with a specific type of pervasive developmental disorder.

Diagnosis of these disorders usually requires consultation and assessment by a specialist in childhood developmental disorders, such as a child psychiatrist, pediatric neurologist, neuropsychologist, or developmental child psychologist. These specialists evaluate laboratory medical tests, neurological tests, and psychological tests; interview parents and children; and observe and assess behaviors. Educational skill testing, communication assessment, and motor skill assessment may also be conducted. Medical tests that may be performed to rule out other medical conditions include electroencephalography, MRI, and blood tests.

Once a pervasive developmental disorder is diagnosed, the diagnosis must be narrowed to one of the five types, which is achieved by using pre-established DSM criteria that outline the key differences among the types. For example, for childhood disintegrative disorder to be diagnosed, symptoms must be preceded by at least two years of normal development and onset of decline and regression must occur prior to age 10 years.

Treatment

As of 2004, no cure existed for these disorders, and no specific therapy works for all individuals. Treatment depends on the severity of the disorder and consists of specialized therapy, special education, and medication to address specific behavioral problems. Medications that may be prescribed to treat specific symptoms include anti-depressants, anti-anxiety medications, anti-spasmodic and anti-seizure medications, and stimulants. Therapeutic interventions include applied behavior analysis (the Lovaas method), auditory integration training, behavior modification programs, play therapy, occupational and physical therapy, animal-assisted therapy, art/music/dance therapy, sensory integration, and speech therapy.

Alternative Treatment

Alternative treatments for pervasive developmental disorders focus on nutrition. Some evidence has shown that vitamin therapy with vitamin B6 and magnesium supplementation can help children with autism and PDDNOS. Because some children with pervasive developmental disorders have food sensitivities or food allergies, allergy testing and subsequent dietary modification may help. In food-allergic children, certain foods have been shown to increase hyperactivity and autistic behavior. Anti-yeast therapy has also been proposed because children with autism and PDDNOS sometimes have higher yeast levels in their bodies. Administering anti-yeast medications has decreased negative behaviors in some children. Before parents turn to alternative therapy, they should consult a physician to make sure it does not interfere or interact with any other medications.

Prognosis

Pervasive developmental disorders are not life-threatening and do not affect normal life expectancy. Prognosis depends on the severity and type of disorder and the effectiveness of early interventions. Early intervention with specialized educational and behavioral support programs improves the quality of life and level of functioning of children with these disorders. However, because of their impaired communication and social skills, about 70 percent of individuals with a pervasive developmental disorder are never able to live on their own.

Prevention

Pervasive developmental disorders are caused by a complex interaction of genetics, neurological factors, and environmental factors. As of 2004, there was no genetic test to detect these disorders, and there is no way to prevent their development.

Parental Concerns

The majority of children with a pervasive developmental disorder will require special education services. By law, public schools must evaluate children at no cost and provide special education services to eligible children with disabilities. Some private or alternative schools may be dedicated to serving children with such disorders and offer more comprehensive education and therapeutic options, but at an additional cost to parents.

Parenting children with pervasive developmental disorders is difficult and emotionally demanding. Parents and families can benefit from joining a support group. Benefits of parent support groups include information sharing, emotional support, and educational assistance.

Resources

Books

Bashe, P. R., and B. L. Kirby. The Oasis Guide to Asperger Syndrome. Oakland, CA: PAR Bookworks, 2001.

Myles, B. S., and D. Adreon. Asperger Syndrome andAdolescence: Practical Solutions for School Success. Shawnee Mission, KS: Autism Asperger Publishing Company, 2001.

Stockman, Ida J. Movement and Action in Learning andDevelopment: Clinical Implications for Pervasive Developmental Disorders. Kent, UK: Elsevier Science and Technology Books, 2004.

Volkmar, Fred R., et al. Handbook of Autism and PervasiveDevelopmental Disorders. New York: John Wiley & Sons, 2005.

Periodicals

Muhle, R., et al. "The Genetics of Autism." Pediatrics 113 (May 2004): 472–86.

Szatmari, P., et al. "Two-Year Outcome of Preschool Children with Autism or Asperger's Syndrome." American Journal of Psychiatry 157 (December 2000): 1980–87.

Organizations

Asperger Syndrome Education Network. Web site: www.aspennj.org/.

Developmental Delay Resources. Web site: www.devdelay.org/.

National Alliance for Autism Research. 99 Wall Street, Research Park, Princeton, NJ 08540. Web site: www.naar.org/naar.asp.

National Institute of Child Health and Human Development. Bldg 31, Room 2A32, MSC 2425, 31 Center Drive, Bethesda, MD 20892–2425. Web site: www.nichd.nih.gov/default.htm.

Web Sites

"NINDS Pervasive Developmental Disorders Information Page." National Institute of Neurological Disorders and Stroke, July 2003. Available online at www.ninds.nih.gov/health_and_medical/disorders/pdd.htm (accessed October 27, 2004).

Sanders, Lisamarie. "Pervasive Developmental Disorders: What Parents Need to Know", 2004. Available online at (accessed October 27, 2004).

[Article by: Jennifer E. Sisk, MA]

---

This entry is from Wikipedia, the leading user-contributed encyclopedia. It may not have been reviewed by professional editors (see full disclaimer)