Multiplex developmental disorder (MCDD), also known as multiple-complex developmental disorder, is a potential subgroup of pervasive developmental disorder, not otherwise specified (PDD-NOS). When a child does not display the symptoms necessary for a classic autism or Asperger’s syndrome diagnosis (the two opposite ends of the spectrum), he is generally given the label of PDD-NOS.
Currently MCDD fits into a research category only. Since it is not yet found in The Diagnostic and Statistical Manual of Mental Disorders (DSM) used in the U.S. for diagnosis and statistics of mental disorders, or the International Statistical Classification of Diseases and Related Health Problems (ICD-10) managed by the World Health Organization, there is no specific treatment or education plan given in connection with a diagnosis.
MCDD Subtype: Emotional Instability and Disordered Thought
MCDD emerged as a possible future subtype after a large number of pre-school children showed signs of both autism spectrum disorders and the emotional instability and disordered thought of schizophrenic behavior. Unlike schizophrenia, however, the subtype typically manifests early – when a child is about 12- to 18-months old – and then continues throughout life.
Observable behaviors for diagnosis fall into three basic categories. To be diagnosed, a child must display symptoms from each of the following three categories.
Social Behavior Problems and Sensory Issues
Social behavior and sensitivities closely align with what is seen in autism spectrum disorders. The child has no interest in, nor can he easily maintain relationships. Deficits in social function lean towards extreme impairment in the capacity to interact successfully with others. Disinterested and detached from everything going on around him, the lack of empathy and possible senses overload drives him to avoid contact with others whenever possible. He has trouble reading the emotions of others, as well as interpreting them, and does not know how to react.
Inability to Regulate Feelings
Autistic children with this subtype have problems with affection and emotions, as well as relating to others. Chronic anxiety and panic attacks, irritability, and especially emotional instability drive a child affected by multiple-complex developmental disorder. With assorted phobias, fears, and episodes of uncontrollable anger, he often overreacts; sometimes to the point of self harm. At times, he will display inappropriate emotions and immature behavior which can also make him clingy.
Irrational Thoughts
With this subtype, an autistic child does not have normal thought processes. He dreams up illogical or bizarre ideas and come to outrageous conclusions. Delusions and paranoia are common. He does not handle stress very well. Any form of distress, initiates episodes of disorganized, irrational thinking or distorted perceptions characteristic of his nature. He may even think he has special powers. Magical thinking is common as he gets reality and fantasy mixed up.
No Autism Interventions for Multiplex Developmental Disorder
While each category must be present to make a diagnosis, the areas can certainly overlap. An inability to tolerate the frustrations and anxiety that tag along with social interaction, for example, can create an environment ripe for highly disorganized behavior and/or paranoia. However, behavior and thought problems do not reach the level of psychosis seen in schizophrenia. While changes in routine or anything perceived as stress causes many autistic children to stim, for the MCDD child, stress generally ushers in disorganized thought.
Since this is a new category, there are no special autism interventions yet. Children diagnosed with the disorder are currently classified as pervasive developmental disorder, not otherwise specified (PDD-NOS), and treated under that diagnosis. Look for special education programs that take into account the child’s strengths and talents, and then fine-tunes the program to focus on and address each troubling issue one at a time.
Disclaimer: The information contained in this article is for educational purposes only and should not be used for diagnosis or to guide treatment without the opinion of a health professional. Any reader who is concerned about his or her child's health should contact a doctor for advice.
Sources:
- Growing Together Therapeutic Center, “Multiplex Developmental Disorder (MCDD)” (accessed December 19, 2010)
- McDD – Portal, “Information – DSM-IV-TR & ICD-10” and “PDD-NOS and MCDD in the DSM” (both accessed December 19, 2010)
- Volkmar, Fred R., Paul, Rhea, Klin, Ami and Cohen, Donald J., Handbook of Autism and Pervasive Developmental Disorders: Assessment, Interventions, and Policy (Volume 2), Wiley (third edition), April 2005
- Yale School of Medicine, Child Study Center, “Multiplex Developmental Disorder” (accessed December 19, 2010)
Vickie Ewell - Vickie has worked with autistic individuals for 9 years. She has celiac disease and specializes in gfcf living.
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