Autism FAQ - Similar Conditions

There are a number of diseases which cause children to display some of the symptoms of autism. Also, on occasion, brain injury has caused people to display some of the symptoms of autism. Some diseases:

Some children who exhibit symptoms similar to autism have been discovered to be deaf. A child should always have his hearing checked before being identified as autistic.
Inborn error in carbohydrate metabolism. [Inability to metabolize galactose?]
Heller's Disease
Normal development to age 3 or 4, then abrupt onset of fretfulness, negativism and anxiety. Regression of mental development and gradual loss of speech.
LKS "Landau-Kleffner Syndrome"
Also Acquired Childhood Epileptic Aphasia. Very rare disorder. Typical profile: normal development and age appropriate language first 3-7 years; Loss of receptive language while retaining some expressive language; "Telegraphic" speech--few verbs; Suspicion of deafness; Child frustrated, puzzled by change in himself; Autistic-like behaviors; normal or above normal non-verbal IQ score; abnormal EEG, with or without seizures. Some practitioners suspect that some cases of Childhood Disintegrative Disorder or "late outset" autism may be Landau-Kleffner Syndrome.
PKU "Phenylketonuria"
A genetic disorder of the metabolism which will result in brain-damage during the first years of life unless special dietary measures are taken. Inadequate production of the enzyme which converts the amino acid phenylalanine into another amino acid, tyrosine. The extra phenylalanine accumulates in body fluids and converts to several chemicals that damage the brain. Symptoms include mental retardation as well as some of the symptoms of autism. PKU has been eliminated by screening all children immediately after birth so proper dietary measures can be taken.
Rett's Syndrome
a neurological disorder that occurs only in girls. Unlike autism, girls initially show normal development, then revert. The initial symptoms include some that are associated with autism. From DSM IV:


    A. All of the following:

    (1) apparently normal prenatal and postnatal development (2)
    apparently normal psychomotor develop (3) normal head circumference
    at birth

    B. Onset of all of the following after a period of normal

    (1) deceleration of head growth between ages 5 and 48 months (2)
    loss of previously acquired purposeful hand skills between ages 5
    and 30 months with subsequent development of stereotyped hand
    movements (e.g.  hand wringing or hand washing) (3) loss of social
    engagment early in the course (although social interaction often
    develops later) (4) appearance of poorly coordinated gait or trunk
    movements (5) severely impaired expressive and receptive language
    development with severe pyschomotor retardation.

Childhood Disintegrative Disorder
Much rarer than autism. I've seen references which treat this as a synonym for Heller's Disease (see above). From DSM IV:


    A. Apparently normal development for at least the first 2 years
    after birth as manifested by the presence of age appropriate verbal
    and nonverbal communication, social relationships, play and adaptive

    B. Clinically significant loss of previously acquired skills
    (before age 10 years in at least two of the following areas:

    (1) expressive or receptive language (2) social skills or adaptive
    behavior (3) bowel or bladder control (4) play (5) motor skills

    C. Abnormalities of functioning in at least two of the following

    (1) qualitative impairment in social interaction (e.g., impairment
    in nonverbal behaviors, failure to develop peer relationships, lack
    of social or emotional reciprocity)

    2) qualitative impairments in communication (e.g., delay or lack of
    the development of spoken language, inability to initiate or sustain
    a conversation, stereotyped and repetitive use of language, lack of
    verbal make-believe play)

    (3) Restricted repetitive & stereotyped patterns of behavior,
    interests and activities, including motor stereotypes and

    D. The disturbance is not better accounted for by another specific
    Pervasive Developmental Disorder or by Schizophrenia.

Tourette's Syndrome
a condition thought to be genetic that causes uncontrollable motor and/or vocal tics. A major longterm study is being conducted by David Cummings, who published a thick book on the genetic links between various neurological disorders. (Not easy reading.)
Obsessive-compulsive disorder
Obsessions are thoughts or images that are involuntary, intrusive, and anxiety-provoking. Compulsions are impulses to perform a variety of stereotyped behaviors or rituals. OCD is a neurological disorder, cause uncertain. However, it is often confused with obsessions and compulsions caused by mental illness or simple neurosis, in much the way that the term "Autism" has been used to refer to any person who is severely withdrawn. For a clearer picture of OCD, read The Boy Who Wouldn't Stop Washing (Judith Rapaport). Clinical OCD has easily categorized symptomology that tend to occur at certain stages of life; counting and sorting and "evening out" usually start during childhood, "grooming" compulsions usually start at puberty, and "ruminating" (obsessions) usually begin during adulthood.
Cocktail party speech syndrome
a syndrome comprising the following characteristics: (1) A perseveration of response, either echoing the examiner, or repetition of an earlier statement made by the child. (2) An excessive use of social phrases in conversation. (3) An over-familiarity in manner, unusual for one's age. (4) A habit of introducing personal experience into the conversation in irrelevant and inappropriate contexts. (5) Fluent and normally well articulated speech.
Asperger's Syndrome
Similar to Autism except that language development is normal. In some people's minds, the same thing as high-functioning Autism. From DSM IV (p77):


    A. Qualitative impairment in social interaction, as manifested by
    at least two of the following:

    (1) marked impairments in the use of multiple nonverbal behaviors
    such as eye-to-eye gaze, facial expression, body postures, and
    gestures to regulate social interaction

    (2) failure to develop peer relationships appropriate to
    developmental level

    (3) a lack of spontaneous seeking to share enjoyment, interests, or
    achievements with other people (e.g. by a lack of showing,
    bringing, or pointing out objects of interest to other people)

    (4) lack of social or emotional reciprocity

    B. Restricted repetitive and stereotyped patterns of behavior,
    interests, and activities, as manifested by at least one of the

    (1) encompassing preoccupation with one or more stereotyped and
    restricted patterns of interest that is abnormal either in
    intensity or focus

    (2) apparently inflexible adherence to specific, nonfunctional
    routines or rituals

    (3) stereotyped and repetitive motor mannerisms (e.g., hand or
    finger flapping or twisting, or complex whole-body movements)

    (4) persistent preoccupation with parts of objects

    C. The disturbance causes clinically significant impairments in
    social, occupational, or other important areas of functioning

    D. There is no clinically significant general delay in language
    (e.g., single words used by age 2 years, communicative phrases used
    by age 3 years)

    E. There is no clinically significant delay in cognitive
    development or in the development of age-appropriate self-help
    skills, adaptive behavior (other than social interaction), and
    curiosity about the environment in childhood

    F. Criteria are not met for another specific Pervasive
    Developmental Disorder of Schizophrenia

Nonverbal learning disabilities
Semantic-pragmatic speech disorder (Semantic Pragmatic Disorder or SPD)
A communication problem with mild autistic symptoms and problems generalizing.
a mental illness which can result in behavior similar to autism. Unlike autism, schizophrenia usually starts in adolescence or early adulthood, and involves delusions or hallucinations. Note that "Childhood Schizophrenia" used to refer to what we now label "Autism" and that the former term is still used in some circles.
PDD or PDD/NOS or PDD-NOS "Pervasive Development Disorder/Not Otherwise Specified"
PDD therefore becomes a term for individuals who do not fully meet the medical criteria for autism, but it is a very loose term. From DSM IV:

    NOT OTHER SPECIFIED (including Atypical Autism)

    This category should be used when there is a severe and pervasive
    impairment the development of reciprocal social interaction,
    verbal and nonverbal communication skills, or when the stereotyped
    behavior, interest and activities are present, but the criteria are
    not met by a specific Pervasive Developmental Disorder,
    Schizophrenia, Schizotypal Personality Disorder or Avoidant
    Personality Disorder. For example, this category includes "atypical
    autism" - presentations that do not meet the criteria for Autistic
    Disorder because of late age at onset, atypical symptomatology, or
    subthreshold symptomology (note; fewer than 6 items), or all

mucopolysaccharoidoises (Type I)
Has coincided with autism.
adenylosuccinate lyase deficiency
a disorder of nucleic acid metabolism. Has coincided with autism.
Childhood aphasia
Receptive Developmental Dysphasia
Celiac's disease
Gluten intolerance (?)
Fragile-X Syndrome
The most common cause of inherited mental retardation, with an incidence of about 1/1500 in males and 1/2500 in females. The inheritance pattern of the disease is unlike other X-linked disorders, because it shows significant numbers of apparently unaffected male carriers and some clinically affected females. The disease derives its name from the presence of a fragile site on the X chromosome of affected individuals.
ADD "Attention Deficit Disorder"
A disorder consisting of having a short attention span. Dr. C. Gillberg from Sweden has proposed (in addition to others) that there may be a continuum from ADD to autism. He proposes that some kids are in the middle of the continuum, with a combination of ADD and autistic features. These kids often have "soft" neurologic signs (incl. fine and/or gross motor coordination problems) in addition to their ADD, and are socially awkward.
ADHD "Attention Deficit Hyperactivity Disorder"
Another term for ADD when the person is also hyperactive. Thought to be caused by a chemical imbalance in the brain, which results in a biological deficiency in a childs ability to concentrate. Diagnosis of ADHD is a grey area: there are 18 criteria involved in identifying ADHD including such traits as inability to concentrate and aggressiveness. The question of how many criteria a child must have before pharmaceutical treatment is however still debated. A daily dose of a controversial prescription drug called RITALIN, has been reported to cause marked improvement in childrens behaviour.
Tuberous Sclerosis
a disorder consisting of precocious reading development, disordered language acquisition and social and behavioral deficits. It is a matter of discussion whether to consider it a type of autism or asperger's syndrome.
Manic Depression
Autistic Children who have no apparent neurological basis for their disorders may actually be suffering from an inherited, early-onset form of manic-depression, according to results of two studies conducted at Duke University Medical Center, Durham, NC. The findings were reported in the May and August 1994 issues of "Developmental Medicine and Child Neurology."
Angelman Syndrome
resembles autism only superficially since Angelman kids are profoundly retarded and (somtimes?) don't exhibit the lack of empathy, eye contact, etc. typical of autism. It is caused by a particular defect in chromosome 15 which can be diagnosed accurately by chromosome testing. The other name for it is the Happy Puppet because the children's limbs are usually held out from the body stiffly and the children always have a smiling countenance. Besides extreme retardation, other symptoms include low muscle tone, recurring seizures, sleep disorders, gastrointetinal problems, and slow development. Another syndrome caused by a defect in chromosome 15 is Prader-Willi.
Smith-Magenis Syndrome
has a lot of autistic characiteristics. Caused by a particular defect in the 17th chromosome.
Klinefelter Syndromes
Having an XXY chromosome. It is easily testable through genetic testing and occurs in about 1 in 1000 births. Often includes developmental and language impairment, and has been correlated with some kinds of withdrawn behavior.
DAS "Developmental Apraxia of Speech"
Also known as "Developmental Verbal Dyspraxia". A neurologically-based speech disorder observed in children learning to speak. It affects the rate of speech development, the number of sounds in a child's repertoire, and the child's ability to combine sounds during the production of words.
Lactic Acidosis
tendency to accumulate of lacitic acid in the blood. It's connection with autism is that it has been found to coincide with autism more than chance would dictate.
The inability to recognize faces, also known as face blindness.
Irlen Syndrome/Scotopic Sensitivity Syndrome (SSS)
Visual perceptual problem identified by Helen Irlen which causes (among other things) black-on-white print to be difficult to read, and which can be alleviated by filtering out portions of the light spectrum with colored glasses. See Irlen Lenses under treatment.
Turner's syndrome
A syndrome in females where they are missing one of their two X chromosomes.
Carnitine Deficiency
A condition which can have symptoms similar to Reye's Syndrome. It can be caused by genetic factors.

Others I've heard mentioned: Congenital Rubella Syndrome, Hypomelanosis of Ito, mucopolysacchrides, fetal alcohol effect, cocaine use during pregnancy, Anxiety disorders, Mucopolysaccharidoses (MPS), Lesch-Nyhan Syndrome, Intermittent Explosive Disorder, static encephalopathy, sleep disorder, abnormal fear structure, Cornelia de Lange Syndrome, Wilsons Disease, Aphasia, Schizoid Personality Disorder, Porphyria (?), Bi-Polar Affective Disorder, Defiant Disorder, Spacial Planning Disorder, Neurofibromatosis, Candida Albicans.