Health Library

Symptoms may include:

• Avoiding eye contact
• Avoiding social contact and preferring to be alone
• Not imitating others
• Not understanding other people's feelings and needs
• Failing to seek and even avoid personal attention
• Being physically aggressive
• Being self-destructive
• Often having tantrums, even with very little to provoke them

Symptoms may include:

• Never speaking—Some children with autism may not be able to learn how to speak. Or, they may only speak a few words.
• Using language in unusual ways. Some children use incorrect words and change the meaning of common words.
• Only echoing what they have heard, and speaking on their own.
• Trouble with nonverbal communication—Body language is used and interpreted wrongly. For example, a hug may be considered an assault.
• Not reacting to smiles the way a normal child would.

Autistic children usually:

• Do not play imaginatively
• Lack interest in normal activities for their age
• May spend hours doing a single activity over and over again. For example, rocking or flapping a hand
• May gesture frequently, or stare at specific objects
• Demand consistency and predictability in their surroundings—Tiny changes may cause angry reactions
• May be hyperactive, passive, and single-minded
• Resist change

Signs may include:

• An unusual sensitivity to sound, smell, taste, sights, and touch
• Responding to stimulation in unusual ways
• Sniffing or licking toys
• Feeling pain from a light touch, but ignoring more severe pain
• Experiencing sounds as colors, and touches as sounds

Some people with autism have other disorders as well. These may include:

• Seizures—These occur when communication between nerve cells in the brain is disturbed. This can cause strange sensations, emotions, and behavior. Also common are convulsions, muscle spasms, and loss of consciousness.
• Intellectual disability—A condition that includes limitations in both intelligence and adaptive skills.
• Conditions affecting digestion, such as:
  • Gastroesophageal reflux disease
  • Malabsorption
  • Diarrhea
  • Not having a lot of food interests
• Failure-to-thrive
• Genetic disorders—Examples include:
  • Tourette syndrome—This is a neurological disorder. The symptoms are tics, rapid, involuntary movements, or sounds that occur repeatedly.
  • Fragile X syndrome—This is an inherited disorder of the X chromosome. It is the most common cause of inherited intellectual disability.
  • Phenylketonuria (PKU)—PKU is a genetic disorder of the enzyme that breaks down phenylalanine. Phenylalanine is an amino acid found in certain foods. Without a proper diet, PKU can lead to intellectual disability.
  • Tuberous sclerosis—This is a genetic disorder of the nervous system. It causes tumors to grow on the nerves in any part of the body. Neurofibromatosis can also produce other abnormalities. For example, changes in the skin or deformed bones.