It's wise to keep in mind other conditions that may mimic the symptoms of autism. Developmental milestones may be missed for reasons that are not related to ASD.
Sometimes we look to label a child with autism, so that access to support is more readily available. It is important, however, to focus on making a diagnosis that is the most accurate, so that the treatments are chosen that address the needs of the child. As a parent, being armed with knowledge and asking questions will help the professionals make a diagnosis that results in the best care for your child.
Sensory issues are often misdiagnosed as autism because of some similarity in behaviours. Many kids with sensory issues will experience some of the same behaviours as those with autism. People with Autism may have sensory issues. However, I don't think that sensory issues should always be considered a form of autism. Some kids with sensory issues may have difficulty processing information or understanding social cues. Other kids with sensory issues will have difficulties with language or motor skills.
One reason that it's important to explore treatments for sensory issues prior to an autism diagnosis, is that a child may overcome many difficulties once the sensory issues are addressed.
Anxiety is another condition that can look similar to autism. Anxiety is characterised by extreme fearfulness and avoidance behaviour. Kids with anxiety often avoid situations that make them feel anxious. Your child may also be very sensitive to noise, lights, smells and textures. Anxious kids may also have trouble sleeping or eating.
Selective mutism may also be associated with heightened anxiety, which may mimic some of the communication difficulties that can be a sign of autism.
Kids with anxiety may also exhibit repetitive behaviours such as rocking back and forth, hand flapping or spinning. Some kids with anxiety may also have sensory issues.
The most obvious difference between autism and anxiety is that kids with anxiety usually understand what others mean when they talk to them. Kids with anxiety do not have problems communicating their thoughts and feelings.If your child has signs of anxiety, it would be wise to seek the help of a psychologist that specialises in children's anxiety.