Continuing progress in the diagnosis of autism. (EP On Autism).

This month's Autism Spotlight centers on the diagnosis of autism. This first article explores the overall landscape in diagnosis, principally as it involves patients at the far ends of the spectrum, i.e. acute or very mild. The following article examines the great strides made in the diagnosis of autism in the very young. In coming months, this 14-part series will attempt to explore all areas of autism including alternative approaches. Reader comments and discussion are encouraged at [e-mail].

Parents of children with autism know what autism is. We recognize the signs and symptoms, and most of us can instantly spot another autistic child on the playground or at the supermarket.

But it was not long ago that autism was a difficult and often-missed diagnosis.

Autism is considered a spectrum disorder because symptoms and severity vary from individual to individual. Autism is different in each person with the disorder - no two cases are the same.

It remains a challenging diagnosis at the far ends of the spectrum, when a child is so affected by autism that he or she looks "merely" retarded, or when he or she is so high-functioning that, to many, the child appears "ADD" or "OCD" or "merely" eccentric, not autistic. Today many of these children continue to be misdiagnosed.

But for the wide range of children in the middle of the spectrum, the years of diagnostic research has paid off. The diagnosis of autism has now been standardized, and both the clinical and research criteria are quite reliable. "Reliable," in this sense, means that, using the same criteria, anyone with training will make the same diagnosis for the same child.

Diagnostic consistency is critical because clinicians make autism diagnoses on the basis of symptoms, not causes. There is no blood test or diagnostic scan available for autism; the disorder can only be identified on the basis of observable signs and symptoms.

For autism, as for all of the psychiatric illnesses, these signs and symptoms are listed in a manual called DSM-IV (Diagnostic and Statistical Manual of Mental Disorders IV - see sidebar). If the child has the requisite number of symptoms, the diagnosis of "autism" (pr, alternatively, "pervasive developmental disorder not otherwise specified") can be tirade. This approach is known as a "phenomenological diagnosis" because it is based upon the outward phenomenon that accompany the disorder.

In contrast, many more strictly "medical" diseases can be given an "etiologic diagnosis," meaning that the diagnosis is based on the causes of the illnesses instead of its symptoms.

Take strep throat. The symptoms of strep throat are the patient's report that his throat hurts, and, upon examination, a physician finds inflammation. But a number of different causes can produce an inflamed throat, and the diagnosis of strep is made only when the physician can document that a certain kind of organism-streptococcal baccilli-is present.

Once the bacteria is found, the physician prescribes an antibiotic; if the inflammation is due to a virus, antibiotics will not be effective. Treatment is based on cause, not symptom.

Obviously an etiologic diagnosis is superior to a phenomenologic one. Unfortunately, brain disorders have proved to be so complex that their causes, or etiologies, are still unknown.

So for now we have only a descriptive understanding of what an individual with autism is like: we can "name" the disorder, and describe its symptoms.

The causes of autism remain unknown and them exists no specific medical treatments or cures for autism.

Children with an autism spectrum disorder usually begin to show clear, identifiable symptoms by the age of 18 months. Many parents and experts can usually detect symptoms before this time, however a formal diagnosis is typically made when the child exhibits a noticeable delay in developing language skills - normally between the ages of two and three.

Over the past few years, the National Alliance for Autism Research (NAAR) has made significant investments in a collaborative study designed to identify early signs of autism and whether early intervention can improve the quality of life for children with autism and their families. Researchers involved in the multi-site project, known as the Baby Sibs Study, are examining the infant siblings of children with autism to develop better diagnostic methods and, eventually, more targeted interventions for younger children.

But aside from common signs and symptoms, what do we know about autism in a more profound sense?

* What is the cause or causes of what we now call autism?

* When does it start?

* What has gone wrong or is going wrong presently?

* What parts of the body are affected? How does it progress?

* What will the outcome be?

All of these questions need answers.

There are many areas of research currently underway to tackle these issues-including genetics, brain scanning, biochemistry, etc.-but probably at this point it is fair to say that none of these are more important than the direct evidence obtained from studying the actual brain tissue from affected individuals.

In recognition of this, NAAR, in collaboration with the M.I.N.D. Institute at the University of California at Davis and the Autism Society of America established in 1998 the Autism Tissue Program, which is an ambitious effort to increase the availability of urgently needed brain tissue for autism research. The Autism Tissue Program encourages families nationwide to enroll as organ donors so the brain tissue of individuals with autism and related family members can be used for research. This gift of tissue brings a tremendous acceleration in the progress of autism research.

Also, the ability to study brain tissue is vitally important to the development of effective treatments. Until research determines the "targets" for potential medications (in most cases the target will be a specific receptor on the surface of a brain cell), it will be impossible to undertake "rational drug development" (meaning drug development directed at a specific, known problem in the brain) for the autism spectrum disorders.

For more information on the Autism Tissue Program or how you can help support autism research, please call (888) 777-NAAR or visit www.naar.org

Symptoms

According to the Diagnostic and Statistical Manual (DSM-IV), issued by the American Psychiatric Association, the general symptoms for autistic disorder include:

* A total of six or more impairments in social interaction; communication; and restrictive or repetitive and stereotypical patterns of behavior, interests and activities.

* Delays or abnormal functioning in social interaction; language as a means for communication; or symbolic or imaginative play, with onset before age three.

* Symptoms that cannot be described as Rett Syndrome or Childhood Disintegrative Disorder.

WARNING SIGNS:

Most specialists agree that a child should be evaluated for autism immediately if he or she has:

* Not babbled or cooed by one year

* Not gestured, pointed or waved by one year

* Not spoken a single word by 16 months

* Not spoken a two-word phrase (on his or her own) by two years

* Experiences any loss of any language skills at any age.

OTHER CONCERNS:

Parents should talk to their healthcare provider about an autism evaluation if they notice their child:

* Does not respond to his or her name

* Cannot tell or describe what he or she wants

* Experience any language delays

* Does not follow directions at all

* Appears at times to have a hearing impairment 

* Does not know how to play with toys

* Has poor eye contact

* Appears to be in his or her own world

* Does not smile socially

* Has odd movement patterns

* Has unusual attachment to toys or other objects

* Regularly lines up toys or other items

Eric London, M.D., is co-founder of the National Alliance for Autism Research and the parent of a son with autism.

Established in 1994, the National Alliance for Autism Research (NAAR) is the first private organization in the country dedicated to funding and accelerating biomedical research for autism spectrum disorders. The organization was established by parents of children with autism concerned about the limited amount of funding for autism research. To date, NAAR has committed more than $10 million in grants for biomedical research projects worldwide that seek to find the causes, prevention, effective treatments and, ultimately, cure for autism spectrum disorders. Walk F.A.R. for NAAR is the organization's signature fundraising and autism awareness event, which is held annually in numerous communities across the United States. Additionally, NAAR was instrumental in establishing the Autism Tissue Program, the first parent-led brain tissue donation program dedicated to autism research.