Causes of autism still puzzle experts

Tantri Yuliandini, The Jakarta Post, Jakarta

The scariest thing about autism is the uncertainties over the cause of the disorder. Even after almost 60 years since Dr. Leo Kanner -- a psychiatrist at John Hopkins University -- had defined the word in 1943, doctors and scientists have still failed to pinpoint the cause of autism.

The symptoms of autism itself vary from case to case, of which impairments in social interaction, verbal and non-verbal communication, and imagination, are most prominent.

Although there is no known unique cause of autism, there is growing evidence that autism can be caused by a variety of problems.

According to Stephen M. Edelson of the Center for the Study of Autism in Salem, Oregon, there is some indication of a genetic influence in autism, and that the genetic link to autism may be a weakened or compromised immune system.

Other research showed that depression and or dyslexia were quite common in one or both sides of the family when autism was present, he said in his overview of autism found on the Internet.

Psychologist Adriana S. Ginanjar, however, downplayed genetic factors as the number of people affected by autism was growing each year. In the U.S. it is estimated that there were one in every 200 children with autism, while previously there had been one in every 1000 children.

Autism is three times more likely to affect males than females, Edelson said, however this gender difference was not unique to autism since many developmental disabilities had a greater male to female ratio.

In Indonesia, the number of children affected by Pervasive Development Disorder (PDD), including autism, had also been rising in the last few years by about 10,000 to 12,000 cases annually, accounting for between 0.15 percent to 0.2 percent of the total number of births annually, according to the Ministry of Health.

"Genes do not cause an outbreak, there's been a report from England that autism there is growing fast, and that couldn't be just because of genes," Adriana said in a one-day workshop on increasing communication abilities in autistic children here.

She said that autism was more likely caused by the change in the environment, pollution, wider use of artificial fertilizers, and higher consumption of fast foods.

As an example, Edelson cited the high prevalence of autism in the small town of Leomenster, Massachusetts, where a factory manufacturing sunglasses was once located. Interestingly, the highest proportion of autism cases were found in the homes down- wind from the factory smokestacks.

There was also evidence that a virus can cause autism, and that there was an increased risk in having an autistic child after exposure to rubella during the first trimester of the pregnancy.

Additionally, there were growing concerns that viruses associated with vaccinations, such as the measles component of the MMR (Measles, Mumps, and Rubella) vaccine and the pertussis component of the DTP (Diphtheria, Tetanus, Pertussis) shot, may cause autism.

"This is why many doctors now prefer to delay giving these shots to children under three years old," Adriana said.

Many autistic children also seemed to have an impairment in one or more of their senses, which could involve the auditory, visual, tactile, taste, vestibular, olfactory (smell), and proprioceptive senses.

These senses may be hypersensitive, hyposensitive, or may result in the person experiencing interference, such as a persistent ringing or buzzing sound in the ears. As a result, it may be difficult for them to process incoming sensory information properly.

Edelson said that about 10 percent of autistic individuals had savant skills, or remarkable abilities. These skills were often spatial in nature, such as a special talent in music and art, and mathematical abilities in which some can multiply large numbers in their head within a short period of time. Others could determine the day of the week when given a specific date in history, or memorize a complete airline schedule.

Over the years, families have tried various types of traditional and non-traditional treatments to reduce autistic behaviors and to increase appropriate behaviors.

Food intolerances and food sensitivities were receiving much attention as possible contributors to autistic behaviors, and many families had observed rather dramatic changes after removing certain food items from their children's diet.

Edelson said that researchers had detected the presence of abnormal peptides in the urine of autistic individuals. It is thought that these peptides may be due to the body's inability to breakdown certain proteins into amino acids.

These proteins were gluten such as wheat, barley, and oats; and casein found in human and cow's milk. Many parents had removed these substances from their children's diets and had, in many cases, observed dramatic, positive changes in health and behavior.