What causes autism?

Since autism was first added to the psychiatric literature fifty years ago, there have been numerous studies and theories about its cause. Researchers still have not reached agreement regarding its specific causes. First, it must be recognized that autism is a set of a wide variety of symptoms and may have many causes. This concept is not unusual in medicine. For instance, the set of symptoms that we perceive of as a “cold” can be caused by literally hundreds of different viruses, bacteria, and even our own immune system. Autism is, undoubtedly, a biologically-based disorder. In the past, some researchers had suggested that autism was the result of poor attachment skills on the part of the mother. This belief has caused a great deal of unnecessary pain and guilt on the part of the parents of autistic children, when in fact, the inability of the individual with autism to interact appropriately is one of the key symptoms of this developmental disorder.

In support of a biological theory of autism, several known neurological disorders are associated with autistic features. Autism is one of the symptoms of these disorders. These conditions include tuberous sclerosis (an inherited disorder), the fragile X syndrome, cerebral dysgenesis (abnormal development of the brain), Rett syndrome, and some of the inborn errors of metabolism (biochemical defects). Autism, in short, seems to be the end result or “final common pathway” of numerous disorders that affect brain development. In general, however, when clinicians make the diagnosis of autism, they are excluding the known causes of autistic behaviors. However, as the knowledge of conditions that cause autism advances, fewer and fewer cases will be thought of as being “pure” autism and more individuals will be identified as having autism due to specific causes.

There is a strong association between autism and seizures. This association works in two ways: First, many patients (20% to 30%) with autism develop seizures. Second, patients with seizures, which are probably due to other causes, may develop autistic-like behaviors. One special and often misunderstood association between autism and seizures is the Landau-Kleffner Syndrome. This syndrome is also known as acquired epileptic aphasia. Some children with epilepsy develop a sudden loss of language skills–especially receptive language (the ability to understand). Many often also develop the symptoms of autism.

These children often, but not always, have a characteristic pattern of electrical brain activity seen on EEG (electroencephalogram) during deep sleep called electrographic status epilepticus during sleep (ESES). The usual age of onset of language loss or regression is around four years of age, which makes the Landau-Kleffner syndrome distinguishable from autism on these grounds, in that autism usually is first exhibited in younger children. However, in recent years, some children (very, very few) who did not exhibit overt (observable) seizures were found to have Landau-Kleffner syndrome.

The importance of these findings is that, although rare, the Landau-Kleffner syndrome can resolve spontaneously and in some cases can be treatable with prednisone, a steroid medication related to cortisone. This association between the Landau-Kleffner syndrome and autism has led many clinicians and families to search for the typical EEG pattern (ESES) in autistic individuals. This unusual EEG pattern is seen only in deep sleep, which usually requires prolonged recordings of up to 12 hours. Many, many autistic children and adults will display some abnormalities on their sleep EEG, but probably very few have true Landau-Kleffner syndrome that will respond to treatment.

It must also be noted that prednisone, in the very high doses used to treat Landau-Kleffner syndrome, almost invariably produces side effects, which may include weight gain, high blood pressure, diabetes, growth failure, stomach ulcers, irritability, destruction of the hip joint, and susceptibility to infectious disease (suppressed immune system). While most of these side effects are reversible, some of the complications of high dose prednisone therapy can be irreversible and even fatal.

Other treatments ranging from common anticonvulsant therapy to surgery have been proposed and are being tried for Landau-Kleffner syndrome. It is difficult to evaluate the true effects of any treatment for Landau-Kleffner syndrome due to the high rate of spontaneous resolution of symptoms (remission).

6 Top Vaccine Myths

Hours after a baby is born, her parents are told it’s best that she receive her first shot before she leaves the hospital. And that’s just the beginning. By the child’s sixth birthday, she’ll have had at least 35 vaccinations—if she goes by government recommendations. Meanwhile, during those six years, her parents are likely to see hundreds of media reports and online message-board debates about which vaccines are necessary or even safe. It’s confusing, to say the least.

To sort through the onslaught of information and misinformation about childhood immunizations, we asked Austin, Texas-based pediatrician Ari Brown, coauthor of “Baby 411: Clear Answers and Smart Advice for your Baby’s First Year,” to debunk some of the most common vaccination myths.

Myth 1: It’s not necessary to vaccinate kids against diseases that have been largely eradicated in the United States.
Reality: Although some diseases like polio and diphtheria aren’t often seen in America (in large part because of the success of the vaccination efforts), they can be quite common in other parts of the world. The Centers for Disease Control and Prevention warns that travelers can unknowingly bring these diseases into the United States, and if we were not protected by vaccinations, these diseases could quickly spread throughout the population. At the same time, the relatively few cases currently in the U.S. could very quickly become tens or hundreds of thousands of cases without the protection we get from vaccines. Brown warns that these diseases haven’t disappeared, “they are merely smoldering under the surface.”

Most parents do follow government recommendations: U.S. national immunization rates are high, ranging from 85 percent to 93 percent, depending on the vaccine, according to the CDC. But according to a 2006 study in the Journal of the American Medical Association, the 20 states that allow personal-belief opt outs in addition to religious exemptions saw exemptions grow by 61 percent, to 2.54 percent between 1991 and 2004.

Brown is concerned that parents who opt out or stagger the vaccine schedule can end up having to deal with confusing follow-up care, which could produce an increase in disease outbreaks like last summer’s measles epidemic. A 2008 study in the American Journal of Epidemiology reported that when there are more exemptions, children are at an increased risk of contracting and transmitting vaccine-preventable diseases.

Myth 2: Mercury is still in kids’ vaccines.
Reality:
At the center of this issue is a preservative called thimerosal compound containing mercury) that once was a common component in many vaccines because it allowed manufacturers to make drugs more cheaply and in multidose formulations. But public concern, new innovations and FDA recommendations led to its removal from almost all children’s vaccines manufactured after 2001. Since flu vaccines are not just for children, manufacturers still put thimerosal in some flu-shot formulations. You can ask your pediatrician for the thimerosal-free version, says Brown.

If your child does not have asthma and is at least 2 years old, Brown recommends the FluMist nasal-spray vaccination over the flu shot. “It seems to have better immune protection and it could help your child avoid another shot,” she says. (Caveat: the spray does contain a live version of the virus, which can result in a slight increase in flulike symptoms).

Myth 3: Childhood vaccines cause autism.
Reality:
There is no scientific evidence that this link exists. Groups of experts, including the American Academy of Pediatrics and the Institute of Medicine (IOM), agree that vaccines are not responsible for the growing number of children now recognized to have autism.

Earlier this month, the law supported scientists’ conclusions in this arena with three rulings from a section of the U.S. Court of Federal Claims, which stated that vaccines were not the likely cause of autism in three unrelated children. The U.S. Department of Health and Human Services said in an online statement following the ruling, “The medical and scientific communities have carefully and thoroughly reviewed the evidence concerning the vaccine-autism theory and have found no association between vaccines and autism.” Noting the volume of scientific evidence disproving this link, an executive member of one of the nation’s foremost autism advocacy groups, Autism Speaks, recently stepped down from her position because she disagrees with the group’s continued position that there is a connection between the vaccines and autism.

Myth 4: Getting too many vaccines can overwhelm the immune system and cause adverse reactions or even serious illness.
Reality:
Children’s immune systems are capable of combating far more antigens (weak or killed viruses) than they encounter via immunizations. In fact, the jury is still out on if there’s an actual limit on how many the body can handle—though one study puts the number around a theoretical 10,000 vaccines in one day.(Visit the American Academy of Pediatrics’ site or the Network for Immunization Information for more information)

Currently, “There is even less of a burden on the immune system [via vaccines] today than 40 years ago,” says Edgar Marcuse, a professor of pediatrics at the University of Washington who works on immunization policy and vaccines. He points to the whooping-cough vaccine as an example where there are far fewer antigens in the shot than the earlier version administered decades ago. Brown says she supports following the recommended schedule for vaccinations, which outlines getting as many as five shots in one day at a couple check-ups.

The CDC reports that most vaccine adverse events are minor and temporary, such as a sore arm or mild fever and “so few deaths can plausibly be attributed to vaccines that it is hard to assess the risk statistically.” Of all deaths reported to the Health and Human Services’ Vaccine Adverse Events Reporting site between 1990 and 1992, only one is believed to be even possibly associated with a vaccine. The Vaccine Safety Datalink Project, an initiative of the CDC and eight health-care organizations, looks for patterns in these reports and determines if a vaccine is causing a side effect or if symptoms are largely coincidental.

If you have concerns about following the recommended vaccination, schedules don’t wait until a check-up. Set up a consultation appointment with your pediatrician, or even outline a strategy for care with your doctor during your pregnancy.

Myth 5: It’s better to let my kid get chickenpox “naturally.”
Reality:
Before the chickenpox vaccine was licensed in 1995, parents sometimes brought their child to a party or playground hoping that their child might brush up against a pox-laden kid to get their dose of chickenpox over since cases were usually less severe for children than adults. But pediatricians say severe complications are possible with chickenpox—including bacterial infections that could result in a child’s hospitalization or death.

Now that there’s a vaccine for chickenpox, more than 45 states require the shots (unless your child already had the chicken pox or can prove natural immunity). Two shots usually guarantees your child a way out of being bedecked in calamine lotion for two feverish weeks, but some individuals do still come down with a milder form of the pox. Most pediatricians recommend getting the shot.

Myth 6: The flu shot causes the flu.
Reality:
The flu shot does not contain a live virus, so your child can’t get the flu from this shot. But, after the shot, it’s not uncommon to feel a bit achy while the immune system mounts its response. Remember that for two weeks following the shot, your child can still get the flu, so be sure to help your child avoid that feverish kid next door.

Autism: Kids Put At Risk

James Coman’s son has an unusual skill. The 7-year-old, his father says, can swallow six pills at once.

Diagnosed with autism as a toddler, he had been placed on an intense regimen of supplements and medications aimed at treating the disorder. He was injected with vitamin B12 and received intravenous infusions of a drug used to leach mercury and other metals from the body. He took megadoses of vitamin C, a hormone and a drug that suppresses testosterone.

This complex regimen — documented in court records as part of a bitter custody battle over the Chicago boy between Coman, who opposes the therapies, and his wife — may sound unusual, but it isn’t.

Thousands of U.S. children undergo these therapies and more at the urging of physicians who say they can successfully treat, or “recover,” children with autism, a disorder most doctors and scientists say they cannot yet explain or cure.

After reviewing thousands of pages of court documents and scientific studies and interviewing top researchers in the field, an investigation by the Chicago Tribune found that many of these treatments amount to uncontrolled experiments on vulnerable children.

The therapies often go beyond harmless New Age folly, the investigation found. Many are unproven and risky, based on flawed, preliminary or misconstrued scientific research.

Lab tests used to justify therapies are often misleading and misinterpreted. And though some parents fervently believe their children have benefited, the investigation found a trail of disappointing results from the few clinical trials conducted to evaluate the treatments objectively.

Studies show that up to three-quarters of families with children with autism try alternative treatments. Doctors, many linked to the influential group Defeat Autism Now, promote the therapies online, in books and at conferences.

The investigation found children undergoing day-long infusions of a blood product that carries the risk of kidney failure and anaphylactic shock. Researchers in the field emphatically warn that the therapy should not be used to treat autism.

Children are repeatedly encased in pressurized oxygen chambers normally used after scuba diving accidents. This unproven therapy is meant to reduce inflammation that experts say is little understood and may even be beneficial.

Children undergo rounds of chelation therapy to leach heavy metals from the body, though most toxicologists say the test commonly used to measure the metals is meaningless and the treatment potentially harmful.

Last year, the National Institutes of Health halted a controversial government-funded study of chelation before a single child with autism was treated. Researchers at Cornell University and UC Santa Cruz had found that rats without lead poisoning showed signs of cognitive damage after being treated with a chelator.

Doctors associated with the autism recovery movement often say they know that more research is needed but that children need help now.

“We can’t wait for 10 or 20 years,” pediatrician Dr. Elizabeth Mumper, medical coordinator for the Autism Research Institute (the nonprofit parent organization of Defeat Autism Now), testified in a special federal court.

Many parents who try alternative therapies cite an analogy popularized by a luminary of the movement: It’s as if their child has jumped off a pier. Science hasn’t proved that throwing a life preserver will save the child, but they have a duty to try, right?

Critics say that’s the wrong way to think about it.

“How do they know the life preserver is made of cork and not lead?” said Richard Mailman, a neuropharmacologist at Penn State University. “However desperate you are, you don’t want to throw your child a lead life preserver.”

“Dangerous experimentation” is how pediatrician Dr. Steven Goodman, a clinical trial expert at the Johns Hopkins Berman Institute of Bioethics, describes use of these unproven therapies.

One in 100 U.S. children is diagnosed with autism spectrum disorder by age 8, according to the U.S. Centers for Disease Control and Prevention. Though behavioral therapies can help, there are no cures for the disorder, which is characterized by communication problems, difficulties interacting socially and rigid, repetitive behavior.

But clinicians and others in the recovery movement readily offer treatments and hope.

The Symptoms of Autism

The current Diagnosis and Statistical Manual of Mental Disorders-Fourth Edition, Treatment Revision (DSM-IV-TR) identifies three features that are associated with autism:

  • impairment in social interaction,
  • communication, and
  • Behavior.

Impairment in social interaction

First, patients with autism fail to develop normal personal interactions in virtually every setting. This means that affected persons fail to form the normal social contacts that are such an important part of human development. This impairment may be so severe that it even affects the bonding between a mother and an infant. It is important to note that, contrary to popular belief, many, if not most, autistic persons are capable of showing affection and do demonstrate affection and do bond with their mothers or other caregivers. However, the ways in which autistic individuals demonstrate affection and bonding may differ greatly from the ways in which others do so. Their limited socialization may erroneously lead parents and pediatricians away from considering the diagnosis of autism. As the child develops, interaction with others continues to be abnormal. Affected behaviors can include eye contact, facial expressions, and body postures. There is usually an inability to develop normal peer and sibling relationships and the child often seems isolated. There may be little or no joy or interest in normal age-appropriate activities. Affected children or adults do not seek out peers for play or other social interactions. In severe cases, they may not even be aware of the presence of other individuals.

Communication

Communication is usually severely impaired in autistic persons. What the individual understands (receptive language) as well as what is actually spoken by the individual (expressive language) is significantly delayed or nonexistent. Deficits in language comprehension include the inability to understand simple directions, questions, or commands. There may be an absence of dramatic or pretend play and these children may not be able to engage in simple age-appropriate childhood games such as Simon Says or Hide-and-Go-Seek. Adults may continue to engage in playing with games that are for young children.

Autistic individuals who do speak may be unable to initiate or participate in a two-way conversation (reciprocal). Frequently the way in which an autistic person speaks is perceived as unusual. Their speech may seem to lack the normal emotion and sound flat or monotonous. The sentences are often very immature: “want water” instead of “I want some water please.” Those with autism often repeat words or phrases that are spoken to them. For example, you might say “look at the airplane!” and the child or adult may respond “at airplane,” without any knowledge of what was said. This repetition is known as echolalia. Memorization and recitation of songs, stories, commercials, or even entire scripts is not uncommon. While many feel this is a sign of intelligence, the autistic person usually does not appear to understand any of the content in his or her speech.

Autistic persons often exhibit a variety of repetitive, abnormal behaviors. There may also be a hypersensitivity to sensory input through vision, hearing, or touch (tactile). As a result, there may be an extreme intolerance to loud noises or crowds, visual stimulation, or things that are felt. Birthday parties and other celebrations can be disastrous for some of these individuals. Tags on clothing may be perceived as painful. Sticky fingers, playing with modeling clay, eating birthday cake or other foods, or walking barefoot across the grass can be unbearable. On the other hand, there may be an underdeveloped (hyposensitivity) response to the same type of stimulation. This individual may use abnormal means to experience visual, auditory, or tactile (touch) input. This person may head bang, scratch until blood is drawn, scream instead of speaking in a normal tone, or bring everything into close visual range. He or she might also touch an object, image or other people thoroughly just to experience the sensory input.

Autistic children and adults are often tied to routine and many everyday tasks may be ritualistic. Something as simple as a bath may only be accomplished after the precise amount of water is in the tub, the temperature is exact, the same soap is in its assigned spot and even the same towel is in the same place. Any break in the routine can provoke a severe reaction in the individual and place a tremendous strain on the adult trying to work with them.

There may also be non-purposeful repetition of actions or behaviors. Persistent rocking, teeth grinding, hair or finger twirling, hand flapping and walking on tiptoe are not uncommon. Frequently, there is a preoccupation with a very limited interest or a specific plaything. A child or adult may continually play with only one type of toy. The child may line up all the dolls or cars and the adult line up their clothes or toiletries, for example, and repeatedly and systematically perform the same action on each one. Any attempt to disrupt the person may result in extreme reactions on the part of the autistic individual, including tantrums or direct physical attack. Objects that spin, open and close, or perform some other action can hold an extreme fascination. If left alone, an autistic person may sit for hours turning off and on a light switch, twirling a spinning toy, or stacking nesting objects. Some individuals can also have an inappropriate bonding to specific objects and become hysterical without that piece of string, paper clip, or wad of paper.