Researchers from the United States believe that by using brain scans of infants who have older siblings with autism, it is possible to make a fairly accurate prediction of whether the children studied will also develop autism or not.
The results of a recent study give scientists hope that there is a completely real opportunity Diagnose children with autism spectrum disorder (ASD) before they even show symptoms. Previously, this goal seemed unattainable.
Moreover, the study opens up possibilities and prospects for diagnosing and perhaps even treating autism.
But first, let's figure out why it is so difficult to diagnose autism in children. Typically, a child will begin to show symptoms of autism spectrum disorder (such as difficulty making eye contact) after the age of two. Experts believe that brain changes associated with ASD begin much earlier—perhaps even in the womb.
But various techniques measures of behavior cannot predict who will be diagnosed with autism, says lead study author psychiatrist Joseph Piven of the University of North Carolina at Chapel Hill.
“Children who show signs of autism at age two or three do not appear as if they have autism in their first year of life,” explains Piven.
Many people wonder if there are any genetic “signatures” or biomarkers that could help predict the development of autism. It is noted that there are some rare mutations associated with autism spectrum disorder, but the vast majority of cases cannot be associated with one or even a few genetic risk factors.
Back in the early 1990s, Piven and other researchers noticed that children with autism tend to have slightly larger brains than their peers. This suggested that brain growth may be a biomarker for autism spectrum disorder. But Piven and his colleague Heather Cody Hutzlett, a psychologist at the University of North Carolina at Chapel Hill, note that it's not entirely clear when exactly this overgrowth occurs.
Statistically, autism affects approximately one child in 100 in the general population. But infants who have an older sibling with autism face a greater risk: a 1 in 5 chance of developing ASD.
As part of the Infant Brain Imaging Study program, funded by National institutions US health authorities, Piven and his colleagues scanned the brains of 106 children from the group high risk. The babies were 6, 12 or 24 months old at the time of the study.
Experts used magnetic resonance imaging (MRI) to see if they could “catch” this brain growth in action. In addition, they studied 42 children from the low-risk group.
Fifteen high-risk children were diagnosed with autism at 24 months of age. MRI scans showed that these children's brain volume increased more rapidly between 12 and 24 months compared to children who had not been diagnosed. Researchers say this growth occurred at the same time as behavioral signs autism.
Scientists also found changes in the brain at 6 and 12 months of age, even before ASD symptoms appeared. Cortical surface area, a measure of the size of the folds on the outside of the brain, grew faster in infants who were later diagnosed with autism. Again, in comparison with those children who were not given a similar diagnosis.
It probably arises main question: Is it possible to focus on these brain changes and use them to predict autism in children? Hutzlett and Piven's team then entered the MRI scan data (changes in brain volume, surface area and cortical thickness at 6 and 12 months of age), as well as the children's sex, into a computer program. The goal is to find out which babies are most likely to have autism at 24 months of age.
It turned out that brain changes recorded at 6 and 12 months (among children who had older siblings with autism) successfully identified 80 percent of all babies diagnosed with ASD at 24 months.
In other words, the researchers were able to correctly determine which infants were diagnosed with autism at age two in 80 percent of cases.
The authors clarify that their results still need to be confirmed in subsequent studies. scientific works and with a large number high-risk newborns. In addition, they intend to use other imaging techniques to help detect early brain changes.
Other experts note that even if the results are reliable, clinical application This technique can be quite limited. Specialist Cynthia Schumann from the University of California, Davis, says the findings only apply to infants from high group risk rather than to the general population as a whole. She notes that other studies will be needed to test whether autism can be predicted in non-at-risk children.
It is possible to suspect autism in a child months before the first clinical symptoms appear.
American researchers found quite exact way detect signs of autism in children at high risk - those whose sisters or brothers already suffer from autism spectrum disorder (ASD).
Symptoms of ASD typically appear in a child between 2 and 3 years of age, but researchers believe that the brain changes underlying ASD appear much earlier, perhaps even in utero. Assessment of behavioral disorders does not help with prognosis, nor does genetic research. Although some rare mutations have been linked to autism spectrum disorders, most cases cannot be linked to specific genetic changes.
In the early 1990s, psychiatrist Joseph Piven of the University of North Carolina and other researchers noticed that children with autism tended to have larger brains. However, it was not clear when growth acceleration occurs, so Joseph Piven and his colleague, psychologist Heather Cody Hazlett, used MRI (magnetic resonance imaging) to scan the brains of 106 children at high risk of developing autism, ages 6, 12, and 24 months. Brain scans were also carried out on 42 low-risk children.
Fifteen high-risk children were diagnosed with autism within 24 months. According to MRI data, these children's brain volume increased more rapidly between 12 and 24 months compared to children without a diagnosis of ASD. At the same time, behavioral signs of autism appeared. The researchers also found brain changes between 6 and 12 months, even before ASD symptoms appeared. Moreover, in such children it was observed enhanced growth surface of the cerebral cortex.
The researchers subsequently developed an ASD prediction algorithm based on MRI data that successfully predicted 30 of 37 (81%) autism diagnoses. False positive result was observed in 4 of 142 children who were not subsequently diagnosed with ASD.
“We can now make a fairly accurate prediction, predicting 8 out of 10 cases of autism,” says Dr. Piven. - This has a big impact clinical significance, because behavioral tests in early age give a fifty-fifty chance. Of course, more research is needed, including exploring the ability of other imaging techniques to detect early brain changes.”
“Even if the results are reliable, clinical application may be limited,” said Cynthia Schumann, an expert in medical imaging at the University of California. “For now, we can only talk about the prognosis for children at high risk, and not for the population as a whole.”
Autism affects approximately 1 in 100 children in the general population, but the chance of developing autism in a child whose sibling has ASD is one in five. On this moment There are no known methods to reduce the risk of developing autism, so early diagnosis for now can only serve to inform families.
Autism is characterized by difficulty communicating and speech disorders. Researchers from Columbia University (USA) have proposed a way to diagnose this mental disorder already at an early stage - using MRI analysis of the activity of the speech analyzer in the brain.
Brain tomogram during an audio test; The most active areas are indicated in red, among which the auditory temporal lobes stand out. (Photo by Montreal Neurological Institute.)
According to statistics, autism and related mental disorders at least one child in 110 suffers, but there are still no clear diagnostic criteria that would allow detecting this disease at early stages. Diagnosis is made by external manifestations, of which there are a great many in autism spectrum disorders. Researchers from Columbia University in New York have proposed their own method for unambiguously diagnosing autism, based on the use of functional MRI.
One of characteristic features autistic disorders is a difficulty in communication, which sooner or later manifests itself in the child; Such children speak rarely and poorly and often do not seem to hear what others are telling them. The study involved 15 healthy children and 12 with speech impairments and clear signs autism; On average, all subjects were slightly older than 12 years. During a brain scan using a tomograph, they were given a recording of their parents speaking as if they were talking to them.
In healthy experimental subjects, in response to parental speech, activity of two brain areas- the primary auditory cortex and the superior temporal gyrus, which is responsible for understanding a sentence as an interconnected sequence of words. U autistic children The activity of the primary auditory cortex was the same as in healthy people, but the activity of the superior temporal gyrus was significantly lower. In other words, autistic people with speech impairments literally do not understand what is being said to them; they hear the sentence as a set of unrelated words. Differed in the same way brain activity in healthy and autistic children after taking sedatives: despite the effect of sedatives, the “language understanding” gyrus worked differently in both groups.
An article by researchers with the results of the experiments is being prepared for publication in the journal Radiology.
Autism Spectrum Disorders can be treated, but the key to success here is early detection of the disease. Perhaps the proposed method will significantly facilitate the diagnosis of autism precisely at the key, early stages of its development.
From a medical point of view, autism is complex medical condition With unclear etiology(i.e. reasons for occurrence). In my practice, I try to learn as much as possible about each patient. This requires a thorough examination of the child himself, detailed communication with parents about the medical history, as well as extensive laboratory tests.
Here's where I start my research:
- The actual reception of the patient: the standard ten minutes that the pediatrician graciously grants to the patient is completely insufficient here. Among other things, the conversation should include detailed description medications taken during pregnancy, a description of the food the child took and a story about older relatives: do grandparents and older parents have any quirks?
- Audiology: I had a patient from Canada whose hearing was not tested. The boy was deaf, but not autistic.
- MRI: I'm not a big fan of this procedure. First of all, you need to consider the risks posed by general anesthesia(without it, this study will not be possible, since complete immobility of the child is required). The main practical value of MRI often comes down to the fact that parents are a little encouraged: external signs There's nothing wrong with my brain.
- EEG: often the child does not show any visible seizures of epilepsy (loss of consciousness or muscle tremors). However, prominent doctors involved in the treatment of autism believe that testing brain rhythms (especially if also done during sleep) may have an impact. great value to promptly identify peaks of activity that may harm the brain.
And now the fun begins: You need to somehow convince the child to cooperate with you during the procedure. Then you need to find a good one pediatric neurologist, which will help decipher the received data. Then you need to decide whether to treat areas with increased electrical excitability, since neither anticonvulsant is not completely safe. A very difficult and time-consuming process. - Detailed blood test: very often pediatricians ignore this simple test. If we strive to ensure that the brain is sufficiently saturated with oxygen, we first need to understand whether the child is suffering from anemia.
- Assessing lead and mercury levels in a patient's blood: the theory that heavy metals may somehow be “locked” in the brain is controversial and has generated extensive debate in the medical community. But such a check often helps reassure worried parents. I oppose the introduction of a special provocateur into the body, which will cause the release of heavy metals, without first determining their basic level.
- Other metals: magnesium, calcium and zinc are very important for many substances in the body chemical reactions. Children who are picky eaters often miss out on the most important nutrients. Micronutrient deficiency can lead to skin rashes and digestive problems.
- Performance evaluation thyroid gland: I suggest you logical construction. We have a patient who demonstrates hyperactivity or, on the contrary, lethargy and loss of strength. How can we know that this condition is not related to thyroid health unless we get it checked? Correct answer: no way.
- Chromosomal analysis: Traditional school doctors too often tell parents that autism is genetic disease and treating it with any other means other than classes like ABA is useless. So why not check the chromosomes themselves? If everything is in order with them (at least to the extent that modern genetics can confirm this), then, obviously, biomedical intervention has a significantly higher chance of success than is commonly believed.
- Gastrointestinal health: I prefer to see a detailed coprogram and check the stool for dysbiosis in order to know for sure whether there is a pathological proliferation of pathogenic microorganisms (including yeast) in the intestines, and how the process of digesting proteins, fats and carbohydrates is going. By the way, potty training a child will be much easier when intestinal health is restored.
- Food allergies: when the body reacts to input from external environment agent by releasing immunoglobulins, goes inflammatory process, which undermines the overall energy of the body. Exclusion from food of dishes to which it has been identified increased sensitivity, will help remove the “fog” and establish eye contact and communication.
A gluten- and casein-free diet usually doesn't work in two cases: 1) The patient is not allergic to either gluten or casein; 2) The child continues to receive some third (fourth, fifth...) product to which he has an allergic reaction.
We check children for sensitivity to a very wide range of food products and we advise not some general diet, but a diet specially selected for a particular patient. You should also test your urine for traces of opiate-like substances, which have been linked to poor absorption of gluten and casein in the intestines. - Vitamin levels: It is especially important to know whether the patient is getting enough vitamins A and D from food. This is easy to find out and just as easy to solve with the help of multivitamin supplements.
- Metabolism knowledge: information about how well the patient's kidneys and liver are functioning should be familiar to the attending physician, since this determines the tolerability of many medications.
- Lipid panel: both tall and low level cholesterol can lead to health problems. If cholesterol is very low, this can easily be corrected with medication, often resulting in improvements in eye contact and communication. This information may also influence the composition of the diet used.
