What is Autism Spectrum Disorder?
Autism spectrum disorder (ASD) includes a variety of disabilities related to brain development. People with ASD often have repetitive behaviors or interests, struggle with social interactions, and find changes in their environment distressing due to their limited adaptability. These symptoms emerge early in life and can affect daily activities. ASD often comes with other conditions such as language difficulties, intellectual disabilities, and epilepsy, which are more common in children with ASD than in the general population.
A rare condition called childhood disintegrative disorder (CDD), also known as disintegrative psychosis or Heller syndrome, is grouped under ASD. It’s listed in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as part of the broader category of autism spectrum disorder. What sets CDD apart is its later onset and the fact that children with this condition begin to lose skills they had previously learned, across social, language, and motor domains. The exact cause of CDD is unknown.
Often, children with CDD have achieved what are considered ‘normal’ developmental milestones before this regression begins, which can happen at different ages, but usually after the child turns three. This loss of skills can be so quick and dramatic that the child is aware of it and may even ask what’s happening to them. Some kids might seem to interact with hallucinations, but the standout feature of CDD is the sudden disappearance of previously learned skills. The disorder can become evident when children are already showing delays in development, but these are not always noticeable in their early years. This condition can have a significant negative impact on the child’s life and their family.
What Causes Autism Spectrum Disorder?
The cause of autism is still unknown and its onset can vary greatly. It tends to develop in a sneaky way, without a clear starting point. Kids with an autism spectrum disorder are more likely to also have epilepsy, but we don’t yet know if one causes the other.
Some types of autism, like Childhood disintegrative disorder, are linked to specific diseases, especially when they start later in life:
* Subacute sclerosing panencephalitis: This is a long-lasting brain infection caused by a type of measles virus. It leads to brain inflammation and nerve cells dying.
* Tuberous sclerosis (TSC): This is a genetic disorder causing non-cancerous tumor growth in the brain, but it can also affect other parts of the body like the eyes, kidneys, heart, skin, and lungs.
* Leukodystrophy: In this condition, the protective covering of nerve cells in the brain, the myelin sheath, doesn’t develop normally, leading to brain white matter breaking down.
* Lipid storage diseases: These cause harmful build-ups of fat in the brain and nervous system.
Risk Factors and Frequency for Autism Spectrum Disorder
Some research suggests that Autism Spectrum Disorder (ASD) is becoming more common. We don’t know yet if this is because people are more aware of it, if it is being overdiagnosed, or if the criteria used to diagnose it are too broad. About 1 in 68 people are reported to have ASD. Another condition, called Childhood Disintegrative Disorder, is much rarer. It only occurs in about 1.7 per 100,000 cases, or between 1 to 2 people in 100,000. This makes it approximately 60 times less common than Autism.
Signs and Symptoms of Autism Spectrum Disorder
Autism Spectrum Disorder (ASD) is a condition that typically presents itself with recognizable symptoms by the time a child is two years old. Childhood disintegrative disorder is a type of ASD. Children with this disorder often show the most severe outcomes. They struggle with cognitive and communication abilities. What’s unique about this disorder is that kids typically show a period—called prodrome—in which they frequently get anxious or terrified without clear triggers.
Interestingly, children with childhood disintegrative disorder progress normally at the early stages. They learn verbal and nonverbal communication, social skills, motor skills, and self-care capabilities just like their peers. However, between the ages of 2 and 10, they end up losing almost all of these skills. The losses occur in at least two of the following areas:
- Being able to understand language (receptive language skills)
- Being able to express themselves through speech (expressive language skills)
- Social and self-care skills
- Control over bowel and bladder
- Motor skills
- Play skills
Furthermore, these children experience challenges interacting and communicating socially.
The International Statistical Classification of Diseases (ICD-10) provides criteria to diagnose childhood disintegrative disorder; it includes:
- Normal development until the age of two years. The child needs to display typical milestones for their age in communication, social relationships, play, and adaptive behavior.
- A noticeable loss of skills that had already been acquired when the disorder begins. Certain skills, which are not just neglected but significantly lost in at least two of the following areas, are required for diagnosis:
- Expressing or understanding language
- Play
- Social skills or adaptive behavior
- Controlling bowel or bladder
- Motor skills
- Changes in social functioning, which show up in at least two of the following areas:
- Difficulties in social interactions (similar to those defined for autism)
- Difficulties in communication (as defined for autism)
- Narrow, repetitive, and stereotyped patterns of behavior, interests, and activities
- Loss of interest in objects and the environment
The disorder is not caused by other types of pervasive developmental disorder, acquired aphasia with epilepsy, elective mutism, schizophrenia, or Rett syndrome.
Testing for Autism Spectrum Disorder
If a child is diagnosed with childhood disintegrative disorder, it’s often hard to identify a specific underlying health or brain-related cause. To find out more, doctors perform thorough medical and brain-related checks. These tests are intended to rule out any reversible causes of this condition. Some of the tests they might conduct include:
- Complete blood count to check for general health issues
- Measuring urea, electrolytes, and glucose levels to monitor kidney function and blood sugar levels
- Assessing liver function
- Checking thyroid gland function
- Testing for exposure to hazardous metals
- Screening for HIV
- Testing urine for an excess of particular amino acids
- Using MRI or CT scans to get a detailed view of the brain
- An electroencephalogram (EEG) to measure brain electrical activity
Usually, these tests are conducted during the first assessment once a child has been referred to a specialist. Doctors use EEG and brain imaging studies to rule out other possible diagnoses.
There is also a specific set of criteria, outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM V), that doctors use to confirm the diagnosis. A child must show:
- Poor social interaction and communication skills
- Restricted interests and repetitive behaviors
- These symptoms must interfere with day-to-day life
Treatment Options for Autism Spectrum Disorder
Treatment for a condition called childhood disintegrative disorder is quite similar to how autism is treated. This treatment often prioritizes early and intense educational intervention. The approach is mainly focused on specific behaviors and maintaining a structured environment.
Family counseling is also an essential part of this treatment which can help parents understand how they can support their child’s treatment at home. Depending on the child’s individual needs, they may require treatments to help them with language, social skills, and sensory integration.
Children with this disorder may experience a loss of language, difficulties with social interaction, and self-care. This means they may face ongoing challenges in certain areas, requiring care over the long term. The treatment approach combines behavior therapy, environmental therapy, and medications.
Behavior therapy is applied to train the child to regain mastery of self-care, language, and social skills. The programs are typically set up with a reward system, encouraging good behavior and discouraging problematic behavior. These programs are planned by certified behavior analysts and can be implemented by various healthcare professionals like physical therapists, psychologists, and speech therapists. Parents, teachers, and caretakers are also advised to follow these behavioral models at all times.
In environmental therapy, sensory experiences are amplified in a way to reduce symptoms seen in both autism and childhood disintegrative disorder.
In terms of medication, they are mostly used to manage symptoms as they manifest since there is no direct cure for this disorder. Antipsychotic medicines are used to address repetitive behaviors and aggression. For controlling aggressive behavior, serotonin reuptake inhibitors, stimulants, and other antipsychotics can be prescribed. However, it’s important to know that these neuroleptic medications have a significant risk of causing a dangerous condition called neuroleptic malignant syndrome. If the child develops seizures, then anticonvulsants can also be used.
What else can Autism Spectrum Disorder be?
In diagnosing developmental disorders or learning disabilities, there are several other conditions that doctors must rule out. These include:
- Poisoning from heavy metals such as mercury and lead
- Aminoacidurias, a group of rare genetic disorders
- Underactive thyroid (Hypothyroidism)
- Brain tumors
- Exposure to certain pesticides (Organophosphates)
- Uncommon types of seizure disorders
- HIV infection
- Schizophrenia in children
- Rare conditions such as glycogen storage disorders
- A disease that leads to progressive brain damage (Subacute sclerosing panencephalitis)
- Tuberous sclerosis, a disorder that leads to tumor growth in organs
- A type of rare and fatal brain disorder (Creutzfeldt-Jakob disease)
All these conditions can cause symptoms similar to learning disabilities, and it’s critical for doctors to thoroughly examine patients to ensure an accurate diagnosis.
What to expect with Autism Spectrum Disorder
The outlook for CDD, a subtype of ASD, is unfortunately quite poor and is generally worse compared to other ASD subtypes. Once individuals lose abilities due to CDD, those skills typically do not come back. In fact, only roughly 20% of children with CDD will communicate in full sentences again following their diagnosis.
When these patients become adults, the majority are either dependent on full-time caregivers or reside in care facilities. By around ten years old, most of their abilities are lost. While some limited improvement can be seen in a small number of cases, overall the prognosis is not positive. As the disease progresses, children with CDD develop long-term behavioral and cognitive impairments.
Consequently, intellectual capacity, independence, and adaptability/adjustment skills are significantly affected in most cases, often deteriorating to a severe mental disability. Throughout their life, affected children will usually require caregiver support.
Possible Complications When Diagnosed with Autism Spectrum Disorder
Epilepsy often develops in people with autism, and the risk of seizures becomes higher throughout childhood. This risk is particularly high during adolescence. Certain types of medications, such as SSRIs and neuroleptics, can lower the threshold for seizures, meaning they can make seizures more likely. So, these need to be used carefully. Although generally, people with autism are expected to have a normal lifespan, complications from epilepsy can cause an increase in mortality. In fact, the death rate among people with autism is twice that of the general population, mainly due to complications of epilepsy.
Preventing Autism Spectrum Disorder
When a child is diagnosed with autism or another chronic illness, it can greatly affect the entire family. They often deal with feelings of isolation, stress, and financial struggles. It’s helpful for families to express their experiences and emotions, as this can aid emotional coping. The goal should be to strengthen factors that help deal with these challenges, like improving communication and behavior management skills of the parents. It’s also important for parents to learn more about their child’s condition and understanding any developmental issues the child may have.
Connecting with other families going through the same experience can be very beneficial. Forming a supportive network, looking after their own well-being, and advocating for their child’s needs can also be incredibly helpful. Health care providers can play a key role in this process by recognizing the difficulties these parents are facing. They can facilitate connections between parents and promote a strong relationship between themselves and the families they are working with.
