One of the key points in
understanding "autism" is that it is not a single biological condition.
It is just a behavioral diagnosis based on observed developmental patterns
involving language, social communication, repetitive behaviors and sensory
differences.
That means very different biological
conditions can produce children/adults who all outwardly appear some version of “autistic.”
A striking example of this was
recently shared with me by one of our readers.
A Child Diagnosed
with "autism"
The parents noted severe
developmental regression accompanied by unusual sleep disturbances and night
terrors. Over time they also observed something very interesting, that changes
in valproic acid (VPA) dosing appeared to significantly affect symptoms.
Their neurologist had performed EEGs
which reportedly showed abnormalities and yet despite this, no further major
investigations were ordered:
- no epilepsy-protocol MRI
- no prolonged 24-hour EEG
- and no comprehensive workup for epileptic
encephalopathy.
Meanwhile, the family pursued
extensive genetic testing searching for answers.
This is unfortunately an
increasingly familiar story in developmental medicine, a child receives
a behavioral autism diagnosis, and the diagnostic process effectively stops
there.
Seeking a second opinion
The family eventually attended a
specialized pediatric neurology clinic at a major children’s hospital.
The difference was immediate.
After
reviewing EEGs, videos before regression, videos after regression and
recordings of the child’s sleep terrors, the specialists concluded that the
child fit the modern framework of:
DEE-SWAS
(Developmental and Epileptic Encephalopathy with Spike-and-Wave Activation in
Sleep)
The older terms for overlapping
conditions include:
- ESES (Electrical Status Epilepticus in
Sleep)
- CSWS (Continuous Spike-Wave During Sleep)
- Landau-Kleffner syndrome
The clinic immediately ordered:
- epilepsy-protocol MRI
- prolonged 24-hour EEG
- metabolic investigations
- ophthalmologic evaluation
- orthopedic assessment
Most strikingly, they reportedly
stated that this looked like:
“DEE-SWAS masquerading as autism.”
What Is DEE-SWAS?
DEE-SWAS is increasingly understood as
a disorder of abnormal brain network synchronization during sleep.
The key issue is not simply seizures.
In many children, pathological
spike-wave activity during deep non-REM sleep may interfere with:
- language development
- memory consolidation
- emotional regulation
- cognition
- attention
- and developmental plasticity itself.
Some primarily present with:
- regression
- loss of speech
- autistic behaviors
- sensory abnormalities
- emotional dysregulation
- fluctuating cognition
- sleep disturbance
- night terrors.
In many cases, the child outwardly
appears to have classic regressive autism.
Why night terrors matter
Night terrors are usually benign in
ordinary children.
However, in the context of
- developmental regression
- abnormal EEGs
- fluctuating cognition
- or epileptiform activity
they become much more significant.
DEE-SWAS specifically affects deep
slow-wave sleep — the same sleep stage associated with night terrors and
abnormal arousal phenomena.
This does not mean every child with
night terrors has epileptic encephalopathy.
But regression plus unusual sleep
phenomena should raise suspicion that a prolonged sleep EEG may be warranted.
Treating the EEG to treat the child
One of the most interesting concepts
in modern DEE-SWAS research is:
“Treating the EEG to treat the
patient.”
The concern is that the abnormal sleep
spike-wave activity itself may drive the developmental deterioration.
Treatments used include:
- valproic acid
- clobazam
- clonazepam
- steroids
- ketogenic diet
- acetazolamide (Diamox)
- ethosuximide
- and in some cases surgery.
Ethosuximide is particularly
interesting because it is a T-type calcium channel blocker that affects
thalamocortical spike-wave synchronization.
The thalamus appears to play a major
role in generating these pathological sleep oscillations.
Ketogenic therapies and ketone esters
are also fascinating because they may:
- stabilize neuronal metabolism
- reduce hyperexcitability
- alter glutamate/GABA balance
- and improve network stability during
sleep.
For more
information on treatment:
Treatment of Developmental/Epileptic Encephalopathy With Spike-Wave Activation in Sleep
Is DEE-SWAS Rare?
Officially, yes. But many experts
suspect it is significantly under-recognized.
Why? Because many children with:
- regression
- autism
- language loss
- or sleep problems
never
receive a prolonged sleep EEG monitoring.
A short daytime EEG may miss much of
the pathology.
This is especially important because
some children may improve substantially when the abnormal sleep-related
epileptiform activity is treated.
Autism is just a behavioral
phenotype
Cases like this reinforce an
increasingly important idea.
“Autism” represents a common
behavioral phenotype arising from many different biological mechanisms.
For one child:
- synaptic dysfunction may dominate.
For another:
- mitochondrial dysfunction.
For another:
- immune dysregulation.
And for another:
- sleep-activated epileptiform
encephalopathy.
The behavioral presentation may look
similar, while the biology underneath is profoundly different. The treatment
will also be different, although there are surprising overlaps.
Conclusion
DEE-SWAS is not just a case of a bad night’s sleep.
The concern
is months or years of abnormal electrical activity repeatedly disrupting the
brain during one of its most critical developmental states.
In DEE-SWAS
the brain spends large portions of deep sleep in a pathological synchronized
firing mode instead of normal developmental processing.
Over time
this may interfere with language acquisition, cognition, emotional regulation
and developmental plasticity itself, potentially leading to developmental
regression and a child who outwardly appears to have regressive autism.
This post is not suggesting that most regressive autism is actually DEE-SWAS, but some clearly is.
However, children with:
- clear regression
- fluctuating abilities
- sleep deterioration
- night terrors
- language loss
- episodic worsening
- or unusual EEG findings
deserve more extensive neurological investigation than they often receive.
The father who contacted me persisted
despite initial dismissal and eventually reached a centre experienced in
developmental epileptic encephalopathies.
That persistence may prove extremely
important for their child’s future outcome.
That is why it’s incredibly important to investigate. Autism diagnosis is like a diagnosis of fever- you donot just plaster fever with paracetamol but you try find the cause of fever. Unfortunately, ND notion is harming young children as health authorities have used this term to write them off all responsibility. I hope you can guess that I am in U.K.
ReplyDeleteIt is difficult for a publicly funded healthcare system to investigate every child with autism in depth, because there are so many possible biological causes of developmental impairment. Hundreds of rare genetic, metabolic, neurological, and epileptic disorders can present with autistic features, and many are individually uncommon enough that they are not routinely considered.
DeleteAs autism diagnoses have increased, the challenge has become even greater. Comprehensive investigation of every case would require substantial specialist resources, time, and funding. In practice, many public healthcare systems do nothing.
In the UK, the private sector remains relatively small compared with some other countries, and most clinicians work within tightly defined evidence-based guidelines. While these guidelines help ensure consistency and patient safety, they can also make it difficult to pursue unconventional hypotheses or emerging treatments. As a result, autism is still largely approached as a lifelong neurodevelopmental condition rather than a disorder with potentially identifiable and treatable biological subtypes.
Please, which clinic was able to diagnose DEE-SWAS ?
DeleteAny pediatric epilepsy clinic at a major Children's Hospital can offer a 24 hour EEG, often with video monitoring. This data, with some background information, is sufficient to diagnose DEE-SWAS.
DeleteThe problem is that if your child has not had a seizure how would you access the epilepsy clinic?
A 24 hour EEG is probably a good idea for all severe autism. There are other issues other than DEE-SWAS that can be detected and are treatable.
The issue is the cost of the investigation and most public health systems have to restrict access due to budgetary constraints. If you can afford to pay yourself then it should be easier.
In the UK, for example, Great Ormond Street Children’s Hospital can diagnose DEE-SWAS. In the US I expect 24 hour EEG is widespread.
Do a private sleep-drived EEG, it takes about an hour and should not cost much. Then have a neurologist assess it and calculate the Spike Wave Index. If its greater than 50% then any specialized neurological clinic should proceed with further testing for diagnozing DEE-SWAS.
DeleteMy child has regressive autism. And a very bad EEG — abnormal waves during sleep up to 60% of the time. But what’s the point? In our country, they don’t prescribe anti-epileptic drugs if there are no epileptic seizures. And there are none. They say: 'We don’t treat the EEG — we treat the child. No seizures, no medication.'"
ReplyDeleteI understand your frustration. If abnormal sleep EEG activity isn't important in the absence of seizures, then why perform the EEG in the first place?
DeleteA child with regression and epileptiform activity during sleep 60% of the time is not a straightforward case. Different specialists have very different views on whether treatment is appropriate when there are no obvious seizures.
If possible, I would consider seeking a second opinion from a pediatric epileptologist or a center with experience in DEE-SWAS/ESES. Even if they ultimately recommend no treatment, they may offer a different perspective on the significance of the EEG findings and their potential impact on development.
How seizures were ruled out? Besides the DEE-SWAS spectrum, there are others forms of epilepsy which may or may not have obvious seizures. A very good example is frontal lobe epilepsy which may manifest as very brief episodes like "bizzare" sudden kind of behavior, explosive episodes and weird movements and vocalizations.
DeleteIt is is highly treatable with anti-seizure medications, even surgery. If you don't get EEG, MRI and metabolic workup, you cannot rule out anything.
This is established modern pediatric neurology, not some fringe theories.
My daughter's EEG showed just rare spikes at transition points from wakefulness to sleep during the sleep cycle. Her neurologist wasn't concerned, but she went on to have a seizure 6 months after the EEG.
ReplyDeletePeter, do you (or readers) know if an EEG in kids who have seizures is generally "worse" than rare spikes?
My daughter has regressive autism, but since her EEG is so far from the CSWS type, I suspect the spikes are more a symptom of some underlying instability than a cause. Still, it does seem she has seem some (non dramatic) improvements since starting an AED a year ago.
Grace
Grace, thanks for sharing your daughter's experience. One important point is that EEG findings and seizure risk do not always correlate in a straightforward way. Some children who later develop seizures have only rare epileptiform spikes on EEG, while others may have much more frequent abnormalities and never develop clinical seizures.
DeleteA single EEG is only a snapshot in time, and epileptiform activity can vary considerably depending on sleep stage, age, medications, and the underlying neurological condition. For that reason, relatively mild EEG findings do not completely rule out the possibility of future seizures.
Regarding regression and autism, many clinicians distinguish between EEG abnormalities that are likely contributing directly to cognitive or behavioral problems (such as in Continuous Spike-Wave During Sleep) and EEG abnormalities that may simply reflect an underlying brain vulnerability. When spikes are limited to rare discharges during sleep transitions, it is often difficult to determine whether they are causally related to symptoms.
Another complicating factor is that anti-seizure medications can have effects beyond seizure control. For example, valproate enhances GABAergic signaling, while drugs used for absence seizures can influence broader network dynamics and excitatory/inhibitory balance.
It is also worth noting that many, though far from all, parents report improvements in autism-related symptoms after starting anti-seizure medication. These reported changes can include gains in language, attention, social engagement, sleep, or behavior. However, responses are highly variable, and it remains unclear whether such improvements result from reducing epileptiform activity, preventing seizures, improving overall network stability, or other mechanisms.
Your daughter's experience is a good reminder that EEG findings are only one piece of the puzzle, and that both seizures and treatment responses can be more complex than the EEG alone might suggest.