Overview
Developmental and epileptic encephalopathy with spike-wave activation in sleep (DEE-SWAS) is a rare and serious brain condition that affects children. It is also sometimes called epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) or, when it mainly affects language, Landau-Kleffner syndrome. In this condition, the brain produces abnormal electrical activity — especially during sleep — that disrupts normal brain development. This unusual brain activity shows up on a test called an EEG (electroencephalogram) as continuous or near-continuous spike-wave patterns during non-REM sleep. The condition causes seizures, but the sleep-related brain activity is often what causes the most harm. Even without obvious seizures at night, the abnormal electrical bursts during sleep interfere with learning, memory, behavior, and language. Children may regress — meaning they lose skills they had already learned, such as speech or coordination. Treatment focuses on reducing the abnormal brain activity, especially during sleep, using anti-seizure medications, steroids, or other therapies. While there is no cure, early and aggressive treatment can help protect brain development and improve quality of life. The condition often improves after puberty, but many children are left with lasting learning or behavioral challenges.
Also known as:
Key symptoms:
Seizures, often occurring during sleepLoss of previously learned language or speech skillsLearning difficulties and intellectual regressionAttention problems and hyperactivityBehavioral changes such as aggression or mood swingsMemory problemsDifficulty understanding spoken languagePoor coordination or clumsinessSleep disturbancesDrooling or difficulty swallowing in some casesSocial withdrawal or autism-like behaviors
Clinical phenotype terms (30)— hover any for plain English
Variable
Can be inherited in different ways depending on the underlying gene
Childhood
Begins in childhood, roughly ages 1 to 12
FDA & Trial Timeline
4 eventsHugo W. Moser Research Institute at Kennedy Krieger, Inc. — PHASE2
East Suffolk and North Essex NHS Foundation Trust
Children's Mercy Hospital Kansas City — NA
University Hospital, Strasbourg, France — NA
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Developmental and epileptic encephalopathy with spike-wave activation in sleep.
2 clinical trialsare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Developmental and epileptic encephalopathy with spike-wave activation in sleep.
Community
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Start the conversation →Latest news about Developmental and epileptic encephalopathy with spike-wave activation in sleep
Disease timeline:
New recruiting trial: Sleep Related Memory Consolidation in Children With Age Related Focal Epilepsy.
A new clinical trial is recruiting patients for Developmental and epileptic encephalopathy with spike-wave activation in sleep
New recruiting trial: Repeated Oscillatory TMS Therapy of the Epileptogenic Cortical Area in Children With Focal CSWS
A new clinical trial is recruiting patients for Developmental and epileptic encephalopathy with spike-wave activation in sleep
New recruiting trial: Study of Patients with Electrical Status Epilepticus in Sleep
A new clinical trial is recruiting patients for Developmental and epileptic encephalopathy with spike-wave activation in sleep
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.What is causing my child's condition — has a genetic cause been found?,How often should my child have EEG monitoring, and what are we looking for?,Which medication or treatment do you recommend first, and what are the side effects?,When should we consider steroids, and what are the risks?,What signs should prompt me to call you or go to the emergency room?,What educational and therapy supports should my child have right now?,Is there a chance my child's condition will improve after puberty, and what can we do to protect their development in the meantime?
Common questions about Developmental and epileptic encephalopathy with spike-wave activation in sleep
What is Developmental and epileptic encephalopathy with spike-wave activation in sleep?
Developmental and epileptic encephalopathy with spike-wave activation in sleep (DEE-SWAS) is a rare and serious brain condition that affects children. It is also sometimes called epileptic encephalopathy with continuous spike-and-wave during sleep (CSWS) or, when it mainly affects language, Landau-Kleffner syndrome. In this condition, the brain produces abnormal electrical activity — especially during sleep — that disrupts normal brain development. This unusual brain activity shows up on a test called an EEG (electroencephalogram) as continuous or near-continuous spike-wave patterns during non
At what age does Developmental and epileptic encephalopathy with spike-wave activation in sleep typically begin?
Typical onset of Developmental and epileptic encephalopathy with spike-wave activation in sleep is childhood. Age of onset can vary across affected individuals.
Are there clinical trials for Developmental and epileptic encephalopathy with spike-wave activation in sleep?
Yes — 2 recruiting clinical trials are currently listed for Developmental and epileptic encephalopathy with spike-wave activation in sleep on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Developmental and epileptic encephalopathy with spike-wave activation in sleep?
3 specialists and care centers treating Developmental and epileptic encephalopathy with spike-wave activation in sleep are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.