Short answer · Medically reviewed summary · Last updated: 2026-05-08
Rasmussen’s encephalitis is classified under the ICD-10 code G04.81 (Other encephalitis, myelitis, and encephalomyelitis). In the older ICD-9-CM classification system, Rasmussen’s encephalitis is typically coded as 323.81, which specifically denotes other causes of encephalitis. What is the clinical presentation of Rasmussen’s encephalitis? Rasmussen’s encephalitis is a rare, progressive inflammatory neurological disorder characterized by chronic focal epilepsy, cognitive decline, and progressive neurological deficits.
ICD10 code of Rasmussen's encephalitis and ICD9 code
ICD-10 and ICD-9 codes for Rasmussen's encephalitis, with classification details for clinicians, coders and patients.
Rasmussen’s encephalitis is classified under the ICD-10 code G04.81 (Other encephalitis, myelitis, and encephalomyelitis). In the older ICD-9-CM classification system, Rasmussen’s encephalitis is typically coded as 323.81, which specifically denotes other causes of encephalitis.
What is the clinical presentation of Rasmussen’s encephalitis?
Rasmussen’s encephalitis is a rare, progressive inflammatory neurological disorder characterized by chronic focal epilepsy, cognitive decline, and progressive neurological deficits. It primarily affects children, though it can occur in adults. The condition often presents with epilepsia partialis continua, a state of persistent focal motor seizures that are notoriously difficult to control with standard anti-seizure medications.
How is Rasmussen’s encephalitis diagnosed?
Diagnosis of Rasmussen’s encephalitis relies on a combination of clinical, electroencephalographic (EEG), and neuroimaging findings. Because there is no single biomarker for the disease, clinicians look for the following criteria:
- Progressive focal neurological deficits (such as hemiparesis or hemianopia).
- Focal cortical seizures or epilepsia partialis continua.
- Unilateral cortical atrophy observed on serial MRI scans.
- EEG evidence of focal slowing and seizure activity originating from one hemisphere.
Is Rasmussen’s encephalitis hereditary?
Current medical research indicates that Rasmussen’s encephalitis is not considered an inherited or genetic disorder. While the exact etiology remains a subject of intense study, the prevailing theory is that it is an immune-mediated process. The body’s own immune system appears to target brain cells, leading to chronic inflammation and tissue damage within one cerebral hemisphere.
What is the impact of the Rasmussen’s encephalitis community?
Living with a rare diagnosis can feel isolating. At DiseaseMaps.org, 14 people with Rasmussen’s encephalitis have already joined our community to share their experiences and support one another. Connecting with others who understand the complexities of managing this condition can provide vital emotional relief and practical insights into navigating long-term treatment plans.
Next steps
- Consult a pediatric neurologist or an epileptologist specializing in inflammatory brain diseases.
- Discuss advanced treatment options such as immunotherapy or functional hemispherectomy with your medical team.
- Connect with the 14 members of the DiseaseMaps.org community to share lived experiences.
- Monitor for any changes in seizure frequency or cognitive function and report them to your specialist immediately.
Medical disclaimer: This content is for informational purposes only and does not constitute professional medical advice, diagnosis, or treatment.
References
- Orphanet: Rasmussen encephalitis (ORPHA:1301)
- NIH GARD: Rasmussen's encephalitis (GARD ID: 7522)
- PubMed: Clinical diagnostic criteria for Rasmussen's encephalitis (PMID: 15657335)
- OMIM: Rasmussen encephalitis (Entry #608537)
