2025 ICD-10-CM code G04.0
(Active) Effective Date: N/A Revision Date: N/A Neurological Disorders - Inflammatory diseases of the central nervous system Chapter VI: Diseases of the nervous system (G00-G99) Feed
Acute disseminated encephalomyelitis (ADEM) is a rare inflammatory demyelinating disorder affecting the brain and spinal cord, often following an infection.
Not applicable to ICD-10 codes. Modifiers are used with procedural codes (CPT/HCPCS).
Medical necessity for ADEM treatment is established by the presence of clinical symptoms, neurological examination findings, and imaging evidence consistent with the diagnosis. The treatment is aimed at reducing the inflammatory process, preventing further neurological damage, and facilitating recovery.Medical necessity may be challenged if alternative explanations for the findings are not sufficiently considered or if the treatment plan is not clinically appropriate given the severity of the case.
Neurologists and other specialists in the field of neurology are primarily responsible for the diagnosis and management of ADEM.Responsibilities include obtaining detailed medical history, neurological examination, ordering and interpreting diagnostic tests (MRI, CSF analysis, blood tests), initiating treatment, monitoring patient response, providing appropriate rehabilitative care, and ongoing follow-up to assess recovery and address any residual symptoms.
- Chapter VI: Diseases of the nervous system (G00-G99)
- G00-G09 (Inflammatory diseases of the central nervous system)
In simple words: ADEM is a rare brain and spinal cord disorder causing sudden inflammation.It often happens after an infection like a cold or the flu.Symptoms include headache, fever, weakness, numbness, vision problems, and difficulty walking.Treatment focuses on reducing inflammation with medications like steroids.
Acute disseminated encephalomyelitis (ADEM) is an acquired inflammatory demyelinating syndrome primarily affecting the brain and spinal cord's white matter in a multifocal distribution.It presents with a subacute onset of encephalopathy accompanied by polyfocal neurological signs and symptoms.ADEM may mimic other acute demyelinating syndromes, particularly multiple sclerosis (MS), but is distinguishable through clinical features, neuroimaging, and laboratory findings.The onset often follows a prodromal illness (fever, malaise, headache, respiratory or gastrointestinal symptoms) in over half of cases.ADEM is typically monophasic in prepubertal children, unlike the relapsing-remitting nature of MS in young adults.Diagnostic tests include MRI, lumbar puncture (CSF analysis), and blood tests to identify infectious triggers or MOG antibodies (present in over half of pediatric cases).
Example 1: A 7-year-old boy presents with fever, headache, and unsteady gait a week after recovering from the flu. MRI reveals multifocal white matter lesions.Diagnosis: ADEM. Treatment: High-dose intravenous methylprednisolone., A 12-year-old girl develops sudden vision changes, weakness, and numbness in her limbs following a bout of measles.Neurological exam and MRI are consistent with ADEM. Treatment: Intravenous immunoglobin (IVIG) therapy., An 8-year-old boy presents with seizures, altered consciousness, and weakness after a viral infection. CSF analysis shows lymphocytic pleocytosis. MRI demonstrates extensive white matter demyelination. Diagnosis: severe ADEM. Treatment: Intensive care, corticosteroids, and supportive care.This case has higher risk of residual symptoms.
* Detailed medical history including recent infections or vaccinations.* Thorough neurological examination documenting neurological deficits.* Results of brain MRI showing multifocal white matter lesions.* Cerebrospinal fluid (CSF) analysis results (cell count, protein levels, glucose).* Blood tests (complete blood count, inflammatory markers, serological testing for infectious agents, MOG antibody testing).* Documentation of treatment administered (corticosteroids, IVIG, plasmapheresis) and response.* Progress notes detailing clinical course, response to treatment, and any residual neurological deficits.
** ADEM is a diagnosis of exclusion. Other conditions such as multiple sclerosis (MS) or acute viral encephalitis must be ruled out before assigning the G04.0 code.The prognosis is generally good with most children making a full or near-full recovery.However, some may experience long-term neurological deficits.
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- Modifier TC rule: Not applicable to ICD-10 codes. TC modifiers apply to procedural codes.
- Specialties:Neurology, Pediatric Neurology
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