ICD-10-CM Diagnosis Code G04.02 - Postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis (original) (raw)

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Postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis

ICD-10-CM Code:

G04.02

ICD-10 Code for:

Postimmun ac dissem encphlts, myelitis and encephalomyelitis

Is Billable?

Yes - Valid for Submission

Chronic Condition Indicator: [1]

Not chronic

Code Navigator:

G04.02 is a billable diagnosis code used to specify a medical diagnosis of postimmunization acute disseminated encephalitis, myelitis and encephalomyelitis. The code is valid during the current fiscal year for the submission of HIPAA-covered transactions from October 01, 2025 through September 30, 2026.

  1. Code Information
  2. Approximate Synonyms
  3. Clinical Classification
  4. Tabular List of Diseases and Injuries
  5. Index to Diseases and Injuries References
  7. Convert to ICD-9 Code
  8. Patient Education
  9. Other Codes Used Similar Conditions
  10. Code History

The following list of clinical terms are approximate synonyms, alternative descriptions, or common phrases that might be used by patients, healthcare providers, or medical coders to describe the same condition. These synonyms and related diagnosis terms are often used when searching for an ICD-10 code, especially when the exact medical terminology is unclear. Whether you're looking for lay terms, similar diagnosis names, or common language alternatives, this list can help guide you to the correct ICD-10 classification.

Clinical Classifications group individual ICD-10-CM diagnosis codes into broader, clinically meaningful categories. These categories help simplify complex data by organizing related conditions under common clinical themes.

They are especially useful for data analysis, reporting, and clinical decision-making. Even when diagnosis codes differ, similar conditions can be grouped together based on their clinical relevance. Each category is assigned a unique CCSR code that represents a specific clinical concept, often tied to a body system or medical specialty.

CCSR Code: NVS002

Inpatient Default: Y - Yes, default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: Y - Yes, default outpatient assignment for principal diagnosis or first-listed diagnosis.

CCSR Code: FAC016

Inpatient Default: N - Not default inpatient assignment for principal diagnosis or first-listed diagnosis.

Outpatient Default: N - Not default outpatient assignment for principal diagnosis or first-listed diagnosis.

The following annotation back-references for this diagnosis code are found in the injuries and diseases index. The Index to Diseases and Injuries is an alphabetical listing of medical terms, with each term mapped to one or more ICD-10-CM code(s).

References found for this diagnosis code in the External Cause of Injuries Index:

Below are the ICD-9 codes that most closely match this ICD-10 code, based on the General Equivalence Mappings (GEMs). This ICD-10 to ICD-9 crosswalk tool is helpful for coders who need to reference legacy diagnosis codes for audits, historical claims, or approximate code comparisons.

ICD-9-CM: 323.51

Approximate Flag - The approximate mapping means this ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option, but it may not fully capture the original diagnosis or clinical intent.

ICD-9-CM: 323.52

Approximate Flag - The approximate mapping means this ICD-10 code does not have an exact ICD-9 equivalent. The matched code is the closest available option, but it may not fully capture the original diagnosis or clinical intent.

Encephalitis

What is encephalitis?

Encephalitis is inflammation (swelling) of the brain. It can happen when an infection or medical condition that affects the brain activates your immune system. The inflammation can cause a wide range of symptoms. In extreme cases, it can lead to brain damage, stroke, or even death.

What causes encephalitis?

There are different types of encephalitis, based on what the cause is. The two main types are infectious encephalitis and autoimmune encephalitis.

Infectious encephalitis is usually caused by a virus. In fact, viruses are the most common cause of encephalitis. Some of the different viruses that cause it include:

Bacteria, fungi, and parasites can also cause infectious encephalitis. But this is not common.

Autoimmune encephalitis happens when your immune system mistakenly attacks healthy brain cells. It can be triggered by conditions such as certain cancers, benign tumors, and infections. Sometimes the cause is not known.

Who is more likely to get encephalitis?

Anyone can get encephalitis, but you are more likely to get it if you:

What are the symptoms of encephalitis?

The symptoms of encephalitis can vary a lot, depending on how severe it is. Many people do not have any symptoms. Others may have mild flu-like symptoms such as fever, fatigue, headache, or body aches. If encephalitis becomes more serious, it can cause:

Encephalitis can be dangerous in infants. Their symptoms may include:

If you or your child is having symptoms of encephalitis, it's important to get medical care right away.

How is encephalitis diagnosed?

To find out if you have encephalitis, your health care provider:

What are the treatments for encephalitis?

Most people with encephalitis will need treatment in the hospital. Depending on the cause, treatments may include antiviral medicines, antibiotics, corticosteroids, and other medicines.

For some types of encephalitis, there is no medicine to treat it. But rest, nutrition, and fluids can help your body fight the infection and relieve symptoms.

Some people may need physical, speech, and occupational therapy once the illness is under control.

Can encephalitis be prevented?

There are steps you can take to help prevent encephalitis that is caused by infections:

NIH: National Institute of Neurological Disorders and Stroke

[Learn More in MedlinePlus]

Spinal Cord Diseases

Your spinal cord is a bundle of nerves that runs down the middle of your back. It carries signals back and forth between your body and your brain. It is protected by your vertebrae, which are the bone disks that make up your spine. If you have an accident that damages the vertebrae or other parts of the spine, this can also injure the spinal cord. Other spinal cord problems include:

Symptoms vary but might include pain, numbness, loss of sensation and muscle weakness. These symptoms can occur around the spinal cord, and also in other areas such as your arms and legs. Treatments often include medicines and surgery.

[Learn More in MedlinePlus]