IVIG For Enteroviral Meningoencephalitis: Is This Therapy Effective? 

Limited evidence supports the use of IVIG for enteroviral meningoencephalitis. However, considering that no standard treatment exists, IVIG may be an option, particularly in those with weakened immune systems. 

A Quick Overview of Enteroviral Meningoencephalitis

Enteroviral meningoencephalitis is a rare but potentially fatal condition. It occurs when certain types of non-polio enteroviruses cause swelling of both the brain and its coverings (meninges). 

Enteroviruses comprise many different types of viruses that usually cause mild infection. However, in people with compromised immune systems, infants, and children, they can cause severe symptoms. 

Examples of enteroviruses are coxsackieviruses, echoviruses, polioviruses, and the hepatitis A virus. These viruses can spread from one person to another via direct contact with viruses shed from the digestive tract or upper airway. 

Symptoms of enteroviral meningoencephalitis can include:

• Fever
• Headache
• Vomiting
• Neck stiffness
• Seizures
• Rashes
• Sudden, uncontrollable muscle contraction
• Changes of consciousness
• Coma

Though anyone can get enteroviral meningoencephalitis, newborns and people with weakened immune systems are at the highest risk. Symptoms in newborns can include:

• Fever
• Poor feeding
• Irritability
• Lethargy
• Jaundice (yellow discoloration of the skin and eyes)

How Effective Is IVIG For Enteroviral Meningoencephalitis?

Results can vary widely. 

Several case reports suggest IVIG can result in the complete resolution of symptoms. However, in some cases, IVIG is ineffective, followed by disease progression or even death.

Factors that may contribute to the outcome of IVIG for enteroviral meningoencephalitis include [1]:

• Delays in diagnosis 
• Differences in the amount of enteroviral antibodies (proteins) among IVIG preparations

Nonetheless, some researchers recommend high-dose IVIG as the first-line therapy for enteroviral meningoencephalitis [2].

IVIG For Enteroviral Meningoencephalitis: Recent Success Stories

In a 2023 case report, German researchers reported a case of full recovery in a 38-year-old male with long-term enterovirus meningoencephalitis. The patient had taken the cancer medication rituximab 4 years earlier, which the researchers believe could be one of the causes of enterovirus meningoencephalitis. 

The patient received 2g/kg body weight of IVIG in the beginning. After a few days of IVIG therapy, the symptoms improved, and the patient was able to walk. 

Later, the IVIG dose was reduced to 0.5g/kg body weight every 6 weeks. After 3 months, his physical and cognitive symptoms improved drastically. A full recovery was observed at follow-up 11 months after starting IVIG [3].

A similar success story was observed by American researchers in a 2021 study. This case involved a 37-year-old female who had enteroviral meningoencephalitis as a complication of rituximab therapy for rheumatoid arthritis [4].

At the time of admission, she had a fever, headache, confusion, and tremor. Diagnostic tests found her positive for enterovirus. She received IVIG 0.4g/kg daily for 5 days, and her symptoms (agitation, confusion, tremors, gait abnormalities, and headaches) improved significantly. 

Complete resolution of symptoms occurred over the next 12 months. 

Likewise, in a 2019 case report, a 46-year-old female with enteroviral meningoencephalitis taking rituximab for psoriatic arthritis was treated with IVIG 0.4g/kg/day for 5 days. After IVIG therapy, her symptoms improved, and she was discharged from the hospital. 

However, complete resolution of symptoms was not observed at the time of discharge [5].

Earlier Success Stories

In a 1981 case report published in the New England Journal of Medicine, investigators reported a 32-year-old man with a weakened immune system who fully recovered from echovirus-induced meningoencephalitis with high-dose modified IVIG [6].

In 1987, researchers at the Duke University Medical Center analyzed data of over 40 patients with chronic enteroviral meningoencephalitis. Most patients in this review had some form of immunodeficiency. 

According to researchers, IVIG can be considered an empirical treatment for chronic enteroviral meningoencephalitis [7]. Empirical treatment is the practice of using medication based on experience instead of precise knowledge of the causative factor or nature of a disease.

The Challenges of Using IVIG for Enteroviral Meningoencephalitis

Despite promising results in several case reports, the definitive benefits of IVIG for enteroviral meningoencephalitis have yet to be demonstrated in large trials. 

Unfortunately, there have been reports of symptom worsening and death following treatment of enteroviral meningoencephalitis with IVIG. 

For instance, a 2016 review analyzed 10 cases of rituximab-associated meningoencephalitis. Of the 10 patients, five received IVIG. Two patients who received IVIG died [8].

While death cannot be directly attributed to IVIG therapy, available evidence suggests that IVIG may not be a lifesaver in many cases. 

Other factors that limit IVIG use for enteroviral meningoencephalitis include:

• A lack of large, controlled human trials
• Insufficient knowledge about the effective dosage range
• Duration of therapy
• A lack of the precise mechanism of action of IVIG

Frequently Asked Questions

1. Is IVIG used for enterovirus encephalitis?

IVIG may be considered for enterovirus encephalitis in patients with weakened immune systems. According to a 2021 review, a high-dose approach (2 g/kg) may be more beneficial [9].

2. How do you treat enteroviral encephalitis?

Specific treatment is unavailable currently. Nonetheless, specific antiviral medications and IVIG may help improve treatment outcomes in individuals with enteroviral encephalitis.

3. What is the first-line treatment for encephalitis?

Most neurologists recommend oral or intravenous (IV) corticosteroids for initial therapy. IVIG or plasma exchange are potentially effective treatment options, especially when other treatments don’t work. 

4. How do you diagnose meningoencephalitis?

The primary diagnostic test for meningoencephalitis is CSF analysis. CSF analysis examines your cerebrospinal fluid (the fluid in and around the brain and spinal cord) to help diagnose diseases of the brain and spinal cord. 

5. What is the drug of choice for meningoencephalitis?

Depending on the cause and severity, your provider may prescribe medications, such as antiviral drugs, antiseizure drugs, or corticosteroids. 

6. What is IVIG used for in neurology?

IVIG is used in neurology to treat many conditions, including:

• GBS
• CIDP
• MMN
• Dermatomyositis
• Myasthenia gravis exacerbations
• Stiff-person syndrome
• Autoimmune epilepsy
• Neuromyelitis
• Autoimmune encephalitis

7. Encephalitis vs. meningoencephalitis: What’s the difference?

Encephalitis is inflammation (swelling) of the brain. Meningoencephalitis is simultaneous inflammation of the brain and its coverings.