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Everything To Know About Mollaret's Meningitis

Mollaret's meningitis is a rare type of meningitis that causes recurring episodes of inflammation around the brain and spinal cord.

Mollaret's meningitis is a rare and chronic form of aseptic (nonbacterial) meningitis, involving recurrent episodes of meningitis-like symptoms, including severe headaches, fever, and neck stiffness. Its other names include benign recurrent lymphocytic meningitis and idiopathic recurrent meningitis.

Unlike bacterial meningitis, this condition does not result from bacteria but rather from viral infections, particularly herpes simplex virus type 2 (HSV-2). HSV-2 is commonly known for causing genital herpes. In rare cases, it can also lead to recurrent meningitis, where the virus affects the meninges — the protective membranes around the brain and spinal cord.

While these episodes can be severe, they typically resolve independently after a few days with supportive care. However, doctors may opt to prescribe antiretroviral treatments.

This article covers Mollaret's meningitis, including its symptoms, causes, and treatment options.

Mollaret's meningitis is a rare form of aseptic, recurrent meningitis primarily linked to viral infections, particularly HSV-2. It was first described by Dr. Pierre Mollaret in 1944.

The condition occurs when the virus directly infects the central nervous system and remains dormant for extended periods without causing symptoms. When the infection reactivates, it triggers recurrent episodes of meningitis-like symptoms.

Approximately 1 in 5 people who develop HSV-2 meningitis experience recurrences. When symptoms occur more than three times, the condition is Mollaret's meningitis.

Unlike bacterial meningitis, which requires antibiotics, Mollaret's meningitis usually resolves independently and is not life threatening. However, the condition's recurrent nature can lead to significant discomfort, even though it does not typically cause long-term damage.

Mollaret's meningitis most commonly results from viral infections with HSV-2, although other viral agents such as HSV-1 and Epstein-Barr virus (EBV) may also contribute. The virus can remain dormant in the body and reactivate intermittently, causing recurrent episodes of inflammation in the meninges.

Other potential triggers include intracranial cystic anomalies. These fluid-filled sacs develop within the brain or skull due to congenital conditions, infections, or trauma. They may release irritant material into the meninges and provoke a hypersensitivity reaction. Certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs), may also have this effect.

Additionally, immune system deficiencies may predispose individuals to recurrent viral infections, leading to meningitis. Certain autoimmune disorders, such as lupus, also link to Mollaret's meningitis. However, Mollaret's meningitis is idiopathic, meaning its cause remains unknown.

Treatment for Mollaret's meningitis depends on the underlying cause, the symptoms' severity, and the recurrence frequency.

Healthcare professionals may prescribe antiviral medications, such as acyclovir or valacyclovir, to suppress herpes virus activity. These medications can reduce the frequency and severity of attacks in patients with HSV-related Mollaret's meningitis.

In other cases, treatment focuses on symptom management, using pain relievers, anti-inflammatory drugs, and fluids to alleviate headaches, fever, and discomfort.

Hospitalization may be necessary if symptoms are severe or there is concern about the possibility of bacterial meningitis.

There is no guaranteed method to prevent Mollaret's meningitis entirely, but reducing the risk of viral infections, particularly HSV, could help. That said, only a small proportion of those with HSV-2 will develop Mollaret's meningitis.

Practicing good hygiene, avoiding contact with individuals experiencing active herpes lesions, and managing immune health may lower the risk of triggering an episode.

In some cases, doctors may recommend suppressive viral therapy with acyclovir to prevent recurrences.

Mollaret's meningitis is a rare and recurrent form of viral meningitis that can cause significant discomfort through repeated episodes of headache, fever, and neck stiffness. Although the condition is not life threatening, it can affect a person's quality of life.

Timely diagnosis, treatment with antivirals, and symptom management can help people manage the condition and may reduce the frequency of attacks.

Individuals with meningitis symptoms should consult a healthcare professional to explore treatment options and rule out serious causes.

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