Mollaret's meningitis

Mollaret's meningitis
Classification and external resources
Meninges of the central nervous system: dura mater, arachnoid, and pia mater.
ICD-9	047.9
eMedicine	neuro/697
MeSH	D008582

Mollaret's meningitis is a recurrent inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. It is a recurrent, benign, aseptic meningitis.

It is named for Pierre Mollaret.^[1][2]

Signs and symptoms

Mollaret's meningitis is characterized by recurrent episodes of severe headache, meningismus, and fever; cerebrospinal fluid (CSF) pleocytosis with large "endothelial" cells, neutrophils, and lymphocytes; and attacks separated by symptom-free periods of weeks to months; and spontaneous remission of symptoms and signs. Many people have side effects between bouts that vary from chronic daily headaches to after-effects from meningitis such as hearing loss. Some patients report short bouts of 3–7 days of being sick while others have cases that can last for weeks or months. Many references talk about brief acute cases but support groups of people with Mollaret's show a wide variety of lengths of each bout. Although historically Mollaret's meningitis did not have a causative agent, it is now believed to be mostly from herpetic infection.^[3] Some patients also report frequent shingles outbreaks.^{[citation needed]} The chickenpox virus is part of the herpes family.^[4] CNS epidermoid cysts can give rise to Mollaret's meningitis especially with surgical manipulation of cyst contents.

Diagnosis

Investigations include blood tests (electrolytes, liver and kidney function, inflammatory markers and a complete blood count) and usually X-ray examination of the chest. The most important test in identifying or ruling out meningitis is analysis of the cerebrospinal fluid (fluid that envelops the brain and the spinal cord) through lumbar puncture (LP). However, if the patient is at risk for a cerebral mass lesion or elevated intracranial pressure (recent head injury, a known immune system problem, localizing neurological signs, or evidence on examination of a raised ICP), a lumbar puncture may be contraindicated because of the possibility of fatal brain herniation. In such cases, a CT or MRI scan is generally performed prior to the lumbar puncture to exclude this possibility. Otherwise, the CT or MRI should be performed after the LP, with MRI preferred over CT due to its superiority in demonstrating areas of cerebral edema, ischemia, and meningeal inflammation.

During the lumbar puncture procedure, the opening pressure is measured. A pressure of over 180 mm H₂O is suggestive of bacterial meningitis.

Mollaret's meningitis is suspected based on clinical criteria and confirmed by HSV 1 or HSV 2 on PCR of CSF, although not all cases test positive.

Treatment

Initial treatment

Acyclovir is the treatment of choice for Mollaret's meningitis. Some patients see a drastic difference in how often they get sick and others don't. Often treatment means managing symptoms, such as pain management and strengthening the immune system.

See also

• Encephalitis
• Meningitis
• Herpes simplex virus

References

1. ^ synd/1537 at Who Named It?
2. ^ P. Mollaret. Méningite endothélio-leucocytaire multirécurrente bénigne. Syndrome nouveau ou maladie nouvelle? (Documents cliniques). Revue neurologique, Paris, 1944, 76: 57-76.
3. ^ Tarakad S Ramachandran, MBBS, FRCP(C), FACP (Feb 12, 2010). "Aseptic Meningitis". Emedicine. http://emedicine.medscape.com/article/1169489-overview. Retrieved 9 January 2011. 
4. ^ Mollaret's meningitis at patient.co.uk