Mollaret's meningitis | |
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Other names | Benign recurrent lymphocytic meningitis |
Meninges of the central nervous system: dura mater, arachnoid, and pia mater. | |
Specialty | Neurology |
Mollaret's meningitis is a recurrent or chronic inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. Since Mollaret's meningitis is a recurrent, benign (non-cancerous), aseptic meningitis, it is also referred to as benign recurrent lymphocytic meningitis. [1] [2] It was named for Pierre Mollaret, the French neurologist who first described it in 1944. [3] [4]
Although chronic meningitis has been defined as "irritation and inflammation of the meninges persisting for more than 4 weeks being associated with pleocytosis in the cerebrospinal fluid", [2] cerebrospinal fluid abnormalities may not be detectable for the entire time. [5] Diagnosis can be elusive, as Helbok et al. note: "in reality, many more weeks, even months pass by until the diagnosis is established. In many cases the signs and symptoms of chronic meningitis not only persist for periods longer than 4 weeks, they even progress with continuing deterioration, i. e. headache, neck stiffness and even low grade fever. Impairment of consciousness, epileptic seizures, neurological signs and symptoms may evolve over time." [2]
Mollaret's meningitis is characterized by chronic, recurrent episodes of headache, stiff neck, meningismus, and fever; cerebrospinal fluid (CSF) pleocytosis with large "endothelial" cells, neutrophil granulocytes, and lymphocytes; and attacks separated by symptom-free periods of weeks to years; 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 and visual impairment, nerve pain and twitches. Symptoms may be mild or severe. [2] Some cases may be short, lasting only 3–7 days, while others last for weeks to months.[ citation needed ]
While herpes simplex and varicella can cause rash, Mollaret's patients may or may not have a rash. [6] Herpes simplex virus is likely the most common cause of Mollaret's meningitis. [7]
Although for a long time, the cause of Mollaret's meningitis was not known, recent work has associated this problem with herpes simplex viruses, particularly HSV-2. [5] [8]
Cases of Mollaret's resulting from varicella zoster virus infection, diagnosed by polymerase chain reaction (PCR), have been documented. In these cases, PCR for herpes simplex was negative. [9] [10] Some patients also report frequent shingles outbreaks.[ citation needed ] Varicella zoster virus, which causes chickenpox and shingles is part of the herpes family, and is sometimes called "herpes zoster virus". [11] CNS epidermoid cysts (a type of cholesteatoma) can give rise to Mollaret's meningitis especially with surgical manipulation of cyst contents.[ citation needed ]
A familial association, where more than one family member had Mollaret's, has been documented. [12]
Diagnosis starts by examining the patient's symptoms. Symptoms can vary. Symptoms can include headache, sensitivity to light, neck stiffness, nausea, and vomiting. In some patients, fever is absent. Neurological examination and MRI can be normal. [5]
Mollaret's meningitis is suspected based on symptoms, and can be confirmed by HSV 1 or HSV 2 on PCR of Cerebrospinal fluid (CSF), although not all cases test positive on PCR. PCR is performed on spinal fluid or blood, however, the viruses do not need to enter the spinal fluid or blood to spread within the body: they can spread by moving through the axons and dendrites of the nerves. [13]
During the first 24 h of the disease the spinal fluid will show predominant polymorphonuclear neutrophils and large cells that have been called endothelial (Mollaret's) cells. [14]
A study performed on patients who had diffuse symptoms, such as persistent or intermittent headaches, concluded that although PCR is a highly sensitive method for detection, it may not always be sensitive enough for identification of viral DNA in CSF, due to the fact that viral shedding from latent infection may be very low. The concentration of viruses in CSF during subclinical infection might be very low. [15]
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.[ citation needed ]
During the lumbar puncture procedure, the opening pressure is measured. A pressure of over 180 mm H2O is suggestive of bacterial meningitis.
It is likely that Mollaret meningitis is underrecognized by physicians, and improved recognition may limit unwarranted antibiotic use and shorten or eliminate unnecessary hospital admission. [12]
PCR testing has advanced the state of the art in research, but PCR can be negative in individuals with Mollaret's, even during episodes with severe symptoms. For example, Kojima et al. published a case study for an individual who was hospitalized repeatedly, and who had clinical symptoms including genital herpes lesions. However, the patient was sometimes negative for HSV-2 by PCR, even though his meningitis symptoms were severe. Treatment with acyclovir was successful, indicating that a herpes virus was the cause of his symptoms. [16]
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.[ citation needed ]
The IHMF recommends that patients with benign recurrent lymphocytic meningitis receive intravenous acyclovir in the amount of 10 mg/kg every 8 hours, for 14–21 days. More recently, the second-generation antiherpetic drugs valacyclovir and famciclovir have been used to successfully treat patients with Mollaret's. Additionally, it has been reported that Indomethacin administered in the amount of 25 mg 3 times per day after meals, or 50 mg every 4 hours, has resulted in a faster recovery for patients, as well as more extended symptom-free intervals, between episodes. [1]
Recurring Mollaret meningitis attacks generally resolve within 3 to 5 years after the first occurrence, but some patients live with the disease for much longer. [1] With suppressive antiviral therapy, some patients who have Mollaret's report experiencing fewer attacks. However, there are some that have flare ups all throughout the year. [1]
Transverse myelitis (TM) is a rare neurological condition wherein the spinal cord is inflamed. The adjective transverse implies that the spinal inflammation (myelitis) extends horizontally throughout the cross section of the spinal cord; the terms partial transverse myelitis and partial myelitis are sometimes used to specify inflammation that affects only part of the width of the spinal cord. TM is characterized by weakness and numbness of the limbs, deficits in sensation and motor skills, dysfunctional urethral and anal sphincter activities, and dysfunction of the autonomic nervous system that can lead to episodes of high blood pressure. Signs and symptoms vary according to the affected level of the spinal cord. The underlying cause of TM is unknown. The spinal cord inflammation seen in TM has been associated with various infections, immune system disorders, or damage to nerve fibers, by loss of myelin. As opposed to leukomyelitis which affects only the white matter, it affects the entire cross-section of the spinal cord. Decreased electrical conductivity in the nervous system can result.
Viral meningitis, also known as aseptic meningitis, is a type of meningitis due to a viral infection. It results in inflammation of the meninges. Symptoms commonly include headache, fever, sensitivity to light and neck stiffness.
Varicella zoster virus (VZV), also known as human herpesvirus 3 or Human alphaherpesvirus 3 (taxonomically), is one of nine known herpes viruses that can infect humans. It causes chickenpox (varicella) commonly affecting children and young adults, and shingles in adults but rarely in children. VZV infections are species-specific to humans. The virus can survive in external environments for a few hours.
Lumbar puncture (LP), also known as a spinal tap, is a medical procedure in which a needle is inserted into the spinal canal, most commonly to collect cerebrospinal fluid (CSF) for diagnostic testing. The main reason for a lumbar puncture is to help diagnose diseases of the central nervous system, including the brain and spine. Examples of these conditions include meningitis and subarachnoid hemorrhage. It may also be used therapeutically in some conditions. Increased intracranial pressure is a contraindication, due to risk of brain matter being compressed and pushed toward the spine. Sometimes, lumbar puncture cannot be performed safely. It is regarded as a safe procedure, but post-dural-puncture headache is a common side effect if a small atraumatic needle is not used.
Shingles, also known as herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area. Typically the rash occurs in a single, wide mark either on the left or right side of the body or face. Two to four days before the rash occurs there may be tingling or local pain in the area. Other common symptoms are fever, headache, and tiredness. The rash usually heals within two to four weeks; however, some people develop ongoing nerve pain which can last for months or years, a condition called postherpetic neuralgia (PHN). In those with poor immune function the rash may occur widely. If the rash involves the eye, vision loss may occur.
Keratitis is a condition in which the eye's cornea, the clear dome on the front surface of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves any of the following symptoms: pain, impaired eyesight, photophobia, red eye and a 'gritty' sensation. Diagnosis of infectious keratitis is usually made clinically based on the signs and symptoms as well as eye examination, but corneal scrapings may be obtained and evaluated using microbiological culture or other testing to identify the causative pathogen.
Aciclovir (ACV), also known as acyclovir, is an antiviral medication. It is primarily used for the treatment of herpes simplex virus infections, chickenpox, and shingles. Other uses include prevention of cytomegalovirus infections following transplant and severe complications of Epstein–Barr virus infection. It can be taken by mouth, applied as a cream, or injected.
Valaciclovir, also spelled valacyclovir, is an antiviral medication used to treat outbreaks of herpes simplex or herpes zoster (shingles). It is also used to prevent cytomegalovirus following a kidney transplant in high risk cases. It is taken by mouth.
Aseptic meningitis is the inflammation of the meninges, a membrane covering the brain and spinal cord, in patients whose cerebral spinal fluid test result is negative with routine bacterial cultures. Aseptic meningitis is caused by viruses, mycobacteria, spirochetes, fungi, medications, and cancer malignancies. The testing for both meningitis and aseptic meningitis is mostly the same. A cerebrospinal fluid sample is taken by lumbar puncture and is tested for leukocyte levels to determine if there is an infection and goes on to further testing to see what the actual cause is. The symptoms are the same for both meningitis and aseptic meningitis but the severity of the symptoms and the treatment can depend on the certain cause.
Viral encephalitis is inflammation of the brain parenchyma, called encephalitis, by a virus. The different forms of viral encephalitis are called viral encephalitides. It is the most common type of encephalitis and often occurs with viral meningitis. Encephalitic viruses first cause infection and replicate outside of the central nervous system (CNS), most reaching the CNS through the circulatory system and a minority from nerve endings toward the CNS. Once in the brain, the virus and the host's inflammatory response disrupt neural function, leading to illness and complications, many of which frequently are neurological in nature, such as impaired motor skills and altered behavior.
Gingivostomatitis is a combination of gingivitis and stomatitis, or an inflammation of the oral mucosa and gingiva. Herpetic gingivostomatitis is often the initial presentation during the first ("primary") herpes simplex infection. It is of greater severity than herpes labialis which is often the subsequent presentations. Primary herpetic gingivostomatitis is the most common viral infection of the mouth.
Meningoencephalitis, also known as herpes meningoencephalitis, is a medical condition that simultaneously resembles both meningitis, which is an infection or inflammation of the meninges, and encephalitis, which is an infection or inflammation of the brain tissue.
Herpes gladiatorum is one of the most infectious of herpes-caused diseases, and is transmissible by skin-to-skin contact. The disease was first described in the 1960s in the New England Journal of Medicine. It is caused by contagious infection with human herpes simplex virus type 1 (HSV-1), which more commonly causes oral herpes. Another strain, HSV-2 usually causes genital herpes, although the strains are very similar and either can cause herpes in any location.
The central nervous system (CNS) controls most of the functions of the body and mind. It comprises the brain, spinal cord and the nerve fibers that branch off to all parts of the body. The CNS viral diseases are caused by viruses that attack the CNS. Existing and emerging viral CNS infections are major sources of human morbidity and mortality.
Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, intense headache, vomiting and neck stiffness and occasionally photophobia.
Herpesviral meningitis is meningitis associated with herpes simplex virus (HSV).
Herpes simplex encephalitis (HSE), or simply herpes encephalitis, is encephalitis due to herpes simplex virus. It is estimated to affect at least 1 in 500,000 individuals per year, and some studies suggest an incidence rate of 5.9 cases per 100,000 live births.
Neurovirology is an interdisciplinary field which represents a melding of clinical neuroscience, virology, immunology, and molecular biology. The main focus of the field is to study viruses capable of infecting the nervous system. In addition to this, the field studies the use of viruses to trace neuroanatomical pathways, for gene therapy, and to eliminate detrimental populations of neural cells.
Lymphocytic pleocytosis is an abnormal increase in the amount of lymphocytes in the cerebrospinal fluid (CSF). It is usually considered to be a sign of infection or inflammation within the nervous system, and is encountered in a number of neurological diseases, such as pseudomigraine, Susac's syndrome, and encephalitis. While lymphocytes make up roughly a quarter of all white blood cells (WBC) in the body, they are generally rare in the CSF. Under normal conditions, there are usually less than 5 white blood cells per µL of CSF. In a pleocytic setting, the number of lymphocytes can jump to more than 1,000 cells per µL. Increases in lymphocyte count are often accompanied by an increase in cerebrospinal protein concentrations in addition to pleocytosis of other types of white blood cells.
Chronic meningitis is a long-lasting inflammation of the membranes lining the brain and spinal cord. By definition, the duration of signs, symptoms and inflammation in chronic meningitis last longer than 4 weeks. Infectious causes are a leading cause and the infectious organisms responsible for chronic meningitis are different than the organisms that cause acute infectious meningitis. Tuberculosis and the fungi cryptococcus are leading causes worldwide. Chronic meningitis due to infectious causes are more common in those who are immunosuppressed, including those with HIV infection or in children who are malnourished. Chronic meningitis sometimes has a more indolent course than acute meningitis with symptoms developing more insidiously and slowly. Also, some of the infectious agents that cause chronic infectious meningitis such as mycobacterium tuberculosis, many fungal species and viruses are difficult to isolate from the cerebrospinal fluid making diagnosis challenging. No cause is identified during initial evaluation in one third of cases. Magnetic resonance imaging (MRI) of the brain is more sensitive than computed tomography and may show radiological signs that suggest chronic meningitis, however no radiological signs are considered pathognomonic or characteristic. MRI is also normal in many cases further limiting its diagnostic utility.