What is meningitis?
Meningitis is an infection of the meninges, the membranes surrounding the brain. Below you can find information on bacterial, viral, and chronic meningitis.
Bacterial Meningitis
Bacterial meningitis is a life-threatening condition. Despite effective antibiotics and swift treatment, 25% of patients do not survive the infection.
Those who do survive often suffer from complications such as hearing impairment, paralysis, or concentration and memory deficits. Fortunately, the incidence of bacterial meningitis in children has significantly decreased over the past 20 years due to the introduction of vaccination. Nowadays, the most common bacteria causing the infection are pneumococcus (Streptococcus pneumoniae) and meningococcus (Neisseria meningitidis). Meningococcus mainly affects children and young adults (ages 15-25), while pneumococcus primarily affects infants and the elderly. Bacteria can invade the meninges through, for instance, an ear or sinus infection. Initial symptoms may resemble the flu, followed by characteristic signs such as severe headache, neck stiffness, and drowsiness. The disease progresses rapidly, so early recognition is crucial. A lumbar puncture is necessary to diagnose meningitis, which detects the bacteria in the cerebrospinal fluid. Sometimes a CT scan of the head is required before the lumbar puncture to rule out other conditions, such as a brain abscess. Bacterial meningitis is treated with antibiotics and anti-inflammatory drugs (dexamethasone). After starting treatment, complications can still arise. Patients may develop hearing loss (20-25%) or epilepsy (25%), suffer a stroke (20-25%), or develop hydrocephalus (buildup of fluid in cavities within the brain, 5%). Because of these complications, further tests like a head scan (CT or MRI), an EEG, or additional lumbar punctures may be required. Antibiotic treatment lasts between 1 and 3 weeks, depending on the bacteria. Patients may also need to be examined by other specialists such as a cardiologist, to check for endocarditis, or an ENT specialist for ear surgery or a hearing implant.
Viral Meningitis/ Encephalitis
Viruses can cause meningitis and encephalitis (inflammation of the brain). Viral meningitis is generally less severe than bacterial meningitis or viral encephalitis. The illness resembles the flu and usually resolves after a few days. Treatment is often unnecessary, except for painkillers to relieve headaches. However, viral encephalitis is a severe condition, and patients may present with symptoms like seizures, fever, behavioral changes, or even coma. A lumbar puncture can diagnose the disease by detecting the virus in the cerebrospinal fluid, though a brain scan is frequently performed too. Treatment involves antiviral medications, administered intravenously (aciclovir). Unfortunately, mortality is high and survivors may suffer from cognitive deficits.
Chronic Meningitis
Chronic meningitis is an inflammation of the meninges lasting one month or more. The cause can be a slowly progressive infection, such as tuberculosis, HIV, or syphilis. Diseases transmitted by animals, ticks, or insects (e.g., Cat-scratch disease, Lyme disease, or West Nile virus) or tropical infections brought from abroad are also considered. Non-infectious causes can also lead to chronic meningitis, including medication use, cancers, and inflammatory diseases like sarcoidosis. Patients with chronic meningitis can experience various symptoms, including fever, headache, nausea, memory deficits, or confusion. These symptoms develop gradually and can vary in severity. Diagnosing chronic meningitis requires extensive testing, including blood tests, multiple lumbar punctures, and brain or body scans. A definitive diagnosis is not always possible and a treatment may sometimes be started as a trial without a clear understanding of the underlying condition. In those cases, response to treatment is an important clue in identifying the disease. Due to the difficulty of diagnosing chronic meningitis, patients are frequently referred to Amsterdam UMC for a second opinion.
What is neurosarcoidosis?
Sarcoidosis is a disorder of the immune system that causes damage to the body. It is an uncontrolled immune response to a sometimes unknown trigger in susceptible patients. In sarcoidosis, clusters of inflammatory cells (or granulomas), appear throughout the body. These granulomas are commonly found in the lungs, but the skin and eyes can be affected too. About 1 in 20 patients develop neurosarcoidosis, a condition in which the nervous system is involved. Neurosarcoidosis might cause symptoms such as facial paralysis, meningitis, or epilepsy, but symptoms and severity vary significantly from person to person. When the granulomas affect the spinal cord, patients might develop paralysis in the legs. Small nerve branches in the feet might sometimes be affected, resulting in altered sensation and pain.
Diagnosing neurosarcoidosis can be challenging. Granulomas must be observed in nerve or brain tissue for a definitive diagnosis. However, these procedures are often too invasive, hence the diagnosis is usually made by detecting granulomas in another part of the body, commonly in the lymph nodes or lungs. The combination of neurological symptoms and radiologic or cerebrospinal fluid abnormalities, together with sarcoidosis in other parts of the body, results in the diagnosis of probable neurosarcoidosis. This process often involves blood tests, a lumbar puncture, nerve conduction studies, and scans of the nervous system and other parts of the body.
If neurosarcoidosis is likely, treatment may be necessary. Treatment involves medications to suppress the immune system, such as prednisone. This fast-acting hormone can be given either intravenously or as tablets in a short course. A combination of both is often needed to quickly and effectively treat the disease. If the disease cannot be controlled with prednisone or if long-term treatment is necessary, a second immunosuppressant such as methotrexate or azathioprine, may be given. These medications are also used for other immune system disorders like rheumatoid arthritis. Sometimes, doctors may opt for a treatment with specific, powerful antibodies such as infliximab.
One in three people do not fully recover despite treatment. Currently, we are conducting several scientific research projects to improve the diagnosis and treatment of neurosarcoidosis. In doing so, we work closely with Erasmus MC in Rotterdam, where lots of research on sarcoidosis is done too. For more information, please refer to the section ‘Research’.
What is neuroborreliosis (Lyme disease)?
Lyme disease is an infection with the bacteria Borrelia burgdorferi and is transmitted by ticks. Not all ticks carry this bacteria (about 10 to 30% of ticks in the Netherlands), and not everyone infected with the bacteria develops symptoms. The first symptom is often a characteristic red ring at the site of infection that gradually expands (erythema migrans). However, this red ring may also be absent. The bacteria spread throughout the body and cause infections in various areas. The skin and joints are often affected, but the nervous system can be affected too. When the bacteria infect the nervous system, it is called neuroborreliosis. Neuroborreliosis can present in different ways, for instance with facial paralysis, meningitis, or pain and weakness in the arms or legs caused by nerve root inflammation.
The diagnosis of neuroborreliosis can be confirmed if antibodies against the bacteria are detected in both the blood and cerebrospinal fluid. These antibodies may be absent in the first few weeks after the infection, but if symptoms persist, Lyme disease can be reliably diagnosed with these tests. If Borrelia antibodies are found in the blood and there are neurological symptoms, a lumbar puncture will be performed to investigate neuroborreliosis.
The treatment for neuroborreliosis involves administering antibiotics intravenously. For more information about the diagnosis and treatment of Lyme disease at the Amsterdam UMC, please refer to the brochures from the Amsterdam UMC Multidisciplinary Lyme Disease Center:
What is spontaneous intracranial hypotension?
The meninges form a sac of sorts around the brain and spinal cord. This sac is filled with cerebrospinal fluid, which allows the brain to 'float' within the skull and provides shock absorption. Spontaneous intracranial hypotension occurs when cerebrospinal fluid leaks from this membrane through, for example, a tear. Intracranial is the medical term for being within the skull, and hypotension is the medical term for a low pressure.
Symptoms
The symptoms and severity of these symptoms can vary amongst patients with spontaneous intracranial hypotension. Many patients experience positional headaches, which worsen when standing up and improve when lying down. This can have a very disabling effect on daily life. Other commen symptoms include tinnitus, a feeling of fullness in the ears, dizziness, nausea, vomiting, and inability to tolerate light and/or sound. For some patients, symptoms may change over time.
How does spontaneous intracranial hypotension develop?
A tear in the meninges can be caused by, for example, a bony spur from a vertebra or weak connective tissue due to genetic disorders. In other patients, a faulty connection may develop between the cerebrospinal fluid and a blood vessel, causing the cerebrospinal fluid to leak away through the vessel. The medical term for this is 'CSF-venous fistula'. Such causes are called 'spontaneous', as compared to 'traumatic' causes, such as after back surgery, a spinal tap, or a (traffic) accident.
When the cerebrospinal fluid pressure is too low, the brain cannot 'float' sufficiently. The brain sags downward, stretching the meninges. This may cause a headache when standing up. When lying down, the cerebrospinal fluid pressure restores, and the headache subsides.
Diagnosis and treatment
Your doctor will make a diagnosis based on your symptoms, your history, and possibly a spinal tap and or imaging. Sometimes advanced imaging is required, where contrast is injected into the cerebrospinal fluid with a spinal tap.
Treatment is aimed at stopping the leak. The treatment you receive depends on the type of leak. The first step is often a blood patch. This is small injection of one's own blood, administered via a spinal tap towards the leak. This can help the tear heal. Sometimes, multiple blood patches are necessary. For some patients, a procedure from interventional radiology or neurosurgery experts is required.
At Amsterdam UMC, neurology, (neuro)interventional radiology, neurosurgery, and anesthesiology are involved in providing this specialised care. This centre also conducts scientific research into spontaneous intracranial hypotension. More information can be found here.
What is a lumbar puncture (spinal tap)?
A lumbar puncture (or spinal tap) is necessary for diagnosing neurological infections and inflammatory diseases, as it allows for cerebrospinal fluid examination. Cerebrospinal fluid is produced in the brain's ventricles and circulates around the central nervous system (the brain and spinal cord). This fluid contains various substances and cells, such as white blood cells, that protect the brain from infections.
During a lumbar puncture, a needle is inserted between the vertebrae into the spinal canal, where cerebrospinal fluid is present around the nerve roots. These nerves cannot be damaged during the procedure; they are simply pushed aside by the needle (similar to how a fork moves spaghetti).
A lumbar puncture can be risky if you are taking anticoagulants — especially those requiring monitoring by a thrombosis service (acenocoumarol, sintrom, or marcoumar). Always inform your doctor if you are on these medications before scheduling a lumbar puncture. It may be necessary to stop your medication temporarily.
A potential complication of a lumbar puncture is cerebrospinal fluid leakage, which can lead to reduced pressure in the head. This results in headaches that improve when lying down. This complication occurs in about 2-5% of patients and often resolves spontaneously within 24 hours. If the symptoms persist for 3 days or more, contact the doctor who performed the procedure.
Neurologists and neurology residents perform lumbar punctures weekly and are highly skilled in this procedure. However, it is possible that the procedure may not be successful on the first attempt. The doctor performing the lumbar puncture will explain the procedure and risks beforehand.
Amsterdam UMC Patient Information Leaflet on Lumbar Puncture
What research is being conducted on neurological infections and inflammatory diseases?
At the Department of Neurology at the Amsterdam UMC, research on neurological infections and inflammatory diseases has been ongoing for years. By collecting patient data, biological samples, and conducting laboratory experiments, we aim to better understand these diseases and develop new diagnostic and treatment strategies.
How can I contribute to the research?
Our research aims to improve the prevention, diagnosis, treatment, and follow-up of patients with neurological infections and inflammatory diseases. We are committed to disseminating guidelines for diagnosis and treatment to ensure that everyone receives the best possible care. With the help of donations, we can continue our scientific research and initiate new research projects. Your contribution to our research is greatly appreciated.
How can I get in touch?
The Department of Neurology at Amsterdam UMC focuses on neurological infections and inflammatory diseases in patient care and research. This means that there is a specialized outpatient clinic for this patient population.