Meningitis is an infection that inflames the meninges. Meningitis can be caused by bacteria, viruses and other pathogens; in some cases, it can also be caused by other illnesses and diseases. In adults, the main symptoms usually include headaches, fever and neck stiffness. Various other symptoms can also develop depending on the form of meningitis. If the infection is left untreated, dangerous complications may arise. In this article, we have collated key information on meningitis, from causes and symptoms to details about diagnosis and treatment.
What is meningitis?
Meningitis is inflammation of the meninges – layers of connective tissue that surround the brain and spinal cord (cerebral and spinal membranes). Different pathogens can cause these tissues to become inflamed, which is the condition known as meningitis. It should not be confused with encephalitis, which is an inflammation of the brain itself. If both inflammations occur simultaneously, this is known as meningoencephalitis.
Meningitis – causes and forms
A distinction is made between different forms of meningitis depending on the underlying cause. Bacterial meningitis is, as the name suggests, a form of meningitis caused by bacteria. Causes of bacterial meningitis include pneumococci, meningococci (meningococcal meningitis), staphylococci, listeria and Haemophilus influenzae. Meningococcal meningitis is particularly dangerous.
The mode of infection depends on the pathogen in question. A common mode of infection is droplet infection, in which the virus is transmitted through tiny respiratory droplets that are produced when an infected person speaks, coughs or sneezes and are ingested by others who breathe in that air. However, bacterial meningitis can also develop in the course of another infectious disease such as tuberculosis or syphilis. In addition to bacteria, viruses and fungi can also cause meningitis (abacterial meningitis). Potential causes of viral meningitis include: Coxsackieviruses A and B; herpes simplex virus types 1 and 2; the early summer meningoencephalitis virus; the varicella zoster virus; the mumps virus, and the measles virus. The mode of infection depends on the pathogen involved. Coxsackieviruses, for instance, are transmitted via droplet infection; however, the most well-known form of viral meningoencephalitis, early summer meningoencephalitis, is mostly transmitted by tick bites. Furthermore, meningitis can also develop as a result of certain other illnesses and diseases including cancers, sarcoidosis and systemic lupus erythematosus. In such cases, meningitis is not contagious.
To begin with, meningitis usually manifests itself in the form of flu-like symptoms including a general feeling of being unwell, fatigue and lethargy, fever, headaches and joint pains. Other symptoms include painful neck stiffness, to the extent that it can be extremely painful and even almost impossible for patients to move their heads in certain ways. Other possible symptoms include increased sensitivity to light, increased sensitivity to noise, back pain, nausea and vomiting. As the infection worsens, impaired consciousness, neurological deficits, convulsions and epileptic seizures are possible – culminating in a state of deep unconsciousness.
Exactly when the first symptoms will appear, what symptoms will develop, the severity of the symptoms and the progression of the infection vary in each case and depend on factors such as the cause of the infection and the pathogen involved.
Bacterial meningitis in particular is characterised by severe symptoms that can worsen significantly in a short period of time. There are essentially three stages in the progression of bacterial meningitis: bacteria invading the brain, bacterial toxins damaging the brain cells, and the subsequent inflammatory response. Bacterial meningitis is an emergency that requires immediate medical attention.
Another particularly serious form is meningococcal meningitis, the symptoms of which can include bleeding that appears as a skin rash resembling small pinpricks. These marks, known as petechiae, can be a sign of sepsis (blood poisoning) – a potential complication of meningococcal meningitis in which bacteria spread throughout the blood stream, which requires immediate treatment. This is known as meningococcal septicaemia and can result in Waterhouse-Friderichsen syndrome, a condition leading to shock and coma.
This list of symptoms is intended as an overview and is not exhaustive; in addition, any given symptom might also be a sign of another illness. By the same token, not every symptom listed here appears in every case of meningitis. If in doubt, or if you suspect that you or someone you know might have meningitis, you should always seek medical advice – especially in the case of symptoms such as fever, headaches and neck stiffness. Meningitis is an emergency situation, so if you have even the slightest suspicion, you should consult a doctor immediately.
Infants and children may present with non-specific symptoms. Potential early indications include fever, extreme tiredness, listlessness, loss of appetite, stomach pains and, at a later stage, seizures. The painful neck stiffness, which is often a typical symptom of meningitis in adults, is not always present in infants and small children. In fact, the symptoms experienced by children may be somewhat less pronounced at first, which can complicate diagnosis in the early stages of infection. However, symptoms can also develop quickly in small children and lead to complications, which is why it is always important to consult a doctor immediately if you have even a slight suspicion that a small child may have meningitis.
suspect the patient has meningitis. This involves taking cerebrospinal fluid from the spinal canal to examine for signs of infection and pathogens. A lumbar puncture may be contraindicated in some circumstances. A blood test may also be conducted. Furthermore, imaging techniques such as computerised tomography (CT) and magnetic resonance tomography (MRT) scans may be used alongside other tests. The diagnostic steps used may differ from patient to patient and also depend on the circumstances (such as the age of the patient, their symptoms and the severity of their symptoms).
The treatment of meningitis depends on the cause. It is important for treatment to be administered in hospital as the course of the infection can be difficult to predict, particularly in the early stages. Patients with bacterial meningitis in particularly require very careful observation. Bacterial meningitis is treated with antibiotics. It is important to administer antibiotics as early as possible as the prognosis can otherwise worsen dramatically. People who have been in contact with the patient may also be given antibiotics as a preventive measure.
Viral meningitis is treated with antiviral therapies. Again, being able to diagnose the condition and begin treatment with specific antiviral and supplementary therapies as quickly as possible has a significant influence on the course of the infection and the scale of subsequent complications. However, specific medication has not yet been developed to combat every virus. Analgesic and antipyretic medications combined with bed rest can help to soothe the symptoms.
Meningitis is, in essence, a dangerous and even life-threatening illness. The prognosis depends firstly on the cause, but also on how fast an appropriate course of treatment can be started, the age and general health of the patient and other factors (for instance, meningitis is usually more severe in children and older patients as their immune systems are not as strong as those of adults). Without treatment, bacterial meningitis is often fatal. In the absence of complicating factors, and provided that specialist treatment is started promptly, the prospects of recovery are generally good. One potential method of preventing meningitis is being vaccinated against certain pathogens.
Meningitis: Inflammation of the meninges
Cause: Bacteria, viruses, fungi and other pathogens (rare), certain other illnesses
Symptoms: Fever, headache, neck stiffness
Infants/children often present with non-specific or less pronounced symptoms at first
Diagnosis: Anamnesis, physical examination, lumbar puncture, imaging scans, blood tests (depending on individual circumstances)
Therapy: Depends on cause. Bacterial meningitis: antibiotics. Viral meningitis: antiviral medication (if available), symptomatic treatment
Preventive measures: Vaccination against certain pathogens (see current vaccination schedule for Austria)
Important: Meningitis is an emergency situation. If you have even the slightest suspicion, consult a doctor immediately.
Weber J.; Aktuelle intensivmedizinische Aspekte der bakteriellen Meningitis, Neuro 01/2019, MedMedia Verlag and Mediaservice GmbH
Koch E. M.; Neue Impfstoffe gegen Meningokokkeninfektionen - Immer breiter aufgestellt gegen bakterielle Meningitis, CongressSelection 11/2015, Rosenfluh Publikationen AG
Weber J. R.; Ambulant erworbene bakterielle Meningitis - Diagnose und neurologische Intensivtherapie, Neuro 04/2013, MedMedia Verlag and Mediaservice GmbH
Schmutzhard E.; Bakterielle Meningitis und virale Enzephalitis, Klinik 05/2012, MedMedia Verlag and Mediaservice GmbH
Pfister H.-W. et al.; S2k-Leitlinie, Ambulant erworbene bakterielle (eitrige) Meningoenzephalitis im Erwachsenenalter, 08/08/2018, URL: https://www.dgn.org/leitlinien/3230-030-089-ambulant-erworbene-bakterielle-eitrige-meningoenzephalitis-im-erwachsenenalter-2015
Meningokokken-Erkrankungen – RKI Ratgeber, Robert Koch Institute, 01/11/2018, URL: https://www.rki.de/DE/Content/Infekt/EpidBull/Merkblaetter/Ratgeber_Meningokokken.html
Autor: Katharina Miedzinska, MSc