Definition
Meningitis is an inflammation of the meninges surrounding the brain caused by bacteria or viruses with sometimes life-threatening consequences.
Causes
There are numerous pathogens, such as viruses or bacteria, which can enter the body and either remain unnoticed for a certain time or can lead directly to an infection of the meninges. These include E. coli, streptococci, listeria, meningococcus, Haemophilus influenzae, pneumococcus or Neisseria. Furthermore, there are still numerous hospital germs with which patients can become infected on wards.
These include Pseudomonas aeruginosa, staphylococci and enterobacteria. Patients who are already immunocompromised due to medication or a previous illness also have an increased risk of developing meningitis due to listeria or cryptococci. Besides bacteria, numerous viruses can also lead to meningitis. Coxsackie, echo or mumps viruses, but also measles, cytomegalovirus and the TBE virus are among the most common pathogens. In rare cases, “Morbus Still“, a rheumatic disease, can also be the cause.
What are the first signs of meningitis?
As signs of meningitis, the occurrence of the classic three symptoms fever, headache and neck stiffness is considered. Accompanying nausea or vomiting can be interpreted as a sign of increased intracranial pressure in the context of meningitis, and represents a medical emergency. While fever and headache also occur in many other infectious diseases, neck stiffness is typical of the presence of meningitis.
Movement of the head is severely restricted and occurs in pain. To determine neck stiffness, the attending physician uses several examination methods. The patient reacts reflexively to head movement by tightening the knees (Brudzinski sign). Alternatively, bending the legs when the knees are stretched leads to bending of the knee joint (Kernig’s sign). These reflex-like movements of the patient are due to the additional tension in the area of the meninges, which surround not only the brain but also the spinal cord in the spinal column.
Symptoms
Most of the time, patients in a poor general condition go to a doctor. The most common symptom of meningitis is headache. Sensitivity to light is also regularly described.
Nausea and vomiting as well as high fever can occur, but do not have to. Other neurological complaints, such as dizziness, double vision, movement disorders or numbness, occur less frequently and usually only when the clinical picture is very advanced. Very often, neck stiffness is reported, i.e. the head cannot be bent forward passively or only with severe pain.
These symptoms occur in attenuated form in meningitis. and meningitisSigns and fever, dizziness and headachesOne of the classic symptoms of meningitis is fever. Elevated body temperature is a defensive reaction of the body to combat invading bacteria and viruses.
The level of fever varies depending on the pathogen and the patient. While a mild fever is more likely to occur in the case of a virus infection, bacterial infections can lead to very high fever within a short period of time. In infants and toddlers, meningitis can occur even without a fever.
Instead, these children are mainly characterized by a poor general condition. The most common symptom of meningitis is headache. Due to the sensitive supply of nerve fibers to the meninges, an inflammation in the area of the meninges causes irritation of the nerve fibers and severe, localized headaches.
These often occur in the back of the head and are accompanied by painful neck stiffness. Another classic symptom of meningitis is neck stiffness. Compared to the other symptoms mentioned, which also occur in many other diseases, neck stiffness is typical of meningitis.
The patient can only move the head to a limited extent or in pain. Especially the movement of the head in the direction of the sternum causes severe pain, as this movement causes additional tension in the meninges.An examination in which the physician passively lifts the head of the lying patient towards the sternum leads reflexively to the patient’s knees being tightened to reduce the pain, this phenomenon is called Brudzinski’s sign. Often the classic three symptoms of meningitis are accompanied by nausea and vomiting.
The increased intracranial pressure caused by the inflammation can irritate various centers, including the vomiting center in the area of the brain stem. This leads to nausea with sometimes severe vomiting. This is a clinical emergency, as the increased intracranial pressure can irritate and pinch other centers in the brain. With the help of imaging, in this case a computed tomography (CT) of the head, an increased intracranial pressure can be quickly ruled out.
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