Synonyms in a broader sense
Meningitis, Meningitis serosa, Meningoencephalitis Medical: Menigitis serosa
General Information
General information on the topic (What is menigitis?) can be found under our topic:
- Meningitis
Definition
The term meningitis (inflammation of the meninges) describes an inflammation (-itis) of the meninges (meninges), which can be caused by very different pathogens. There are two forms of meningitis:
- The purulent meningitis (see following text)
- Non-purulent meningitis
The purulent meningitis (purulent meningitis) is caused by bacteria. It is accompanied by high fever and a severe general clinical picture and is an absolute emergency that must be treated immediately. Non-purulent meningitis (non-purulent meningitis), which is usually caused by viruses, is usually more harmless and often occurs as part of general viral infections (except for herpes simplex encephalitis, which is an acute emergency). The symptoms and course are milder and the prognosis is better.
Viral Meningitis
(= acute, lymphocytic meningitis, simple viral meningitis)By far the most frequent form of inflammatory diseases of the central nervous system (CNS), i.e. of the brain and spinal cord with its membranes and liquor spaces, is viral meningitis (acute, lymphocytic meningitis) with 10 – 20 cases per 100000 inhabitants per year. Men are slightly more frequently affected than women. It is suspected that many general viral infections are accompanied by a mild concomitant meningitis, but this is not diagnosed.
It must be distinguished from the rare but dangerous viral encephalitis, i.e. the acute inflammation of the brain itself or also of the spinal cord (myelitis, myelon = spinal cord), which in some cases can result from such a mild infection. The pathogens of viral meningitis must be divided into two groups: In Western countries, however, more and more unusual viruses are found, such as the Hantaan virus, Puumula virus, Nipah virus, West Nile virus (WNV) and Japanese encephalitis virus (JEV).
- The primarily neurotropic viruses, i.e.
viruses which primarily penetrate the CNS along nerve roots and have the tendency to settle there and sometimes remain inconspicuous for years (virus persistence, i.e. they exist there without causing symptoms), but which can also cause “normal” viral meningitis (e.g. the varicella zoster virus (chickenpox and shingles – virus) or the TBE virus) and
- Non-primarily neurotropic viruses, i.e.
all viruses that cause our colds (“flu-like infections”), preferably in spring and autumn, and in most cases reach the meninges (meninges) with the blood in the course of this process and do not survive there (e.g. coxsackie, echo, mumps, measles or adenoviruses). They are the main causative agents of simple viral meningitis. There are regional differences with varying pathogen spectrum.
Coxsackie and echovirus infections become noticeable after an incubation period of 5 to 10 days with flu symptoms such as fever, rhinitis, vomiting, sore throat and aching limbs.
Later, the symptoms of acute viral meningitis set in. They are similar to those of bacterial meningitis with headaches and neck stiffness, but they are less pronounced, more in the sense of irritation of the meninges. Often patients are conscious and have a slight fever.
When the inflammation spreads to the brain (meningoencephalitis), focal symptoms such as an epileptic seizure, speech disorders or paralysis may occur. However, the symptoms generally subside after a few days. Here, too, the meningitis symptoms do not allow the triggering viruses to be distinguished, but the pathogen can be inferred from the accompanying clinical symptoms.
Echoviruses, for example, are more likely to be associated with gastrointestinal symptoms such as diarrhea, Coxsackie viruses with tonsillitis (Coxsackie B infections can also cause severe chest pain and heart muscle inflammation) and the Epstein-Barr virus (EBV, the pathogen causing Pfeiffer’s glandular fever) with splenic and lymph node swelling.If viral meningitis is suspected, the aim is to examine the cerebrospinal fluid by means of liquor puncture, as in bacterial meningitis. In contrast to the purulent, bacterial meningitis, only a few impressive changes can be found here: The puncture has a clear to somewhat cloudy color, since the cell count is increased, but often does not exceed 1500 cells. These are also not pus-forming cells (granulocytes) as in purulent meningitis, but lymphocytes (white blood cells).
Lymphocytes are the cells of our immune system that fight viruses and therefore do not form pus. Protein, sugar and lactate – other important markers of the cerebrospinal fluid – have approximately normal values, as does procalcitonin in the blood (always below 0.5 ng/ml), which is a sensitive marker for differentiating between purulent and non-purulent meningitis (increased only in purulent meningitis). The identification of the pathogen is best done by detecting the specific antibodies in the blood using the ELISA technique (enzyme-linked immunosorbent assay).
If the detection is not successful, PCR (polymerase chain reaction) is also used. PCR directly detects the DNA, i.e. the genetic material of the viruses, and is now used as a routine procedure for the detection of some specific viruses, especially the group of herpes viruses (HSV, VZV, CMV, EBV), but also for HIV and others. A simple viral meningitis, just like the simple viral meningoencephalitis, does not require any special therapy.
Bed rest, possibly antipyretic medication (e.g. paracetamol) and painkillers as well as stimulus shielding are useful. The prognosis is good. Permanent damage is not to be expected.
Vaccination prophylaxis For some viruses that can potentially affect the brain and meninges, vaccination in childhood is the best prophylaxis. These include the measles, rubella, mumps, chickenpox (varicella) and poliomyelitis virus (the causative agent of polio). Vaccination against the causative agent of early summer meningoencephalitis, the TBE virus, is only carried out when travelling to the corresponding risk areas (especially southern Germany, but the virus is spreading further and further north), as is the case with the Japanese Encephalitis virus.
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