Meningitis is usually caused by a virus, in which case the prognosis is good and the treatment usually symptomatic. Bacterial meningitis is less common, but its course is far more severe. Encephalitis or meningoencephalitis also involves inflammation of the brain parenchyma. The key symptoms of all these infections are headache and fever. Both of these are non-specific symptoms and need not both be present, and by no means every patient with these symptoms will have an intracranial infection. Thus, it can be difficult to diagnose infections of the central nervous system and cerebral meninges. This is certainly the case in very young and very old patients, who generally display even fewer classic symptoms. This chapter covers various infections of the central nervous system, cerebral meninges, spinal cord, and nerves. The symptomatology depends on the degree of damage to the brain parenchyma or spinal cord. There is a particular focus on meningitis (sect. 24.1), abscess (sect. 24.2), and viral diseases (sect. 24.3).
