Prognosis
If the treatment is initiated quickly, about 80% of patients now survive, more than half of whom have no permanent damage. The most common neurological deficit is memory impairment. After herpes encephalitis, there is also an increased risk of permanent seizures (post-encephalitic epilepsy), which develop in the exact region of the brain where the inflammation was previously located: in the lateral (=temporal) lobe of the brain.
They require an anticonvulsive (=preventing epileptic seizures) long-term therapy. The various stages of herpes encephalitis occur very quickly. Within a few days, serious complications with serious late effects can occur.
For this reason, an early start of therapy is necessary. If antiviral treatment is started early, the probability of survival is approximately 80%. In the advanced stage of herpes encephalitis, the patient may experience dizziness, impaired perception (impaired vision, impaired sense of smell), paralysis and painful neck stiffness.
Due to the swelling of the brain tissue in the course of the inflammation, there is a risk that vital centers of the brain stem may be trapped in the bony skull. A rapid death is therefore also possible due to a constriction of the respiratory center. In some cases, permanent symptoms may occur despite successful treatment of herpes encephalitis.
In the case of so-called post-encephalitic epilepsy, the patient frequently has epileptic seizures. Drug therapy for epilepsy may be necessary. In addition, the patient may suffer from memory disorders or memory loss. These depend on the region of the brain affected by the inflammation (encephalitis).
Herpes simplex encephalitis in babies
Infection with herpes viruses occurs in babies in two ways. One possibility is infection during the birth process when the mother has genital herpes. Infection is also possible in the first months of life by parents and other caregivers who have lip herpes.
As the immune system of babies is not yet fully developed, they are particularly at risk, as viruses can spread almost unhindered in the body. In simple cases, only the skin, mucous membrane and conjunctivitis are affected. In severe cases, the central nervous system is affected, leading to herpes simplex encephalitis.
This first manifests itself in flu-like symptoms with a weakness in the baby’s drinking. This leads to high fever and seizures. The viruses lead to the destruction of important structures in the brain.It can lead to consequences such as permanent neurological damage, developmental disorders and intelligence deficits.
Despite treatment, fatal outcomes occur in 50-80% of cases. The therapy of Herpes simplex encephalitis consists, as in adults, of an antiviral therapy with Aciclovir intravenously for 14 days. In addition, fever should be reduced, in the case of seizures an anticonvulsant therapy and, if necessary, a therapy of the cerebral pressure should be performed.