Acute encephalitis is a rare and a severe condition that affects children. It is characterized by an inflammation of the brain tissue and the meninges (the latter concerning meningoencephalitis). In most cases, this condition is secondary to a viral infection. The importance of neurological sequelae is the nature of the viral infection and the age of onset.
What are the clinical signs?
The onset may occur from the neonatal period until adolescence. At the beginning, general signs and symptoms of inflammation (fever) are associated with the symptoms of impaired higher functions (disorientation, speech disorders), which eventually gets worse (consciousness disorders, coma, and convulsions). Regression of this clinical picture usually occurs on a variable time basis and often results in neurological sequelae. Diagnosis is confirmed through CT-Scan, MRI, or EEG. Meningitis is often detected through an examination of the cerebrospinal fluid (CSF) extracted by lumbar puncture.
What is the cause?
In most cases, a viral infection (measles, herpes) is responsible for this condition. Most frequently, cases of encephalitis occur following measles (one case out of 1000-2000 measles cases). Encephalitis due to herpes simplex is a rarer form and may develop during the neonatal period if the mother has genital herpes. However, in 30 to 50% of cases, no cause is ever identified.
How does the disease progress?
In the acute phase, the life-threatening risk is significant, especially for infants with herpes encephalitis who are aged less than one year (mortality rate of 50%). Once it is controlled by treatment or natural progression, the inflammatory process leaves a scar, which eventually becomes the cause of sequelaes. According to the age of onset and the type of virus, clinical signs may present as motor impairments, severe intellectual deficits, speech or behavior disorders, epilepsy, multiple disabilities, etc.
What are the suggested treatments and management strategies?
The initial infectious stage of the disease requires hospitalization, sometimes prolonged resuscitation. A specific antiviral therapy, when available (herpes), can significantly reduce the mortality rates for herpes infection. The assessment of the neurological sequelae and the nature of the sequelae (whether it is a motor, intellectual, or neuropsychological), guides the subsequent management of the child. Prevention involves vaccination for measles. For herpes (no vaccine), prevention lies primarily in the management of genital infections in pregnant women
Living with encephalitis or meningoencephalitis
It could mean to provide rehabilitation to an infant with multiple disabilities or support a child with learning difficulties secondary to aphasia. All children diagnosed with encephalitis or meningoencephalitis experience their first hospitalization under difficult circumstances. Once this period over, recovery signs are monitored over several months. Subtle disorders, such as speech and language disorders, should not be overshadowed by a speedy motor recovery.