What is Encephalitis?
Encephalitis is an inflammation of the brain, which causes the brain to swell. This changes in a child’s nervous system can lead to various symptoms like confusion, changes in alertness, and seizures.
What causes encephalitis?
Encephalitis is primarily caused by viral infections including herpes simplex virus, measles virus, mumps, varicella-zoster, Epstein Barr virus, West Nile virus, and rabies virus. The incidence of measles and mumps encephalitis has reduced now due to the emergence of better immunization practices. It can occur after a mild upper respiratory tract or gastrointestinal infection. Few bacterial infections like tuberculosis can also cause encephalitis.
How does infection get transmitted?
The infection can spread through various routes like respiratory secretions or gastro-intestinal tract. Infected people colonizing the virus can spread it by sneezing, coughing and kissing or by faecal-oral route.
Who are at risk of encephalitis?
- Age: In general, young children are at greater risk of most types of viral encephalitis.
- Weakened immune system: People who have primary or acquired immunodeficiency, those taking immune-suppressive medicines or have any chronic medical condition which makes the immune system weak comes under high-risk category.
- Geographical regions: Mosquito-or tick-borne viruses are common in particular geographical regions.
- Vaccination: Unvaccinated or partially vaccinated children are at higher risk.
- Environmental conditions: Unhygienic environment such as a collection of dirty water, poor hand hygiene, and close proximity with infected persons also increases the risk of disease.
What are the symptoms of encephalitis?
Encephalitis usually begins with mild symptoms of viral illness. The symptoms includes:
- Headache, vomiting
- Neck stiffness
- Sleep disturbances
- Poor feeding
- Lethargy, excessive irritability
- Skin rash
- Altered sensorium
- Behavioural changes
- Loss of consciousness (coma)
If untreated, these children can later have altered sensorium, shock and refractory seizures.
Encephalitis is a medical emergency condition that requires immediate medical care.
What are the complications of meningitis if not treated early?
A good recovery rate is observed after viral encephalitis if treated early. Delay in initiation of treatment can cause acute life-threatening events and long term complications. These may include:
- Excessive fatigability
- Cognitive deficits and learning disabilities
- Remote symptomatic epilepsy
- Behavioural issues
- Speech, vision or hearing impairment
How is encephalitis diagnosed in children?
- Detailed history and Clinical examination: An idea about your child’s symptoms and health history followed by physical and neurological examination will help in formulating an appropriate diagnosis.
- Laboratory tests: A battery of blood tests including complete blood count, sepsis screen, PCR testing for organisms and blood culture provides a clue in the diagnosis of meningitis.
- Neuroimaging: MRI brain and CT scan are the most widely used radiological tests for brain imaging. MRI brain has no radiation exposure and it gives the finer details of brain abnormalities. But MRI takes a longer time to perform and thus may require anaesthesia to complete the test. CT scan uses X-rays and thus have radiation exposure. It takes less time as compared to MRI, but misses the detailed imaging findings.
- EEG (Electroencephalogram): A procedure that records the electrical activity of the brain by means of electrodes attached to the scalp. It is important to know the nature, origin, and severity of epileptiform discharges to guide the further treatment of the child. The background activity in EEG gives an idea about the sensorium.
- Spinal tap: In this procedure, a thin needle is inserted between two vertebrae in the lower back to extract a sample of cerebrospinal fluid for laboratory analysis. It is a very important investigations for the diagnosis of meningitis, for differentiating the various types of meningitis and for guiding the treatment.
- Ophthalmological examination: Eye examination is always an important part of evaluation of neurological disorders. It gives an idea about the increase in pressure in the brain and helps in guiding further management.
How is encephalitis treated in a child?
Acute management: Child should be immediately hospitalized for treatment. Acute management mainly focuses on airway, breathing and circulation. Symptomatic treatment including fluid and electrolyte correction, maintenance of blood sugar, treatment of fever, and seizure control is very important in improving the outcome. The goal of treatment is to reduce the swelling in the brain and to prevent complications. Antiviral agent is of proven benefit only in herpes simplex encephalitis.
After recovery of acute symptoms a child may need multi-disciplinary rehabilitation, including physical, occupational, or speech therapy. Once discharged, a regular follow up is advised to assess the improvement in the clinical condition of the child.
What measures can be taken to prevent the occurrence of encephalitis?
- Complete vaccination.
- Proper environment and hand hygiene practices.
- Strengthening of the immune system by healthy and proper diet.
- Early identification of at-risk children.
- Protection from mosquitoes and ticks