by admin-blog-kh | May 9, 2025 1:07 pm
Encephalitis is a life-threatening condition involving brain swelling (inflammation) caused by a bacterial or viral infection, an autoimmune response (where the immune cells mistakenly attack healthy brain cells), or an unknown cause. Brain inflammation can lead to symptoms such as headaches, light sensitivity, a stiff neck, seizures, and mental confusion. The cause and severity of the inflammation, the affected area of the brain, and the timing of treatment determine the degree and type of damage, impacting patient outcomes with either minor or major impairment.
Long-term consequences may include cognitive, physical, behavioural, and emotional problems (discussed below). According to neurologists[12], several factors increase the risk of developing encephalitis, such as age, a weakened immune system, geographical region, season, and autoimmune disease[13]. Encephalitis is non-contagious (it is not transmitted from one person to another).
Viruses are the most common cause of infectious encephalitis, including human herpes viruses (such as herpes simplex virus, which causes cold sores, and varicella-zoster virus, which causes chickenpox), cytomegalovirus, Epstein-Barr virus, and viruses responsible for rashes like rubella, mumps, and measles. Other culprits include throat and chest viruses (enteroviruses and the flu), gut viruses (enteroviruses and echo virus), tick-borne encephalitis virus, and insect-borne viruses (West Nile virus and Japanese encephalitis virus).
In rare cases, bacteria (e.g., Listeria, pneumococcal, meningococcal, and Mycoplasma), fungi (e.g., Candida, Cryptococcus, and Histoplasma), and parasites (e.g., Toxoplasma and malaria parasites) can also cause encephalitis.
Autoimmune encephalitis occurs when the immune system[14] mistakenly attacks healthy brain cells. This can be triggered by a prior infection (post-infection encephalitis), a cancerous or non-cancerous tumour (paraneoplastic syndrome), or the presence of specific antibodies in the blood, such as N-methyl D-aspartate receptor (NMDAR), which causes anti-NMDA receptor encephalitis (more common in young individuals), or an unknown cause.
The symptoms of infectious encephalitis develop quickly, while those of autoimmune encephalitis progress more slowly.
Infectious encephalitis starts with flu-like symptoms, such as headache, fever, muscle/joint aches, and fatigue. Within hours or days, more severe symptoms emerge, including neck stiffness, confusion, hallucinations, seizures, muscle weakness, limited mobility of the face or certain body parts, speech/hearing problems, and loss of consciousness.
In infants and young children, additional symptoms may include:
High-risk individuals should be vigilant about symptoms and seek immediate medical attention. They should also take precautions to minimize exposure to potential causative agents in high-risk areas and maintain a healthy immune system through exercise and a nutritious diet.
A physical exam assesses nerve function, motor/sensory function, balance, coordination, mood swings, and mental status. A medical history is taken, reviewing recent activities, including exposure to ticks, insects, or animals, contact with sick individuals, travel history (to areas where encephalitis is prevalent), symptoms and their duration, and pre-existing medical conditions. Early diagnosis is critical, as symptoms can escalate rapidly to cause brain damage, loss of speech/hearing/vision, or death.
Treatment for encephalitis[18] should start immediately. For viral causes (e.g., HSV or chickenpox), anti-viral medications like acyclovir (for HSV) or ganciclovir (for CMV encephalitis) are administered intravenously. If the cause is bacterial or fungal, appropriate anti-bacterial or anti-fungal medications are given.
For autoimmune encephalitis, corticosteroids, immunoglobulin therapy, or plasmapheresis (a procedure to remove harmful substances from the blood) may be used. In some cases, long-term immunosuppressive treatment with medications like azathioprine, rituximab, or tocilizumab is required. If an underlying tumour is the cause, treatment may include radiation, chemotherapy[19], or surgery.
Supportive care in the hospital is essential, especially for severe cases, and includes mechanical ventilation, intravenous fluids, pain management[20], anti-seizure medications, and anti-inflammatory treatments.
If encephalitis leads to complications, follow-up therapy is necessary, including rehabilitation to improve memory, cognitive function, physical therapy to enhance coordination and mobility, speech therapy, and psychotherapy to manage mood disorders.
Mild cases of encephalitis can result in a full recovery, but severe cases can lead to permanent challenges, such as seizures, memory loss, blindness, and hearing loss. Despite advances in diagnosis and treatment, encephalitis remains fatal in about 10% of cases. Comprehensive rehabilitation[22], involving specialists in speech therapy, neurology[23], occupational therapy, and nutrition, is essential for improving long-term outcomes.
Encephalitis is characterized by brain inflammation, often caused by viral infections or autoimmune responses, leading to neurological, behavioural, and physical disruptions. Early diagnosis and treatment are critical to preventing severe outcomes, including brain damage or death. Although encephalitis cannot be fully prevented, vaccination can reduce the risk of certain viral causes. Prompt treatment, followed by comprehensive rehabilitation, can help patients recover and manage long-term effects.
For more information or specialized care for encephalitis, consider reaching out to the expert neurologists at Kauvery Hospital. With branches in Chennai, Hosur, Salem, Tirunelveli, and Trichy, we’re here to support your health needs with comprehensive diagnostics and personalized treatment plans. Your well-being is our priority at Kauvery Hospital.
Encephalitis is most commonly caused by viral infections such as herpes simplex virus, Japanese encephalitis virus, and enteroviruses. It can also result from autoimmune disorders, bacterial or fungal infections, or in rare cases, have no identifiable cause.
Early signs include headache, fever, fatigue, and confusion. Severe cases may involve seizures, hallucinations, loss of consciousness, and behavioural changes. Medical tests like MRI, lumbar puncture, and blood tests confirm the diagnosis.
Mild cases may resolve with full recovery, while severe cases can cause lasting complications. Early treatment improves the chances of recovery and reduces the risk of permanent damage.
Long-term effects can include memory loss, speech difficulties, fatigue, mood changes, seizures, and coordination problems. Some patients may need ongoing therapy and support.
Infants, older adults, people with weakened immune systems, and those living in mosquito- or tick-prone areas are at higher risk. Certain autoimmune conditions also increase the risk.
Encephalitis is inflammation of the brain, while meningitis is inflammation of the protective membranes around the brain and spinal cord. Both share similar symptoms but require different treatments.
Kauvery Hospital is globally known for its multidisciplinary services at all its Centers of Excellence, and for its comprehensive, Avant-Grade technology, especially in diagnostics and remedial care in heart diseases, transplantation, vascular and neurosciences medicine. Located in the heart of Trichy (Tennur, Royal Road and Alexandria Road (Cantonment), Chennai (Alwarpet & Vadapalani), Hosur, Salem, Tirunelveli and Bengaluru, the hospital also renders adult and pediatric trauma care.
Chennai Alwarpet – 044 4000 6000 • Chennai Vadapalani – 044 4000 6000 • Trichy – Cantonment – 0431 4077777 • Trichy – Heartcity – 0431 4003500 • Trichy – Tennur – 0431 4022555 • Hosur – 04344 272727 • Salem – 0427 2677777 • Tirunelveli – 0462 4006000 • Bengaluru – 080 6801 6801
Source URL: https://www.kauveryhospital.com/blog/neurology/encephalitis-explained/
Copyright ©2025 Kauvery Blog unless otherwise noted.