Blood, urine, as well as other body fluids can help detect and identify brain and/or spinal cord infection especially when CSF analysis is not possible, or it is negative. These tests can also exclude other causes of encephalitis' mimics.
Tests for encephalitis can include: Neuroimaging, such as a brain MRI or CT scan. A lumbar puncture (spinal tap) to check for signs of infection in the brain or spinal cord. Electroencephalogram (EEG) to look for seizures or specific patterns of electrical activity in the brain.
Serologic Tests
Some causes of encephalitis can be diagnosed by detecting serum IgM antibodies (varicella and arboviruses). Currently, IgM and immunoglobulin G (IgG) capture enzyme linked immunosorbent assays (ELISAs) are the most useful and most widely used tests for the diagnosis of arboviral encephalitis.
Your health care provider will start with a thorough physical examination and medical history. Your provider might then recommend: Brain imaging. MRI or CT images can reveal any swelling of the brain or another condition that might be causing your symptoms, such as a tumor.
Any other disease process affecting the brain may have similar signs. The most common diseases to rule out are congenital malformation and tumor. Other diseases which may be considered include metabolic diseases, neurodegenerative diseases and stroke.
Signs and Symptoms
People with severe encephalitis usually have some change in consciousness, ranging from mild confusion to coma. They will often be disoriented and delusional with possible hallucinations, agitation, and personality changes. Up to 50% of people with encephalitis may have seizures.
Up to 60 percent of cases of encephalitis remain undiagnosed. Several thousand cases are reported each year, but many more may occur since the symptoms may be mild to non-existent in most individuals.
Encephalitis is most often due to a virus, such as: herpes simplex viruses, which cause cold sores (this is the most common cause of encephalitis) the varicella zoster virus, which causes chickenpox and shingles.
Left untreated, autoimmune encephalitis can quickly become serious. It may lead to coma or permanent brain injury. In rare cases, it can be fatal.
Autoimmune encephalitis is a difficult clinical diagnosis due to the similarities in the clinical, imaging and laboratory findings of many forms of autoimmune and infectious encephalitis.
The clinical hallmark of acute encephalitis is the triad of fever, headache, and altered mental status.
Magnetic resonance imaging is the gold standard technique for brain imaging in encephalitis,12 and is abnormal in 90% of cases of HSV encephalitis,4 but may be normal or subtly abnormal in autoimmune encephalitis (Fig 2).
Recovering from encephalitis can be a long, slow and difficult process. Many people will never make a full recovery. Specialised services are available to aid recovery and help the person adapt to any persistent problems – this is known as rehabilitation.
Other symptoms include nausea or vomiting, double vision, drowsiness, and confusion. More severe illnesses can cause speech, hearing, or vision problems. If it's left untreated, you could develop cognitive difficulties with progressive loss of consciousness, seizures, or muscle weakness.
People who have HIV / AIDS , take immune-suppressing medicines or have another condition causing a weakened immune system are at increased risk of encephalitis.
At a later time, emotional or physical stress can reactivate the virus to cause an infection of the brain. It causes the most subacute (between acute and chronic) and chronic (lasting three or more months) encephalitis infections in humans.
On average, in the mild form, the body recovers in 1-2 months, in the moderate form in 3-4 months, and in the severe condition in several years. People who have survived the dangerous disease receive special treatment.
Diagnosis and Tests
The sooner you receive care, the better your chances of recovery. For mild encephalitis symptoms, your first step may be going to an urgent care center. For severe issues, like seizures and loss of consciousness, the best place to go for care is an emergency room.
Viruses are the most common cause of encephalitis. They can include HSV, measles, and viruses spread by mosquitoes, ticks, and other insects. Encephalitis typically begins with a fever and headache. The symptoms rapidly worsen, and there may be seizures, confusion, drowsiness, loss of consciousness, and possibly coma.
Summary. Viral encephalitis is an inflammation of the brain caused by a virus. The most serious potential complication is permanent brain damage. Children aged under one year and adults aged over 55 years are at increased risk of life-threatening complications.
Headache is the most common symptom anytime the brain begins to swell. Other symptoms include dizziness, nausea, mood changes, cognitive changes, seizure, lack of coordination, numbness, and double vision.
CT showed the characteristic pattern of herpes simplex encephalitis in all cases. This is a temporal lobe hypodense lesion (unilateral, 5 cases; bilateral, 2 cases) with a small interspersed hyperdense region. The hyperdense component represents hemorrhage. Mass effect was seen in all cases.
The CSF test for the presence of antibodies is important because it is more sensitive and reflects disease activity in many autoimmune encephalitis, although antibody tests can be negative even in the presence of autoimmune encephalitis.