Friday

Autoimmune Encephalitis: Treatment and Expected Outcomes video

Many cases of encephalitis are caused by an autoimmune disorder which may or may not be triggered by an infection. 
Here is a short informative video from the Autoimmune Encephalitis Alliance.  It is presented by Dr. Heather Van Mater who is a pediatric Rheumatologist.

What is meningitis? What is encephalitis? 
Infections, and less commonly other causes, in the brain and spinal cord can cause dangerous inflammation. This inflammation can produce a wide range of symptoms, including fever, headache, seizures, change in behavior or confusion and, in extreme cases, can cause brain damage, stroke, or even death. Infection of the meninges, the membranes that surround the brain and spinal cord, is called meningitis. Inflammation of the brain itself is called encephalitis. Myelitis refers to inflammation of the spinal cord. When both the brain and the spinal cord are involved, the condition is called encephalomyelitis. What causes meningitis and encephalitis? Infectious causes of meningitis and encephalitis include bacteria, viruses, fungi, and parasites. Many of these affect healthy people. For others, environmental and exposure history, recent travel or immunocompromised state (such as HIV, diabetes, steroids, chemotherapy) are important elements. There are also non-infectious causes such as autoimmune causes and medications.
Encephalitis
Encephalitis can be caused by infections. However, up to 60 percent of cases remain undiagnosed, so this is an active area of research. Several thousand cases of encephalitis are reported each year, but many more may actually occur since the symptoms may be mild to non-existent in most patients.
Most diagnosed cases of encephalitis in the United States are caused by enteroviruses, herpes simplex virus types 1 and 2, rabies virus (this can occur even without a known animal bite, such as for example due to exposure to bats), or arboviruses such as West Nile virus, which are transmitted from infected animals to humans through the bite of an infected tick, mosquito, or other blood-sucking insect. Lyme disease, a bacterial infection spread by tick bite, more typically causes meningitis, and rarely encephalitis.
Herpes simplex encephalitis (HSE) is responsible for about 10 percent of all encephalitis cases, with a frequency of about 2 cases per million persons per year. More than half of untreated cases are fatal. About 30 percent of cases result from the initial infection with the herpes simplex virus; the majority of cases are caused by reactivation of an earlier infection. Most people acquire herpes simplex type 1 (the cause of cold sores or fever blisters) in childhood so it is a ubiquitous exposure.
HSE due to herpes simplex virus type 1 can affect any age group but is most often seen in persons under age 20 or over age 40. This rapidly progressing disease is the single most important cause of fatal sporadic encephalitis in the U.S. Symptoms can include headache and fever for up to 5 days, followed by personality and behavioral changes, seizures, hallucinations, and altered levels of consciousness. Brain damage in adults and in children beyond the neonatal period is usually seen in the frontal (leading to behavioral and personality changes) and temporal lobes (leading to memory and speech problems) and can be severe.
Type 2 virus (genital herpes) is most often transmitted through sexual contact. Many people do not know they are infected and may not have active genital lesions. An infected mother can transmit the disease to her child at birth, and through contact with genital secretions. In newborns, symptoms such as lethargy, irritability, tremors, seizures, and poor feeding generally develop between 4 and 11 days after delivery.
Powassan encephalitis is the only well-documented tick-borne arbovirus in the United States and Canada. Symptoms are noticed 7-10 days following the bite (most people do not notice tick bites) and may include headache, fever, nausea, confusion, partial paralysis,coma, and seizures.
Four common forms of mosquito-transmitted viral encephalitis are seen in the United States:
  • Equine encephalitis affects horses and humans. Eastern equine encephalitis also infects birds that live in freshwater swamps of the eastern U.S. seaboard and along the Gulf Coast. In humans, symptoms are seen 4-10 days following transmission and include sudden fever, general flu-like muscle pains, and headache of increasing severity, followed by coma and death in severe cases. About half of infected patients die from the disorder. Fewer than 10 human cases are seen annually in the United States. Western equine encephalitis is seen in farming areas in the western and central plains states. Symptoms begin 5-10 days following infection. Children, particularly those under 12 months of age, are affected more severely than adults and may have permanent neurologic damage. Death occurs in about 3 percent of cases. Venezuelan equine encephalitis is very rare in this country. Children are at greatest risk of developing severe complications, while adults generally develop flu-like symptoms. Epidemics in South and Central America have killed thousands of persons and left others with permanent, severe neurologic damage.
  • LaCrosse encephalitis occurs most often in the upper midwestern states (Illinois, Wisconsin, Indiana, Ohio, Minnesota, and Iowa) but also has been reported in the southeastern and mid-Atlantic regions of the country. Most cases are seen in children under age 16. Symptoms such as vomiting, headache, fever, and lethargy appear 5-10 days following infection. Severe complications include seizure, coma, and permanent neurologic damage. About 100 cases of LaCrosse encephalitis are reported each year.
  • St. Louis encephalitis is most prevalent in temperate regions of the United States but can occur throughout most of the country. The disease is generally milder in children than in adults, with elderly adults at highest risk of severe disease or death. Symptoms typically appear 7-10 days following infection and include headache and fever. In more severe cases, confusion and disorientation, tremors, convulsions (especially in the very young), and coma may occur.
  • West Nile encephalitis was first clinically diagnosed in the United States in 1999; 284 people are known to have died of the virus the following year. There were 9,862 reported cases of human West Nile disease in calendar year 2003, with a total of 560 deaths from this disorder over 5 years. The disease is usually transmitted by a bite from an infected mosquito, but can also occur after transplantation of an infected organ or transfusions of infected blood or blood products. Symptoms are flu-like and include fever, headache, and joint pain. Some patients may develop a skin rash and swollen lymph glands, while others may not show any symptoms. At highest risk are elderly adults and people with weakened immune systems.

Who is at risk for encephalitis and meningitis?

Anyone can get encephalitis or meningitis. People with weakened immune systems, including those persons with HIV or those taking immunosuppressant drugs, are at increased risk.

How are these disorders transmitted?

Some forms of bacterial meningitis and encephalitis are contagious and can be spread through contact with saliva, nasal discharge, feces, or respiratory and throat secretions (often spread through kissing, coughing, or sharing drinking glasses, eating utensils, or such personal items as toothbrushes, lipstick, or cigarettes). For example, people sharing a household, at a day care center, or in a classroom with an infected person can become infected. College students living in dormitories—in particular, college freshmen—have a higher risk of contracting meningococcal meningitis than college students overall. Children who have not been given routine vaccines are at increased risk of developing certain types of bacterial meningitis.
Because these diseases can occur suddenly and progress rapidly, anyone who is suspected of having either meningitis or encephalitis should immediately contact a doctor or go to the hospital.

What are the signs and symptoms?

Individuals with encephalitis often show mild flu-like symptoms. In more severe cases, patients may experience problems with speech or hearing, double vision, hallucinations, personality changes, loss of consciousness, loss of sensation in some parts of the body, muscle weakness, partial paralysis in the arms and legs, sudden severe dementia, seizures, and memory loss.
Important signs of meningitis or encephalitis to watch for in an infant include fever, lethargy, not waking for feeding, vomiting, body stiffness, unexplained or unusual irritability, and a full or bulging fontanel (the soft spot on the top of the head).

How are meningitis and encephalitis diagnosed?

Following a physical exam and medical history to review activities of the past several days/weeks (such as recent exposure to insects or animals, any contact with ill persons, recent travel, or preexisting medical conditions and medications list), the doctor may order various diagnostic tests to confirm the presence of infection and inflammation. Early diagnosis is vital, as symptoms can appear suddenly and escalate to brain damage, hearing and/or speech loss, blindness, or even death.
A neurological examination involves a series of tests designed to assess motor and sensory function, nerve function, hearing and speech, vision, coordination and balance, mental status, and changes in mood or behavior. Doctors may test the function of the nervous system through tests of strength and sensation, with the aid of items including a tuning fork, small light, reflex hammer, and pins.
Laboratory screening of blood, urine, and body secretions can help detect and identify brain and/or spinal cord infection and determine the presence of antibodies and foreign proteins. Such tests can also rule out metabolic conditions that have similar symptoms. For example, a throat culture may be taken to check for viral or bacterial organisms that cause meningitis or encephalitis. In this procedure, the back of the throat is wiped with a sterile cotton swab, which is then placed on a culture medium. Viruses and bacteria are then allowed to grow on the medium. Samples are usually taken in the physician’s office or in a laboratory setting and sent out for analysis to state laboratories or to the U.S. Centers for Disease Control and Prevention. Results are usually available in 2 to 3 days.
Analysis of the cerebrospinal fluid that surrounds and protects the brain and spinal cord can detect infections in the brain and/or spinal cord, acute and chronic inflammation, and other diseases. In a procedure known as a spinal tap (or lumbar puncture), a small amount of cerebrospinal fluid is removed by a special needle that is inserted into the lower back. The skin is anesthetized with a local anesthetic prior to the sampling. The fluid, which is completely clear in healthy people, is tested to detect the presence of bacteria or blood, as well as to measure glucose levels (a low glucose level can be seen in bacterial or fungal meningitis) and white blood cells (elevated white blood cell counts are also a sign of infection). The procedure is done in a hospital and takes about 45 minutes.The individual will most often be placed on antibiotics and an antiviral drug while awaiting the final microbiology results as delay in treatment can be life-threatening.
Brain imaging can reveal signs of brain inflammation, internal bleeding or hemorrhage, or other brain abnormalities. Two painless, noninvasive imaging procedures are routinely used to diagnose meningitis and encephalitis.
  • Computed tomography, also known as a CT scan, combines x-rays and computer technology to produce rapid, clear, two-dimensional images of organs, bones, and tissues. Occasionally a contrast dye is injected into the bloodstream to highlight the different tissues in the brain and to detect signs of encephalitis or inflammation of the meninges. CT scans can also detect bone and blood vessel irregularities, certain brain tumors and cysts, herniated discs, spinal stenosis (narrowing of the spinal canal), blood clots or intracranial bleeding in patients with stroke, brain damage from a head injury, and other disorders. If the individual has abnormal results on a neurological examination, often a CT scan is performed to look for brain swelling, hemorrhage, or abscess which if present, could make a spinal tap unsafe.
  • Magnetic resonance imaging (MRI) uses computer-generated radio waves and a strong magnet to produce detailed images of body structures, including tissues, organs, bones, and nerves. Thee is no radiation involved in this test and it gives a much better picture of the actual brain tissue. this may not be available in the emergency setting so a CT scan is usually performed first in very ill individuals. The pictures, which are clearer than those produced by CT, can help identify brain and spinal cord inflammation, infection, tumors, eye disease, and blood vessel irregularities that may lead to stroke. A contrast dye may be injected prior to the test to reveal more detail.
Electroencephalography, or EEG, can identify abnormal brain waves by monitoring electrical activity in the brain through the skull. Among its many functions, EEG is used to help diagnose seizures or patterns that may suggest specific viral infections such as herpes virus, and to detect subclinical seizures which may contribute to abnormalities in level of consciousness in critically ill individuals.

How are these infections treated?

Persons who are suspected of having meningitis or encephalitis should receive immediate, aggressive medical treatment. Both diseases can progress quickly and have the potential to cause severe, irreversible neurological damage.
Antiviral drugs used to treat viral encephalitis include acyclovir and ganciclovir.
Anticonvulsants may be prescribed to stop or prevent seizures. Corticosteroids can reduce brain swelling. Individuals with breathing difficulties may require artificial respiration. 
Autoimmune causes of encephalitis are treated with additional immunosuppressant drugs and screening for tumors when appropriate.
Individuals should receive evaluation for comprehensive rehabilitation that might include cognitive rehabilitation, physical, speech, and occupational therapy once the acute illness is under control.

What is the prognosis for these infections?

Outcome generally depends on the particular infectious agent involved, the severity of the illness, and how quickly treatment is given. In most cases, people with very mild encephalitis or meningitis can make a full recovery, although the process may be slow.
Individuals who experience only headache, fever, and stiff neck may recover in 2-4 weeks. Those with bacterial meningitis typically show some relief 48-72 hours following initial treatment but are more likely to experience complications caused by the disease. In more serious cases, these diseases can cause hearing and/or speech loss, blindness, permanent brain and nerve damage, behavioral changes, cognitive disabilities, lack of muscle control, seizures, and memory loss. These patients may need long-term therapy, medication, and supportive care. The recovery from encephalitis is variable depending on the cause and extent of brain inflammation.

What research is being done?

The National Institute of Neurological Disorders and Stroke (NINDS), a component of the National Institutes of Health (NIH) within the U.S. Department of Health and Human Services, conducts and supports a wide range of research on neurological disorders, including meningitis and encephalitis. Current research efforts include gaining a better understanding of how the central nervous system responds to inflammation and to better understand the molecular mechanisms involved in the protection and disruption of the blood-brain barrier, which could lead to the development of new treatments for several neuroinflammatory diseases such as meningitis and encephalitis. A possible therapeutic approach under investigation involves testing neuroprotective compounds that block the damage that accumulates after the infection, and how the inflammation of meningitis and encephalitis can lead to potential complications including loss of cognitive function and dementia.

Where can I get more information?

For more information on neurological disorders or research programs funded by the National Institute of Neurological Disorders and Stroke, contact the Institute's Brain Resources and Information Network (BRAIN) at:
BRAIN
P.O. Box 5801
Bethesda, MD 20824
800-352-9424
http://www.ninds.nih.gov
Information also is available from the following organizations:

Organizations Supporting this Disease


    Meningitis Foundation of America, Inc.
    P.O. Box 1818
    El Mirage, AZ 85335
    supportmfa@musa.org
    http://musa.org/
    Tel: 480-270-2652
    National Meningitis Association
    P.O. Box 60143
    Ft. Myers, FL 33906
    support@nmaus.org
    http://www.nmaus.org
    Tel: 866-366-3662
    Fax: 877-703-6096
    NIAID Office of Communications and Government Relations
    National Institutes of Health, DHHS
    5601 Fishers Lane, MSC 9806
    Bethesda, MD 20892
    https://www.niaid.nih.gov/
    Tel: 301-496-5717
    "Meningitis and Encephalitis Fact Sheet", NINDS, 
    NIH Publication No. 04-4840
    Prepared by:
    Office of Communications and Public Liaison
    National Institute of Neurological Disorders and Stroke
    National Institutes of Health
    Bethesda, MD 20892

    OTHER ARTICLES ON AUTOIMMUNE ENCEPHALITIS



    Posted by at
    Labels: , , ,

    No comments:

    Post a Comment

    Subscribe to: Post Comments (Atom)