Dr. Balentine received his undergraduate degree from McDaniel College in Westminster, Maryland. He attended medical school at the Philadelphia College of Osteopathic Medicine graduating in1983. He completed his internship at St. Joseph's Hospital in Philadelphia and his Emergency Medicine residency at Lincoln Medical and Mental Health Center in the Bronx, where he served as chief resident.
Dr. Shiel received a Bachelor of Science degree with honors from the University of Notre Dame. There he was involved in research in radiation biology and received the Huisking Scholarship. After graduating from St. Louis University School of Medicine, he completed his Internal Medicine residency and Rheumatology fellowship at the University of California, Irvine. He is board-certified in Internal Medicine and Rheumatology.
Medical Author: Melissa
Conrad Stöppler, MD
Medical Editor:
Jay W. Marks, MD
West Nile virus was first observed in the U.S. during the summer of 1999 and
is believed to be permanently established (endemic) in the U.S. at this time. A
member of the flavivirusfamily, West Nile virus
is related to the St. Louis encephalitis virus that is also found in the U.S. West Nile virus is commonly
found in Africa, the Middle East, and in the western parts of Asia. It infects
mosquitoes, birds, horses, humans, and some other mammals.
West Nile fever develops two to 15
days following the bite of an infected mosquito and persists for a few days to a
few weeks.
In less than 1% of cases, West Nile virus
infection leads to severe illness that is referred to as "neuroinvasive" disease
since it affects the nervous system. This severe form of West Nile virus
infection results in an inflammation of the brain (encephalitis) or the meninges, tissues that cover the
brain and central nervous system(meningitis). A combination of the two
(meningoencephalitis) can also occur, and the disease can be fatal. People over
50 years of age, pregnantwomen,
infants, and those with weakened immune systems due to medications,
HIV, or cancerare at greatest risk for severe illness related to West Nile
virus infection.
Meningitis is an inflammation of the membranes
(called meninges) that surround the brain and spinal cord.
Anyone experiencing symptoms of encephalitis or meningitis should
see a doctor immediately.
What is encephalitis?
Encephalitis is an inflammation of the brain. There are many types of encephalitis, most of which are caused by infections. Most often these infections are caused by viruses. In addition to infections, encephalitis can also be caused by certain diseases that result in an inflammation of the brain.
What are encephalitis symptoms and signs?
The signs and symptoms of encephalitis can range from very mild symptoms to potentially life-threatening. Signs and symptoms of encephalitis include sudden fever, headache, vomiting,
visual sensitivity to light, stiff neck and back, confusion, drowsiness, unsteady gait, and irritability. Loss of consciousness, poor responsiveness, seizures, muscle weakness, sudden severe dementia and memory loss can also be found in patients with encephalitis.
Anyone experiencing symptoms of encephalitis should see a doctor
immediately.
What is meningitis?
Meningitis is an inflammation of the membranes (called meninges) that surround the brain and spinal cord. Meningitis may be caused by many different viruses and bacteria. It can also be caused by diseases that can trigger inflammation of tissues of the body without infection (such as systemic lupus erythematosus and Behcet's disease).
What are meningitis symptoms and signs?
The classic signs and symptoms of meningitis are headache, fever, and stiff neck (in adults and older children). Symptoms of meningitis may appear suddenly and can also include nausea and vomiting. Changes in behavior, such as confusion, sleepiness, and difficulty waking up, are
other important symptoms. In infants, symptoms of meningitis are often much less specific and may include irritability or tiredness, poor feeding, and fever.
Some types of meningitis can be deadly if not treated promptly.
Anyone experiencing symptoms of meningitis should see a doctor
immediately.
What is encephalomyelitis?
Encephalomyelitis is inflammation of both the brain and spinal cord.
Encephalomyelitis can be caused by a variety of conditions that lead
to irritation of the brain and spinal cord. Among the common causes
of encephalomyelitis are viruses which infect the nervous tissues
(for example, herpes zoster virus). People with encephalomyelitis can exhibit
combinations of the various symptoms of either encephalitis or
meningitis.
How are encephalitis and meningitis diagnosed?
Encephalitis or meningitis is suggested when the symptoms described above are present. The doctor diagnoses encephalitis or meningitis after a completing a thorough history (asking the patient questions) and examination. The examination includes special maneuvers to detect signs of inflammation of the membranes that surround the brain and spinal cord (meninges). Based on the history and examination, the doctor suggests specific tests to further help in determining the diagnosis.
Tests that are used in the evaluation of individuals suspected of having encephalitis or meningitis include evaluation of the blood for signs of infection and possible presence of bacteria, brain scanning (such as
CT scanning or MRI scan), and
cerebrospinal fluid analysis.
A lumbar puncture is the most common method of obtaining a sample of
the fluid in the spinal canal (the cerebrospinal fluid or CSF) for
examination. A lumbar puncture (an LP) is the insertion of a needle
into the fluid within the spinal canal. It is termed a "lumbar puncture" because the needle goes into the lumbar portion
of the back (the lower portion of the back). The needle passes between the bony parts of the spine until it reaches the cerebral spinal fluid. A small amount of fluid is then collected and sent to the laboratory for examination. The evaluation of the spinal fluid is usually necessary for the definite diagnosis and to help make optimal treatment decisions (such as the appropriate choice of antibiotics).
The diagnosis is confirmed by abnormal spinal fluid results and, in the case of an infection, by identifying the organism causing the infection. In patients with meningitis, the CSF fluid often has a low glucose (sugar) level and increased white blood cell count. In addition, the fluid can be used to identify some viral causes of meningitis (PCR or polymerase chain reaction) or be used to culture bacterial organisms causing the meningitis.
Lyme disease is a bacterial illness, which is spread by ticks when they bite the skin. Initially the disease affects the skin causing a reddish rash associated with flu-like symptoms. It takes weeks to months after the initial redness of the skin for its effects to spread throughout the body. Lyme disease can be treated with antibiotics. Lyme disease can be prevented by using tick avoidance techniques.
Hand-foot-and-mouth syndrome is clinical pattern consisting of a rash on the hands and feet, and in the mouth. Hand-foot-and-mouth syndrome is caused by various viruses including several types of the coxsackievirus. Other symptoms include sore throat, decreased appetite, irritability, and (or) fever.
Herpes simplex infections are common and when they appear around the mouth and lips, people often refer to them as "cold sores" and "fever blisters." Canker sores are different than cold sores. Air droplets can spread the virus, as can direct contact with the fluid from the blisters. Cold sore treatment include over-the-counter medication as well as prescription medications.
Coxsackie viruses may be divided into two groups. Type A causes hand, foot, and mouth disease and conjunctivitis, while type B causes pleurodynia. Both types sometimes cause meningitis, myocarditis, and pericarditis. There is no specific treatment for this disease.
Dementia is a significant loss of intellectual abilities such as memory capacity, severe enough to interfere with social or occupational functioning. There are different criteria classification schemes for dementias such as cortical, subcortical, progressive, primary, and secondary dementias. Other conditions and medication reactions can also cause dementia. Dementia is diagnosed based on a certain set of criteria. Treatment for dementia is generally focused on the symptoms of the disease.
An upper respiratory infection is a contagious infection of the structures of the upper respiratory tract, which includes the sinuses, nasal passages, pharynx, and larynx. Common causes of an upper respiratory infection include bacteria and viruses such as rhinoviruses, group A streptococci, influenza, respiratory syncytial, whooping cough, diphtheria, and Epstein-Barre. Examples of symptoms of upper respiratory infection include sneezing, sore throat, cough, fever, and nasal congestion. Treatment of upper respiratory infection are generally with OTC medication and home remedies.
Although a fever technically is any body temperature above the normal of 98.6 degrees F. (37 degrees C.), in practice a person is usually not considered to have a significant fever until the temperature is above 100.4 degrees F (38 degrees C.). Fever is part of the body's own disease-fighting arsenal: rising body temperatures apparently are capable of killing off many disease- producing organisms.
Group B strep are bacteria called Streptococcus agalactiae that may sometimes cause infections both in a pregnant woman and her newborn. Symptoms include fever, seizures, heart rate abnormalities, breathing problems, and fussiness. Intravenous antibiotics are used to treat group B strep infections.
Sepsis (blood poisoning) is a potentially deadly infection with signs and symptoms that include elevated heart rate, low or high temperature, rapid breathing and/or a white blood cell count that is too high or too low and has more than 10% band cells. Most cases of sepsis are caused by bacterial infections, and some cases are caused by fungal infections. Treatment requires hospitalization, IV antibiotics, and therapy to treat any organ dysfunction.
Neck pain (cervical pain) may be caused by any number of disorders and diseases. Tenderness is another symptom of neck pain. Though treatment for neck pain really depends upon the cause, treatment typically may involve heat/ice application, traction, physical therapy, cortisone injection, topical anesthetic creams, and muscle relaxants.
Epilepsy is a brain disorder in which the person has seizures. There are two kinds of seizures, focal and generalized. There are many causes of epilepsy. Treatment of epilepsy (seizures) depends upon the cause and type of seizures experienced.
Measles (rubeola) is a highly contagious disease that's caused by a virus. Symptoms include a rash, high fever, cough, runny nose, and red eyes. Treatment focuses on symptom relief. The disease can be prevented with the measles, mumps, and rubella vaccine.
Vancomycin-resistant enterococci (VRE) infection is the most common type of infection acquired by patients while hospitalized. Patients at risk for VRE are those who are already ill, and hospitalized, including individuals with diabetes, elderly, ICU patients, kidney failure patients, or patients requiring catheters. Enterococci can survive for months in the digestive tract and female genital tract. Other risk factors for acquiring VRE include those how have been previously treated with vancomycin and combinations of other antibiotics. Treatment of VRE is generally with other antibiotics other than vancomycin. Prevention of VRE can be achieved by proper hand hygiene.
Hydrocephalus is an abnormal buildup of cerebrospinal fluid (CSF) in the ventricles of the brain. The fluid is often under increased pressure and can compress and damage the brain. Symptoms of hydrocephalus vary with age, progression of the disease, and individual tolerance to the condition. Hydrocephalus is most often treated by surgery in which a shunt system is inserted.
Mumps is an acute viral illness caused by the mumps virus. Symptoms of mumps include fever, headache, muscle aches, tiredness, and loss of appetite; followed by swelling of the salivary glands.
Sinus headache is caused by a sinus infection or inflammation of the sinus cavities. The primary symptom of a sinus infection is pain and increasing pressure overlying the area and associated tenderness to the touch. Treatment of a sinus headache depends on the cause.
Optic neuritis is inflammation of the optic nerve, the structure that connects the eye to the brain. The precise cause of optic neuritis is unknown, but it is thought to be a type of autoimmune disorder. Optic neuritis most commonly develops due to an autoimmune disorder that may be triggered by a viral infection.
Kawasaki disease is a rare children's disease characterized by a fever that lasts more than five days and at least four of the following five symptoms are present: rash, swollen neck lymph gland, red tongue, swelling or redness of the hands or feet, and conjunctivitis. High doses of aspirin are used to treat Kawasaki disease. Cortisone and antiinflammatory drugs may also be used during treatment.
Group A streptococcal infections are caused by group A streptococcus, a bacteria that causes a variety of health problems, including strep throat, impetigo, cellulitis, erysipelas, and scarlet fever. There are more than 10 million group A strep infections each year.
Listeria is a type of bacteria that can cause food poisoning. Listeriosis symptoms include diarrhea, nausea and fever. Pregnant women are 20 times more likely than other healthy adults to get listeriosis. Listeria infection is treated with antibiotics.
Leptospirosis is an infectious disease caused by bacteria. The illness progresses in two phases. Symptoms in the first phase include headache, muscle aches, eye pain with bright lights, chills, and fever. Symptoms in the second phase begin after a few days of feeling well and include fever, aches, and a stiff neck. Some people develop meningitis and abdominal pain.
Brain lesions (lesions on the brain) are caused by trauma, inflammation, autoimmune diseases, cancers, other diseases, stroke, bleeding, pituitary adenomas, and cerebral palsy. Symptoms of brain lesions include headache, nausea, fever, neck pain and stiffness, affected vision and speech, weakness or paralysis to one side of the body. Diagnosis of brain lesions is generally with imaging studies like CT or MRI scans. Treatment and prognosis of brain lesions depends on the cause of the lesion.
Medical shock is a life-threatening medical condition. There are several types of medical shock, septic shock, anaphylactic shock, cardiogenic shock, hypovolemic shock, and neurogenic shock. Causes of shock include heart attack, heart failure, heavy bleeding (internal and external), infection, anaphylaxis, spinal cord injury, severe burns, chronic vomiting or diarrhea. Low blood pressure is the key sign of sock. Treatment is dependant upon the type of shock.
Spina bifida is the most common neural tube defect in the United States. There are four types of spina bifida; 1) occulta, 2) closed neural tube defects, 3) meningocele, and 4) myelomeningocele. The cause of spina bifida is not known. Theories include genetic, nutritional, and environmental factors. Lack of folic acid during pregnancy is highly suspected. Symptoms of spina bifida vary from individual to individual. Treatment depends on the type of spina bifida the person suffers.
Becoming infected with chickenpox during pregnancy could cause birth defects in your unborn child. Likewise, shingles could also cause problems for your unborn child. If you are pregnant and haven't had chickenpox, avoid exposure to infected people. Zostavax, the shingles vaccine, can reduce the incidence of shingles by half. Women should wait at least three months after receiving the vaccine before trying to get pregnant.
Drug resistance (antimicrobial resistance) is the ability of bacteria, fungi, parasites, and viruses to grow, even in the presence of a drug that would normally kill it (or limit it's growth). Drug resistance is a growing problem, particularly for infections such as MRSA, VRE (vancomycin-resistant enterococci), tuberculosis, HIV, STDs, gonorrhea, flu, pneumonia, malaria, E. coli, salmonella, Campylobacter, which causes diarrhea and gastroenteritis. Learn how to protect yourself from resistance to drugs.
West Nile virus (West Nile encephalitis) is a brain infection caused by a virus. People become infected with the virus after they're bitten by a mosquito that has fed off of a bird that's infected with the West Nile virus. Symptoms in humans include fever, headache, rash, body ache, and swollen lymph nodes.
Febrile seizures, or convulsions caused by fever in small children or infants can be frightening, however, in general are harmless. Febrile seizures is not epilepsy. It is estimated that one in every 25 children will have at least one febrile seizure. It is important to know what to do to help your child if he/she has a febrile seizure.
Naegleria fowleri is an amoeba found in freshwater and soil. Infection results when the amoeba enters the nose and travels to the brain and spinal cord, causing primary amebic meningoencephalitis, which destroys brain tissue.
Few experiences match the drama of a convulsive seizure. A person having a severe seizure may cry out, fall to the floor
unconscious, twitch or move uncontrollably, drool, or even lose bladder control. Within minutes, the attack is over, and the person regains consciousness but is exhausted and dazed. This is the image most people have when they hear the word epilepsy. However, this type of seizure -- a
generalized tonic-clonic seizure -- is only one kind of epilepsy. There are many other kinds, each with a different set of symptoms.
Epilepsy was one of the first brain disorders to be described. It was mentioned in ancient Babylon more than 3,000 years ago. The strange behavior caused by some seizures has contributed through the ages to many superstitions and prejudices. The word epilepsy is derived from the Greek word for "attack." People once thought that those with epilepsy were being visited by demons or gods. However, in 400 B.C., the early...