Wednesday 14 September 2011

Infectious Mononucleosis (Mono)

Infectious mononucleosis (mono) facts

  • Infectious mononucleosis (mono) is a contagious illness caused by the Epstein-Barr virus (EBV).
  • The infection can be spread by saliva, and the incubation period for mono is four to eight weeks.
  • Most adults have laboratory evidence (antibodies against the EBV) indicative of a previous infection with EBV and are immune to further infection.
  • The symptoms of mono include fever, fatigue, sore throat, and swollen lymph nodes.
  • The diagnosis of mono is confirmed by blood tests.
  • Mono can cause liver inflammation (hepatitis) and enlargement of the spleen.
  • People who have had mono can continue to shed virus particles in their saliva during reactivations of the viral infection throughout their lifetime.
  • Vigorous contact sports should be avoided in the illness and recovery phase to prevent rupture of the spleen.

What is infectious mononucleosis?

Infectious mononucleosis, "mono," "kissing disease," and glandular fever are all terms popularly used for the very common infection caused by the Epstein-Barr virus (EBV). EBV is a member of the herpesvirus family. The characteristic symptoms of infection with EBV include fever, fatigue, malaise, and sore throat. The designation "mononucleosis" refers to an increase in a particular type of white blood cells (lymphocytes) in the bloodstream relative to the other white blood cells as a result of the EBV infection.
The disease was first described in 1889 and was referred to as "Drüsenfieber," or glandular fever. The term infectious mononucleosis was first used in 1920 when an increased number of lymphocytes were found in the blood of a group of college students who had fever and symptoms of the condition.

What is the cause of mono?

The EBV that causes mono is found throughout the world. By the time most people reach adulthood, an antibody against EBV can be detected in their blood. In the U.S., up to 95% of adults 35-40 years of age have antibodies directed against EBV. This means that most people, sometime in their lives, have been infected with EBV. The body's immune system produces antibodies to attack and help destroy invading viruses and bacteria. These specific antibodies can be detected in the blood of people who have been infected.
When infection occurs in childhood, the virus most often produces no symptoms. It is estimated that only about 10% of children who become infected with EBV develop the illness. Likewise, probably because of immunity from prior infection, adults typically do not develop the illness. Most cases of infectious mononucleosis occur in the 15-24 age group.
While there are other illnesses falling under the broad classification of mononucleosis that can cause similar symptoms (cytomegalovirus [CMV] infection is one example) and an increase in blood lymphocytes, the form caused by the EBV is by far the most common.

What are the risk factors for mono?

The EBV can infect any person. As previously discussed, the majority of people have become infected with the virus by the time that they reach adulthood, and the majority of these infections produce no symptoms or are not recognized as mono. Mono is most often diagnosed in adolescents and young adults, with a peak incidence at 15-17 years of age. However, it can also be seen in children. Generally, the illness is less severe in young children and may mimic the symptoms of other common childhood illnesses, which may explain why it is less commonly diagnosed or recognized in this younger age group.
Infectious Mononucleosis Symptoms and Signs
Infectious mononucleosis symptoms and signs

How is mono transmitted or spread?

Mono is spread by person-to-person contact. Saliva is the primary method of transmitting mono, which leads to the infection of B lymphocytes in the mouth and throat. Infectious mononucleosis developed its common name of "kissing disease" from this prevalent form of transmission among teenagers. It typically takes between four to eight weeks for symptoms of mono to appear after the initial infection with EBV. A person with mono can also pass the disease by coughing or sneezing, causing small droplets of infected saliva and/or mucus to be suspended in the air which can be inhaled by others. Sharing food or beverages from the same container or utensil can also transfer the virus from one person to another since contact with infected saliva may result.
Most people have been exposed to the virus as children, and as a result of the exposure, they have developed immunity to the virus. It is of note that most people who are exposed to the EBV don't ever develop mononucleosis. The incubation period for mono, meaning the time from the initial viral infection until the appearance of symptoms, is between four and eight weeks. During an infection, a person is likely able to transmit the virus to others for at least a few weeks and possibly longer, even after symptoms have disappeared (see below).
Research has shown that, depending on the method used to detect the virus, anywhere from 20%-80% of people who have had mononucleosis and have recovered will continue to secrete the EBV in their saliva for years due to periodic "reactivations" of the viral infection. Since healthy people without symptoms also secrete the virus during reactivation episodes throughout their lifetime, isolation of people infected with EBV is not necessary. It is currently believed that these healthy people, who nevertheless secrete EBV particles, are the primary reservoir for transmission of EBV among humans.

What are the symptoms of mono?

The initial symptoms of mono are
  • a general lack of energy or malaise,
  • fatigue,
  • a loss of appetite,
  • chills.
These initial symptoms can last from one to three days before the more intense symptoms of the illness begin. The more common intense symptoms include
  • a severe sore throat,
  • fever, which may be persistent,
  • swollen lymph nodes (glands) in the neck area.
It is typically the severe sore throat that prompts people to contact their doctor.

What are the signs of mono?

In addition to a fever from 102 F-104 F, the most common signs of mono are
  • a very reddened throat and tonsils,
  • swollen lymph glands in the neck that typically occur on both sides.
The tonsils have a whitish coating in at least one-third of the cases. The spleen (sometimes referred to as the body's biggest lymph node) is an organ found in the left upper abdomen underneath the rib cage, which becomes enlarged or swollen in about 50% of patients with mono. An enlarged liver and abnormalities in liver function tests (blood tests) may be detected (see Complications, below). About 5% of patients have a splotchy red rash over the body, which has a similar appearance to the rash of measles. Early in the course of disease (over the first few days of illness), a temporary swelling (edema) of both upper eyelids may appear.

What is the usual course and treatment of mono?

In most cases of mono, no specific treatment is necessary. The illness is usually self-limited and passes much the way other common viral illnesses resolve. Treatment is directed toward the relief of symptoms. Available antiviral drugs have no significant effect on the overall outcome of mono and may actually prolong the course of the illness. Occasionally, Strep throat occurs in conjunction with mono and is best treated with penicillin or erythromycin (E-Mycin, Eryc, Ery-Tab, PCE, Pediazole, Ilosone). Ampicillin (Omnipen, Polycillin, Principen) and amoxicillin (Amoxil, DisperMox, Trimox) should be avoided if there is a possibility of mono since up to 90% of patients with mono develop a rash when taking these medications. They may then be inappropriately thought to have an allergy to penicillin.
For the most part, supportive or comfort measures are all that is necessary. Acetaminophen (Tylenol) can be given for fever and any headache or body aches. A sufficient amount of sleep and rest is important. The throat soreness is worst during the first five to seven days of illness and then subsides over the next seven to 10 days. The swollen, tender lymph nodes generally subside by the third week.
A feeling of fatigue or tiredness may persist for months following the acute phase of the illness. It is recommended that patients with mono avoid participation in any contact sports for three to four weeks after the onset of symptoms to prevent trauma to the enlarged spleen. The enlarged spleen is susceptible to rupture, which can be life threatening. Cortisone medication is occasionally given for the treatment of severely swollen tonsils or throat tissues which threaten to obstruct breathing.
Patients can continue to have virus particles present in their saliva for as long as 18 months after the initial infection. When symptoms persist for more than six months, the condition is frequently called "chronic" EBV infection. However, laboratory tests generally cannot confirm continued active EBV infection in people with "chronic" EBV infection.

Bird Flu (Avian Influenza, Avian Flu)

Bird flu facts

  • Bird flu refers to strains of influenza that primarily affect wild and domesticated birds.
  • Bird flu is also known as avian flu or avian influenza.
  • Although bird flu is contagious and spreads easily among birds, it is uncommon for it to be transmitted to humans.
  • In the late 1990s, a new strain of bird flu arose which was unusually severe ("highly pathogenic"), resulting in the deaths of hundreds of millions of birds, including poultry.
  • Control efforts, including culling infected flocks and vaccinating healthy birds, have limited the spread of highly pathogenic bird flu.
  • In 2011, a mutated strain of highly pathogenic bird flu appeared, which is concerning because the existing poultry vaccines are not very effective against the new strain.
  • Human infection with the highly pathogenic strain of bird flu is uncommon, with fewer than 600 cases reported since 1997.
  • Human infection occurs primarily in people who have close contact with sick poultry in countries where the virus is found. There have been isolated cases of human-to-human transmission.
  • Human infection with bird flu is fatal in approximately 60% of cases.
  • Bird flu from the highly pathogenic strain is not found in the United States at this time.

What is bird flu?

Bird flu (avian influenza) is a disease caused by an influenza virus that primarily affects birds. In the late 1990s, a new strain of bird flu arose that was remarkable for its ability to cause severe disease and death, especially in domesticated birds such as ducks, chickens, or turkeys. As a result, this strain was called highly pathogenic (meaning very severe) avian influenza.
Since the identification of highly pathogenic influenza, infected birds have been found in Asia, Europe, the Middle East, and Africa. Careful control measures, including destroying infected flocks and vaccinating healthy birds, have reduced the number of cases, but the virus continues to exist in poultry flocks in areas of Asia and Africa. Bird flu from the highly pathogenic strain is not found in the United States at this time.
The virus spreads from bird to bird through infected birds shedding the virus in their saliva, nasal secretions, and droppings. Healthy birds get infected when they come into contact with contaminated secretions or feces from infected birds. Contact with contaminated surfaces such as cages might also allow the virus to transfer from bird to bird. Symptoms in birds range from mild drops in egg production to failure of multiple major organs and death.
The first human case of illness from highly pathogenic avian influenza was identified in 1997, and more than 560 cases have been identified since then, with deaths worldwide exceeding 300. Human cases of highly pathogenic bird flu have been largely confined to Southeast Asia and Africa. However, mutations often occur in the virus, and it is possible that some mutations could create a more contagious virus that could cause a regional epidemic or a worldwide pandemic of bird flu among humans. Fortunately, the mutations that have occurred to date have not made the virus more contagious, although the concern remains.

What causes bird flu?

Bird flu is caused by strains of the influenza virus that have evolved to be specially adapted to enter avian cells. There are three main types of influenza: A, B, and C. The virus that causes bird flu is an influenza A type with eight RNA strands that make up its genome. Influenza viruses are further classified by analyzing two proteins on the surface of the virus. The proteins are called hemagglutinin (H) and neuraminidase (N). There are many different types of hemagglutinin and neuraminidase proteins. The current highly pathogenic bird flu virus has type 5 hemagglutinin and type 1 neuraminidase. Thus, it is a "H5N1" influenza A virus.
There are many types of influenza viruses, and most prefer to live in a limited number of animals. Thus, swine flu primarily infects swine and bird flu primarily infects birds. Human influenza is best adapted to humans. A few cases may occur in an accidental host, such as when people who have extensive contact with sick birds get the bird flu. In addition to humans and birds, we know that pigs, tigers, leopards, ferrets, and domestic cats can sometimes be infected with avian influenza viruses.
Influenza viruses mutate easily and often. These mutations can arise spontaneously in a single virus or can occur when two different influenza strains get close enough together to exchange genetic material. There are two major types of mutations in influenza viruses: antigenic shifts, where large RNA segments are interchanged between different influenza virus type, and antigenic shifts, where small RNA sequences are changed. The antigenic shifts are usually responsible for developing new strains. For example, the 2009 swine flu pandemic was caused by a virus that included genetic material from pig influenza, avian influenza, and human influenza strains. New mutations can allow the virus to evade the body's immune system and makes older vaccines ineffective. In 2011, one strain of the highly pathogenic avian influenza virus mutated in this way, making the existing vaccine used against avian flu ineffective against the new strain. Sometimes a flu virus will mutate in a way that makes it able to infect a new species.
Serious pandemic influenza occurs when a relatively new strain of the influenza virus arises that is highly contagious to humans. The most deadly pandemic in modern history was the 1918 influenza, also known as the Spanish flu (although it did not originate in Spain). The 1918 virus spread rapidly and killed tens of millions of people worldwide. Mortality was especially high in healthy young adults. Although the 1918 virus was a human influenza virus it, had many genes that likely came from a strain of bird flu. One reason that health officials carefully watch for and try to limit human contact with birds that develop avian flu is to avoid chances for a new strain to arise that may prefer to develop in human tissue.

What are risk factors for bird flu?

Humans may get bird flu from contact with infected birds (chickens, for example) or their droppings or surfaces with infected droppings. Risk factors include caring for sick birds, killing sick birds, and preparing sick birds for consumption. Despite the large number of people who have contact with poultry every day in the world, human cases of bird flu remain rare. This highlights how difficult it is for the bird flu virus to infect human cells, but mutations like antigenic shifts may reduce such difficulties.
Although direct contact with sick poultry poses the highest risk, indirect exposure to bird feces is also a risk. Thus, contact with unwashed eggs from sick birds or water contaminated by poultry feces poses a potential risk of disease.
Human to human spread has occurred in isolated cases. Thus, caring for a person infected with bird flu is also a risk factor for the disease. There is a theoretical risk in laboratory workers who handle the avian flu virus. One alleged incident in 2009 occurred when a company inadvertently sent live avian flu virus samples to research laboratories, which subsequently were used to vaccinate ferrets. The contaminated vaccine did not result in any human cases of infection.

What are bird flu symptoms and signs?

Symptoms occur approximately two to eight days after exposure, on average. Infected people experience typical flu-like symptoms, including fever, cough, sore throat, and muscle aches. Some people also have nausea, vomiting, diarrhea, or eye infections. This can progress to pneumonia and even respiratory failure. Bird flu causes a very aggressive form of pneumonia (acute respiratory distress syndrome or ARDS) that is often fatal.

How is bird flu diagnosed?

Routine tests for human influenza A will be positive in patients with bird flu but are not specific for the avian virus. To make a specific diagnosis of bird flu, specialized tests are needed. In the United States, local health departments and the Centers for Disease Control and Prevention can provide access to the specialized testing. The virus can be detected in sputum by several methods, including culture or polymerase chain reaction (PCR). Culture should be done in laboratories that have an appropriate biosafety certification. PCR detects nucleic acid from the influenza A virus. Specialized PCR testing is available in reference laboratories to identify avian strains.
During and after infection with bird flu, the body makes antibodies against the virus. Blood tests can detect these antibodies, but this requires one sample at the onset of disease and another sample several weeks later. Thus, results are not available until the patient has recovered or died.

What is the treatment for bird flu?

Because of the small number of human cases, it has not been possible to conduct rigorous treatment trials for bird flu. The current recommendation from the World Health Organization is to use an antiviral medication called oseltamivir (Tamiflu). In Sept. 2011, the CDC stated the following: "Two other antiviral medications, oseltamivir and zanamivir, would probably work to treat influenza caused by H5N1 virus, but additional studies still need to be done to demonstrate their effectiveness."

Cholesterol Test

High cholesterol facts

  • Cholesterol is a naturally occurring substance in the body that is an important part of normal body function.
  • Cholesterol has two main types: HDL, or good cholesterol, that protects against heart disease, stroke and peripheral vascular disease; and LD, or bad ,cholesterol, that increases the risk of these conditions.
  • Cholesterol tests measure total cholesterol as well as HDL and LDL levels in the blood. Triglycerides, another type of fat present in the bloodstream, may also be measured.
  • Cholesterol tests are usually ordered and blood drawn in the health care provider's office. There are also home test kits available. It is important to be fasting for the tests to be accurate. Typically, a fasting test is performed first thing in the morning before the individual has eaten anything for the day.
  • Cholesterol test results should be discussed with the health care provider to determine if treatment of high cholesterol is necessary to decrease the risk of heart disease and stroke.

What is cholesterol?

Cholesterol is a naturally occurring fat that the body needs to produce important structures and chemicals. It is one of the main components of cell membranes, the outer lining that protects the internal structures that make body cells work and function properly. Cholesterol is also a building block for many of the hormones in the body including mineralocorticoids that control electrolyte levels in the body, glucocorticoids involved in carbohydrate metabolism, and sex hormones including testosterone, estrogen, and progesterone. Cholesterol is one of the building blocks that assists in forming Vitamin D in the body. Vitamin D is responsible for calcium metabolism in the body.
There are two important types of cholesterol, high density lipoprotein (HDL) and low density lipoprotein (LDL). LDL is the bad cholesterol that deposits in arteries when too much is present. HDL is considered the good cholesterol because it can bind to LDL cholesterol and return it to the liver where it can be removed from the body.
While most of the cholesterol in the body is obtained through the foods we eat, it is also produced in the liver to meet the body's demands. The body attempts to regulate the amount of total cholesterol, but when too much cholesterol is present, the excess can be deposited in arteries throughout the body. This leads to artery narrowing and increases the risk of heart attack, stroke, and peripheral vascular disease. Elevated LDL levels increase the risk of these diseases, and elevated HDL levels decrease the risk.

What does a cholesterol test measure?

Cholesterol tests are blood tests that measure the amount of cholesterol in the body. The health care provider may order only a cholesterol test with results showing total cholesterol, HDL, and LDL levels; or the health care provider also may order a lipid profile. In addition to cholesterol levels, the lipid profile test will also measure triglyceride levels, another fatty substance found in the blood.

How do I prepare for a cholesterol test?

For the best and most accurate results, it is important to fast for many hours before the cholesterol blood test is taken. Each laboratory has its own guidelines for not eating, and the fast may range from 9-16 hours. It is acceptable to drink water.

Do I need to call my doctor for my test results?

It usually takes a day or two from the time the blood is drawn until your health care provider receives the results of the cholesterol test. Ideally, the health care provider will contact you with those results and explain their significance. However, if you have not been contacted in a short period of time, it is reasonable to contact your health care provider and ask for the test results.
There are home cholesterol test kits available that have been U.S. FDA approved, but their accuracy is not necessarily as good as that of a certified laboratory. These tests usually measure total cholesterol only, but some also can measure HDL, LDL and cholesterol. If you use one of the home kits, it is wise to discuss the results with your health care provider.
The purpose of the cholesterol blood test is to determine whether treatment is needed for high cholesterol. That treatment may include dietary and lifestyle modifications, medications, or both to control cholesterol levels and decrease the risk of heart disease, stroke, and peripheral vascular disease.

How do I interpret my cholesterol test results?

Cholesterol levels are but one of the risk factors for heart disease, stroke, and peripheral vascular disease. It is important to control cholesterol levels to minimize risk just as it is important to control diabetes, high blood pressure, and avoid smoking.
Guidelines for cholesterol levels have been developed by many health organizations including the American Heart Association. It is important to remember that tests may need to be repeated over time to help monitor treatment and disease risk prevention.

Total cholesterol
Less than 200 mg/dL: desirable
200-239 mg/dL: borderline high risk
240 and over: high risk

HDL (high density lipoprotein)
Less than 40 mg/dL (men), less than 50 mg/dL (women): increased risk of heart disease
Greater than 60mg/dL: some protection against heart disease

LDL (low density lipoprotein)
Less than 100 mg/dL: optimal
100-129 mg/dL: near optimal/above optimal
130-159 mg/dL: borderline high
160- 189 mg/dL: high
190 mg/dL and above: very high

Triglycerides
Less than n150 mg/dL: normal
150-199 mg/dL: borderline to high
200-499mg/dL: high
Above 500 mg/dL: very high

Brain Aneurysm (Cerebral Aneurysm)

Brain aneurysm facts

  • Blood to the brain is supplied by four major blood vessels that join together at the Circle of Willis at the base of the brain. Smaller branch arteries leave the circle to supply brain cells with oxygen and nutrients.
  • Artery junction points may become weak, causing ballooning of the blood vessel wall that can form a small sac or aneurysm.
  • Cerebral aneurysms are common, but most are asymptomatic and are found incidentally at autopsy.
  • Aneurysms can leak or rupture causing symptoms from severe headache to stroke-like symptoms, or death.
  • The health care practitioner needs to maintain a high incidence of suspicion to make the diagnosis, since many patients may have an initial small leak of blood causing symptoms before a catastrophic bleed occurs.
  • Diagnosis of a brain aneurysm may require CT scans, lumbar puncture, or angiography.
  • Treatment to repair the aneurysm may involve neurosurgery to put a clip across the weak blood vessel wall or clipping by interventional radiology.

What is a brain aneurysm and what causes a brain aneurysm?

The Circle of Willis is the junction of the four many arteries that supply the brain with nutrition (oxygen and glucose), two carotid arteries and two vertebral arteries. This loop of arteries is located at the base of the brain and sends out smaller branch arteries to all parts of the brain. The junctions where these arteries come together may develop weak spots. These weak spots can balloon out and fill with blood, creating the outpouchings of blood vessels known as aneurysms. These sac-like areas may leak or rupture, spilling blood into surrounding tissues.
Aneurysms have a variety of causes including high blood pressure and atherosclerosis, trauma, heredity, and abnormal blood flow at the junction where arteries come together.
There are other rare causes of aneurysms. Mycotic aneurysms are caused by infections of the artery wall. Tumors and trauma can also cause aneurysms to form. Drug abuse, especially cocaine, can cause the artery walls to inflame and weaken.
Brain aneurysms (aneurysms within arteries in the brain) are a common occurrence. At autopsy, incidental asymptomatic aneurysms are found in more than 1% of people. Most aneurysms remain small and never become an issue or are diagnosed. Some, however, may gradually become larger and exert pressure on surrounding brain tissue and nerves and may be diagnosed because of symptoms such as:
  • headache,
  • numbness, or weakness of one side of the face,
  • a dilated pupil, or
  • change in vision.
The greater concern is a brain aneurysm that leaks or ruptures, and potentially causes stroke or death. Bleeding leaks into one of the membranes that covers the brain and spinal canal and is known as a subarachnoid hemorrhage (sub= beneath + arachnoid=one of the brain coverings + hemorrhage=bleeding).

What are the signs and symptoms of brain aneurysm?

The headache associated with a leaking aneurysm is severe. Blood is very irritating to the brain and causes significant pain. Patients may describe the "worst headache of their life," and the health care practitioner needs to have an appreciation of brain aneurysm as a potential cause of this type of pain. The headache may be associated with nausea, vomiting, and change in vision. A subarachnoid hemorrhage also causes pain and stiffness of the neck.

How is brain aneurysm diagnosed?

The diagnosis of brain aneurysm begins with a high index of suspicion by the health care practitioner. The history of the headache, an acute onset of the worst headache of the patient's life, associated with a stiff neck and an ill-appearing patient on physical examination, typically lead the health care practitioner to order a CT (computerized tomography) scan of the head. This will show a subarachnoid hemorrhage in more than 90% of cases of ruptured aneurysm. In the few cases that are not recognized by CT, the health care practitioner may consider performing a lumbar puncture (LP, or spinal tap) to identify blood in the cerebrospinal fluid that runs in the subarachnoid space.
If the CT or the LP reveals the presence of blood, angiography is performed to identify where the aneurysm is located and to plan treatment. Angiography (angio=artery +graphy= picture) is a procedure in which a small flexible tube is threaded into one of the brain's arteries, and dye is injected while pictures are taken. Newer technology allows angiography to be done in association with CT or magnetic resonance imaging (MRI).
Though the symptoms may suggest a brain aneurysm, other diagnoses may need to be considered. Migraine headache, meningitis, tumor, and stroke all may cause neurologic symptoms. Based on the patient's presentation, the health care practitioner will need to decide which tests and studies to use to establish the correct diagnosis.

What is the treatment for brain aneurysm?

Treatment for a symptomatic aneurysm is to repair the blood vessels. Clipping and coiling are two treatment options.
  • Clipping: A neurosurgeon can operate on the brain by cutting open the skull, identifying the damaged blood vessel and putting a clip across the aneurysm. This prevents blood from entering the aneurysm and causing further growth or blood leakage.
  • Coiling: A neurosurgeon or interventional radiologist can thread a tube through the arteries, as with an angiogram, identify the aneurysm, and fill it with coils of platinum wire or with latex. This prevents further blood from entering the aneurysm and resolves the problem.
Both these options have the risk of damaging the blood vessel and causing more bleeding, damaging nearby brain tissue, and causing the surrounding blood vessels to go into spasm; depriving brain tissue of blood supply and causing a stroke.
Prior, during, and after surgery, attention is paid to protect the brain and its blood vessels from potential further damage. Vitals signs are monitored frequently, and heart monitors are used to watch for abnormal heart rhythms. Medications may be used to prevent blood vessel spasm, seizure, agitation, and pain.

What is the outcome of brain aneurysm?

Brain aneurysms are deadly. About 10% of patients with a ruptured aneurysm die before receiving medical care. If untreated, another 50% will die within a month, with 25% of patients sustaining another bleeding episode within a week. Aside from the bleeding issues, there is significant risk of artery spasm leading to stroke.
Survival rates are increased by early presentation to the hospital, early aneurysm repair, and control of potential blood vessel spasm with medications.

What are future directions for the treatment of brain aneurysm?

For those who survive an initial aneurysm rupture, blood vessel spasm (vasospasm) may be the villain in causing continued brain damage. Experiments to develop new drugs to control vasospasm are ongoing. Molecules that can cause spasm are being identified, and antibodies may be able to be produced to blunt their effect.
Studies are also looking at the possibility that brain aneurysms may be hereditary, and perhaps screening of high-risk populations may be possible in the future.


Transient Ischemic Attack

What is the treatment for a transient ischemic attack (TIA)?

TIA Therapy
Treatment for a transient ischemic attack is aimed at preventing a second stroke. Since there is no way of determining the severity of future episodes, and no guarantee that the symptoms will resolve, prevention of a future TIA or CVA is crucial.
Treatment guidelines address a variety of targeted goals.
Antiplatelet therapy
  • If the patient was not taking aspirin when the TIA occurred, it usually is started at a dose of 325mg per day.
  • If the patient was taking aspirin, another antiplatelet drug called dipyridamole may be added. Aggrenox is a combination of aspirin and dipyridamole. Headache is often a side effect.
  • If the patient cannot tolerate aspirin because of allergy or stomach upset clopidogrel (Plavix) may be used.
High blood pressure therapy
  • Even if the patient does not have hypertension or high blood pressure, there may be benefit in taking anti-hypertensive medications.  
  • Two classes of drugs are recommended to be started at the same time, a diuretic and an ACE inhibitor.
  • The goal for normal blood pressure is 120/80.
Cholesterol lowering therapy
  • Guidelines recommend that a statin drug be started, even if cholesterol levels are normal. Simvastatin (Zocor) is the most commonly recommended medication, but new guidelines limit the amount prescribed per day because of the risk of liver side effects.
Risk modification
Smoking, excessive alcohol, obesity and lack of physical activity are considered risks for future stroke. The following recommendations are now suggested:
  • Smoking: Counseling, smoking cessation aids like nicotine gum or medications like varenicline (Chantix) should be considered. Environmental smoke should be avoided.
  • Alcohol: Intake should be limited to two or fewer drinks a day for men and one or less for women.
  • Obesity: Overweight people should try to lose weight using a combination of diet, exercise and counseling. The goal is a BMI of 18.5-24.9 and a waist line of 35 inches or less for women and 40 inches or less for men.
  • Exercise: 30 minutes of moderate exercise daily is recommended for those who are able. For patients with disabilities, a tailored exercise program to their capabilities should be arranged. 

What is the prognosis for transient ischemic attack (TIA)?

A transient ischemic attack should be considered a major warning sign of an impending future stroke. Up to 10% of people will experience a stroke within three months of TIA. Since there is no way of predicting that stroke-like symptoms will resolve, the patient and family need to be educated should symptoms occur, they need to access medical care emergently activating the emergency medical services system and calling 911.
If a stroke occurs, there is a very short period of time where thrombolytic (clot dissolving) drugs, (for example, alteplase [TPA]), can be used to reverse a stroke. In most hospitals, the drug can only be given within 4 1/2 hours of onset of stroke symptoms. In that time frame, the patient needs to get to the hospital, the diagnosis needs to be made, laboratory tests and head CT scans need to be performed, neurologic consultation needs to occur, and the drug administered. The longer the delay, there is a higher the risk that the drug won't work and that complications such as bleeding into the brain will occur.
Specialized interventional radiologists can inject TPA directly into the clot that has blocked the blood vessel in the brain. This can extend the time frame to six hours, but currently this treatment is not widely available.
TIAs should be considered the equivalent of angina of the brain. In heart disease, angina is the heart pain that warns of potential heart attack. When heart muscle is damaged, it cannot be replaced or repaired. Similarly, brain tissue is at risk when there is decreased blood supply and it, too, cannot be replaced.

Transient Ischemic Attack (TIA, Mini-Stroke)

Transient ischemic attack (TIA) facts

  • A transient ischemic attack (TIA) is a brief interruption of blood flow to part of the brain that causes temporary stroke like symptoms.
  • The risks for TIA are the same as for heart attack, stroke, and peripheral artery disease, and include smoking, high blood pressure, high cholesterol, diabetes, and family history.
  • The artery blockage may occur because of a ruptured plaque due to atherosclerosis or hardening of the arteries, debris that floats downstream from narrowed carotid arteries or blood clots (emboli) that form (often in the heart) and travel to block an artery in the brain.
  • Since TIAs resolve on their own, the goal for treatment is to minimize the risk of future TIAs and stroke. Treatment involves looking for the reason why the TIA occurred.
  • Treatment may include aspirin or other anti-platelet medications like Aggrenox or clopidogrel (Plavix).
  • It is important to educate the patient and family that should another stroke-like event occur, 911 must be called and emergency medical services activated, since there is no guarantee that symptoms will resolve.

What is a transient ischemic attack (TIA)?

The primary role of the brain is to send signals to the body for motor function and to receive signals through the five senses (sight, hearing, touch, smell, and taste), and to respond to them. The brain processes information through conscious thought, and unconsciously through nerve systems that control basic bodily functions, like heart rate, breathing, and temperature control.
In simple terms:
  • The brain is arranged so that the right side of the brain controls the left side of the body, and the left side of the brain controls the right of the body.
  • Vision is located in the back of the brain (occiput), and balance and coordination are located at the bottom of the brain (cerebellum).
  • Blood supply to the brain comes from the carotid arteries that are located in the front of the neck, and the vertebral arteries that run in the back of the neck through small canals in the bony spine (vertebrae) of the neck.
  • All of these connect at a junction of blood vessels located in the base of the brain (called the Circle of Willis), and from there smaller arteries supply the brain with oxygen and nutrients.
When a portion of the brain loses its blood supply, it can become damaged and stop functioning. When a portion of the brain does not function, the part of the body that it controls also stops working. This is called a stroke or a cerebrovascular accident (CVA). If the brain is able to regain its blood supply quickly, then the CVA symptoms may resolve; this is known as a transient ischemic attack (TIA). A TIA is similar to a stroke that resolves by itself because of a temporary lack of oxygen to a portion of the brain.

What are the causes of transient ischemic attack (TIA)?

Loss of blood supply to portions of the brain can occur for a variety of reasons. A blood vessel can become blocked, and blood supply to a part of the brain is lost, or a blood vessel can leak blood into the brain (brain hemorrhage). Most commonly however, the blood vessel is blocked. The blockage can be caused by a blood clot that forms in the blood vessel (thrombosis) or it can be caused by a clot or debris that floats downstream (embolus).
Blocked blood vesselsFatty plaque formation in the blood vessel wall is called atherosclerosis or "hardening of the arteries." Plaque can rupture and cause a small blood clot to form and occlude the blood vessel. Blockage can also occur when debris from narrowing of a carotid artery breaks off, and floats downstream to cause the occlusion. Sometimes, in people with an irregular heart beat called atrial fibrillation, small blood clots can be formed within the heart and travel to the brain to cause the obstruction.
Picture of Carotid Artery Disease and Plaque Buildup


  Picture of Carotid Artery Disease and Plaque Buildup
Brain hemorrhage or bleeding in the brain can be due to an aneurysm, a weak spot in a blood vessel that ruptures and spills blood into the brain tissue, or it may be due to spontaneous bleeding caused by poorly controlled hypertension (high blood pressure). Such bleeding more commonly results in the irreversible damage of a stroke, as opposed to a TIA.

What are the risk factors for transient ischemic attack (TIA)?

The risk factors for TIA or stroke are the same as those for other vascular disease, similar to heart attack (coronary artery disease) or peripheral vascular disease, which causes decreased blood flow to the legs. These risk factors include:
  • family history
  • smoking,
  • high blood pressure,
  • high cholesterol, and
  • diabetes.
Moreover, any condition that results in stagnant blood flow and or clotting may result in a TIA due to embolization of a blood clot. Such conditions may include atrial fibrillation, large heart attacks, and severe weakness of the heart muscle.

What are the symptoms of transient ischemic attack (TIA)?

The intensity and location of the blood limitation to the brain will determine what symptoms will occur as a result of a stroke or TIA. Many people experience confusion, weakness, and lethargy. If the loss of blood supply is in an area supplied by the middle cerebral artery, a classic sign may include weakness or paralysis and numbness of one side of the body. The whole side may be affected, or just one limb. Often there is a facial droop. If the stroke is on the left side of the body where the speech centers are usually  located, there may be difficulty understanding words or speaking. Partial vision loss may also be part of the constellation of symptoms.
Strokes involving the vertebral arteries decrease blood supply to the base of the brain and may cause a drop attack (a sudden fall while walking or standing, and then a quick recovery), an unexpected collapse, incoordination, or difficulty walking.
The important distinction between stroke and TIA is resolution of the symptoms. By definition, the symptoms of a TIA must completely resolve. And, while this most often occurs within the first few minutes after symptom onset, it may take up to 24 hours to have complete return to normal function.
A special type of TIA is amaurosis fugax. Transient blindness in one eye occurs because debris from a narrowed carotid artery clogs the artery (ophthalmic artery) that supplies blood to the back of the eye.

How is transient ischemic attack (TIA) diagnosed?

TIA is diagnosed by history and physical examination. Since most often the symptoms have resolved, the physician will need to complete a thorough history from the patient and family or friends who witnessed the event. The physical exam will include careful attention to the neurologic examination. This may include:

  • Assess mental status to make certain the patient is alert and oriented.
  • Check eye range of motion and facial movement to evaluate the cranial nerves (the short nerves that run from the brain to the face and neck).
  • Listen to the neck with a stethoscope to detect abnormal sounds that may signal narrowing of the blood vessel (carotid bruits).
  • Check for a regular heart rhythm to rule out the presence of atrial fibrillation.
  • Examine the arms and legs for tone, power, and sensation.
  • Check coordination and balance.
If the diagnosis of TIA is made, further urgent testing is usually recommended, including:

  • Electrocardiogram (EKG) to confirm a regular heart rate
  • Computerized tomography (CT scan) of the brain to assess bleeding
  • Carotid ultrasound to assess for narrowing of the large blood vessels in the neck
  • Some hospitals have CT angiogram available to evaluate the cerebral, carotid, and vertebral arteries. This test is the same as a CT of the head with the addition of intravenous dye into the blood vessels to the arteries.
  • Routine blood tests may include a complete blood count (CBC) to assess for anemia or low red blood cell count or too few platelets (thrombocytopenia). If the patient takes warfarin (Coumadin), a blood thinner, then an international normalized ratio (INR - a blood test that measures the degree of blood thinning) or prothrombin time (PT), may be performed to assess blood clotting measurements.
  • If there is concern that the heart is the source of blood clot or debris, then an echocardiogram or sound wave tracing of the heart may be considered.

Friday 2 September 2011

Sleep Disorders: Hypersomnia

Introduction to Hypersomnia

Hypersomnia, or excessive sleepiness, is a condition in which a person has trouble staying awake during the day. People who have hypersomnia can fall asleep at any time; for instance, at work or while they are driving. They may also have other sleep-related problems, including a lack of energy and trouble thinking clearly.
According to the National Sleep Foundation, up to 40% of people have some symptoms of hypersomnia from time to time.

What Causes Hypersomnia?

There are several potential causes of hypersomnia, including:
  • The sleep disorders narcolepsy (daytime sleepiness) and sleep apnea (interruptions of breathing during sleep)
  • Not getting enough sleep at night (sleep deprivation)
  • Being overweight
  • Drug or alcohol abuse
  • A head injury or a neurological disease, such as multiple sclerosis
  • Prescription drugs, such as tranquilizers
  • Genetics (having a relative with hypersomnia)

How Is Hypersomnia Diagnosed?

If you consistently feel drowsy during the day, talk to your doctor. In making a diagnosis of hypersomnia, your doctor will ask you about your sleeping habits, how much sleep you get at night, if you wake up at night, and whether you fall asleep during the day. Your doctor will also want to know if you are having any emotional problems or are taking any medications that may be interfering with your sleep.
Your doctor may also order some tests, including blood tests, computed tomography (CT) scans, and a sleep test called polysomnography. In some cases, an additional electroencephalogram (EEG), which measures the electrical activity of the brain, is needed.

How Is Hypersomnia Treated?

If you are diagnosed with hypersomnia, your doctor can prescribe various drugs to treat it, including stimulants, antidepressants, as well as several newer medications (for example, Provigil and Xyrem).
If you are diagnosed with sleep apnea, your doctor may prescribe a treatment known as continuous positive airway pressure, or CPAP. With CPAP, you wear a mask over your nose while you are sleeping. A machine that delivers a continuous flow of air into the nostrils is hooked up to the mask. The pressure from air flowing into the nostrils helps keep the airways open.
If you are taking a medication that causes drowsiness, ask your doctor about changing the medication to one that is less likely to make you sleepy. You may also want to go to bed earlier to try to get more sleep at night, and eliminate alcohol and caffeine
.

Bedwetting (Nocturnal Enuresis)

What is bedwetting?

Bedwetting, also called nocturnal enuresis, is the involuntary passage of urine (urinary incontinence) while asleep. Inherent in the definition of bedwetting is satisfactory bladder control while the person is awake. Therefore, urination while awake is a different condition and has a variety of difference causes than bedwetting.

What are the types of bedwetting?

There are two types of bedwetting:
  1. Primary enuresis: bedwetting since infancy
  2. Secondary enuresis: wetting developed after being continually dry for a minimum of six months

What is primary bedwetting?

Primary bedwetting is viewed as a delay in maturation of the nervous system. At 5 years of age, approximately 20% of children wet the bed at least once a month, with about 5% of males and 1% of females wetting nightly. By 6 years of age, only about 10% of children are bedwetters -- the large majority being boys. The percentage of all children who are bedwetters continues to diminish by 50% each year after 5 years of age. Family history plays a big role in predicting primary bedwetting. If one parent was a bedwetter, the offspring have a 45% chance of a developing primary enuresis as well.

What is the basic problem in primary bedwetting?

The fundamental problem for children with primary bedwetting is the inability to recognize messages of the nervous system sent by the full bladder to the sleep arousal centers of the brain while asleep. In addition, bladder capacity is often smaller in bedwetting children than in their peers.

Is primary bedwetting due to emotional problems?

Parents sometimes believe that their child's primary bedwetting is emotional. No medical or scientific literature exists to support this impression.

How is primary bedwetting treated?

The "cure" for primary bedwetting is "tincture (or passage) of time." However, since many parents and children are frustrated with bedwetting as it starts to interfere with self-esteem or social events (for example, sleepovers), a patient step-by-step approach is best. Fortunately, it can be anticipated to have a successful outcome in over 75% of such patients. You should always discuss treatment options with your child's physician, since it is important to differentiate between primary and secondary enuresis prior to starting specific treatments.
It is also important to remember that different children develop differently and that primary enuresis can be a normal developmental stage. Toilet training a child requires special patience. While most children are fully toilet trained by 3-4 years of age, many will not stay dry overnight, even though they can during the day. Reassurance and encouragement often will work in time, but for some children, there are steps that can be taken to address the issues.
Some common recommended management and treatment options include the following:
    1. Encourage voiding prior to bedtime, and restrict fluid intake before bed. 2. Cover the mattress with plastic. 3. Bedwetting alarms: There are generally reserved for older school-age children. There are commercial alarms that are available at most pharmacies. When the device senses urine, it alarms and wakes up the child so he/she can use the toilet. The cure rate is variable. 4. Bladder-stretching exercises are aimed at increasing the bladder volume and increasing the periods between daytime urinations. 5. Medications, such as DDAVP (desmopressin acetate or antidiuretic hormone) and Tofrinil (imipramine), have been shown to be very effective and are used to temporarily treat the nighttime urination, but they do not "cure" the enuresis. Many pediatricians will prescribe one of these medications, especially if the child is engaged in behavioral conditioning as well. Medications are very helpful when a child is not sleeping at home (camp or sleepovers), since the trauma of bedwetting in those settings is predictable. In addition, a recent study presented at the 2009 Pediatric Academic Society's annual meeting suggested that ibuprofen (Motrin, Advil, etc.) may also decrease the incidence of bedwetting by possibly stabilizing the bladder muscle that contracts during urination (detrusor muscle). 

How common is secondary bedwetting?

Only approximately 2%-3% of all children with bedwetting have a medical cause for the condition.

What causes secondary bedwetting?

Urinary tract infections, metabolic disorders (such as diabetes), external pressure on the bladder (such as from a rectal stool mass), and spinal cord disorders are among the causes of secondary bedwetting.

How is the cause of secondary bedwetting diagnosed?

A complete history and thorough physical examination are central to the initial evaluation of a child with primary bedwetting. A urinalysis and urine culture generally complete the workup. Further laboratory and radiological studies are for the child with secondary bedwetting.

What is the treatment for secondary bedwetting?

Therapy of secondary bedwetting is directed at the primary problem causing the symptom of wetting the bed. As expected, cure rates vary depending on the cause of the loss of control.

What is the outlook (prognosis) for children with bedwetting?

In the medical world of today, both primary and secondary bedwetting can be a manageable condition. Treatment programs can successfully eliminate both parental and patient anxiety, frustration, and embarrassment.
Resources for parents
http://www.aap.org
http://www.aafp.org
Bedwetting At A Glance
  • Bedwetting is also called nocturnal enuresis.
  • There are two types of bedwetting: primary and secondary.
  • Primary bedwetting is bedwetting since infancy.
  • Primary bedwetting is due to a delay in the maturing of the nervous system.
  • Primary bedwetting is an inability to recognize messages sent by the bladder to the sleeping brain.
  • The "cure" for primary bedwetting is "tincture (or passage) of time."
  • There are a number of interventions including medical and behavioral options.
  • Secondary bedwetting is wetting after being dry for at least six months.
  • Secondary bedwetting is due to urine infections, diabetes, and other medical conditions.
  • All bedwetting is manageable.
  • Always speak to your child's physician for guidance.