Laboratory Tests

Laboratory tests check a sample of your blood, urine, or body tissues. A technician or your doctor analyzes the test samples to see if your results fall within the normal range. The tests use a range because what is normal differs from person to person. Many factors affect test results. These include:

• Your sex, age and race
• What you eat and drink
• Medicines you take
• How well you followed pre-test instructions

Your doctor may also compare your results to results from previous tests. Laboratory tests are often part of a routine checkup to look for changes in your health. They also help doctors diagnose medical conditions, plan or evaluate treatments, and monitor diseases.

Low Blood Pressure

You've probably heard that high blood pressure is a problem. Sometimes blood pressure that is too low can also cause problems.

Blood pressure is the force of your blood pushing against the walls of your arteries. Each time your heart beats, it pumps out blood into the arteries. Your blood pressure is highest when your heart beats, pumping the blood. This is called systolic pressure. When your heart is at rest, between beats, your blood pressure falls. This is the diastolic pressure. Your blood pressure reading uses these two numbers. Usually they're written one above or before the other, such as 120/80. If your blood pressure reading is 90/60 or lower, you have low blood pressure.

Some people have low blood pressure all the time. They have no symptoms and their low readings are normal for them. In other people, blood pressure drops below normal because of a medical condition or certain medicines. Some people may have symptoms of low blood pressure when standing up too quickly. Low blood pressure is a problem only if it causes dizziness, fainting or in extreme cases, shock.

NIH: National Heart, Lung, and Blood Institute

Lyme Disease

What is Lyme disease?

Lyme disease is a bacterial infection you get from the bite of an infected tick. At first, Lyme disease usually causes symptoms such as a rash, fever, headache, and fatigue. But if it is not treated early, the infection can spread to your joints, heart, and nervous system. Prompt treatment can help you recover quickly.

Lyme disease is caused by bacteria. In the United States, this is usually a bacterium called Borrelia burgdorferi. It spreads to humans through the bite of an infected tick. The ticks that spread it are blacklegged ticks (or deer ticks). They are usually found in the:

• Northeast
• Mid-Atlantic
• Upper Midwest
• Pacific coast, especially northern California

These ticks can attach to any part of your body. But they are often found in hard-to-see areas such as your groin, armpits, and scalp. Usually, the tick must be attached to you for more than 24 hours to spread the bacterium to you.

Most tick bites happen in the warmer months (April-September), when ticks are most active and people spend more time outdoors. But you can also get bitten during the rest of the year, especially if the temperatures are warmer than usual.

Most tick bites happen in the summer months when ticks are most active and people spend more time outdoors. But you can get bitten in the warmer months of early fall, or even late winter if temperatures are unusually high. And if there is a mild winter, ticks may come out earlier than usual.

Early symptoms of Lyme disease start between 3 to 30 days after an infected tick bites you. The symptoms can include:

• A red rash called erythema migrans (EM). Most people with Lyme disease get this rash. It gets bigger over several days and may feel warm. It is usually not painful or itchy. As it starts to get better, parts of it may fade. Sometimes this makes the rash look like a "bull's-eye."
• Fever
• Chills
• Headache
• Fatigue
• Muscle and joint aches
• Swollen lymph nodes ("swollen glands")

If the infection is not treated, it can spread to your joints, heart, and nervous system. The symptoms may include:

• Severe headaches and neck stiffness.
• More EM rashes on other areas of your body.
• Facial palsy, which is a weakness in your facial muscles. It can cause drooping on one or both sides of your face.
• Arthritis with severe joint pain and swelling, especially in your knees and other large joints.
• Pain that comes and goes in your tendons, muscles, joints, and bones.
• Heart palpitations, which are feelings that your heart is skipping a beat, fluttering, pounding, or beating too hard or too fast.
• An irregular heart beat (Lyme carditis).
• Episodes of dizziness or shortness of breath.
• Inflammation of the brain and spinal cord.
• Nerve pain.
• Shooting pains, numbness, or tingling in the hands or feet.

To make a diagnosis, your health care provider will consider:

• Your symptoms
• How likely it is that you were exposed to infected blacklegged ticks
• How likely it is that you could have other illnesses that cause similar symptoms
• The results of any lab tests

Most Lyme disease tests check for antibodies made by the body in response to infection. These antibodies can take several weeks to develop. If you are tested right away, it may not show that you have Lyme disease, even if you have it. So you may need to have another test later.

Lyme disease is treated with antibiotics. The earlier you are treated, the better; it gives you the best chance of fully recovering quickly.

After treatment, some patients may still have pain, fatigue, or difficulty thinking that lasts more than 6 months. This is called post-treatment Lyme disease syndrome (PTLDS). Researchers don't know why some people have PTLDS. There is no proven treatment for PTLDS; long-term antibiotics have not been shown to help. However, there are ways to help with the symptoms of PTLDS. If you have been treated for Lyme disease and still feel unwell, contact your health care provider about how to manage your symptoms. Most people do get better with time. But it can take several months before you feel better.

To prevent Lyme disease, you should lower your risk of getting a tick bite:

• Avoid areas where ticks live, such as grassy, brushy, or wooded areas. If you are hiking, walk in the center of the trail to avoid brush and grass.
• Use an Environmental Protection Agency (EPA)-registered insect repellent when you go outdoors. They are evaluated to make sure they are safe and effective. Make sure that the repellant has one of these ingredients: DEET, picaridin, IR3535, oil of lemon eucalyptus, or para-menthane-diol. It is important to follow the instructions on the label.
• Treat your clothing and gear with a repellant containing 0.5% permethrin
• Wear light-colored protective clothing, so you can easily see any ticks that get on you
• Wear a long-sleeved shirt and long pants. Also tuck your shirt into your pants and your pant legs into your socks.
• Check yourself, your children, and your pets daily for ticks. Carefully remove any ticks you find.
• Take a shower and wash and dry your clothes at high temperatures after being outdoors

Centers for Disease Control and Prevention

Meniere's Disease

Meniere's disease is a disorder of the inner ear. It can cause severe dizziness, a roaring sound in your ears called tinnitus, hearing loss that comes and goes and the feeling of ear pressure or pain. It usually affects just one ear. It is a common cause of hearing loss.

Attacks of dizziness may come on suddenly or after a short period of tinnitus or muffled hearing. Some people have single attacks of dizziness once in a while. Others may have many attacks close together over several days. Some people with Meniere's disease have "drop attacks" during which the dizziness is so bad they lose their balance and fall.

Scientists don't yet know the cause. They think that it has to do with the fluid levels or the mixing of fluids in the canals of your inner ear. Doctors diagnose it based on a physical exam and your symptoms. A hearing test can check to see how it has affected your hearing.

There is no cure. Treatments include medicines to control dizziness, limiting salt in your diet, and taking water pills. A device that fits into the outer ear and delivers air pulses to the middle ear can help. Severe cases may require surgery.

NIH: National Institute on Deafness and Other Communication Disorders

Neck Injuries and Disorders

Any part of your neck - muscles, bones, joints, tendons, ligaments, or nerves - can cause neck problems. Neck pain is very common. Pain may also come from your shoulder, jaw, head, or upper arms.

Muscle strain or tension often causes neck pain. The problem is usually overuse, such as from sitting at a computer for too long. Sometimes you can strain your neck muscles from sleeping in an awkward position or overdoing it during exercise. Falls or accidents, including car accidents, are another common cause of neck pain. Whiplash, a soft tissue injury to the neck, is also called neck sprain or strain.

Treatment depends on the cause, but may include applying ice, taking pain relievers, getting physical therapy or wearing a cervical collar. You rarely need surgery.