What is Lyme disease? What causes Lyme disease?

What is Lyme disease? What causes Lyme disease?

Lyme disease is a bacterial illness caused by a bacterium called a “spirochete.” In the United States, the actual name of the bacterium is Borrelia burgdorferi. In Europe, another bacterium, Borrelia afzelii, also causes Lyme disease. Certain ticks found on deer harbor the bacterium in their stomachs. Lyme disease is spread by these ticks when they bite the skin, which permits the bacterium to infect the body. Lyme disease is not contagious from an affected person to someone else. Lyme disease can cause abnormalities in the skin, joints, heart, and nervous system.

What are symptoms and signs of Lyme disease?

Lyme disease affects different areas of the body in varying degrees as it progresses. The site where the tick bites the body is where the bacteria enter through the skin. As the bacteria spread in the skin away from the initial tick bite, the infection causes an expanding reddish rash that is often associated with “flu-like” symptoms. Later, it can produce abnormalities in the joints, heart, and nervous system.
Lyme disease is medically described in three phases as: (1) early localized disease with skin inflammation; (2) early disseminated disease with heart and nervous system involvement, including palsies and meningitis; and (3) late disease featuring motor and sensory nerve damage and brain inflammation as well as arthritis.
In the early phase of the illness, within days to weeks of the tick bite, the skin around the bite develops an expanding ring of unraised redness. There may be an outer ring of brighter redness and a central area of clearing, leading to a “bull’s-eye” appearance. This classic initial rash is called “erythema migrans” (formerly called erythema chronicum migrans). Patients often can’t recall the tick bite (the ticks can be as small as the periods in this paragraph). Also, they may not have the identifying rash to signal the doctor. More than one in four patients never even develop a rash. The redness of the skin is often accompanied by generalized fatigue, muscle and joint stiffness, swollen lymph nodes (“swollen glands”), and headache, resembling symptoms of a virus infection.
The redness resolves, without treatment, in about a month. Weeks to months after the initial redness of the skin the bacteria and their effects spread throughout the body. Subsequently, disease in the joints, heart, and nervous system can occur.
The later phases of Lyme disease can affect the heart, causing inflammation of the heart muscle. This can result in abnormal heart rhythms and heart failure. The nervous system can develop facial muscle paralysis (Bell’s palsy), abnormal sensation due to disease of peripheral nerves (peripheral neuropathy), meningitis, and confusion. Arthritis, or inflammation in the joints, begins with swelling, stiffness, and pain. Usually, only one or a few joints become affected, most commonly the knees. The arthritis of Lyme disease can look like many other types of inflammatory arthritis and can become chronic.
Researchers have also found that anxiety and depression occur with an increased rate in people with Lyme disease. This is another important aspect of the evaluation and management of this condition.

What is the treatment for Lyme disease, and what is its prognosis?

Most cases of Lyme disease are curable with antibiotics. This is so true that some authors of Lyme disease research have stated that the most common cause of lack of response of Lyme disease to antibiotics is a lack of Lyme disease to begin with! The type of antibiotic depends on the stage of the disease (early or late) and what areas of the body are affected. Early illness is usually treated with medicines taken by mouth, for example, doxycycline (Vibramycin), amoxicillin (Amoxil), or cefuroxime axetil (Ceftin). Of note, doxycycline should not be used in pregnancy or in children under 8 years of age.
Therefore, if a person finds a typical bull’s-eye skin rash (described above) developing in an area of a tick bite, they should seek medical attention as soon as possible. Generally, antibiotic treatment resolves the rash within one or two weeks with no long-term consequences. Later illness such as nervous-system disease might require intravenous drugs; examples are ceftriaxone (Rocephin) and penicillin G.
For the relief of symptoms, pain-relieving medicines might be added. Swollen joints can be reduced by the doctor removing fluid from them (arthrocentesis). An arthrocentesis is a procedure whereby fluid is removed from a joint using a needle and syringe under sterile conditions. It is usually performed in a doctor’s office. Rarely, even with appropriate antibiotics, the arthritis continues. It has been suggested by researchers that sometimes joint inflammation can persist even after eradication of the Lyme bacteria. This has been explained as an ongoing autoimmune response causing inflammation of the joint that was initially stimulated by the original bacterial infection. The doctor also can use oral medications such as ibuprofen (Motrin, Nuprin) to reduce inflammation and improve function.


Know more: http://www.cdc.gov/lyme/