What are Lyme disease symptoms and signs?
Lyme disease affects different areas of the body in varying degrees as it progresses. The site where the tick bites the skin is where the bacteria enter the body through the skin. Days to weeks later, as the bacteria spread in the skin away from the initial tick bite, the tick-borne 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 (stages) as
- early localized disease with skin inflammation and rash;
- early disseminated disease with heart and nervous system involvement, including palsies and meningitis; and
- 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 with or without a central area of clearing, leading to a "bulls-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. The rash may or may not itch. 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 pain and stiffness, swollen lymph nodes ("swollen glands"), headache, and less often fever, resembling symptoms of a viral 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, a disease in the joints, heart, and nervous system can occur.
The later phases of Lyme borreliosis can affect the heart, causing inflammation of the heart muscle. This can result in abnormal heart rhythms and heart failure. The nervous system signs can include facial muscle paralysis (Bell's palsy), an 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. Lyme arthritis can look like many other types of inflammatory arthritis and can become chronic.
Researchers have also found that anxiety and depression occur at an increased rate in people with Lyme disease. This is another important aspect of the evaluation and management of this condition.