Erythema chronicum migrans is a distinctive rash seen in many patients during the early stages of Lyme disease, immediately after the initial infection. The rash consists of a red, partially raised area with central clearing radiating out from the location of the bite. This rash is a vital diagnostic sign for doctors diagnosing their patients, although it is important to remember that it does not appear in all cases of Lyme disease. People in areas where this tick-borne illness is common should see a doctor if they develop a rash that looks like erythema chronicum migrans.
This rash can develop in hours or days after a bite, depending on the case. It starts with a small, raised, red bump where the tick bit the patient. A whitish area can surround this bump, and it is ringed with redness. Part of the reddened area may be raised in some patients. Also known as a bulls-eye rash because of its distinctive visual appearance, this rash can show up anywhere on the body.
One problem with the erythema chronicum migrans rash is that because people expect to see a round rash in cases of Lyme disease, they may not recognize it for what it is when it appears. In some patients, the rash looks more like a band than a ring, or the rash can be partially hidden by body hair. Ticks sometimes bite at the scalp, and the rash will not be visible if the patient has hair, and the groin is another common location for bites, and the rash may be obscured by pubic hair.
Along with an erythema chronicum migrans rash, a patient can also develop other symptoms. Nausea, vomiting, and diarrhea are sometimes observed along with headache and fatigue. The rash fades with time and the patient can start to develop joint problems, susceptibility to infection, extreme fatigue, and a host of other symptoms. If the rash was not spotted at the time it appeared, a doctor may struggle to diagnose a patient with Lyme symptoms, unless the patient is seeking treatment in an area where the disease is common or with a physician who has seen numerous Lyme patients.
Treatments for Lyme are available, including treatments to manage the symptoms. Antibiotics given at the time the erythema chronicum migrans rash appears can prevent the spread of the causative bacteria, preventing the onset of symptoms later. Patients with chronic infections can be treated with a variety of medications, depending on the symptoms they experience. Doctors who treat Lyme patients use many different approaches, relying on their experience with the disease, as well as the latest published information to make the best treatment decisions for their patients.