Erythema chronicum migrans
Encyclopedia
Erythema chronicum migrans refers to the rash often (though not always) seen in the early stage of Lyme disease
. It can appear anywhere from one day to one month after a tick bite. This rash does not represent an allergic reaction to the bite, but rather an actual skin infection with the Lyme bacteria, Borrelia burgdorferi sensu lato
. "Erythema migrans is the only manifestation of Lyme disease in the United States that is sufficiently distinctive to allow clinical diagnosis in the absence of laboratory confirmation.". It is a pathognomonic
sign: a physician-identified rash warrants an instant diagnosis of Lyme disease and immediate treatment without further testing, even by the strict criteria of the Centers for Disease Control. These rashes are characteristic of Borrelia infections and no other pathogens are known that cause this form of rash.
This erythema
is also sometimes called erythema migrans or EM. However, this phrase is also used to describe geographic tongue
.
first presented research about an expanding, ring-like lesion he had observed. Afzelius published his work 12 years later and speculated the rash came from the bite of an Ixodes
tick
, meningitic
symptoms and signs in a number of cases and that both sexes were affected. This rash is now known as erythema chronicum migrans, the skin rash found in early-stage Lyme disease.
In the 1920s, French physicians Garin and Bujadoux described a patient with meningoencephalitis, painful sensory radiculitis, and erythema migrans following a tick bite, and they postulated the symptoms were due to a spirochetal infection. In the 1940s, German neurologist Alfred Bannwarth
described several cases of chronic lymphocytic meningitis and polyradiculoneuritis, some of which were accompanied by erythematous skin lesions.
(2%). Because of the "bullseye" description to describe the Lyme disease rash, the condition commonly called ringworm is sometimes confused with Lyme disease. Uncommonly, EM may be less than 5 cm in diameter
. Multiple painless EM rashes may occur, indicating disseminated infection.
The EM rash occurs, according to sources, in 80% to 90% of those infected with Borrelia. A systematic review
of the medical literature showed 80% of patients have an expanding EM rash, at the site of the tick bite, although some patients with EM do not recall a tick bite. In endemic areas of the United States, homogeneously red rashes are more frequent.
A significant group of practitioners disputes the generally accepted incidence
of the rash, claiming it occurs in less than 50% of infections. These practitioners suggest a condition they call "chronic Lyme" (resembling chronic fatigue syndrome
or fibromyalgia
) exists in the absence of evidence for Borrelia infection. Their proposed treatment of patients with months or years of antibiotics is opposed by the wider medical community's scientific consensus
, since these treatments are potentially dangerous, are not based on diagnoses with objective evidence, and have been shown in clinical trials to be ineffective even when evidence of infection is present.
when extensive areas in the oral cavity mucosa are affected, or geographic tongue
when confined to the dorsal and lateral aspects of the tongue
mucosa, is a very common entity of unknown etiology
and pathogenesis
that affects 1% to 2.5% of the general population.
Lyme disease
Lyme disease, or Lyme borreliosis, is an emerging infectious disease caused by at least three species of bacteria belonging to the genus Borrelia. Borrelia burgdorferi sensu stricto is the main cause of Lyme disease in the United States, whereas Borrelia afzelii and Borrelia garinii cause most...
. It can appear anywhere from one day to one month after a tick bite. This rash does not represent an allergic reaction to the bite, but rather an actual skin infection with the Lyme bacteria, Borrelia burgdorferi sensu lato
Lyme disease microbiology
Lyme disease, or borreliosis, is caused by Gram negative spirochetal bacteria from the genus Borrelia, which has at least 37 known species, 12 of which are Lyme related, and an unknown number of genomic strains...
. "Erythema migrans is the only manifestation of Lyme disease in the United States that is sufficiently distinctive to allow clinical diagnosis in the absence of laboratory confirmation.". It is a pathognomonic
Pathognomonic
Pathognomonic is a term, often used in medicine, that means characteristic for a particular disease. A pathognomonic sign is a particular sign whose presence means that a particular disease is present beyond any doubt...
sign: a physician-identified rash warrants an instant diagnosis of Lyme disease and immediate treatment without further testing, even by the strict criteria of the Centers for Disease Control. These rashes are characteristic of Borrelia infections and no other pathogens are known that cause this form of rash.
This erythema
Erythema
Erythema is redness of the skin, caused by hyperemia of the capillaries in the lower layers of the skin. It occurs with any skin injury, infection, or inflammation...
is also sometimes called erythema migrans or EM. However, this phrase is also used to describe geographic tongue
Geographic tongue
Geographic tongue, an inflammatory condition of the tongue affecting approximately 2% of the population, is characterized by discolored regions of taste buds or sometimes even cracks in the tongue...
.
History
In a 1909 meeting of the Swedish Society of Dermatology, Arvid AfzeliusArvid Afzelius
Arvid Afzelius was a Swedish dermatologist.As a student at the Karolinska institutet, Afzelius studied under the prominent dermatologist Moritz Kaposi in Vienna...
first presented research about an expanding, ring-like lesion he had observed. Afzelius published his work 12 years later and speculated the rash came from the bite of an Ixodes
Ixodes
Ixodes is a genus of hard-bodied ticks . It includes important disease vectors of animals and humans . Some ticks in this genus may transmit the pathogenic bacterium Borrelia burgdorferi responsible for causing Lyme disease...
tick
Tick
Ticks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...
, meningitic
Meningitis
Meningitis is inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. The inflammation may be caused by infection with viruses, bacteria, or other microorganisms, and less commonly by certain drugs...
symptoms and signs in a number of cases and that both sexes were affected. This rash is now known as erythema chronicum migrans, the skin rash found in early-stage Lyme disease.
In the 1920s, French physicians Garin and Bujadoux described a patient with meningoencephalitis, painful sensory radiculitis, and erythema migrans following a tick bite, and they postulated the symptoms were due to a spirochetal infection. In the 1940s, German neurologist Alfred Bannwarth
Alfred Bannwarth
German neurologist, 1903-1970. Munich. Credited for discovering cases of lymphocytic meningoradiculitis with facial nerve palsies, an early description of neuroborreliosis and called Bannwarth's syndrome in his honor....
described several cases of chronic lymphocytic meningitis and polyradiculoneuritis, some of which were accompanied by erythematous skin lesions.
Description
The erythema migrans rash is classically 5 to 6.8 cm in diameter, appearing as an annular homogenous erythema (59%), central erythema (30%), central clearing (9%), or central purpuraPurpura
Purpura is the appearance of red or purple discolorations on the skin that do not blanch on applying pressure. They are caused by bleeding underneath the skin...
(2%). Because of the "bullseye" description to describe the Lyme disease rash, the condition commonly called ringworm is sometimes confused with Lyme disease. Uncommonly, EM may be less than 5 cm in diameter
Diameter
In geometry, a diameter of a circle is any straight line segment that passes through the center of the circle and whose endpoints are on the circle. The diameters are the longest chords of the circle...
. Multiple painless EM rashes may occur, indicating disseminated infection.
The EM rash occurs, according to sources, in 80% to 90% of those infected with Borrelia. A systematic review
Systematic review
A systematic review is a literature review focused on a research question that tries to identify, appraise, select and synthesize all high quality research evidence relevant to that question. Systematic reviews of high-quality randomized controlled trials are crucial to evidence-based medicine...
of the medical literature showed 80% of patients have an expanding EM rash, at the site of the tick bite, although some patients with EM do not recall a tick bite. In endemic areas of the United States, homogeneously red rashes are more frequent.
A significant group of practitioners disputes the generally accepted incidence
Incidence (epidemiology)
Incidence is a measure of the risk of developing some new condition within a specified period of time. Although sometimes loosely expressed simply as the number of new cases during some time period, it is better expressed as a proportion or a rate with a denominator.Incidence proportion is the...
of the rash, claiming it occurs in less than 50% of infections. These practitioners suggest a condition they call "chronic Lyme" (resembling chronic fatigue syndrome
Chronic fatigue syndrome
Chronic fatigue syndrome is the most common name used to designate a significantly debilitating medical disorder or group of disorders generally defined by persistent fatigue accompanied by other specific symptoms for a minimum of six months, not due to ongoing exertion, not substantially...
or fibromyalgia
Fibromyalgia
Fibromyalgia is a medical disorder characterized by chronic widespread pain and allodynia, a heightened and painful response to pressure. It is an example of a diagnosis of exclusion...
) exists in the absence of evidence for Borrelia infection. Their proposed treatment of patients with months or years of antibiotics is opposed by the wider medical community's scientific consensus
Scientific consensus
Scientific consensus is the collective judgment, position, and opinion of the community of scientists in a particular field of study. Consensus implies general agreement, though not necessarily unanimity. Scientific consensus is not by itself a scientific argument, and it is not part of the...
, since these treatments are potentially dangerous, are not based on diagnoses with objective evidence, and have been shown in clinical trials to be ineffective even when evidence of infection is present.
Oral erythema migrans
Oral erythema migrans also called migratory stomatitisMigratory stomatitis
Migratory stomatitis is a benign condition on the oral soft tissue. This condition has two forms: the common form, which is consisted from red lesions with white borders on the tongue only. This form is called geographic tongue...
when extensive areas in the oral cavity mucosa are affected, or geographic tongue
Geographic tongue
Geographic tongue, an inflammatory condition of the tongue affecting approximately 2% of the population, is characterized by discolored regions of taste buds or sometimes even cracks in the tongue...
when confined to the dorsal and lateral aspects of the tongue
Tongue
The tongue is a muscular hydrostat on the floors of the mouths of most vertebrates which manipulates food for mastication. It is the primary organ of taste , as much of the upper surface of the tongue is covered in papillae and taste buds. It is sensitive and kept moist by saliva, and is richly...
mucosa, is a very common entity of unknown etiology
Etiology
Etiology is the study of causation, or origination. The word is derived from the Greek , aitiologia, "giving a reason for" ....
and pathogenesis
Pathogenesis
The pathogenesis of a disease is the mechanism by which the disease is caused. The term can also be used to describe the origin and development of the disease and whether it is acute, chronic or recurrent...
that affects 1% to 2.5% of the general population.
See also
- Acrodermatitis chronica atrophicansAcrodermatitis chronica atrophicansAcrodermatitis chronica atrophicans is a skin rash indicative of the third or late stage of European Lyme borreliosis....