erythema
(er‵ĭ-thē'mă 
)
[Gr. erythēma, redness]
Reddening of the skin. Erythema is a common but nonspecific sign of skin irritation, injury, or inflammation. It is caused by dilation of superficial blood vessels in the skin.
erythematic, erythematous,
(er‵ĭ-thĕ-mat'ĭk, er‵ĭ-them'ăt-ŭs)
adj.SEE: illus.
e. ab igne Localized erythema due to exposure to heat. SYN: toasted skin syndrome..
e. annulare A red, ring-shaped rash.
SEE: illus.
ABBR: ECM
Erythema migrans.e. dyschromicum perstans Erythema characterized by symmetrical, generalized lesions usually occurring before the age of 40 and an ashen appearance. SYN: ashy dermatosis.
e. elevatum diutinum Erythema affecting the skin on the extensor surfaces of the forearms or legs. It is often seen in those infected with HIV.
e. induratum Chronic erythema occurring in young women. Hard cutaneous nodules break down to form necrotic ulcers and leave atrophic scars. SYN: Bazin disease.
e. infectiosum A mild, moderately contagious erythema seen mostly in school-age children. SYN: fifth disease.
The causative agent is human parvovirus B-19. Transmission is thought to be via respiratory secretions from infected patients; however, maternal-fetal transmission can occur and hemolytic disease of the newborn may result.
Patients experience a mild, brief illness; complaints include fever, malaise, headache, and pruritus. The characteristic erythema appears about 10 days later. Facial redness is similar to that which occurs when a child is slapped; however, circumoral redness is absent. Several days following initial erythema, a less distinct rash may appear on the extremities and trunk. The rash usually resolves within 1 week but may occur for several weeks when the patient is exposed to heat, cold, exercise, or stress. Adults may also experience arthralgia and arthritis although these symptoms are less common in children. In addition, mild transient anemia, thrombocytopenia, and leukopenia may develop.
Most patients require no specific therapy. Patients with chronic hemolytic anemia may experience transient aplastic crisis (TAC). These patients should be warned of the danger of exposure to parvovirus B-19 infection, informed of the early signs and symptoms, and instructed to seek medical consultation promptly if exposure is suspected. Patients with TAC may develop a life-threatening anemia that requires immediate blood transfusion or partial exchange transfusion.
linear gingival e.A band of erythema on the periodontium, appearing as a reddish gingival band about 2 to 3 mm in width. It is often associated with HIV/AIDS.SYN: red band .
e. marginatum Erythema multiforme in which the center of the area fades, leaving elevated edges.
ABBR: EM
An erythema that is hallmark of acute infection with Lyme disease. EM is an expand ing red rash with a sharply defined border and (typically) central clearing. The rash usually appears within 3 to 32 days after a tick bite. The center of the rash is the site of inoculation. The causative agent is Borrelia burgdorferi, a spirochete that may later invade the joints, the central nervous system, or the conducting system of the heart. SYN: chronicum migrans.SEE: Lyme disease for illus.
ABBR: EM
Erythema usually caused by an immune response to drugs or to an infection, esp. herpes simplex virus. It may express itself on the skin in several ways, including macules, papules, blisters, hives, and , characteristically, iris or target lesions. It may affect the palms and soles, the mucous membranes, the face, and the extremities. The disease is usually self-limited. The most severe (and occasionally fatal) variants of the illness, in which the eyes, mouth, and internal organs are involved, are Stevens-Johnson syndrome and toxic epidermal necrolysis.SYN: Hebra disease (1.).SEE: Stevens-Johnson syndrome; toxic epidermal necrolysis.
SEE: illus.
illus.illus.ERYTHEMA MULTIFORME
ABBR: NME
Red, blistering, or crusting patches that appear on the skin of the buttocks, groin, lower extremities, or perineum. The lesions are itchy and painful. NME is often associated with glucagonomas.e. nodosum A tender, red nodular rash on the shins that typically occurs with another illness, such as a streptococcal, fungal, or tubercular infection; inflammatory bowel disease; occult cancer; or sarcoidosis. Biopsies of the rash reveal panniculitis. Because the disease is often associated with other serious illnesses, a diagnostic search for an underlying cause usually is undertaken. In some patients, no cause is identified.
Therapy is directed at the cause, when it is known. Nonsteroidal anti-inflammatory drugs provide symptomatic relief for many patients.
ABBR: ENL
A red, nodular vasculitic rash, which may be a complication of the treatment for leprosy.SEE: lepra.
Treatment consists of withdrawing therapy against leprosy (clofazimine, steroids, thalidomide).
palmar e.Reddening of the palms at the hypothenar and thenar eminences. It is associated with various conditions and diseases, including portal hypertension, chronic liver disease and hepatitis, pregnancy, and polycythemia.
punctate e.Erythema occurring in minute points, such as scarlet fever rash.
toxic e.Erythema or a rash resulting from toxic agents such as drugs.
e. toxicum neonatorum A benign, self-limited erythema marked by firm, yellow-white papules or pustules from 1 to 2 mm in size present in about 50% of full-term infants. The cause is unknown, and the lesions disappear without need for treatment.
e. venenatum Erythema caused by contact with a toxic substance.