Erythemas Summarized
Erythema ab igne
 • A dermatosis that results from repeated exposure to heat (fires, heating pads, heating blankets, sometimes laptops).
Erythema annulare centrifugum
 • A chronic skin condition thought to be a form of delayed-type hypersensitivity.
 • Can be induced by a variety of potential inciting causes: infections (cutaneous or systemic), malignancies, autoimmune conditions, medications, foods, stress, etc.
Erythema arthriticum epidemicum
 • Condition known as rat bite fever or Haverhill fever caused by the organism Streptobacillus moniliformis. Rash is usually morbilliform and on the extremities
Erythema chronicum migrans
 • Rash of Lyme in early localized disease.
 • Many have moved away from including the word "chronicum" because nothing chronic about it!
Erythema dyschromicum perstans
 • A form of acquired dermal macular hyperpigmentation. It is classified as a variant of lichen planus. Well-circumscribed roundish-oval patches on the face, neck, or trunk most commonly. 
 • No well-described associations.
Erythema elevatum diutinum
 • A rare form of necrotizing vasculitis. Usually composed of papules + nodules on the back of hands, extensor surfaces, and buttocks. 
 • Can be associated with a variety of infections + hematological and rheumatological conditions
Erythema gyratum repens
 • A skin condition presenting with erythematous concentric rings that appear to have a "wood-grain" appearance. 
 • Most commonly associated with cancers, including lung, esophageal, breast, and stomach. Has more rarely been associated with mycobacterial infection and autoimmune conditions.
Erythema induratum
 • A chronic skin condition, usually on the extremities, of painful, indurated nodules associated with tuberculosis.
 • This one is also called "Bazin's disease."
Erythema infectiosum
 • Fever + facial rash that occurs in children with acute Parvovirus B19 infection (so-called fifth disease).
Erythema marginatum
 • Evanescent rash observed in acute rheumatic fever after group A Strep pharyngitis.
Erythema multiforme
 • Acute systemic rash resulting in classic targetoid lesions.
 • Causes are multiple and include: infections (HSV + Mycoplasma classic), autoimmune conditions, malignancies, idiopathic, and medications
Erythema nodosum
 • Tender, reddish-purple nodules classically on the lower extremities.
 • Associated with variety of causes: sarcoidosis (and other autoimmune conditions), infections (streptococcal, endemic mycoses, TB, and others), malignancies, and drugs
Erythema toxicum neonatorum
 • Pustular eruption that occurs within the first few days of life in newborns. Classic association is that smear of the pustular material shows numerous eosinophils.
 • Cause is unknown.

Prathit Kulkarni, MD @PrathitKulkarni

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