Erythema Annulare Centrifugum at a Glance
- Clinical pattern of annular expanding erythematous rings, which enlarge rapidly, fade, and then disappear, as new lesions appear.
- Diagnosis of erythema annulare centrifugum is one of the exclusions.
- Superficial and deep variants can be separated clinically and histologically. Deep form is usually lupus tumidus or erythema migrans.
The figurate erythemas include a variety of eruptions characterized by annular and polycyclic lesions. Classification of this group has always been controversial; the literature abounds with contradictions, uncertainties, and a bewildering array of synonyms. Darier in 1916 was the first to use the term erythema annulare centrifugum1 (EAC), although similar lesions had been described previously under other names. Table 43-1 lists the figurate erythemas and the differential diagnoses to consider.
Table 43-1 Migratory Erythemas |Favorite Table|Download (.pdf)
Table 43-1 Migratory Erythemas
Erythema annulare centrifugum (EAC)
Slowly migrating lesions; often idiopathic.
Erythema gyratum repens
Rapidly moving; usually cancer marker.
Erythema chronicum migrans
Annular lesions originating from tick bite; skin sign of Lyme borreliosis.
Most deep EAC is lupus tumidus. Annular lesions common in neonatal and subacute cutaneous LE; Ro/La antibodies should be sought; overlaps with Sjögren syndrome (especially in Asians).
Giant urticaria is often annular and migratory; patients have ordinary urticaria elsewhere and more pruritus.
Individual lesions closely resemble superficial EAC but pattern and course different
Early lesions often urticarial and may be annular.
Target lesions, usually acral, often mucosal disease; some lesions annular.
Dermatophyte infections and tinea versicolor
Many fungal infections are annular (ringworm); the scale contains hyphae or spores.
Pustular and occasionally ordinary psoriasis may have annular lesions.
Transient, rapidly spreading annular erythema; specific for rheumatic fever.
Necrolytic migratory erythema
Marker for glucagonoma; erosive perioral and acral lesions, but truncal lesions may be polycyclic.
Carrier state chronic granulomatous disease
Female carriers may have annular lupus erythematosus-like rash.
Hereditary lactate dehydrogenase M-subunit deficiency
Rare genodermatosis with annular erythematous and scaly lesions.
Familial annular erythema
Annular erythema of infancy
Many different disorders; must rule out neonatal lupus erythematosus.
EAC is an uncommon disorder. No epidemiologic data are available. There are only three large series in the literature: (1) 66 cases identified clinically,2 (2) 73 first diagnosed histologically,3 and (3) 90 carrying either a clinical or histological diagnosis.4 EAC appears to have no predilection for either sex or for any age group.
Both the annularity and the peripheral spread of EAC have attracted speculation as to a possible mechanism. Most hypotheses have centered on interactions among inflammatory cells, their mediators, and ground substance as foreign antigens diffuse through the skin.5,6
While many possible triggers have been ...