Erythema annulare centrifugum typically begins in middle age and follows a course of 2 or more years.2 It occurs in association with an underlying infection or neoplasm, and it can develop on the trunk and proximal extremities. Morphologically, EAC can present with arcuate or polycyclic lesions with trailing scale. Histologically, a skin biopsy shows a tight, coat sleeve–like, perivascular, lymphohistiocytic infiltrate in the dermis, with variable epidermal spongiosis and parakeratosis.16 Our patient’s biopsy did show a tight perivascular infiltrate, raising suspicion for EAC. However, the eruption occurred in infancy, and she had no clinical evidence of infection or neoplasm.
Familial annular erythemas can arise within a few days after birth and can present on any part of the body, including the tongue.2 Individual lesions can persist for 4 to 5 days and can accompany congenital malformations. Morphologically, they can present as papules that slowly enlarge to form arcuate lesions with central hyperpigmentation. Histologically, there can be a mild, perivascular, lymphocytic infiltrate in the dermis.16 Our patient’s lesions showed no scale or pigmentation and occurred without a family history or associated malformations.
Erythema gyratum atrophicans transiens neonatale also can arise in the first few days of life and can affect the trunk, neck, and lips.16 Morphologically, the skin lesions can present as arcuate erythematous patches (3–20 mm) with raised borders and central atrophy. Histologically, there is epidermal atrophy with a dermal perivascular mononuclear cell infiltrate with edema. Our patient’s clinical presentation was not classic for this condition, and the lesions showed no atrophy.
Erythema chronicum migrans can arise in children, often with a history of an arthropod bite.13 Morphologically, lesions can evolve over weeks to months and rarely are multiple. Erythema chronicum migrans most commonly occurs in the United States in association with Lyme disease from infection with Borrelia burgdorferi. Histologically, erythema chronicum migrans shows a superficial and deep, perivascular lymphocytic infiltrate in the dermis with plasma cells and eosinophils. A silver stain can demonstrate dermal spirochetes. Our patient had no history of an arthropod bite. A Warthin-Starry stain performed on the biopsy was negative for spirochetes, and serologies for Lyme disease were negative.
Urticaria is rare in neonates and can occur on any part of the body.2 Morphologically, the skin lesions can present as arcuate, erythematous, and polycyclic plaques that wax and wane. Histologically, there is dermal edema with a mild, perivascular and interstitial, mixed inflammatory infiltrate.16 Our patient’s biopsy did not reveal notable edema, and the perivascular infiltrate was coat sleeve–like with few neutrophils and eosinophils. The patient did not respond to initial treatment with antihistamines, making urticaria less likely.