Acute Hemorrhagic Edema of Infancy: A Rare Cause of Bilateral Ear Erythema

Acute hemorrhagic edema of infancy (AHEI) is a rare cutaneous leukocytoclastic small-vessel vasculitis presenting with purpuric skin plaques on the face, ears, and extremities, frequently associated with fever and edema. Although the condition usually self-resolves over one to three weeks, it can be mistaken for more serious conditions, leading to unnecessary procedures and treatments. This case involves a nine-month-old infant who developed bilateral ear erythema and edema two days after a viral illness and was hospitalized for clinical suspicion of relapsing polychondritis. Within a couple of hours, the infant's erythema and edema progressed, with the appearance of small papules scattered across the right half of the face. Over five days, the patient developed purpuric lesions on the cheeks, chin, bilateral extremities, and trunk. During the hospitalization, the infant received empiric antibiotics, steroids, and antihistamines. Based on the acute edema, scattered purpuric lesions in the setting of a recent viral illness, and negative infectious workup, the infant was diagnosed with AHEI and subsequently managed with steroids to reduce the inflammation rapidly and antihistamines to reduce corticosteroid-induced gastric complications. The ear erythema, ear edema, and purpuric lesions showed resolution 10 days after initial presentation at the outpatient pediatric follow-up. However, while the infant was in good health overall at the outpatient dermatology follow-up approximately three weeks after hospitalization, he did have residual macular spots on the cheeks and bilateral lower extremities. The macular spots disappeared, and the infant had no cutaneous lesions two months after the initial presentation. The resolution of symptoms after oral steroids confirmed the clinical diagnosis of AHEI rather than relapsing polychondritis. This case serves to illustrate an unusual presentation of AHEI to aid in the future diagnosis of infantile rashes and to differentiate this benign diagnosis from other, life-threatening conditions. Early recognition of AHEI could prevent unnecessary treatments or procedures in the future.