Is this rash a dermatologic emergency?

Case: A 16-month-old girl has had a worsening rash, decreased oral intake, and irritability for the past 2 days. Before the rash appeared, she had been hospitalized for 4 days for presumed bronchiolitis and acute otitis media and discharged with oral amoxicillin. Two days later, she was brought to another emergency department, where an intraosseous line was placed because of generalized edema and tachycardia, followed by transfer to our facility.

On examination, the child is afebrile, with a heart rate of 198 beats per minute, respiration rate of 47 breaths per minute, and normal blood pressure. She has diffuse, purpuric, targetoid patches over the thighs, chest, back, and arms. Erythematous patches and plaques surround the eyes and extend around the perioral region onto the chin. A friable white film is noted on the tongue and within the buccal mucosa that is easily removed with a tongue depressor. The child has diffuse edema of all 4 extremities and both ears.

Is the rash and edema in this child a dermatologic emergency?

(Answer on next page.)

No, acute hemorrhagic edema of infancy is usually benign and spontaneously resolves without treatment.

Acute hemorrhagic edema of infancy (AHEI) is typically a benign, self-limited leukocytoclastic vasculitis.¹ The incidence is unknown because of the rarity of the disease; however, more than 100 cases have been reported worldwide.² AHEI is often preceded by respiratory tract infection, immunizations, or drug intake (eg, antimicrobial therapy).³

Some hypothesize that AHEI is a variant of Henoch-Schönlein purpura (HSP) because of the similar and often dramatic presentation of the 2 conditions. The differential diagnosis includes but is not limited to HSP, meningococcemia, septicemia, erythema multiforme, Kawasaki disease, and Rocky Mountain spotted fever.

Common laboratory findings include mild leukocytosis and a mildly elevated erythrocyte sedimentation rate. In this patient, laboratory results, including a complete blood cell count, comprehensive metabolic panel, urinalysis, and C3 and C4 levels, were within normal limits.

Suggested diagnostic criteria include:

•Patient age younger than 2 years.

•Purpuric or ecchymotic targetlike lesions with edema of the face, ears, and extremities, with or without mucosal involvement.

•Lack of systemic disease.

•Spontaneous recovery within a few days to weeks.¹

Although there is no specific treatment for AHEI, some case reports suggest that systemic corticosteroids and antihistamines are useful.⁴ These treatments were provided to the child in this case. Her symptoms rapidly resolved, and she was discharged home after 3 days. The majority of cases of AHEI resolve spontaneously within several days, and symptoms rarely recur.⁵ Uncommonly reported complications of AHEI include residual hyperpigmentation or scarring,³ GI bleeding, intussusception,⁶ and nephritis.⁷