BRIEF ARTICLE Eosinophilic Annular Erythema of Childhood: A Rare Case

Eosinophilic annular erythema (EAE) of childhood is a rare and recurrent skin condition, with only a few cases described in the literature. The etiology of EAE in children remains unclear. Clinical presentation shows a persistent, non-pruritic, urticarial annular lesions that enlarge in a centrifugal pattern. Biopsy is required for diagnosis which characteristically shows a perivascular eosinophilic infiltrate concentrated in the dermis. Although there is considerable overlap between EAE and Annular Erythema of Infancy (AEI), some proposed differences include age of onset, duration of lesions, presence of mucin deposition of histopathology, and time to resolution. This case report describes a rare case of EAE of childhood in a newborn with associated neonatal eosinophilic pustulosis and laboratory abnormalities.

Eosinophilic annular erythema (EAE) of childhood is a rare and recurrent skin condition, with few cases described in the literature. The trunk and proximal extremities are mostly commonly affected. 1-3 EAE of childhood is characterized by the appearance of persistent, non-pruritic, urticarial annular lesions that enlarge in a centrifugal pattern. 1,2,4,5 Histopathology is often required for diagnosis, with lesions exhibiting a perivascular eosinophilic infiltrate concentrated in the dermis. [1][2][3] This case report describes a rare case of EAE of childhood in a newborn with associated neonatal eosinophilic pustulosis and laboratory abnormalities.
The patient is a three-week-old male who was seen in the hospital for a generalized eruption distributed on the trunk and extremities, which developed four days following birth. The lesions were initially described as bright red targetoid plaques. After a few days, the lesions improved for a short period before recurring. Due to worsening of the rash along with concomitant diarrhea with streaks of blood and concerns for dehydration, the patient was admitted for further work-up and supportive care. Upon dermatologic exam, the patient had generalized annular erythematous plaques with elevated borders and without scaling (Figure 1-2). The mother stated the lesions come and go and change

INTRODUCTION CASE REPORT
in shape and distribution. In addition to the lesions on the trunk and extremities, multiple pustules over an eczematous base appeared on the bilateral cheeks and forehead. No lesions were noted on volar or mucosal surfaces. Per the mother, the patient did not appear irritable. The pregnancy was full term without history of autoimmune disease. The patient's vitals remained stable throughout the hospital course. Laboratory work-up showed consistent hypereosinophilia, peaking at 7,560 µl (36%) and elevated total immunoglobulin E (IgE). Subsequent allergic, immunologic, hematologic, gastrointestinal, and cardiac work-up was unremarkable.
The clinical differential for the lesions on the trunk and extremities included eosinophilic dermatosis, EAE of childhood, annular erythema of infancy (AEI), neonatal eosinophilic pustulosis, erythema annularis centrifugum (EAC), and neonatal lupus. A 3-0 punch biopsy was performed on the right lower extremity. Histology showed mild spongiosis without parakeratosis and eosinophils interstitially and perivascularly in the dermis (Figure 3a-c). PAS stain was negative for fungi. There was no evidence of vasculitis or other significant inflammatory infiltrate.
The histological differential included hypersensitivity reaction and allergic reaction.  EAE has also been described as an annular variant of Well's Syndrome (WS), or eosinophilic cellulitis. WS, however, is thought to be histopathologically characterized by a diffuse inflammatory infiltrate rather than perivascular inflammatory infiltrate, eosinophilic degranulation, the presence of flame figures (deposits of major basic protein and degenerated collagen) with surrounding granulomatous reaction, and vasculitis. 1,2,4,5 Additionally, resolution of WS lesions is associated with hyperpigmentation and/or residual atrophy, which is not typical for EAE. 1 Neonatal lupus may also be included in the differential diagnosis, as it can present with subacute cutaneous lupus erythematosus-like annular erythematous plaques. 8 However, these lesions are located in sun exposed areas (i.e. the face), have fine scaling, and are often associated with systemic findings such as congenital heart block, hepatobiliary involvement, and cytopenias. Additionally, histopathology would show vacuolar interface changes, which were not seen on biopsy in our DISCUSSION patient. Finally, EAC is another migratory annular erythema that can rarely occur in newborns, but prominent eosinophils are not noted on biopsy. [4][5][6] The etiology of EAE is unclear. It has been previously suggested that EAE may be due to a hypersensitivity reaction, though no antigen has been identified. In children, EAE has been diagnosed in association with asthma, though often no evidence for underlying disease is found. 1 In early documented cases of AEI, associated intestinal candida colonization and oral candidiasis was also reported. 7,9 Laboratory abnormalities can occur, though they are not required for diagnosis. Peripheral eosinophilia has been reported in some cases; 3 however, elevated IgE levels have not been previously reported. Interestingly, patients with neonatal eosinophilic pustolosis frequently present with peripheral eosinophilia. 10 Further, infants with hyperimmunoglobulin E (hyper-IgE) syndrome can present with a crusting pustular eruption on the face and scalp similar to that of neonatal eosinophilic pustulosis, which would be associated with elevated IgE levels and persistent eosinophilia. 11 However, our patient lacked  [1][2][3][4] Recurrence has been noted in several reports. In our patient, topical mid-potency steroids appeared to resolve the lesions.
To our knowledge, this is the earliest reported case of EAE in a newborn and among few cases of EAE reported in the pediatric population. Our case is significant for its association with neonatal eosinophilic pustulosis, peripheral eosinophilia, and elevated IgE. Overall, this report provides new information to the limited knowledge surrounding this rare condition.