Eosinophilic cellulitis or Wells' syndrome in a 6-year-old child

Wells’ syndrome or eosinophilic cellulitis is a rare, recurrent inflammatory dermatosis. Wells described this syndrome in 1971 as “recurrent granulomatous dermatitis with eosinophilia” [8], and in 1979, Wells and Smith proposed the term ‘eosinophilic cellulitis’ [9]. The clinical presentation can be variable, but the histopathologic features are characteristic. The etiology is unknown. Most cases occur in adults, and only a few cases have been reported in children. We present a case of eosinophilic cellulitis on both feet in a 6-year-old boy. Two weeks prior to the eruption he had a high fever and complained of pain in his legs. The fever resolved after 5 days, but toe walking was observed. One week thereafter he developed itchy, painful plaques on the back of his feet, starting at the toes and progressing in a few days to above the ankles. Edema and small blisters developed rapidly. His past medical history included cow’s milk allergy and reactive airway disease. There was no history of recent vaccination. The differential diagnosis included cellulitis, erythema nodosum, glove and sock syndrome (parvovirus B19 infection), first dermal presentation of inflammatory arthritis or inflammatory bowel disease, febrile neutrophilic dermatosis, hypereosinophilic syndrome and lymphoproliferative disease. Rest and ibuprofen were prescribed. During the first 2 days, the lesions became more demarcated, indurated and violaceous at their borders, then slow regression began. A complete blood count showed leukocytosis (21.5×10 cells/l) with eosinophilia (4.19×10 cells/l); hemoglobin and platelet count were normal. The erythrocyte’s sedimentation rate was slightly elevated (38 mm/h). Other laboratory investigations included antibody levels (Mycoplasma, Borrelia, Parvovirus B-19, Bartonella henselae, Yersinia), PCR Parvovirus B-19 and detailed immunologic testing, all of which were normal. Stool culture was negative. Ultrasound examination of the ankles revealed subcutaneous swelling, but no signs of arthritis. The diagnosis of eosinophilic cellulitis was established after a skin biopsy was performed. The epidermis was unremarkable. Extending through the full dermal thickness and hypoderm was a dense mixed inflammatory infiltrate that consisted mostly of eosinophils, neutrophils, lymphocytes and histiocytes. Flame figures (Fig. 1) and foci of degenerated, necrotic collagen fibers were diffusely scattered. No signs of vasculitis, granulomas or parasites were noted. Two weeks after discharge there was complete recovery of the skin. After 6 months, there was a short, less severe relapse with edema and erythema on both feet. Diagnosis of Wells’ syndrome is made by the clinical appearance, course and characteristic histopathologic findings. Lesions can begin with itching or tender burning sensations, subsequent cellulitis-like eruption, well-demarcated nodules or plaques and the development of vesicles or bullae. The lesions progress rapidly over 2–3 days and resolve gradually over 2–8 weeks. They pass through a blue-greyish discoloration phase to form atrophic plaques, sometimes with hyperpigmentation, and they heal generS. Van der Straaten . M. Wojciechowski (*) . M. Hagendorens Department of Pediatrics, University Hospital Antwerp, Wilrijkstraat 10, 2650 Edegem, Belgium e-mail: Marek.Wojciechowski@uza.be Tel.: +32-38-213810 Fax: +32-38-291194