Eosinophilic cellulitis (syn. Wells syndrome)

Eosinophilic cellulitis is a very rare condition that was first described in 1971 by George Wells. The presentation usually involves a cellulitis-like eruption, although papular, nodular  and bullous eruptions have been reported. 

This chapter is set out as follows:

• Although the cause is unknown it may be due to drugs, infection, inflammatory bowel disease, and malignancy 

• Itch or a burning sensation are common, often in the early stages 
• Patients are usually systemically well although fever has been reported 

Distribution 

• The rash most commonly occurs on the limbs, but may also affect the trunk. Lesions may be solitary or multiple

Morphology

• Lesions evolve over a few days to become large, erythematous indurated plaques resembling both cellulitis and urticaria. Papules, nodules and bullous lesions can also occur

• Lesions may last for several weeks, and gradually turn grey-brown, sometimes with a green tinge. Complete resolution without scarring is typical, although lesions can recur 

Eosinophilic annular erythema (EAE) is a rare variant of eosinophilic cellulitis. EAE is clinically characterised by recurrent annular, erythematous-oedematous, pruritic lesions with a centrifugal growth pattern. EAE is most common in children but can affect adults. In a few cases, lesions of both EAE and more typical features of eosinophilic cellulitis have been reported.

• A FBC may reveal an eosinophilia 

• A skin biopsy shows a dermal infiltrate of eosinophils, histiocytes, and eosinophil debris between collagen bundles that forms flame figures

• Mild symptoms - most cases are mild and respond to topical steroid therapy 
   
• Moderate-severe symptoms (uncommon) 
  • Systemic steroids can lead to a dramatic improvement within days and the course is typically tapered over one month
  • Other treatments sometimes used include the tetracycline antibiotics (which have an anti-inflammatory role in the skin), dapsone, and ciclosporin