Wells Syndrome with Sustained Response to Omalizumab

Wells syndrome (eosinophilic cellulitis) is a rare dermatosis characterized by pruritic and erythematous plaques, papules, vesicles, or blisters that commonly appear on the extremities. Autoimmunity, insect bites, drugs, contact allergens, infections, and photosensitivity are triggers that have previously been associated with this diagnosis. Treatment options for Wells syndrome include corticosteroids, antihistamines, antibiotics, immunosuppressants, and biologics. We present a case of Wells syndrome that was unresponsive to corticosteroids, antivirals, antibiotics, antihistamines, and dapsone. This case reflects one of the few reported instances of Wells syndrome that was successfully treated with omalizumab. A 39-year-old female with no significant past medical history presented with a three-year history of small pruritic papules located on the face, extremities, and genitals (Figure 1).


BRIEF ARTICLE Wells Syndrome with Sustained Response to Omalizumab
Kezia Surjanto, BS 1 , Gage Rensch, MD 1 , Garrett Vick, MD 1 , Andrea Murina, MD 1 1 Tulane University School of Medicine, New Orleans, LA Wells syndrome (eosinophilic cellulitis) is a rare dermatosis characterized by pruritic and erythematous plaques, papules, vesicles, or blisters that commonly appear on the extremities. Autoimmunity, insect bites, drugs, contact allergens, infections, and photosensitivity are triggers that have previously been associated with this diagnosis. 1 Treatment options for Wells  syndrome  include  corticosteroids,  antihistamines, antibiotics, immunosuppressants, and biologics. 2 We present a case of Wells syndrome that was unresponsive to corticosteroids, antivirals, antibiotics, antihistamines, and dapsone. This case reflects one of the few reported instances of Wells syndrome that was successfully treated with omalizumab.
A 39-year-old female with no significant past medical history presented with a three-year history of small pruritic papules located on the face, extremities, and genitals ( Figure 1).

INTRODUCTION CASE REPORT
Further review of systems was negative. Prior to initial presentation, she trialed valacyclovir, clobetasol, mupirocin, and loratadine without improvement. Previous labs showed negative ANA and a normal eosinophil count. At the first visit, she was prescribed betamethasone ointment and an increased dose frequency of loratadine from once to twice a day. A scraping for scabies was negative, which prompted a punch biopsy of the left lower arm. Biopsy sections showed a dense infiltrate in the dermis with abundant eosinophils (Figure 2) as well as characteristic "flame figure" formation ( Figure 3) that supported a diagnosis of Wells syndrome.
At follow up, the patient noted progression of her symptoms with a new plaque on the right hip and new pruritic papules arising on a weekly basis. She was started on prednisone 60 mg daily with a month-long taper, daily cetirizine and nightly hydroxyzine. Although her skin cleared with the medications, her symptoms flared once the prednisone dose was tapered to 10 mg. She was then started on dapsone 50 mg daily, which decreased the tenderness of her lesions and the frequency of her flares.
Nine months after taking dapsone, the patient reported decreased grip strength in her right hand, which affected her work as an aesthetician. To avoid worsening of musculoskeletal sequelae, dapsone was discontinued and she was referred to neurology. The patient was then started on omalizumab 150 mg subcutaneously every 28 days.
The patient tolerated the omalizumab injections well, reporting no more than one flare of her skin in between injections and an overall improvement without any reported side effects. This patient has been on omalizumab for over 9 months now with excellent control of her symptoms. Wells syndrome is an uncommon dermatosis believed to be a type IV hypersensitivity reaction. 2,3 Although many variants of Wells syndrome have been observed, characteristics such as pruritic and tender erythematous plaques on gross observation, along with dermal infiltrate of eosinophils with "flame figures" on histology, tend to be suggestive of the diagnosis. 2,3 Said "flame figures" represent aggregates of major basic protein released from eosinophils which disintegrate the structural integrity of surrounding collagen and subsequently destroy local tissue. 1 In addition to characteristic histological features, Wells syndrome criteria that were seen in our patient also include a recurrent course of cutaneous manifestations, no evidence of triggering factors, and inconsistent blood eosinophilia. 4 Previously reported treatments for Wells syndrome are vast, ranging from corticosteroids to biologics. 2 However, there are only a handful of papers that report the use and efficacy of omalizumab. Omalizumab is a monoclonal antiimmunoglobulin E (IgE) antibody that was first approved for the treatment of persistent allergic asthma, then later for the treatment of refractory chronic spontaneous urticaria. 5 The current knowledge of omalizumab on cutaneous inflammatory diseases is that the drug decreases IgE levels, IgE receptors, mast cells' ability to release contained substances, and the action of IgE autoantibodies against autoantigens. 5 Despite ongoing speculation on the drug's anti-inflammatory pathways, treatment of Wells syndrome with omalizumab has been shown to be effective. 2,3,6 To date, our case is the seventh case of Wells syndrome that was successfully treated with omalizumab (Table 1). Although it is imperative that more research be done to elucidate omalizumab's pharmacological mechanism of action on the specific pathology of Wells syndrome, omalizumab may be an effective treatment option for refractory cases of this disease. This case report aims to highlight another instance of omalizumab's success to add to the Wells syndrome literature.