Subcutaneous Sweet Syndrome Presenting as Cellulitis in a Pregnant Female

Giant Cellulitis-Like Sweet Syndrome Masquerading As Cellulitis and Shingles: A Case Report and Literature Review

Sweet syndrome (SS) is also known as acute febrile neutrophilic dermatoses. Clinically, SS features fever, arthralgias, and the sudden onset of an erythematous rash. The morphologies of skin lesions in SS are heterogenous, varying from papules, plaques, and nodules to hemorrhagic bullae, which sometimes makes the diagnosis of SS more challenging. We report a 62-year-old obese male with a history of chronic myeloid leukemia in remission for 10 years who presented with a rash for five days. The patient reported prodromal flu-like symptoms with subjective fever, malaise, cough, and nasal congestion followed by a sudden onset, painful, non-pruritic rash. The rash was associated with bilateral hip arthralgias and abdominal pain. The patient denied any recent travel, exposure to sick contacts, or the use of any new medications. Physical examination showed a well-demarcated, non-blanching, confluent, erythematous plaque involving the bilateral buttocks and extending to the lower back and flanks with coalescent "juicy"-appearing plaques and flaccid bullae. No oral or mucosal involvement was noted. Laboratory investigations revealed mild leukocytosis, elevated inflammatory markers, and acute kidney injury. The patient was started on antibiotics given the cellulitis-like skin lesions, leukocytosis with neutrophilia, and elevated inflammatory markers. Dermatology was consulted, who attributed the patient's rash to shingles and recommended initiating acyclovir and obtaining a skin biopsy. However, the patient's rash and arthralgias worsened with anti-viral treatment while awaiting pathology results. Antinuclear antibodies, complement, human immunodeficiency virus, hepatitis panel, blood cultures, and tumor markers were all negative. Flow cytometry showed no evidence of hematopoietic neoplasms. The skin punch biopsy revealed dense neutrophilic infiltration in the dermis with no evidence of leukocytoclastic vasculitis, consistent with acute neutrophilic dermatoses. The diagnosis of giant cellulitis-like Sweet syndrome was established, and the patient was started on prednisone 60 milligrams daily. His symptoms improved promptly with steroid treatment. Our case suggests that SS can camouflage a wide spectrum of diseases, including cellulitis, shingles, vasculitis, drug eruptions, leukemia cutis, and sarcoidosis, which emphasizes the importance of keeping a high index of suspicion for SS when assessing the clinical constellations of fever, neutrophilia, and erythematous plaques suggesting atypical cellulitis. Approximately 21% of Sweet syndrome is associated with malignancy. Sweet syndrome can precede, concur with, or follow the onset of malignancy. Due to the lack of a systematic approach to patients with SS, under-investigation and diagnostic delays are common. Therefore, further screening and continuous monitoring in patients with SS becomes especially important in facilitating the early detection of a potential underlying malignancy and assists in initiating adequate therapy.

New Practical Aspects of Sweet Syndrome

Sweet syndrome (SS), or acute febrile neutrophilic dermatosis, is an inflammatory, non-infectious skin reaction characterized clinically by tender, erythematous papules/plaques/pustules/nodules commonly appearing on the upper limbs, trunk, and head and neck; histologically, SS is characterized by dense neutrophilic infiltrate in the dermis. SS is accompanied by fever; an elevation of inflammatory markers (e.g., erythrocyte sedimentation rate, C reactive protein) in serum may also be observed. Although most cases of SS are idiopathic, SS also occurs in the setting of malignancy or following administration of an associated drug. SS has also been reported in association with pregnancy and a burgeoning list of infectious (most commonly upper respiratory tract infections) and inflammatory diseases; likewise, the litany of possible iatrogenic triggers has also grown. Over the past several years, a wider spectrum of SS presentation has been realized, with several reports highlighting novel clinical and histological variants. Corticosteroids continue to be efficacious first-line therapy for the majority of patients with SS, although novel steroid-sparing agents have been recently added to the therapeutic armamentarium against refractory SS. New mechanisms of SS induction have also been recognized, although the precise etiology of SS still remains elusive. Here, we catalogue the various clinical and histological presentations of SS, summarize recently reported disease associations and iatrogenic triggers, and review treatment options. We also attempt to frame the findings of this review in the context of established and emerging paradigms of SS pathogenesis.