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Figure 1. Photograph demonstrating erythematous plaques on the patient's chest.

Figure 2. Photomicrograph of dermal biopsy specimen demonstrating dermal infiltration with neutrophils (hematoxylin-eosin, original magnification ×100).

Robert Douglas Sweet first described Sweet syndrome in 1964.¹ In his report, Sweet described 8 patients with a neutrophilic dermatosis associated with acute febrile illnesses.¹ Sweet syndrome primarily affects adults 30 to 60 years of age and has a female-male ratio of 3:1. There are 4 subtypes of the syndrome: the classic type (71% of cases) and types associated with neoplasia (11% of cases), inflammatory disease (16% of cases), and pregnancy (2% of cases). The primary lesion is a sharply marginated, tender, erythematous plaque, 2 to 10 cm in diameter, that typically appears as multiple lesions on the face, neck, upper trunk, and extremities. Asymmetry of distribution is common. Onset can be abrupt and lesions may increase in size quickly. In 90% of cases, a significant illness, such as an upper respiratory tract infection, precedes the onset of lesions. Fever, myalgia, arthritis, conjunctivitis, renal involvement, and leukocytosis are common features of the syndrome.² Sweet syndrome may be associated with hematologic malignancies, although our patient had no evidence of hematologic malignancy or recurrence of colon cancer at the time the rash developed.

Histologically, a dense perivascular infiltrate composed of neutrophils without signs of vasculitis is characteristic. The neutrophils become more widespread in the dermis over time and may be present in limited amounts in the epidermis and subcutis. Dermal edema is typical, mild spongiosis and focal parakeratosis appear in the epidermis, and the vascular endothelium may be swollen. Systemic glucocorticosteroids are the treatment of choice in all patients with Sweet syndrome. A dosage of oral prednisone, 40 to 60 mg/d, followed by 4 to 6 weeks of tapering, has been successful in most cases, resulting in rapid resolution of the lesions. Recurrence is common, and the disease has been reported to last up to 10 years.³

Corresponding author and reprints: Eugene A. Woltering, MD, Department of Surgery, Louisiana State University Health Sciences Center, 1542 Tulane Ave, New Orleans, LA 70112 (e-mail: ewolte@lsuhsc.edu).