Sweet's syndrome: a review of current treatment options

Sweet's syndrome was originally described in 1964 by Dr Robert Douglas Sweet as an 'acute febrile neutrophilic dermatosis'. The syndrome is characterized by pyrexia, elevated neutrophil count, painful red papules, nodules, plaques (which may be recurrent) and an infiltrate consisting predominantly of mature neutrophils that are diffusely distributed in the upper dermis. In addition to skin and mucosal lesions, Sweet's syndrome can also present with extra-cutaneous manifestations. Sweet's syndrome can be classified based upon the clinical setting in which it occurs: classical or idiopathic Sweet's syndrome, malignancy-associated Sweet's syndrome and drug-induced Sweet's syndrome. Systemic corticosteroids have been considered the 'gold standard' for the treatment of patients with Sweet's syndrome; in addition, treatment with topical and/or intralesional corticosteroids may be effective as either monotherapy or adjuvant therapy. However, spontaneous resolution of the symptoms and lesions has occurred in several patients with Sweet's syndrome for whom disease-specific therapeutic intervention was not initiated and in some of the patients with drug-induced Sweet's syndrome after withdrawal of the dermatosis-causing medication. Oral therapy with either potassium iodide or colchicine typically results in rapid resolution of Sweet's syndrome symptoms and lesions; therefore, in patients with Sweet's syndrome who have a potential systemic infection or in whom corticosteroids are contraindicated, it is reasonable to initiate treatment with these agents as a first-line therapy. Indomethacin, clofazimine, dapsone, and cyclosporine have also been effective therapeutic agents for managing Sweet's syndrome. However, indomethacin and clofazimine appear less effective than corticosteroids, potassium iodide, and colchicine. Appropriate initial and follow-up laboratory monitoring is necessary when treating with either dapsone or cyclosporine because of the potential for severe adverse drug-associated effects. Systemic antibacterials with activity against Staphylococcus aureus frequently result in partial improvement of Sweet's syndrome lesions when they are impetiginized or secondarily infected. In some patients with dermatosis-associated bacterial infections, organism-sensitive specific systemic antibacterials have been helpful in the management of their Sweet's syndrome. Although patients with hematologic malignancy-associated Sweet's syndrome often receive cytotoxic chemotherapy agents and antimetabolic drugs for the treatment of their underlying disorder, these agents are seldom used solely for the management of the symptoms and lesions of Sweet's syndrome. The treatment of patients with Sweet's syndrome with either etretinate or interferon-alpha have been reported as single case reports; both patients had improvement of not only their Sweet's syndrome lesions, but also their associated hematologic disorder.