Treatment of Sweet Syndrome
Systemic corticosteroids are the first-line treatment for Sweet syndrome, with prednisone or prednisolone at 0.5-1 mg/kg/day (typically 30-60 mg daily) providing rapid symptom resolution within 24-72 hours. 1, 2, 3
First-Line Therapy: Systemic Corticosteroids
Prednisone/prednisolone 0.5-1 mg/kg/day (typically 30-60 mg daily) should be initiated immediately upon diagnosis, as this represents the therapeutic gold standard with dramatic improvement of fever, arthralgias, and skin lesions within 48-72 hours 2, 3, 4
Continue daily dosing for 4-6 weeks, then taper gradually over 2-3 months to minimize relapse risk 2, 3
Expect fever and systemic symptoms to resolve within 24-48 hours, with skin lesions clearing within 7-14 days 2, 5
Important caveat: Approximately one-third of patients with classical Sweet syndrome experience recurrence after treatment discontinuation, requiring vigilant monitoring 3
Alternative First-Line Agents (When Corticosteroids Contraindicated)
When systemic corticosteroids are contraindicated or in patients with concurrent infection:
Potassium iodide: Start at 300 mg three times daily, increase to 900-1500 mg daily if needed; provides rapid resolution comparable to corticosteroids 2, 3, 4
Colchicine: 0.5-1.5 mg daily; effective as monotherapy with rapid symptom improvement 2, 3, 4
Indomethacin: 150 mg/day for first week, then 100 mg/day for 2 additional weeks; demonstrated 94% response rate (17/18 patients) with fever/arthralgias resolving within 48 hours and skin lesions clearing in 7-14 days 5
Localized Disease Management
- High-potency topical corticosteroids or intralesional corticosteroid injections can be used for limited, localized lesions as monotherapy or adjuvant therapy 2, 3
Second-Line Systemic Agents (Refractory or Recurrent Cases)
For patients who fail first-line therapy or have frequent relapses:
Dapsone: 50-200 mg daily (requires G6PD screening and monitoring for hemolysis and methemoglobinemia) 2, 3, 4
Cyclosporine: 3-5 mg/kg/day in divided doses (requires blood pressure and renal function monitoring) 2, 3, 4
Clofazimine: 100-200 mg daily (less effective than corticosteroids but useful in refractory cases) 2, 3
Disease-Specific Considerations
Malignancy-associated Sweet syndrome (MASS): Treatment of the underlying malignancy (typically acute myelogenous leukemia) is essential, as the dermatosis often resolves with cancer treatment; systemic corticosteroids remain first-line for symptomatic management 3, 4
Drug-induced Sweet syndrome (DISS): Withdrawal of the offending medication (most commonly G-CSF) may lead to spontaneous resolution without additional therapy; if symptoms persist, use systemic corticosteroids 2, 3
IBD-associated Sweet syndrome: Systemic corticosteroids are effective, with consideration of immunomodulators (azathioprine) or anti-TNF agents (infliximab, adalimumab) for resistant or frequently relapsing cases 1
Emerging Therapies
- Biologic agents (anti-TNF, anti-IL-1) and small molecules have shown efficacy in case reports for refractory disease, though evidence remains limited 4
Critical Pitfalls to Avoid
Do not delay treatment waiting for biopsy confirmation if clinical presentation is classic; initiate corticosteroids empirically as delayed treatment does not alter diagnostic accuracy 3
Do not use antibiotics as primary therapy unless secondary bacterial infection is documented; Sweet syndrome is a sterile neutrophilic infiltrate 2, 3
Screen for underlying malignancy in all patients, particularly those over 50 years or with atypical features, as Sweet syndrome may be the first manifestation of occult cancer 3, 4
Monitor for spontaneous resolution in drug-induced cases after medication withdrawal before initiating systemic therapy 2, 3