A 45-year-old woman develops acute onset of tender erythematous plaques and nodules on her face and upper arms with fever (38.8°C). CBC shows neutrophilia (11,500/µL). She recently completed chemotherapy for AML. Biopsy shows dense neutrophilic infiltrate in the dermis without vasculitis or leucocytoclasia. This is:
- A Erythema nodosum
- B Sweet's syndrome (Acute febrile neutrophilic dermatosis) ✓
- C Cutaneous polyarteritis nodosa
- D Leukocytoclastic vasculitis
Explanation
Sweet's syndrome (acute febrile neutrophilic dermatosis) presents with the classic triad: abrupt-onset tender erythematous plaques/papules/nodules, fever, and peripheral neutrophilia. Biopsy confirms dense neutrophilic dermal infiltrate WITHOUT vasculitis — this distinguishes it from leukocytoclastic vasculitis (which shows fibrinoid necrosis and leucocytoclasia). Malignancy-associated Sweet's (most commonly AML, myelodysplastic syndrome) is an important cause. The drug-induced form is also recognised (G-CSF, azathioprine). Response to systemic corticosteroids is dramatic.
Reference: Neena Khanna Illustrated Synopsis of Dermatology & STD, 6th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.