Cutaneous Vasculitis and Neutrophilic Dermatoses (Sweet's, Pyoderma Gangrenosum) MCQs

Dermatology · 14 free questions with answers & explanations.

1. Sweet's syndrome (acute febrile neutrophilic dermatosis) is characterised by painful erythematous plaques with dermal neutrophilic infiltrate. The condition most commonly associated with Sweet's syndrome is:
2. Pyoderma gangrenosum (PG) begins as a painful pustule or nodule that breaks down into an ulcer with a characteristic undermined violaceous border. The pathological mechanism underlying PG is:
3. Henoch-Schönlein purpura (IgA vasculitis) most commonly involves which vessel calibre and immunoreactant?
4. A 45-year-old woman with Crohn's disease develops multiple, rapidly extending, painful ulcers on both legs with raised, undermined, purplish-blue borders. Wound culture is sterile. The FIRST-LINE systemic treatment of choice is:
5. A 45-year-old woman with known inflammatory bowel disease develops a rapidly expanding, painful ulcer with a purulent, undermined, violaceous border on her leg. The pathergy test is positive. The most appropriate first-line systemic treatment is:
6. Sweet's syndrome (acute febrile neutrophilic dermatosis) is MOST commonly associated with which type of underlying malignancy?
7. Histopathology of a skin biopsy from a tender, erythematous plaque in a patient with Sweet's syndrome would show:
8. In Henoch-Schönlein Purpura (IgA vasculitis), the distinguishing DIF finding from skin biopsy is:
9. A 45-year-old woman with recently diagnosed acute myeloid leukaemia develops sudden-onset painful, oedematous, erythematous-violaceous plaques on the arms and face with fever and neutrophilia >8000/mm³. Skin biopsy shows dense dermal neutrophilic infiltrate without vasculitis. What is the diagnosis and its pathognomonic treatment response?
10. Pyoderma gangrenosum (PG) demonstrates pathergy. A surgeon performing debridement of a suspected PG ulcer on the leg of a patient with ulcerative colitis would most likely observe which outcome?
11. A 28-year-old man develops palpable purpura on the lower legs 10 days after a streptococcal throat infection. Skin biopsy shows leukocytoclastic vasculitis with IgA deposits on DIF. Which organ must be evaluated first given the systemic implications of this finding?
12. A 55-year-old woman with known ulcerative colitis develops a rapidly enlarging, deeply ulcerated wound on her lower leg following a minor trauma (phlebotomy). The wound has a violaceous undermined border with a boggy base and surrounding erythema. She describes the onset as extremely painful. Which phenomenon is associated with this condition and influences surgical management?
13. 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:
14. A 35-year-old man presents with palpable purpura on the lower limbs. Biopsy shows fibrinoid necrosis of vessel walls with neutrophilic infiltrate and leucocytoclasia (nuclear dust) involving small vessels in the superficial dermis. Direct immunofluorescence shows IgA deposition in vessel walls. What is the diagnosis and the underlying mechanism?