Inflammatory, Papulosquamous, and Eczematous Dermatoses — WACS Viva & Clinical Scenarios (Dermatology and Venereology)

Exam-style inflammatory, papulosquamous, and eczematous dermatoses viva scenarios with examiner probes and model answers for Internal Medicine candidates.

Scenarios covered

• SCENARIO 1: A 34-year-old man presents with a 6-month history of well-demarcated, hyperpigmented, scaly plaques over his extensor surfaces (elbows, knees, and lumbosacral region) accompanied by pitting and oil-drop discoloration of the fingernails. Examination reveals silvery-white scales that bleed pinpoint droplets upon gentle scraping. Outline the underlying pathophysiological mechanism, histopathological hallmarks, and a structured management algorithm spanning topical agents, phototherapy, and systemic immunomodulators.
• SCENARIO 2: A 28-year-old woman presents to the clinic with severe, intractable pruritus, flexural lichenified plaques, xerosis, and recurrent facial dermatitis since childhood. Detail the diagnostic criteria used to establish atopic dermatitis, the genetic and immunological defects involved in skin barrier disruption, the potency classification ladder of topical corticosteroids, and strategies for proactive maintenance versus acute flare management.
• SCENARIO 3: A 62-year-old man with a known history of chronic plaque psoriasis treated irregularly with over-the-counter herbal remedies and intermittent oral dexamethasone presents with acute, widespread erythema and fine exfoliation involving 92% of his total body surface area, accompanied by chills, pedal oedema, and tachycardia. Discuss the clinical approach to establishing the diagnosis of erythroderma (exfoliative dermatitis), the acute metabolic and hemodynamic complications, and the emergency stabilization protocol.
• SCENARIO 4: A 42-year-old male industrial worker presents with recurrent vesicular and eczematous eruptions on the dorsum of both hands and wrists that worsen towards the end of the workweek and improve during annual leave. Describe the clinical differentiation between allergic contact dermatitis and irritant contact dermatitis, the diagnostic methodology and timing of patch testing, and long-term preventive occupational strategies.
• SCENARIO 5: A 38-year-old woman presents with intensely pruritic, violaceous, polygonal, flat-topped papules distributed symmetrically on her flexor wrists and ankles, along with reticular white lacy streaks on the buccal mucosa. Detail the clinical variants, aetiological associations, characteristic interface dermatitis histopathology, and stepwise therapeutic options.