QuestionSBA
QuestionChoice
This patient's presentation of polygonal plaques with fine white lines (Wickham's striae), and the development of lesions at sites of injury describes Koebner's phenomenon, all keeping in line with a diagnosis of lichen planus, which is primarily a clinical diagnosis. This is managed with topical corticosteroids.
10035438
b
Topical corticosteroids
QuestionChoice
The most likely diagnosis is lichen planus. Intralesional injections may be considered if the disease is refractory to other treatments. The next most appropriate step, however, is to carry out a biopsy to confirm the diagnosis and exclude malignant changes.
10035440
d
Intralesional steroid injections
QuestionChoice
The clinical history and findings are suggestive of lichen planus, a chronic inflammatory skin condition. In people with coloured skin, lesions may appear dark rather than purple. The fine white lines on the lesions are Wickham's striae, and the development of lesions at sites of injury describes Koebner's phenomenon. This is primarily a clinical diagnosis and a skin biopsy would be undertaken to confirm the diagnosis and check for any malignant changes if there was any diagnostic uncertainty.
10035437
a
Skin biopsy
QuestionChoice
Oral immunosuppressants may be considered in lichen planus refractory to topical therapy. This is not the most appropriate next step. A skin biopsy should be obtained first to confirm the diagnosis and exclude malignancy.
10035441
e
Oral azathioprine
QuestionChoice
The most likely diagnosis is lichen planus. Tacrolimus may be commenced to spare steroid use, however this would not be the next most appropriate step.
10035439
c
Topical tacrolimus
Concept
Chapter
2693
6131
Lichen planus
Topic
144
Dermatology
19491
A skin biopsy is often used to diagnose lichen planus by examining a sample of skin tissue for characteristic signs such as lymphocytic infiltration and basal cell degeneration.
A 45-year-old African man is referred to the dermatology clinic for investigation of skin lesions that have appeared over the past year. He describes these as intensely itchy and notices that new lesions sometimes form at sites of injury.

On examination, multiple dark, polygonal plaques are seen over the arms. They are crossed by fine white lines.

What is the most appropriate next step?
b