INSTRUCTION
Look at this patient's skin.
SALIENT FEATURES
History
Itching.
Drug ingestion (thiazides, phenothiazines, gold, organic mercurials, chloroquine,mepacrine, methyldopa, quinine, chlorpropamide, tolbutamide, proton pump inhibitors).
Occupational history (whether the patient is in contact with colour filmdeveloper).
Hepatitis C (erosive lichen planus is more common).ExaminationPapular, purplish, flat-topped eruption with fine white streaks (Wickham's striae) overthe anterior wrists and forearms, sacral region, ankles, legs and penis.
Proceed as follows:
Look into the mouth (buccal mucosa, tongue, gum or lips) for a lace-like patternof white lines and papules. (Remember that oral lichen planus must be differ-entiatedfrom leukoplakia.)
Examine the scalp for cicatricial alopecia.
Examine the nails for longitudinal ridging, pterygium formation/'rom the cuticle,20-nail dystrophy with roughened nail surface and brittle free nail edge, total nail loss.
Comment on eruptions that are present along linear scratch marks (Koebner'sphenomenon).
Comment on the residual hyperpigmented macules that lichen planus leaves inits wake.
Note. The three cardinal features of lichen planus are the typical skin lesions.histopathological features of T-cell infiltration of the dermis in a band pattern, and IgGand C3 immunofluorescence at the basement membrane of the dermis.
DIAGNOSIS
This patient has violaceous, flat-topped eruptions (lesion) due to lichen planus(aetiology) with several scratch marks indicating moderately severe pruritus (functionalstatus).
ADVANCED-LEVEL QUESTIONS
Mention a few conditions that present as white lesions in the mouth.
Leukoplakia.
Candidiasis.
Aphthous stomatitis.
Squamous papilloma.
Verruca vulgaris.
Secondary syphilis.Mention a few conditions in which ulcers can be found in the mouth.
Erosive lichen planus.
Pemphigus vulgaris.
Recurrent aphthous ulcers.
Beh~iet's disease.
Stevens-Johnson syndrome.
Recurrent herpes simplex.
What is the prognosis in lichen planus?
Lichen planus is a benign condition which lasts for months to years. It may be recurrent.Oral lesions may be persistent.
How would you manage these lesions?
Local measures: local steroid creams or intralesional steroids.
General measures: PUVA, isotretinoin, dapsone.
Ultraviolet light to control pruritus
Mucous membrane lesions: corticosteroids or 'swish and spit' ciclosporin.L.R Wickham (1860-1913), a French dermatologist.H. Koebner (1838-1904), a German dermatologist.