Diagnosis: Lichen planus
Description: Purplish papules on the back
Morphology: Papules
Site: Back
Sex: M
Age: 59
Type: Clinical
Submitted By: Nameer Al-Sudany
Differential DiagnosisHistory:
The precise cause of lichen planus is unknown, but the disease seems to be mediated immunologically. Typical lesions are violaceous, intensely itchy, flat-topped papules. White asymptomatic lacy lines, dots, and occasionally small white plaques, are also found in the mouth, particularly inside the cheeks, in about 50% of patients Scalp lesions can cause a patchy scarring alopecia. This man presented with classical lesions of LP involving mainly the trunk, scalp and oral mucous membrane mainly the inside surface of the cheeks of about 6 months duration.