lichen planus

objectives

To define and list the common papulo squamous diseases Able to recognize clinical features, diagnosis complications and treatment of lichen planus Able to define ,diagnose and treat pityriasis rosea

Common Papulo squamous diseases((scaly rashes or scaly erythematous rashes

Psoriasis Lichen planus Pityriasis rosea Tinea corporis Pityriasis versicolor Discoid eczema Seborheic dermatitis Secondary syphilis Drug eruptions

Lichen planus

طحالبLichen planus (Greek leichen, “tree moss”; Latin planus, “flat”) is a common inflammatory disorder that affects the skin, mucous membranes, nails, and hairThe four Ps—purple, polygonal, pruritic, papule

Spain

Lichen planus
At least two-thirds of cases occur between the ages of 30 and 60 years of age. Male to female ratio is one

Lichen planus

It is an immunologic mechanisms mediate the development of lichen planus. Cell-mediated immunity plays the major role in triggering the clinical expression of the disease. (Both CD4+ and CD8+ )T cells are found in lesional skin CD8+ T cells are cytotoxic cells attacking basal keratiocytes



Pathology: Basal epidermal keratinocyte damage and lichenoid interface lymphocytic reaction.

Lesions: Symmetric, grouped, erythematous to violaceous, flat-topped, polygonal papules. 4p Wickham s striae white network Distribution: Widespread, predilection for flexural aspects of arms and legs.

Wickham s striae

by ALMANAR

CONFIGURATION OF LESIONS

Annular Lichen Planus. They occur in blacks and are more common on the penis and scrotum Actinic lichen planus, seen in subtropical zones on sun-exposed, dark-skinned young adults and children Linear Lichen Planus. Papules of lichen planus may develop a linear pattern secondary to trauma (koebnerization)

Clinical variants according to MORPHOLOGY OF LESIONS

Hypertrophic occurs on the extremities and tends to be the most pruritic variant Lesions are thickened and elevated, purplish or reddish-brown in color, and hyperkeratotic. Vesiculo bullous Lichen the development of vesicles and bullae within the lesions, Bulla arising in oral can lead to painful erosions Erosive and Ulcerative Follicular Sites of predilection include the trunk and the scalp

The thickened lesions characteristic ofhypertrophic lichen planus on the shins.

Site of involvement
Mouth examination Mucosal lichen planus Nail examination Lichen planus of nail Lichen planopilaris Scalp examination Complications Permanent nail loss Scarring alopecia


Course
last for one year Hypertrophic many years Leave brown macules

Treatment

The mainstay of treatment for lichen planus is strong topical corticosteroids. Resistant localized lesions, such as on the shins, may be treated with intralesional steroids or with steroids under occlusive dressingsSystemic treatment of lichen planus has traditionally been with corticosteroids, usually at doses equivalent to 20–40mg prednisolone initially, reduced over a period of a few weeks. cyclosporine appears to be the most consistently useful. PUVA photo chemotherapy

Question? in Wickham's striae is characteristically seen

Pityriasis rosea Lichen planus Psoriasis Pityriasis versicolor Tinea corporis

Pityriasis rosea

Pityriasis rosea is self-limiting acute exanthematous eruption with a distinctive morphology. First, a single (primary, or "herald") plaque lesion develops, usually on the trunk, and 1 or 2 weeks later a generalized secondary eruption develops in a typical distribution pattern remits spontaneously in 6 weeks. 50% itch

There is some evidence that it is viral in origin Age of Onset 10 to 40 years, but can occur rarely in infants and old persons. Season Spring and fall. Etiology Herpes virus type 7 is suspected.

Diff diagnosis

Tinea corporis herald patch more than 3 months Guttate psoriasis Secondary syphilis

Collarette scale

Scarring alopacia

Psoriasis Pityriasis alba Pityriasis rosea Seborrheic dermatitis Lichen planopilaris


Treatment It usually causes few symptoms, but a topical corticosteroid speeds up the resolution.Oral erythromycin daily (1 gm in four equally divided doses for 2 weeks in adultsUltraviolet light B (UVB), administered in five consecutive daily erythemogenic exposures, results in decreased pruritus and hastens the involution of lesions

Summary

Scaly erythematous rashs patchy or papular may resemble psroriais History, location and clinical features may facilitate diagnosis and some time even lab test and biopsy are Needed Lichen with its four P may end in serious complicatin While pity rosea is self limmiting which may similate tinea corporis for its herald patch and secondary of syphlis in the wide spread stage