ABSTRACT
Lichen planus ■ Erythematous to violaceous, flat-topped, polygonal papules
with fine, whitish reticulations termed Wickham striae ■ Distributed symmetrically over flexural areas of extremities ■ Pruritus usually present ■ Hypertrophic lichen planus extremely pruritic ■ Presence of Koebner phenomenon ■ White, reticulated pattern occurs with oral involvement ■ Nail pterygium or complete loss of nail plate
Lupus erythematosus and ■ See Chapter III other connective tissue disorders
Lichenoid drug reactions ■ Initiated by many drugs, such as β-adrenergic blockers (latent period of 1 year), penicillamine (latent period of 2 months-3 years), angiotensin-converting enzyme inhibitors, especially captopril (latent period of 3-6 months)
■ Usually resolves 2 to 4 months after discontinuation of offending drug
Lichenoid photodermatoses ■ Lesions appear eczematous with a photodistributed pattern ■ Drugs that induce a photodistributed lichenoid reaction
include carbamazepine, chlorpromazine, ethambutol, quinine, tetracyclines, thiazide diuretics, and furosemide
■ Generally resolve 3 to 4 months from discontinuation of offending drug
Direct Immunofluorescence ■ Shaggy BMZ pattern for fibrinogen (Fig. 4.1) ■ Cytoid bodies for IgM and IgA, occasionally IgG, C3,
and fibrinogen (Fig. 4.2)
Indirect Immunofluorescence ■ ANA for lupus erythematosus
Fig. 4.1 Shaggy BMZ: fibrinogen
Fig. 4.2 Scattered and clumped cytoid bodies: IgM
