Cutaneous and Mucosal Lichen Planus: A Comprehensive Review of Clinical Subtypes, Risk Factors, Diagnosis, and Prognosis

Table 5

The pattern of DIF results of potential differential diagnoses of lichen planus.

Differential	DIF pattern
Lichen planus	Globular IgM and fibrin deposition at BMZ
Aphthous ulcers	Negative
Bullous pemphigoid	Linear C3, IgG at BMZ, less common IgA
Chronic ulcerative stomatitis	Speckled or granular perinuclear IgG in the lower third and basal layer of epithelium
Dermatitis herpetiformis	Granular IgA at BMZ with concentration at the papillary tips
Discoid lupus erythematosus	Linear band or continuous granular IgG, IgA, IgM, and C3 at BMZ
Epidermolysis bullosa acquisita	Linear IgG and C3 at BMZ
Erythema multiforme	Negative
Hailey-Hailey disease	Negative
Lichen nitidus	Negative
Linear IgA bullous dermatosis	Linear IgA at BMZ, less common IgG, IgM, and C3
Mucous membrane pemphigoid	Linear IgG and C3 at BMZ, less common IgA, IgM, and/or fibrin
Paraneoplastic pemphigus	Intercellular IgG and C3 with or without BMZ involvement
Pemphigus vulgaris	Intercellular IgG (IgG1 and IgG4) in “chicken wire pattern,” less common C3 and IgM
Systemic lupus erythematosus	Linear band or continuous granular IgG, IgA, IgM, and C3 at BMZ

BMZ: basement membrane zone; DIF: direct immunofluorescence; Ig: immunoglobulin.