Table 1.

Differential diagnosis of lupus band test in lupus erythematosus from other conditions

Clinical condition	Comments
Positive lupus band test	Granular band or closely spaced, vertically oriented fibrils at dermoepidermal junction; sometimes a thick, homogeneous band.
Healthy sun-exposed skin	May demonstrate positive lupus band test.
	The band is usually less intensive and frequently focal or interrupted.
	No reactivity is seen in sun-protected skin.
Autofluorescence of dermal collagen and elastin fibers	Might simulate a positive lesional lupus band test.
	Artifactual nature of this false-positive finding becomes apparent at higher magnification.
Bullous pemphigoid	Sharply defined thin linear band at dermoepidermal junction.
	Presence of circulating antibodies against basement membrane components is helpful for a correct diagnosis.
Porphyrias	Fluorescence of the dermoepidermal junction is less intense than that found in dermal blood vessels, which is exactly the reverse of what is seen in lupus erythematosus.
	Complement is rarely found in the band.
Rosacea	The band is less intensive and frequently focal or interrupted.
Polymorphic light eruption	The band is less intensive and frequently focal or interrupted.