The lupus band test in systemic lupus erythematosus patients

Figures & data

Figure 1 Positive lupus band test at low magnification: immunoglobulin class M deposits at the dermoepidermal junction in sun-protected nonlesional skin in a 26-year-old woman with systemic lupus erythematosus (original magnification: ×100).

Figure 2 A sharply defined thin linear band at the dermoepidermal junction in pemphigoid (immunoglobulin class G deposits, original magnification:×200).

Figure 3 Partially homogenous, partially granular pattern of the lupus band test (immunoglobulin class M deposits, original magnification×200).

Figure 4 Stippled pattern of complement component 3 deposits in sun-protected nonlesional skin in patient with systemic lupus erythematosus (original magnification: ×400).

Figure 5 Shaggy pattern of complement component 3 deposits in sun-protected lesional skin in patients with subacute cutaneous lupus erythematosus.

Figure 6 Granular (lumpy) pattern of complement component 3 deposits in sun-protected nonlesional skin in patient with systemic lupus erythematosus (original magnification:×400).

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.