Comparative Study of Direct Immunofluorescence in Discoid Lupus Erythematosus and Bullous Pemphigoid

Abstract

Immunoreactants are found in the epidermal basement membrane in both lupus erythematosus and bullous pemphigoid (BP). To our knowledge, there are no comparative studies on direct immunofluorescence (DIF) of discoid lupus erythematosus (DLE) and BP. The authors studied DIF of lesional skins in 9 patients (2 males and 7 females) with DLE and 29 patients (11 males and 18 females) with BP to disclose the difference between these 2 diseases. IgG deposition was significantly more frequent at the epidermal basement membrane zone (BMZ) in the BP group than in the DLE group; however, IgA and IgM depositions were significantly more frequent at both the epidermal and follicular BMZs in the DLE group than in the BP group. In addition, the mean number of positive immunoreactants at both the epidermal and follicular BMZs was significantly larger in the DLE group than in the BP group. On an average, ≥3 immunoreactants were seen at the epidermal and follicular BMZs in DLE, whereas ≤2.5 immunoreactants were seen in BP. DIF may contribute to the differentiation between these 2 diseases.

Direct Immunofluorescence in Cutaneous and Systemic Lupus Erythematosus: A Literature Review

“…The positive yield ranges from 27.2%-100% in lesion areas and 45.5%-69.2% in non-lesion areas. 14,16,22,23,33,35,[40][41][42][43][44][45][46][47][48] ENS has also been found, but at a lower frequency than ACLE and SCLE. DIF tests of oral DLE lesions have also revealed deposits of multiple immunoglobulins at the DEJ with either granular or homogeneous bands, similar to DLE lesions on glabrous skin.…”

Cutaneous Manifestations of “Lupus”: Systemic Lupus Erythematosus and Beyond

“…Immunoglobulin M (IgM) and complement 3 (C3) are most commonly detected, and the presence of additional immunoreactants (i.e., IgG, IgA, C1q, and C4), an uninterrupted linear band, and increased intensity of staining all increase the specificity and predictive value of this finding. DIF can be useful for distinguishing cutaneous lupus from other inflammatory skin conditions [ 18 , 19 ]. Many studies have shown that SLE patients will frequently have positive DIF when sun-protected, nonlesional (i.e., no rash) skin is biopsied [ 20 ].…”

“…Many studies have shown that SLE patients will frequently have positive DIF when sun-protected, nonlesional (i.e., no rash) skin is biopsied [ 20 ]. Of note, a nonlesional lupus band test can be positive in patients with other autoimmune diseases [ 18 , 19 , 21 , 22 ]. It is important to note that histopathology with DIF cannot differentiate between the rashes of lupus and dermatomyositis, as both may have similar findings [ 18 , 21 ].…”

Bullous Pemphigoid in Patients Receiving Immune-Checkpoint Inhibitors and Psoriatic Patients—Focus on Clinical and Histopathological Variation

“…Therefore, diagnosis should be routinely supported by IF and DIF. Typically, linear deposits of C3 and immunoglobulins (most often IgG) along the dermoepidermal junction are detected [4]. The appearance of BP with the above-mentioned consistent immunofluorescence features in fully developed lesions of lichen planus has been termed lichen planus pemphigoides.…”