Maike M. Holtsche, Nina van Beek, Axel Künstner, Hauke Busch, Detlef Zillikens, Enno Schmidt
DOI: 10.2340/00015555-3748

In pemphigoid diseases, direct immunofluorescence can be used to differentiate 2 patterns of antibody deposition at the dermal–epidermal junction; u- and n-serrated pattern. The u-serrated pattern is found in epidermolysis bullosa acquisita, and n-serrated pattern in all other pemphigoid diseases. To determine the detection frequency of these serrated patterns and the optimal thickness of biopsy cryosections, 2 patient cohorts obtained form our routine autoimmune laboratory were analysed; a retrospective cohort (n = 226) and a prospective cohort (n = 156). [AQ1] In 76% (291/382) of biopsies, a pattern was recog­nized, of which 96% (278/291) and 4% (13/291) had an n- or u-serrated pattern, respectively. A u-serrated pattern was seen in all epidermolysis bullosa acquisita biopsies confirmed by serology. No antibodies against type VII collagen were detected in any of the sera from biopsies with n-serrated pattern. No differences between the detection frequencies of serrated pattern were seen with respect to age, sex, biopsy site, or section thickness, while the detection frequency was higher in patients with serum anti-BP180 reactivity compared with those without. In conclusion, serrated pattern analysis using direct immunofluorescence has a high detection frequency and specificity for epidermolysis bullosa acquisita and will further facilitate the diagnosis of latter disorder.

Pemphigoid diseases are blistering skin diseases. To diag­nose these diseases, antibody depositions at the dermal–epidermal junction can be detected in perilesional skin biopsies. To differentiate between different pemphigoid diseases, 2 patterns of antibody deposition can be found at high magnification, namely u- and n-serrated pattern. The u-serrated pattern is found in epidermolysis bullosa acquisita, and the n-serrated pattern is observed in all other pemphigoid diseases. This study analysed 382 biopsies in order to determine the detection frequency of these serrated patterns. In 76% (291/382) of biopsies, a pattern was recognized, of which 96% (278/291) and 4% (13/291) had an n- or u-serrated pattern, respectively.