Direct immunofluorescence findings in cicatricial alopecia: A retrospective study of 155 cases

Objectives: To study the direct immunofluorescence (DIF) in cicatricial alopecia (CA) patients. Materials and Methods: Approximately, 155 skin biopsies from CA patients examined over 7 years (2009–2015). Special stains and Hematoxylin and Eosin were performed, and final histopathological diagnosis was made. DIF (against anti-IgG, IgM, C3, IgA, and fibrinogen) on all these cases and patterns were noted. The descriptive statistics were applied along with ANOVA test. Results: Approximately, 155 patients with Male: Female = 1.24:1, age 7–65 years. In total, 57 cases were of Lichen planopilaris (LPP; 36.7%), 22 Lichen planus (LP; 14.2%), 22 Psuedopalade of Brocq (PPB; 14.2%),16 discoid lupus erythematosus (DLE; 10.3%), 8 end-stage scarring alopecia (ESSA; 5.2%), 2 cases each of Fungal folliculitis (FF), and Folliculitis decalvans (FD; 1.3% each), and in 26 cases, no specific diagnosis could be reached were collectively kept in the category of non-specific findings (NSP; 16.7%). On DIF: LPP positive for IgG = 4 cases (7%), IgM = 26 (45%), IgA = 11 (19.3%), C3 = 16 (28.1%), and fibrinogen = 11 (19.3%). LP positive for IgG = 2 (9%), IgM = 18 (81%), IgA = 2 (9.1%), C3 = 10 (45%), and fibrinogen = 1 (4.5%). DLE positive for IgG = 6 (37%), IgM = 8 (50%), IgA = 1 (6.3%), C3 = 9 (56%), and fibrinogen = 1 (4.5%). Limitations: Because this was a retrospective study, clinical follow-up and treatment history of the patient could not be retrieved. Conclusions: IgG positivity helps significantly in differentiating LPP from DLE ( P 0.004) and NSP from DLE ( P 0.005). IgM positivity helps significantly in differentiating LPP from LP ( P 0.04), LP from PPB ( P 0.00) and NSP ( P 0.00). C3 positivity helps significantly in differentiating PPB from DLE ( P 0.02).