003 Utility of plucked hair direct immunofluorescence as a possible replacement for conventional skin biopsy direct immunofluorescence in immunological activity monitoring and prediction of relapse in pemphigus

Abstract

Abstract Pemphigus vulgaris (PV) is a potentially lethal chronically relapsing autoimmune bullous disorder with intraepithelial lesions affecting the skin and mucous membranes. The prediction of clinical relapse has been studied with conventional skin biopsy and plucked hair direct immunofluorescence (DIF; Daneshpazhooh M, Naraghi ZS, Ramezani A et al. Direct immunofluorescence of plucked hair for evaluation of immunologic remission in PV. J Am Acad Dermatol 2011; 65:173–7) which can be of use in timing treatment withdrawal and helping with better management. The aims of our study were to determine the association of plucked hair root DIF positivity status at baseline with clinical relapse within the study duration, and to determine the correlation between skin biopsy and plucked hair DIF. Seventy-eight consecutive patients diagnosed with PV in clinical remission on therapy, on minimal therapy or off therapy, were included after obtaining informed consent. Three-monthly follow-up was carried out for 12 months. Immunological monitoring with plucked hair DIF was done at baseline and repeated every 3 months for 1 year or a relapse was experienced, whichever occurred earlier. Conventional skin biopsy DIF was performed at baseline, at 3 months and at the time of relapse. In patients receiving adjuvant therapy during their present remission episode, discontinuation of therapy was done at inclusion, at 3 months and at 6 months, and occurrence of relapse in relation to the time point of discontinuation was assessed. Of 78 patients, 22 had disease relapse and 56 remained in complete remission. Clinical relapse during the study duration was significantly more frequent in patients who had higher mean Autoimmune Bullous Skin Disorder Intensity Score during the preceding active disease episode (P = 0.033), pruritus during the present clinical remission episode (P = 0.007) and early discontinuation (within 3 months of study inclusion) of concomitant adjuvant therapy (P = 0.007). Immunological parameters associated with clinical relapse were baseline IgG (P = 0.005) and C3 positivity (P = 0.047) in plucked hair, greater intensity of IgG and C3 positivity at baseline in plucked hair (IgG, P = 0.002; C3, P = 0.033) and skin biopsy specimens (IgG, P = 0.004; C3, P = 0.0.002), and positive hair DIF at the time of adjuvant therapy withdrawal (P = 0.017). Plucked hair DIF is a reliable technique to assess immunological remission in patients with PV who are in clinical remission and helps to guide treatment according to immunological remission status.