Direct immunofluorescence of skin and hair in pemphigus

Abstract

Background: The outer root sheath of the anagen and telogen hair is structurally similar to the epidermal layer of the skin. Hence Direct Immunofluorescence(DIF) demonstrating Antibodies to Desmoglein 1 and 3 in Pemphigus group of autoimmune bullous diseases would show a similar pattern in skin & hair. Aim: To compare DIF of skin and telogen hair in pemphigus group of patients in clinically active cases and those in remission. Method: 30 consecutive diagnosed cases of Pemphigus vulgaris (PV) (both active cases and remission) were selected for the prospective study. Other blistering diseases –Dermatitis herpitiformis, Chronic Bullous Dermatosis of childhood and vasulitis were excluded. Skin biopsy and telogen hair obtained by combing were subjected to Direct Immunoflurescence. (Fluorescein Isothyocyanate) FITC –conjugated rabbit antihuman IgG was used. The samples were viewed under fluorescence microscope using a blue filter (490 nm). Green fluorescence was observed. The pattern of staining & intensity of staining were compared. Results: 30 cases of Pemphigus included 22 cases of Pemphigus vulgaris(PV), 5 cases of Pemphigus Foliaceous(PF) and 3 of pemphigus erythematosus(PE). Pemphigus Vulgaris and Pemphigus Foliaceous patients with active disease showed strong ICS(Intercellular substance) deposits in both skin and hair. 37.5% and 50% of Pemphigus Vugaris and Pemphigus Foliaceous in remission showed weak deposits in hair only. All cases of Pemphigus Eryhtematosus showed only ICS pattern with no (BMZ) Basement membrane zone deposits. Conclusion: Direct Immunoflurescence of skin and hair are comparable in pattern and intensity. Telogen hair is a useful tool in remission period as it is easily accessible and picks up potential cases likely to develop relapse and therefore requiring close follow up. Keywords: DIF, Telogen hair, Skin, Pemphigus, Disease activity