A study of clinical, histopathological and direct immunofluorescence diagnosis in pemphigus group Utility of direct immunofluorescence

AIMS: To determine the diagnostic accordance between histopathological and direct immunofluorescence diagnosis of patients with autoimmune vesiculobullous skin diseases. BACKGROUND: The term pemphigus refers to a group of autoimmune blistering diseases mediated by auto-antibodies directed against desmoglein proteins. The differentiation between the various bullous diseases is important for treatment and prognosis. Direct immunofluorescence microscopy is still the gold standard in differentiating these diseases. METHODS: Patients with clinical diagnosis of vesiculobullous dermatitis from pemphigus group were included in the study. We retrospectively analyzed histopathologic and direct immunofluorescence results from skin or mucosal samples over 15-year period. RESULTS: 81 patients were included. The accordance was good in pemphigus vulgaris and pemphigus herpetiformis, but low in pemphigus vegetans, pemphigus foliaceus and pemphigus erythematosus. No accordance was in Hailey-Hailey disease and Grover´s disease. Uncommon result in our analysis included: intraepidermal IgG and IgM depositions at DIF in one Grover´s disease patient. CONCLUSION: Our results confirmed the relevance of direct immunofluorescence assays as a necessary diagnostic method for the definitive diagnosis of autoimmune blistering disease in the case, where the clinical feature and the results of histopathology are not clear (Tab. 4, Fig. 5, Ref. 26).