Context: Autoimmune blistering diseases (AIBDs) are characterized by autoantibodies directed against antigens of skin. Direct immunofluorescence (DIF) study helps in confirming the diagnosis where histopathology alone is noncontributory.
Aims: This study aimed to evaluate the clinicopathological and DIF features of intraepidermal AIBD and to assess their relative diagnostic significance.
Materials and methods: It was an institution-based observational study. A total of 34 patients were studied over a period of 1½ years in the Department of Pathology in collaboration with the Department of Dermatology of a tertiary care hospital. The clinical, pathological, and DIF features were evaluated and documented.
Statistical analysis: Data were analyzed by statistical tests using GraphPad InStat.
Results: Pemphigus vulgaris (PV) was the predominant type with 18 (53%) cases followed by 15 (44%) cases of pemphigus foliaceus (PF) and a single case of pemphigus erythematosus (PE). The age of the patients ranged from 17 to 85 years. Overall, there was a female preponderance in the study group. The most common presenting feature was pruritus (58.82%). Tzanck smear showed the presence of acantholytic cells in thirty (88.24%) patients. Characteristic histopathological features were present in all the cases of PV and PF except one case of PF which was found to be a case of PE. DIF study showed intraepidermal deposition of intercellular immunoglobulin G (IgG) and C3 both in PV and PF. The case of PE showed epidermal "antinuclear antibody" staining with IgG.
Conclusion: Immunofluorescence study may be used as an additional tool for confirmation of diagnosis where histopathology alone is inconclusive.
Keywords: Direct immunofluorescence; histopathology; immunobullous disorder; tzanck smear.