A Study of Interface Dermatitis With Clinical Correlation

Abstract

BACKGROUND:Interface dermatitis (ID) is defined as an inflammatory skin disease in which the junction between the papillary dermis and the epidermis is obscured. They are so named because they are cell mediated immune reactions whose targets are basal keratinocytes that reside above the dermo-epidermal junction. Interface dermatitis encompasses multiple clinical entities with diverse histological features. This study is aimed at understanding the various associated histological features with clinical correlation of conditions in which Interface Dermatitis is the most important histopathologic finding. This will help us in arriving at a more specific diagnosis by light microscopy. MATERIALS AND METHODS:The study was conducted over a period of two and a half years. Skin biopsies showing interface dermatitis as a major histological finding were studied in detail and classified according to Le Boit's classification. PAS staining was done to highlight pathology of basement membrane. Normal skin biopsies & biopsies with an unrelated condition were taken as control. Correlation between clinical features, clinical diagnosis and histological diagnosis was assessed. RESULTS: 71 cases showing interface dermatitis were studied. The most common age range was between 50-59 years with a female preponderance. Majority of the cases belonged to type I interface dermatitis with lichen planus being representative of this type. PAS staining revealed basement membrane disruption in many of the cases. CONCLUSION: Interface dermatitis includes diverse entities which have overlapping features at the clinical and histopathological level. Hence, a detailed light microscopic examination aided further by special tests such as immunofluorescence will help at arriving at a definitive diagnosis. More studies are also needed in order to identify specific features to redefine each of the entities.