Inflammatory Dermatoses of the Superficial Cutaneous Reactive Unit—Study of Morphological Features with Clinical Correlation

Abstract

Background and objectives: Inflammatory dermatoses of the superficial cutaneous reactive unit are a common and complex variety of clinical conditions. This study was undertaken to perform a detailed morphological evaluation of lesions classified in this category, and to correlate the clinical details to arrive at the most appropriate diagnosis. Methodology: Skin biopsies of clinically diagnosed/suspected cases of inflammatory dermatoses were processed and stained with hematoxylin and eosin (H&E), followed by microscopic examination. Results: A total of 160 skin biopsies of superficial inflammatory dermatoses were studied. Lesions were categorized into papular/nonvesiculobullous (non-VB) (142 cases/88.75%) and VB (18 cases/11.25%) lesions. Papular lesions were frequent in males, with a peak incidence in the fourth decade. Patients presented mostly with pigmented plaques and papules over the extremities. Papular lesions were categorized based on epidermal changes: 8 cases without epidermal changes and 134 with epidermal changes. Lesions with epidermal changes were further categorized into interface dermatitis (60 cases), psoriasiform dermatitis (58 cases), and spongiotic dermatitis (16 cases). Commonly reported lesions were lichen planus (LP) with its variants followed by psoriasis vulgaris. VB lesions were common in the third and fourth decades, predominantly in females. These patients presented mostly with generalized vesicles. Common lesions reported were erythema multiforme (seven cases) and pemphigus vulgaris (six cases). Of the 160 cases, clinicopathological concordance was seen in 156 cases (97.5%) and discordance in 4 cases (2.5%). Interpretation and conclusion: The incidence of superficial inflammatory dermatoses in our study was comparable with those reported in other studies. Despite advances in molecular techniques, morphology remains the gold standard for the diagnosis and prognosis of many inflammatory dermatoses. This study emphasizes the importance and utility of a systematic approach to superficial inflammatory dermatoses which is relevant from the treatment perspective.