The Study of Clinical Variations and Histopathological Findings in Polymorphous Light Eruption

Abstract

BACKGROUND Epstein. S in 1942 described PMLE under the name of Prurigo aestivalis. He first hypothesised that PMLE represents a form of delayed-type hypersensitivity response to an endogenous, cutaneous UV-induced antigen, because of the hours or days delay between sun exposure and manifestation of symptoms, and the histological appearance of lesional skin. Firm evidence; however, has been lacking and the responsible allergen has not been identified. PMLE a specific entity encompassing six clinical manifestations: Small erythematous papulovesicles, eczematous lesions, large papules, oedematous plaques, prurigo nodules and erythema multiforme-like lesions. The histological features of PMLE are characteristic, but not pathognomonic and vary with the different clinical presentation. A sincere effort has been put in this study to understand the clinical and histopathological features of polymorphic light lesions. The study is intended to help the practising physicians and dermatologists to diagnose the pathology on time and intervene before it develops into complications. METHODS Material for the present study consisted of 100 cases of clinically diagnosed untreated cases of polymorphous light eruption, who were attending the skin and STD and Leprosy Department, Kakatiya Medical College, Warangal, during January 2014 to Dec 2014 were selected for this study. The patients were selected randomly irrespective of age, sex, socioeconomic status. RESULTS Histopathology showed perivascular lymphocytic infiltration in the dermis in majority of our cases (93.33%) and clinicohistopathological correlation was observed in most cases; hence apart from clinical examination, histopathological examination plays an important role in diagnosing PMLE. CONCLUSION 56 percent of the patients complained pruritus followed by burning. The study was similar to other studies in comparison.

Polymorphous Light Eruption– An Indian Scenario

“…[ 19 20 21 22 ] The possible mechanisms involved in pathogenesis are given in the form of a chart [ Figure 1 ] which incorporates various factors involved. [ 23 24 25 26 27 ]…”

“…The action spectrum involves UVA, UVB, and visible light. [ 25 36 ] There is also an interesting observation of PMLE preferentially involving the sites of hypopigmented scars. [ 37 ]…”

“…Sunburn cells are notably sparse or absent. [ 25 ] The histopathology varies depending upon the morphological type. Histopathological differential diagnoses for polymorphous light eruption includes reticular erythematous mucinosis, Jessener's lymphocytic infiltrate, lupus erythematosus, and actinic reticuloid.…”