Photosensitive spongiotic/lichenoid eruption of micropapules and plaques: a morphologically distinct entity.

BACKGROUND: A distinct morphological pattern of photodermatosis has been observed with shiny skin colored to hypopigmented tiny papules, discrete or coalescing to form plaques. AIMS: To study the clinico-pathological features of patients presenting with these lesions. METHODS: A total of 72 patients were recruited. Clinical examination and skin biopsy was carried out to evaluate the morphological patterns and the histopathological features. RESULTS: In all patients, tiny discrete to coalescent papules were observed on sun-exposed sites but usually sparing the face. The condition occurred more commonly in women. Three specific histopathological patterns were observed : spongiotic (43.7%), lichenoid (22.5%), psoriasiform (18.7%) and also perivascular pattern in 5%. CONCLUSION: Photosensitive lichenoid eruption is a morphologically distinct photodermatoses that is commonly seen in Indian patients with pathological features showing mostly spongiotic changes and in some cases lichenoid changes.

Occurrence of plant sensitivity among patients of photodermatoses: a control-matched study of 156 cases from New Delhi.

BACKGROUND: Photodermatitis is an abnormal response to ultraviolet radiation (UVR). The photoallergic contact dermatitis caused by plant allergens is a serious cause of morbidity in India. Airborne contact dermatitis is the classical presentation of plant-induced dermatosis, which may become difficult to differentiate from chronic actinic dermatitis in chronic cases. The rapid growth of parthenium weed in India and its ill effects on the population make it important to detect all cases of parthenium sensitivity, which in some cases might simulate photodermatitis. AIMS: This study aims to detect the occurrence of plant sensitivity and photosensitivity in idiopathic-acquired photodermatoses, airborne contact dermatitis and general population taken as controls. METHODS: One hundred and fifty six consecutive patients suffering from polymorphic light eruption (PMLE), chronic actinic dermatitis (CAD) and airborne contact dermatitis (ABCD) were enrolled in the study over a period of three years (June 2004 to May 2007). An equal number of age and sex matched healthy subjects were enrolled in the study as controls. All the patients were subjected to detailed history taking, clinical examination and histopathological examination for diagnosis. Patch and photopatch testing were perfomed in all the patients and healthy controls for detection of allergic and photoallergic reactions to parthenium, xanthium and chrysanthemum plant antigens and control antigens. RESULTS: Out of 156 patients enrolled in the study, 78 (50%) had CAD, 67 (42.9%) had PMLE and 11 (7.05%) had ABCD. The occurrence of parthenium/xanthium allergy and photoallergy, either to parthenium or both was most commonly found in ABCD (72.7%), followed by CAD (32%). In PMLE 4.5% cases showed photoallergy. Only 1.9% in the control group showed sensitivity to parthenium and xanthium. CONCLUSION: This study indicates that parthenium (and possibly xanthium) may act as important environmental factors in the initiation and perpetuation of not only ABCD but of CAD as well. Photoexacerbation to UVA at positive parthenium/xanthium sensitivity sites in ABCD and CAD indicates that ABCD with photosensitivity to compositae can lead to CAD.

A clinicoepidemiological study of polymorphic light eruption.

BACKGROUND AND AIMS: The prevalence of polymorphic light eruption (PLE) varies between 10-20% in different countries but no such data is available from India, where exposure to sunlight is high. METHODS: A clinico-epidemiological study of PLE was done in the skin outpatient department (OPD) of Institute of Medical Sciences Hospital from January to December. RESULTS: The ages of the patients varied from 5-70 years. Out of a total of 39,112 OPD cases, 220 cases of PLE (138 females and 82 males) were recorded, giving a prevalence of 0.56% in this study population. The skin type varied between IV and VI in 96% of the cases. Housewives were 81, students 67, office persons 39, farmers 22, businessmen 6 and unemployed 5. DISCUSSION: The manifestation of PLE was most common in housewives in areas exposed to the sun. Most of the PLE patients presented with mild symptoms and rash around the neck, forearms and arms which was aggravated on exposure to sunlight. PLE was more prevalent in the months of March and September and the disease was recurrent in 31.36% of the cases. CONCLUSIONS: The prevalence of PLE was 0.56%. It was mild in nature and only areas exposed to the sun were involved.