The Intensive Study On The Clinical Assessment Of Photosensitivity And Related Spectrum In Lupus Erythematosus And Its Preliminary Investigation On The Photoprotection

Ultraviolet (UV) is one of the most important environmental factor in exciting lupus erythematosus(LE), part of LE patients being photosensitive. In this paper, based on the investigation of association of sunlight exposure and photoprotection measures with clinical systemic lupus erythematosus (SLE) patient's condition, the clinical assessment of the photosensitivity of LE, the spectrum of photosensitivity and the photoprotection of LE are investigated. This study consists of three parts.Part I Clinical investigation of photosensitive SLEObjective To study the relationship between sunlight exposure, UV protection measures and SLE patient's condition, to inquire the status of photosensitivity of LE determined by the clinical dermatologists, to evaluate the feasibility of determining the photosensitivity of LE with rountine phototesting and to investigate the correlation of the phototesting results with the clinical and immunological parameters. Methods A structured questionnaire was administered to SLE patients, to assess their attitudes and behavior regarding sunlight exposure and photoprotection measures. The clinical manifestations, laboratory findings and treatment were evaluated. Dermatologists filled out the questionnaire about the assessment of the photosensitivity of the LE. LE patients underwent the ultraviolet-A(UVA) minimal erythema dose(MED) and the ultraviolet-B(UVB) MED measurement. The correlation of the phototesting results with the clinical and immunological parameters was also evaluated. Results The patients who exposed to direct sunlight on an average of <1h per day had significantly decreased photosensitivity, arthritis, alopecia, number of exacerbations, anti-dsDNA antibody, complement C3 ,C4 and CH50 as compared with those in the group exposed to sunlight (?) 1h (P<0.05). The incidence of renal involvement was not different in two groups. However, the degree of severity of renal involvement was lower and also the interval of renal improvement was shorter in the former than in the latter group (P<0.01 and P<0.05). The patients who exposed < 1h per day required less hydroxychloroquine, medium to high dose of corticosteroid and CTX pulse treatment to control their disease than those required in patients who exposed more. One of the 11 American College of Rheumatology Criteria for the diagnosis of SLE — photosensitivity, was the most constant method used by the dermatologists to determine the photosensitivity of LE.