摘要
Background: The severity of polymorphic light eruption (PLE)-is highly vari able. The results of studies of the prevalence, pathogenesis, provocation and tr eatment of PLE may be highly dependent on the severity of disease in the patient s studied. Objectives: To produce a simple, valid and reproducible method to ass ess the severity of PLE, Patients and methods: Eighty patientswere asked about t he PLE they had experienced during the preceding 12 months, using a standardized interview comprising 16 questions. The answer to each question received a score . A PLE Severity Index (PLESI) was formulated, consisting of 10 questions, with a possible total score of 2- 100. The internal consistency of the PLESI (the ex tent to which the responses to different questions correlated with each other) w as assessed by reliability analysis, using Cronbach’s method. Twenty patients were re-interviewed 7- 27 days later to assess the repeatability of the PLESI . The ease of provocation of PLE by exposure at 24- h intervals to solar-simu lated radiation was assessed on a five-point scale in nine of the 80 subjects (the EOPSSR score). Results The value of Cronbach’s α for the PLESI was 0.77 . The distribution of the PLESI was consistent with a normal distribution, with a mean value of 52.7 and standard deviation of 19.4. It had a coefficient of rep eatability of 20.1. The PLESI was positively correlated with EOPSSR (rs = 0.69, P=0.039) and the number of years since onset of PLE (rs=0.25, P=0.03). There was no association between the PLESI and the duration of persistence of the eruptio n after ceasing sun exposure (rs=0.12, P= 0.30), the development of tolerance as summer progressed (rs=- 0.14, P=0.39), gender (P=0.50) or skin type (P=0.87). Conclusions: This study has (i) validated the concept that a single score can re flect disease severity in PLE by showing that the principal characteristics of t he condition, including, for example, the extent of anatomical distribution and the ease of provocation of the eruption, correlate with each other; (ii) formula ted the PLESI, which is a simple, valid and reproducible way of assessing diseas e severity; we suggest it could be used worldwide to determine the severity of P LE among patients enrolled in future PLE research; (iii) shown that the ease wit h which the eruption is provoked by solar-simulated radiation correlates with the severity of the condition; and (iv) shown that the duration of persistence o f the eruption after sun exposure does not correlate with the severity of the co ndition.
Background: The severity of polymorphic light eruption (PLE)-is highly vari able. The results of studies of the prevalence, pathogenesis, provocation and tr eatment of PLE may be highly dependent on the severity of disease in the patient s studied. Objectives: To produce a simple, valid and reproducible method to ass ess the severity of PLE, Patients and methods: Eighty patientswere asked about t he PLE they had experienced during the preceding 12 months, using a standardized interview comprising 16 questions. The answer to each question received a score . A PLE Severity Index (PLESI) was formulated, consisting of 10 questions, with a possible total score of 2- 100. The internal consistency of the PLESI (the ex tent to which the responses to different questions correlated with each other) w as assessed by reliability analysis, using Cronbach's method. Twenty patients were re-interviewed 7- 27 days later to assess the repeatability of the PLESI . The ease of provocation of PLE by exposure at 24- h intervals to solar-simu lated radiation was assessed on a five-point scale in nine of the 80 subjects (the EOPSSR score). Results The value of Cronbach's α for the PLESI was 0.77 . The distribution of the PLESI was consistent with a normal distribution, with a mean value of 52.7 and standard deviation of 19.4. It had a coefficient of rep eatability of 20.1. The PLESI was positively correlated with EOPSSR (rs = 0.69, P=0.039) and the number of years since onset of PLE (rs=0.25, P=0.03). There was no association between the PLESI and the duration of persistence of the eruptio n after ceasing sun exposure (rs=0.12, P= 0.30), the development of tolerance as summer progressed (rs=- 0.14, P=0.39), gender (P=0.50) or skin type (P=0.87). Conclusions: This study has (i) validated the concept that a single score can re flect disease severity in PLE by showing that the principal characteristics of t he condition, including, for example, the extent of anatomical distribution and the ease of provocation of the eruption, correlate with each other; (ii) formula ted the PLESI, which is a simple, valid and reproducible way of assessing diseas e severity; we suggest it could be used worldwide to determine the severity of P LE among patients enrolled in future PLE research; (iii) shown that the ease wit h which the eruption is provoked by solar-simulated radiation correlates with the severity of the condition; and (iv) shown that the duration of persistence o f the eruption after sun exposure does not correlate with the severity of the co ndition.
