Background: Erythropoietic protoporphyria (EPP) is a rare inherited photodermatosis that causes lifelong painful photosensitivity. Neither its full clinical spectrum nor its impact on quality of life (QoL) has been investigated in a large cohort of patients. Objectives: To document the clinical features of EPP and its impact on QoL in a high proportion of all patients with EPP resident in the U.K.Methods: Patients with EPP were identified fromU.K. clinical databases and assessed by the same clinical investigator over a 7-month period using a standardized proforma and validated adult (Dermatology Life Quality Index, DLQI) and children’s (Children’sDermatology Life Quality Index, CDLQI) QoL questionnaires. Results: Three hundred and eighty-nine living patients with EPP were identified, of whom 223 [114 females, 109 males; median age 34 years (range: 5-87), from 193 families] were investigated. Total erythrocyte porphyrin (TEP) was higher in males (median: 25.3 μmol L-1)-than females (median: 19.3 μmol L-1). The median ages at onset and diagnosis were 1 and 12 years, respectively. Median times for onset of symptoms after sun exposure, onset of signs (oedema, erythema) and resolution of symptoms were 20 min, 6 h and 3 days, respectively. Most patients reported absence of protection by glass (92%), priming (85%), exacerbation by wind (68%), no family history of photosensitivity (56%), no symptoms during winter (56%) and had chronic skin lesions (79%). Symptoms changed little with age but improved during pregnancy in 47%of gravid women. Most patients used protective clothing and a sunscreen; 28%were taking β-carotene and a further 56%had taken it; 29%were not under regular medical care. Two patients (1%) had liver failure and 8%reported gallstone disease. QoL was markedly impaired, with scores similar to those in severe dermatological disease (mean DLQI score 14.0, n = 176; mean CDLQI score 12.8, n = 44), indicating a large effect on patients’lives. DLQI scores correlated weakly with TEP (rs = 0.228; P = 0.002) and time to onset of symptoms (rs = -0.233; P = 0.002) but not with age at onset. Conclusions: EPP is a persistent, severely painful, socially disabling disease with amarked impact on QoL. Its diagnosis is often overlooked. None of TEP, age at onset nor time to onset of symptoms is a useful predictor of impaired QoL in individual patients.
展开▼
