PD15 The long road to diagnosis: a single-centre study of delays and disease burden in photodermatoses

Abstract Photodermatoses profoundly impact quality of life due to the visibility of photodistributed rashes, the burden of symptoms associated with them and the necessity of adherence to strict photoprotective methods, which can be very restrictive. Furthermore, it is thought that early recognition may be delayed for several reasons: misattribution to common skin conditions, the intermittent and seasonal nature of symptoms, a lack of awareness among nonspecialists, an overlap with other dermatological disorders, limited access to photodiagnostic centres, diagnostic challenges in darker skin tones, and insufficient patient awareness. This study aims to investigate whether these factors are contributing to diagnostic delays. This retrospective study reviewed electronic medical records of 70 adults with objective photosensitivity confirmed by monochromator and photoprovocation testing between 2021 and 2024. The cohort was predominantly female (79%) and White (84%), with a median age of photosensitivity onset of 25 years and a median age at diagnosis of 52 years. A history of atopic dermatitis was present in 47% of patients. The most prevalent diagnoses were photoaggravated dermatoses (44%), polymorphic light eruption (19%) and nonspecific photosensitivity (24%). The median diagnostic delay was 19 years (interquartile range 12–27), with 49% of patients experiencing delays > 20 years and 23% experiencing delays > 30 years. A progressive disease course was observed in 64% of patients, with only 11% reporting periods of remission. At the time of presentation, 37% of patients experienced near-continuous symptoms during the summer months, and 29% exhibited severe disease, as assessed by minimal erythemal thresholds and photoprovocation responses. The median annual Dermatology Life Quality Index (DLQI) score was 17 (interquartile range 12–21), indicating significant impairment in quality of life. This study reveals an alarming diagnostic delay in photodermatoses, often spanning decades, leading to significant disease burden. Early recognition remains a critical unmet need, necessitating improved awareness and targeted diagnostic strategies to improve patients’ health. Further research is required to address barriers to timely diagnosis and optimize patient outcomes.