Chronic actinic dermatitis: A clinical study of 15 cases in northern Taiwan

Background Chronic actinic dermatitis (CAD) is an idiopathic photosensitive dermatosis induced by ultraviolet B (UVB), sometimes ultraviolet A (UVA), and occasionally visible light. Diagnosis is suggested by the clinical findings, typically a chronic eczematous rash on the sun exposed areas, and confirmed by phototesting, which demonstrates the abnormal photosensitivity. The aim of this study was to determine the characteristics of CAD in Taiwanese patients. Methods We retrospectively reviewed the clinical and photobiological features of all patients diagnosed as having CAD at our institute from 2002 to 2012. Results A total of 15 patients with CAD were identified. The mean age at diagnosis was 58.6 years (range, 28–82 years). All the patients were males. The face, neck, forearms, and dorsal hands were most commonly involved. Eight patients (53.3%) had decreased minimal erythema dose (MED) to both UVB and UVA; six patients (40.0%) had decreased MED to only UVB; one patient (6.7%) had decreased MED to only UVA. All were managed with photoprotection and topical corticosteroids. Four patients received azathioprine (50 mg twice a day to every other day) and one received prednisolone (10 mg per day to every other day). Conclusion In Taiwan, CAD affects elderly men more commonly. The most common phototest results were decreased MED to both UVB and UVA, followed by to UVB alone. All patients were managed with photoprotection and topical corticosteroids, and some also required systemic agents, in particular azathioprine.