Ryckaert S, Roelandts R
Photodermatology Unit, University Hospital, Leuven, Belgium.
Arch Dermatol. 1998 Jan;134(1):71-4. doi: 10.1001/archderm.134.1.71.
Solar urticaria is a rare photosensitive disease, and its differential diagnosis with respect to polymorphous light eruption is sometimes difficult. We report our experience with 25 cases of solar urticaria and discuss the pitfalls in phototesting such patients.
The most important locations in this patient series are the V of the neck and the arms, which are similar to those of polymorphous light eruption. In all of the patients, however, the lesions appeared within 30 minutes of sun exposure or phototesting and disappeared within 24 hours. Notably, 12 (48%) of the patients had a history of atopy. Phototesting helps confirm the diagnosis, but, in some patients, this was difficult.
A negative phototest result from a single light source does not necessarily exclude a diagnosis of solar urticaria. In patients in whom phototesting elicits negative reactions, other light sources should be used, and, if the phototest result is still negative, a provocative test with natural sunlight should be done. Histamine1-receptor antihistamines are a useful first-line therapy, although more severely affected persons may require prophylactic courses of phototherapy or photochemotherapy. The main problem is maintenance treatment.
日光性荨麻疹是一种罕见的光敏性疾病，有时难以与多形性日光疹进行鉴别诊断。我们报告了25例日光性荨麻疹患者的治疗经验，并讨论了对此类患者进行光试验时的注意事项。
在这个患者系列中，最主要的发病部位是颈部V区和手臂，这与多形性日光疹相似。然而，所有患者的皮损在日晒或光试验后30分钟内出现，并在24小时内消退。值得注意的是，12例（48%）患者有特应性病史。光试验有助于确诊，但对一些患者来说，这有一定难度。
单一光源的光试验结果为阴性并不一定排除日光性荨麻疹的诊断。对于光试验出现阴性反应的患者，应使用其他光源进行试验，如果光试验结果仍为阴性，则应进行自然光激发试验。组胺1受体抗组胺药是一种有效的一线治疗方法，尽管病情较重的患者可能需要进行预防性光疗或光化学疗法。主要问题是维持治疗。
