Department of Dermatology, Rabin Medical Center, Beilinson Hospital, Petah Tiqwa, Israel.
J Eur Acad Dermatol Venereol. 2010 Sep;24(9):1026-30. doi: 10.1111/j.1468-3083.2010.03571.x. Epub 2010 Feb 17.
Idiopathic guttate hypomelanosis (IGH) is a common pigmentary disorder, the aetiology and pathogenesis of which are largely unknown. The appearance of IGH-like lesions during phototherapy has been reported previously in only one patient.
To describe the clinical and histological features of phototherapy-induced IGH-like lesions, their relation to ultraviolet dosimetry and the course of this eruption in patients with mycosis fungoides (MF).
The files of all patients with MF who underwent phototherapy in our centre from 1992 to 2008 were searched to identify those in whom IGH-like lesions appeared during treatment. Results Among 87 patients with early-stage MF who underwent phototherapy, seven acquired IGH-like lesions during monotherapy with narrow-band ultraviolet B (NB-UVB; four patients) or psoralen and ultraviolet A (PUVA; three patients). All but one had a light complexion. The lesions appeared in areas exposed to ultraviolet light, and not exclusively on the skin previously involved by the disease. The mean number of exposures until appearance of the lesions was 92 for NB-UVB and 137 for PUVA. Biopsy study showed a decreased number of melanocytes. Phototherapy was discontinued in four patients, of whom three showed a partial or complete disappearance of the IGH-lesions. The other three patients are still receiving phototherapy, with no change in their IGH-like lesions.
Phototherapy may induce an eruption bearing similar clinical and histopathological features to IGH. The eruption is rare, appears to emerge only after prolonged therapy and seems to be reversible upon discontinuation of phototherapy. IGH-like eruption should be added to the list of side-effects of phototherapy.
特发性点滴状色素减退症（IGH）是一种常见的色素障碍性疾病，其病因和发病机制尚不清楚。既往仅在 1 例患者中报道过光疗期间出现 IGH 样病变。
描述光疗诱导的 IGH 样病变的临床和组织学特征，及其与紫外线剂量测定的关系，以及蕈样肉芽肿（MF）患者中这种皮疹的病程。
检索了 1992 年至 2008 年在我中心接受光疗的所有 MF 患者的档案，以确定在治疗过程中出现 IGH 样病变的患者。
在 87 例接受早期 MF 光疗的患者中，7 例窄谱中波紫外线（NB-UVB；4 例）或补骨脂素加紫外线 A（PUVA；3 例）单一疗法治疗期间出现 IGH 样病变。除 1 例外，所有患者均为浅色皮肤。病变出现在暴露于紫外线的区域，而不仅仅是疾病先前累及的皮肤。NB-UVB 出现病变的平均照射次数为 92 次，PUVA 为 137 次。活检研究显示黑素细胞数量减少。4 例患者停止光疗，其中 3 例 IGH 病变部分或完全消失。另外 3 例患者仍在接受光疗，其 IGH 样病变无变化。
光疗可能会引发一种具有与 IGH 相似的临床和组织病理学特征的皮疹。这种皮疹很少见，似乎只在长期治疗后出现，并且似乎在停止光疗后可以逆转。IGH 样皮疹应添加到光疗的副作用列表中。
