Research Center, Nihon Nohyaku Co., Ltd., 345 Oyamada-cho, Kawachi-Nagano, Osaka 586-0094, Japan.
Department of Dermatology, Tokyo Medical University, 6-7-1 Nishishinjuku, Shinjuku-ku, Tokyo, 160-0023, Japan.
Med Mycol. 2020 Aug 1;58(6):820-826. doi: 10.1093/mmy/myz128.
Seborrheic dermatitis (SD) is a multifactorial disease in which Malassezia restricta has been proposed as the predominant pathogenic factor. However, experimental evidence supporting this hypothesis is limited. A guinea pig SD model using a clinical isolate of M. restricta was used to elucidate the pathogenicity of M. restricta. Also, the efficacy of 1% luliconazole (LLCZ) cream, a topical imidazole derivative, against M. restricta was compared with that of a 2% ketoconazole (KCZ) cream in the same guinea pig model. Dorsal skin hairs of guinea pig were clipped and treated with M. restricta by single or repeated inoculations without occlusion. Skin manifestations were examined macroscopically and histologically. A quantitative polymerase chain reaction (PCR) assay was also performed for mycological evaluation. An inflammatory response mimicking SD occurred after repeated as well as single inoculation but not in abraded skin. The inflammation score attained its maximum on day 11 and persisted until day 52. The yeast form of the fungal elements was distributed on the surface of stratum corneum and around the follicular orifices, and an epidermal and dermal histological reaction was observed. Application of 1% LLCZ or 2% KCZ cream significantly improved the skin manifestations and decreased the quantity of M. restricta rDNA in the skin lesions. The efficacy of topical antifungal drugs suggested that M. restricta is a pathogenic factor contributing to SD.
脂溢性皮炎（SD）是一种多因素疾病，其中限制马拉色菌已被提议为主要致病因素。然而，支持这一假设的实验证据有限。使用限制马拉色菌的临床分离株建立豚鼠 SD 模型，以阐明限制马拉色菌的致病性。还比较了局部咪唑衍生物 1%卢立康唑（LLCZ）乳膏和 2%酮康唑（KCZ）乳膏在相同豚鼠模型中对限制马拉色菌的疗效。豚鼠背部皮肤毛发被剪短，并用限制马拉色菌进行单次或重复接种而不进行封闭处理。宏观和组织学检查皮肤表现。还进行了定量聚合酶链反应（PCR）检测以进行真菌学评估。重复和单次接种后会发生类似于 SD 的炎症反应，但在擦伤的皮肤上不会发生。炎症评分在第 11 天达到最大值，并持续到第 52 天。真菌元素的酵母形式分布在角质层表面和毛囊口周围，并观察到表皮和真皮组织学反应。应用 1% LLCZ 或 2% KCZ 乳膏可显著改善皮肤表现并减少皮肤病变中限制马拉色菌 rDNA 的数量。局部抗真菌药物的疗效表明限制马拉色菌是导致 SD 的致病因素。
