误诊为银屑病及玫瑰糠疹的难辨认体癣一例

A Case of Tinea Incognito Misdiagnosed as Psoriasis and Pityriasis Rosea

摘要: 难辨认体癣常因外用糖皮质激素的干扰作用导致典型临床特征丧失，易与炎症性皮肤病混淆，误诊率较高。本文报道1例19岁女性患者，因躯干及股部红斑、脱屑伴瘙痒6个月就诊，皮损长轴与皮纹平行，既往曾诊断为玫瑰糠疹及银屑病，接受多种抗炎、抗过敏治疗，但疗效欠佳，病情迁延不愈。经真菌荧光染色镜检确诊为难辨认型体癣。给予口服伊曲康唑联合外用萘替芬酮康唑乳膏治疗2个月后，皮损明显改善直至消退，仅遗留少量色素沉着，随访6个月无复发。本病例提示，对于形态不典型、治疗无效的慢性红斑鳞屑性皮损，临床需警惕难辨认体癣的可能，应将真菌学检查作为常规诊断手段，避免因盲目使用糖皮质激素掩盖病情，导致误诊误治。

Abstract: Tinea incognito often loses its typical clinical features due to the interfering effects of topical corticosteroids, making it easily confused with inflammatory skin diseases and resulting in a high misdiagnosis rate. This report describes a 19-year-old female patient who presented with erythema, scaling, and pruritus on the trunk and thighs for 6 months. The lesions aligned parallel to skin creases. She had previously been diagnosed with pityriasis rosea and psoriasis, receiving various anti-inflammatory and anti-allergic treatments with poor efficacy and persistent disease. Fungal fluorescent staining microscopy confirmed the diagnosis of tinea incognito. After 2 months of treatment with oral itraconazole combined with topical naftifine ketoconazole cream, the lesions improved significantly and eventually resolved, leaving only minimal hyperpigmentation. No recurrence was observed during the six-month follow-up. This case highlights the need for clinical vigilance regarding the possibility of tinea incognito in chronic erythematous-scaly lesions with atypical morphology and treatment resistance. Fungal examination should be routinely performed to avoid misdiagnosis and inappropriate treatment resulting from masking symptoms with indiscriminate corticosteroid use.